JP2010230307A - Refrigerating method and refrigerating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in a conventional refrigerating device that it is difficult to measure an exact temperature with respect to a food covered by plastic wrap and the like since a temperature of the food is measured by using an infrared ray sensor, thus it is difficult to keep a supercooling state which requires delicate temperature management. <P>SOLUTION: This refrigerating device includes a refrigerating compartment 200 for refrigerating the food 81 by introducing cold air, a temperature measuring means 50 for measuring a temperature of the food 81 stored in the refrigerating compartment 200, and a control means 46 for adjusting the cold air introduced to the refrigerating compartment 200 so that the food 81 stored in the refrigerating compartment 200 is kept in the supercooling state free from freezing even at a temperature lower than a freezing point on the basis of the measurement result of the temperature measuring means 50, and the temperature measuring means 50 is arranged so as to be lowerable toward the food in the refrigerating compartment 200. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a frozen storage method and a frozen storage device (such as a refrigerator, a freezer, and a frozen container) that can maintain a supercooled state that does not freeze even at temperatures below the freezing point.

  As a conventional frozen storage method and frozen storage device, there is an apparatus that measures the temperature of food with an infrared sensor arranged on the upper surface of the freezer and controls the temperature so as to maintain the supercooled state based on the measurement result. (For example, refer to Patent Document 1).

Japanese Patent No. 3903066 (6th page, FIG. 6)

  However, food is usually covered with a wrap or aluminum foil, and it has been difficult to measure the accurate temperature of the food with an infrared sensor. For this reason, it has the subject that it is difficult to maintain the supercooled state in which delicate temperature management is required.

  An object of the present invention is to solve such problems and provide a frozen storage method and a frozen storage apparatus that can measure the temperature of food with high accuracy.

  The frozen storage method of the present invention includes a freezing room that introduces cold air to store food in a frozen state, a temperature measuring means that measures the temperature of the food stored in the freezing room, and a frozen result based on the measurement result of the temperature measuring means. Control means for adjusting the cold air introduced into the freezer room so that the food stored in the room is maintained in a supercooled state that does not freeze even at a temperature below the freezing point. It is provided so that it can descend.

  In the frozen storage method according to the present invention, since the temperature measuring means can be lowered toward the food in the freezer compartment, the temperature of the food can be measured by bringing the temperature measuring means into direct contact. For this reason, even when food is covered with wrap or aluminum foil, the temperature of the food can be measured with high accuracy, and a supercooled state that requires delicate temperature control must be maintained. Becomes easy. As a result, the effect that the quality of food preservation can be improved is obtained.

First, supercooling will be described. FIG. 1A is a graph showing a change in temperature when water is frozen without “overcooling”. FIG. 1B is a graph showing a temperature change when water is frozen with “with supercooling”. The vertical axis of the graph is the temperature, and the temperature increases as it goes upward. The horizontal axis is time, and the passage of time is shown in the direction of the arrow.
A supercooled state refers to a state where the material is not frozen by 100% despite being below the freezing point of the substance. Here, the freezing point refers to the temperature at which the substance begins to freeze. That is, the supercooled state is a state at which the temperature should start freezing but is not frozen at all. For example, the freezing point of water is 0 ° C. This freezing point varies depending on the substance, and tends to be lower than 0 ° C. in foods having a high salt concentration and high sugar content.

  The supercooled state and the freezing after the supercooled state will be described in more detail by taking water as an example. When the water is cooled, the supercooled state is a state of 100 percent water even when the freezing point falls below 0 ° C. That means. Water that has entered a supercooled state can eventually freeze and become ice, but at this time, some kind of stimulation is necessary. This stimulus may be temperature or physical. In this way, freezing can be started by stimulation, but the time from the supercooling state to the start of freezing is in units of several seconds and is instantaneous. However, the proportion of water that freezes instantaneously at the start of freezing is several percent of the total, and it takes further cooling time before it becomes 100 percent ice.

Here, the difference between normal freezing and supercooled freezing will be described in comparison. First, the main difference between normal freezing and supercooling freezing is whether or not a supercooled state is entered. In the case of normal freezing, when the freezing point is passed, freezing starts without entering the supercooling state.
Another major difference between normal freezing and supercooling freezing is the state at the start of freezing.

  Here, the phenomenon that occurs at the start of freezing will be explained using water in a plastic bottle as an example. In normal freezing, when freezing starts, the water near the surface of the plastic bottle begins to freeze. It becomes a state where thin ice is applied to the part, then the ice spreads toward the inside, and finally the whole freezes. Ice growth occurs mainly around ice nuclei in which water molecules form clusters of a certain size or more, and ice nucleation occurs at the start of freezing. Therefore, in the case of normal freezing, it can be said that ice nuclei are formed on the surface, and the ice grows from there to the portion that is in the water state.

On the other hand, in the case of supercooled freezing, ice nuclei are uniformly formed in the entire PET bottle when freezing starts. And because the ice grows in every part of the PET bottle, both inside and on the surface, the ice never grows in a certain direction.
The difference between normal freezing and freezing after completion of freezing is due to the difference in the cooling process. In normal freezing, large acicular ice crystals from the surface to the inside are formed, whereas in freezing freezing. Produces uniformly small granular ice crystals on the surface and inside.

Further, in the case of quick freezing, the state at the start of freezing and after the completion of freezing is the same as in the case of normal freezing in that it is quickly frozen by applying cold air to the surface.
First, the temperature of the surface suddenly drops, so it begins to freeze from the surface. However, the difference from normal freezing is that the cooling rate to the inside increases, so that ice nuclei are more likely to form inside than normal freezing, and no larger ice crystals are formed than during normal freezing.

  When considering food freezing, the size and shape of ice crystals after freezing has a significant effect on the quality of food when thawed. Since food is mostly composed of cells, proteins, carbohydrates, etc., once its structure is destroyed by ice crystals, it often cannot be completely restored. Therefore, it can be said that freezing with good quality has been achieved if the size and shape of the ice crystals formed upon freezing does not destroy the original structure of the food.

  Next, the merit and novelty of freezing food by supercooled freezing will be described. The greatest merit of freezing food with supercooled freezing is that it can be frozen with good quality. As described above, in freezing after a supercooled state, the inside of the food is sufficiently cooled in the process of being supercooled, so that ice nuclei are uniformly formed throughout the food, and small granular ice is formed. Grows into crystals. In addition, the larger the difference between the minimum temperature reached in the supercooled state and the freezing point (the difference between the points A and B in FIG. 1B), the larger the number of ice nuclei formed at the start of freezing. , Become finer ice crystals. Therefore, if the supercooling sufficiently occurs (the lower the temperature reached in the supercooled state is), it is possible to maintain a state closer to that before freezing after freezing → thawing.

When considering the cooling of food and the size and shape of ice crystals, it has been conventionally performed to consider the passage time in the temperature zone of -1 ° C to -5 ° C, which is the maximum ice crystal formation zone. The idea is that ice crystals become smaller if they pass through this maximum ice crystal formation zone in a short time.
In the case of supercooled refrigeration, it takes a long time to stay in the supercooled state in the temperature range (around -1 ° C to -10 ° C) including this maximum ice crystal formation zone. However, the supercooled state is a state that is not frozen. Therefore, in the supercooled state, the ice crystals after freezing do not become large even if this temperature zone passage time is long, and it is possible to make fine ice crystals. It is a completely new refrigeration method in that small ice crystals are formed by freezing in a temperature range around this including the maximum ice crystal temperature range, and freezing is performed with good quality.

In addition, freezing starts when the supercooling state is released, and it completely freezes through a phase change state in which the temperature does not change, but if it has passed through the supercooling state, it will reach the maximum ice crystal formation zone in the subsequent freezing process. Even if it stays for a long time, it has been confirmed that ice crystals do not enlarge. Therefore, it can be said that this is also a novel refrigeration method.
If it has been overcooled, even if the subsequent freezing process takes a long time, there is almost no effect on the ice crystal state. It can be further reduced, and it is possible to avoid food quality deterioration factors other than ice crystals.

In addition, up to now, only the merit in the case where the food that has entered the supercooled state is released after being supercooled and frozen is described, but it is not always necessary to freeze the food that has entered the supercooled state.
The merit of maintaining the supercooled state is that the ice crystals are not formed at all, even though it is stored at a temperature below the freezing temperature, that is, at a temperature that would normally freeze. For this reason, the food structure is not affected by ice crystals at all while being stored at a low temperature. Although it is generally known that storage at a lower temperature is effective for preserving freshness in that various chemical changes in food can be suppressed, both this low-temperature storage and unfrozen It can be said that it is a storage method that can achieve the merits of.

  There is no need to thaw the food. However, being in an unfrozen state also has a disadvantage. The fact that moisture in food is not frozen means that it can be used for bacterial growth and various chemical changes. Therefore, care must be taken in this regard rather than frozen ones.

Next, conditions for realizing supercooling will be described. The most important point when setting the supercooling condition is the difference between the freezing point and the minimum point of reaching the core temperature of the food to be cooled (the temperature reached in the supercooled state).
If the cooling rate is too fast, the whole food is cooled in a non-uniform state, so that a frozen part (a large difference between the surface temperature of the food and the core temperature) and an unfrozen part are formed. Since ice crystals grow around ice nuclei, if a portion of the food freezes, it grows while taking in moisture from the unfrozen portion. As a result, large acicular ice crystals are formed. Needle-shaped ice crystals or large ice crystals generated between cells cause water outflow and cell destruction in the cells and cause drip outflow when the food is thawed. As a result, the original taste of the food is reduced or the texture is deteriorated.

On the other hand, if the cooling rate is too slow, there is no problem in maintaining the supercooled state, but the unfrozen state becomes longer, which causes a problem that food quality deteriorates due to bacterial propagation, oxidation promotion, and the like.
In other words, it is cooled so that the difference between the surface temperature and the core temperature becomes small until the freezing point, and when the temperature reaches the freezing point or lower (supercooled state), the cooling rate is increased and the core temperature reaches the lowest point. The supercooling is released so that the unfrozen state does not become longer. In this way, the temperature control and the temperature zone until the food is released from the supercooling to the freezing point, to the supercooling state below the freezing point, and completely frozen are performed continuously or stepwise. In order to solve such a problem, there is a method of adding an antibacterial function to the supercooling space. Examples of the antibacterial function include a method using ultraviolet rays and ozone. However, there is also a problem that it is costly to add an antibacterial function.

  Considering the above, it is necessary to limit the cooling rate to some extent. For example, in foods such as pudding and yogurt, the core temperature is set to a cooling rate in the range of 300 ° C./h to 0.35 ° C./h, preferably around 3.5 ° C./h to create a supercooled state. The cooling rate is such that the core temperature is within a temperature range from the freezing point to 20 ° C. lower than the freezing point, preferably from the freezing point to −10 ° C.

Further, the supercooled state needs to be maintained for a certain time, for example, 5 seconds or more. This is to make the supercooling temperature deeper. In other words, lowering the temperature at which the food reaches in the supercooled state.
The reason why the subcooling temperature should be deep may be as follows. As the supercooling temperature becomes deeper, the amount of sensible heat energy stored in the supercooling increases. As a result, the energy of the instantaneous latent heat change used when the supercooling is released increases. Many ice nuclei are generated in the food at the same time when the cooling is released, and ice crystals grow using the ice nuclei as nuclei, so that a large number of small ice grains can be formed uniformly in the food, affecting the cells. It can be said that it becomes smaller.

Further, the difference from the surface temperature when the core temperature reaches the temperature at which supercooling can be released is preferably in the range of 0 ° C. to 10 ° C., preferably within 5 ° C. The difference between the surface temperature and the core temperature is about 1 ° C. if the beef leg meat has a thickness of 15 mm and 150 g.
The range about the above cooling conditions can be said similarly about foodstuffs, such as meat, fish, vegetables, and fruits.

Examples of the second supercooling condition include fluctuations in the air temperature in the supercooling space (temperature differences due to time).
The width of the air temperature fluctuation is preferably within 5 ° C. However, if the temperature is within 15 ° C., the quality may deteriorate somewhat, but it is possible to create a supercooled state. The reason why food quality deteriorates when the air temperature fluctuation range is large is that ice crystals grow slightly larger by repeated freezing and thawing. As another means for reducing the air temperature fluctuation range, the fluctuation range predetermined in the microcomputer or the like may be reduced in order to control the device based on the detection value of the thermistor. It is preferably within 4K (4 ° C), more preferably within 1K (1 ° C).

As the third supercooling condition, air temperature unevenness (temperature difference depending on location) in the supercooling space may be mentioned.
The air temperature unevenness may be within 15 ° C., but is preferably within 5 ° C. The problem of air temperature unevenness being too large is that partial freezing occurs when trying to cool large foods.

  Here, the temperature setting reference | standard of supercooling freezing is described. Examples of the temperature zone that satisfies the cooling rate as described above and has a high probability of occurrence of supercooling include −3 ° C. to −10 ° C. In this temperature range, the freezing point of most foods that are thought to be frozen is included, so that it is possible to freeze them stably after supercooling. In addition, the food storage period in such a temperature range is about two weeks. For example, even if the food purchased by bulk purchase on the weekend cannot be used due to a change in schedule or the like, it can be stored with confidence until the next week. Moreover, if it preserve | saves after freezing in this temperature range, since it can cut with a kitchen knife etc., without thawing | decompressing, the effort of cooking can be saved.

  FIG. 2 is a diagram showing the state of the meat tissue when the meat is frozen by normal quick freezing and supercooling freezing, and when the frozen meat is once thawed. Thus, it is known that if the ice crystals formed inside when meat or fish are frozen are large, the cells are destroyed and the amount of drip after thawing increases. Therefore, when comparing the amount of drip of supercooled frozen and normal frozen beef tuna and tuna, the tendency of supercooled frozen to be reduced to less than half that of normal frozen is seen.

  Potatoes, such as potatoes, have traditionally been considered unfit for freezing. When making curry etc., storing it frozen and eating it again after the next day is a common practice in ordinary households, but at that time, only potatoes are removed or crushed It has been said that freezing is a common sense for freezing curry. This is because when potatoes are frozen and thawed, they become scary and the texture becomes worse. However, it is known from experimental results that when the curry is frozen by supercooled freezing, the texture of the potato is almost the same as that before freezing after thawing, and it does not become a scary texture or a sticky texture. Starch, which is the main ingredient of potato, is composed of amylose and amylopectin, but it was conventional freezing that destroyed the three-dimensional structure by the growth of ice crystals. Once a structure has been destroyed, it will not return to its original state after being decompressed.

  On the other hand, since the ice crystals produced by supercooled freezing are very fine, the three-dimensional structure of starch is hardly deformed during freezing, and the original three-dimensional structure can be maintained even after thawing. Therefore, it is considered that the texture of potatoes thawed after supercooled freezing does not deteriorate. Such a principle may also apply to other foods that have been considered unsuitable for freezing, so using supercooled freezing allows foods that were previously considered unsuitable for freezing to be frozen. Is also suggested.

  Thus, it has been found that when foods are frozen through a cooled state, fine ice crystals are formed, so that the original food structure such as cells and proteins can be maintained without change. Therefore, there is a possibility that the quality will not be extremely deteriorated as in the conventional freezing even if the freeze-thaw is repeated, for example, the frozen-thawed food is frozen again.

  The above describes the merits of utilization in general households, but it can be said that supercooled refrigeration can be used effectively in food processing. The result is that the fineness of ice crystals produced by supercooled freezing is superior to that of -60 ° C, and it can be said that it can be replaced with a commercial freezer in terms of realizing high-quality freezing. In addition, there is an advantage in that energy saving is high because it is not necessary to create cryogenic cold air using a large amount of energy for business use.

Next, preferred embodiments of a frozen storage method and a frozen storage device according to the present invention will be described with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 3 is a cross-sectional view illustrating a structure of a refrigerator that is an example of a cryopreservation apparatus according to Embodiment 1. The refrigerator 1 has a refrigerator compartment 100 having an open / close door at the top, a freezer compartment 200 having a supercooling function arranged with a drawer door below the refrigerator compartment 100, The freezer compartment 300 without a supercooling function is provided with a drawer door at the bottom, and the vegetable compartment 400 is provided with a drawer door between the freezer compartment 200 and the freezer compartment 300. On the door surface of the refrigerator 100, an operation switch for adjusting the temperature and setting of each room and an operation panel 5 for displaying the temperature of each room at that time are provided.

  A compressor 10 and a cooler 3 constituting a refrigeration cycle are arranged on the back side of the refrigerator 1, and a fan 2 for blowing the cold air cooled by the cooler 3 to the refrigerator compartment 100 and the freezer compartment 200; An air passage 4 for introducing the cold air cooled by the cooler 3 into the refrigerator compartment 100 is provided.

  The freezer compartment 200 is provided with a storage case 201 that can be pulled out and has an open upper surface, and can store food in these cases. Similarly, a freezer case 301 is installed in the freezer compartment 300, and a vegetable case 401 is installed in the vegetable compartment 400.

  4 and 5 are cross-sectional views showing a side structure of the freezer compartment 200 according to the present embodiment. The freezer compartment 200 is provided with a freezer compartment air passage 41 that guides the cold air from the air passage 4 to the freezer compartment 200 via a damper (control means) 46. A freezer compartment rear upper outlet 42 on the upper left side of the refrigerator 1 as viewed from the front side of the refrigerator 1 and a freezer compartment ceiling outlet 43 on the front side of the ceiling are provided as cold outlets. Further, the freezer compartment 200 is provided with a freezer compartment back surface suction port 44 at the lower right of the back surface and a freezer compartment bottom surface suction port 45 at the bottom surface.

A rectangular temperature measuring member 50 that measures the temperature of the food 81 stored in the freezer compartment 200 is suspended from the ceiling of the freezer compartment 200 by a wire 51 at the top of the freezer compartment 200. One end of the wire 51 is attached to the corner of the temperature measuring member 50, and the other end is attached to the winder 53 via the roller 52.
As shown in FIG. 6, the temperature measuring member 50 includes a flexible sheet-shaped temperature sensor base 50a and a plurality of temperature sensors 50b arranged in a matrix on the temperature sensor base 50a. For this reason, the temperature distribution of each part of the food 81 can be accurately measured, and control for uniformly cooling the food 81 is facilitated.

Also, as shown in FIGS. 4 and 5, a bowl-shaped piece 201 a is provided at the lower rear end of the housing case 201, and a drive shaft that moves up and down of the actuator 200 a provided on the bottom surface of the rear end of the freezer compartment 200, It is configured to be engageable with the hook-shaped piece 201a.
Furthermore, a notification lamp 200b is provided on the door surface of the freezer compartment 200 to turn on and notify the storage case 201 so as not to be pulled out while the temperature measuring member 50 is lowered.
The winder 53, the actuator 200a, and the notification lamp 200b are controlled by a control device (not shown), and drive and control the actuator 200a and the notification lamp 200b in conjunction with the operation of the winder 53.

  Next, the supercooling control of the freezer compartment 200 will be described. Here, the supercooling release timing is determined based on the accumulated time from the start of supercooling, and the supercooling release is performed by changing the air temperature around the food to the low temperature side. FIG. 7 is a timing chart showing control of the refrigerator at this time. In order to supercool the food stored in the storage case 201, until the core temperature of the food in the storage case 201 exceeds the freezing point and reaches a supercooled state (stage 1), the compressor 10, the fan 2, the damper 46, etc. However, it operates so that the room (here freezer compartment 200) in which the storage case 201 is stored has an air temperature selected in the range of, for example, -2 ° C to -20 ° C. The compressor 10 and the fan 2 may be controlled by the temperature of another room, and the temperature may be controlled only by opening / closing the damper 46.

  In this stage 1, the set temperature of the freezer compartment 200 is assumed to be the same as that in the normal state (indicated as “Tset” in FIG. 7). When the supercooling can be released (refers to a state where the food temperature is supercooled to a temperature 3 ° C. or more lower than the freezing point) (after holding the supercooled state for at least 5 seconds) (stage 2), After the cooling is released, until the whole food is completely frozen (stage 3), the set temperature of the freezer compartment 200 may be set to the normal temperature setting (Tset), but the set temperature is lowered ("Tset-" in FIG. 7). down), and the temperature of the freezer compartment 200 may be shifted down. In that case, the certainty of cancellation of supercooling is increased, and the freezing quality is improved because the cooling rate after the cancellation is fast. In addition, the freezing quality is further improved by rapid cooling so that the temperature in the supercooling case is lowered to −20 ° C. or lower as in normal quick freezing and freezing at once.

  With regard to the storage temperature setting after the food is completely frozen (Stage 4), if the temperature is set to a high temperature side such as −15 ° C. or higher, the energy saving is enhanced, and even if stored frozen at −5 to −10 ° C., from the refrigerator. Easy to use because it is cut with a knife immediately after taking it out. Further, when the temperature is set to a low temperature such as −15 ° C. or lower, the storage stability is enhanced.

  Next, the operation of the present embodiment will be described. As shown in FIG. 4, in the state where the wire 51 is wound around the winder 53, the temperature measuring member 50 is pulled up near the ceiling of the freezer compartment 200. In this state, since the temperature measurement member 50 does not come into contact when the housing case 201 is pulled out, the actuator 200a retracts the drive shaft downward by a control device (not shown), and the hook-shaped piece 201a and the drive shaft Is disengaged. For this reason, the storage case 201 can be pulled out freely. In this state, the notification lamp 200b is also turned off by a control device (not shown).

Next, when the food 81 in the freezer compartment 200 is shifted to the supercooled state, it is necessary to lower the temperature measuring member 50 and measure the temperature of the food 81 with high accuracy. Therefore, as shown in FIG. 5, the wire 51 is fed out from the winder 53 and the temperature measuring member 50 is lowered. By this lowering, the temperature measuring member 50 enters the housing case 201 whose upper surface is opened, and the flexible sheet-shaped temperature measuring member 50 covers the food 81. For this reason, it is possible to measure the temperature of the food 81 by bringing the temperature measuring member 50 into almost direct contact, and even when the food is covered with a wrap or aluminum foil, the food 81 can be accurately measured. It becomes possible to measure temperature. For this reason, it becomes easy to maintain the supercooled state in which delicate temperature management is required, and the quality of food preservation can be improved.
Further, since the temperature sensor base 50a has flexibility, even when a plurality of foods 81 having different heights are stored, the foods 81 can be surely brought into direct contact with each other.

  Further, in this state, when the storage case 201 is pulled out, the storage case 201 and the temperature measurement member 50 come into contact with each other. Therefore, the actuator 200a pulls the drive shaft upward by a control device (not shown) to 201a and the drive shaft are engaged. For this reason, the storage case 201 cannot be pulled out, and the temperature measurement member 50 can be prevented from being destroyed because the storage case 201 is forcibly pulled out. Further, in this state, the notification lamp 200b is lit by a control device (not shown), so that the user can easily recognize that the storage case 201 cannot be pulled out. For this reason, it is possible to prevent an excessive load from being applied to the drive shaft of the actuator 200a and the hook-shaped piece 201a when the user forcibly pulls out the housing case 201.

  Furthermore, in the state where the temperature measurement member 50 is lowered, the freezer compartment back side upper blowout port 42 and the freezer compartment ceiling surface blowout port 43 that are cold air blowout ports are provided above the temperature measurement member 50, so The cold air from the mouths 42 and 43 is indirectly given to the food 81 through the temperature measuring member 50. For this reason, it is possible to prevent direct blowing of cold air to the food 81, and it is an important condition when creating a supercooled state. The temperature fluctuation is small, and the entire food 81 is evenly distributed at a slow cooling speed. Therefore, it is possible to ensure an environment that is easily overcooled. Furthermore, drying of food by direct spraying of cold air is reduced, and freezing and burns can be suppressed.

Moreover, as shown in FIG. 8, the temperature measurement member 50 may arrange | position the several ventilation hole 50c which guides cold air | gas to a foodstuff in a matrix form. In this case, the cold air from each of the outlets 42 and 43 is dispersed and given to the food 81 from each of the vent holes 50c. For this reason, since the blowing of cold air to the food 81 can be alleviated, there is little temperature fluctuation, which is an important condition when creating a supercooled state, and the entire food 81 is made uniform at a slow cooling speed. It becomes possible to cool, and the environment which is easy to supercool can be secured. Furthermore, drying of food by direct spraying of cold air is reduced, and freezing and burns can be suppressed.
The temperature sensor base 50a of the temperature measuring member 50 is preferably made of a material having low air permeability such as vinyl, rubber, or plastic. However, the material is not limited to these materials, and the material having high air permeability such as cloth. May be used. If the material has high air permeability, cold air is given to the food from the entire surface of the temperature measuring member 50 without opening the air vent 50c, and the entire food 81 can be uniformly cooled.
Moreover, you may comprise the temperature measurement member 50 with the bag body which enclosed the cool storage agent inside. The temperature measuring member 50 enclosing the cool storage agent absorbs the temperature change when the cold air is intermittently introduced and relaxes the temperature change of the freezer compartment 200. Therefore, it becomes easy to maintain the supercooled state, and the food. The quality of preservation can be improved. Furthermore, it is good also as control which lowers | hangs the temperature measurement member 50 at the time of the removal operation of the frost adhering to the cooler 3, and this reduces the temperature rise of the foodstuff in the freezer compartment 200 at the time of the removal operation of frost, and quality of food preservation | save Can be improved.

  As described above, the temperature measuring member 50 includes the temperature sensors 50b arranged in a matrix. When the temperature measuring member 50 is lowered, the temperature of the portion where the food 81 is present becomes higher than the portion where the food 81 is not present, so that the region occupied by the food 81 on the bottom surface of the housing case 201 is each temperature sensor 50b. It can be easily detected from the measurement result. Therefore, a control device (not shown) can estimate the amount of the food 81 by obtaining information on the area occupied by the food 81 from the measurement result of each temperature sensor 50b. A control device (not shown) controls the temperature of the freezer compartment 200 based on the amount of the food 81, thereby realizing more accurate temperature management.

  When the above supercooling control is completed and the supercooled state is released, the wire 51 is wound up by the winder 53 and the temperature measuring member 50 is raised. As the temperature measuring member 50 rises, the cold air from the outlets 42 and 43 is directly blown onto the food 81, and the freezing of the food 81 is promoted. As a result, the effect that the demerit (food quality deterioration by bacteria reproduction, oxidation promotion, etc.) by prolonged unfrozen state can be suppressed is exhibited.

  The temperature measuring member 50 is not limited to a flexible sheet shape, and may be a plate shape with less flexibility. In this case, even if the temperature measurement member 50 is lowered due to the unevenness on the upper surface of the food 81, a portion that is not completely in contact may occur. However, even in this case, the temperature measurement is almost directly contacted, and it is possible to measure the temperature of the food 81 with higher accuracy than in the case where the measurement is performed with a conventional infrared sensor. It becomes. Alternatively, the temperature measuring member 50 may be lowered to a position close to the food 81 and the temperature of the food 81 may be measured without direct contact. Also in this case, it is possible to measure the temperature of the food 81 with higher accuracy than in the case where the measurement is performed by using a conventional infrared sensor.

Embodiment 2. FIG.
Next, a refrigerator that is an example of a cryopreservation device according to Embodiment 2 will be described. FIG. 9 is a cross-sectional view showing a side structure of freezer compartment 200 according to the present embodiment. The second embodiment is different from the first embodiment in that an RFID tag (temperature measurement means) 60 that wirelessly transmits a measurement result of the temperature of the food 81 is provided instead of the temperature measurement member 50. Other configurations are the same as or equivalent to those of the first embodiment. In addition, the same code | symbol is attached | subjected about the component which is the same as that of Embodiment 1, or equivalent, and the description is abbreviate | omitted.

  As shown in FIG. 9, a plurality of RFID tags 60 that are non-contact type IC chips are incorporated in the bottom surface of the housing case 201. In addition, a transmission / reception unit 71 that communicates with the RFID tag 60 wirelessly is disposed on the upper surface of the freezer 200. In addition, the transmission / reception unit 71 is not limited to the upper surface part of the freezer 200, You may arrange | position to a side part or a bottom face part. In particular, when the transmission / reception unit 71 is disposed on the bottom surface of the freezer 200, the distance from the RFID tag 60 incorporated in the bottom surface of the housing case 201 is narrowed, so wireless communication can be reliably performed even with weak radio waves. it can.

  As illustrated in FIG. 10, the RFID tag 60 transmits a temperature sensor 61 that measures the temperature of the food 81, a storage unit 62 that stores the measurement result of the temperature sensor 61, and a measurement result stored in the storage unit 62. The transmitting unit 63 includes a receiving unit 64 that receives a control signal, an antenna 65 that transmits and receives radio waves, and a power source unit 66 that receives the radio waves received by the antenna 65 and generates power.

  The main body control unit 70 includes the above-described transmission / reception unit 71 and the main body substrate 72. The transmission / reception unit 71 transmits and receives radio waves to and from the RFID tag 60 and signals via the antenna 71a. The transmission / reception part 71b which transmits / receives is provided. Furthermore, the main body substrate 72 includes a microcomputer 72a that receives a reception signal from the transmission / reception unit 71b and transmits a control signal to the transmission / reception unit 71b.

  Next, the operation of the present embodiment will be described. As shown in FIGS. 9 and 10, the temperature of the food 81 is constantly measured by the temperature sensor 61 of the RFID tag 60 that is in direct contact, and the measurement results are sequentially accumulated in the storage unit 62. Here, when the supercooled storage control is performed, a control signal for detecting the current temperature of the food 81 is transmitted from the microcomputer 72a to the transmission / reception unit 71b, and transmitted from the transmission / reception unit 71b to the RFID tag 60 via the antenna 71a. Is done. In the RFID tag 60, the control signal is received by the receiving unit 64 via the antenna 65, the measurement result of the current temperature of the food 81 is read from the storage unit 62, and is transmitted from the transmitting unit 63 to the transmission / reception unit 71 via the antenna 65. Sent. The measurement result received by the transmission / reception unit 71b of the transmission / reception unit 71 is transmitted to the microcomputer 72a via the antenna 71a, and the microcomputer 72a performs supercooled storage control based on the current temperature of the food 81.

  Here, since the RFID tag 60 is incorporated in the bottom surface of the housing case 201, the temperature of the food 81 placed on the bottom surface of the housing case 201 can be measured by making almost direct contact, and the temperature can be measured with high accuracy. It can be performed. Further, since the RFID tag 60 performs wireless communication and generates electric power by receiving radio waves, a signal line and an electric wire between the RFID tag 60 and the refrigerator 1 body are not necessary. For this reason, since the situation where the signal line or electric wire of the RFID tag 60 incorporated in the bottom surface of the storage case 201 does not obstruct will not occur, it becomes easy to remove the storage case 201 from the refrigerator 1 main body and clean it.

The food 81 may be placed on the food 80 containing the RFID tag 60 or placed on the bottom surface of the housing case 201 and placed on the RFID tag 60. According to such a method of use, the temperature of the food 81 can be measured with high accuracy by being brought into almost direct contact.
Further, a plurality of RFID tags 60 may be incorporated in a sheet, and this sheet may be laid on the bottom surface of the housing case 201. Also in this case, by placing the food 81 on the RFID tag 60, it is possible to measure the temperature of the food 81 with high accuracy by making the temperature of the food 81 almost directly contact. Moreover, since a sheet | seat can be easily removed from the storage case 201, the storage case 201 and a sheet | seat can be wash | cleaned separately, and cleaning property improves further.

Embodiment 3 FIG.
Next, a refrigerator that is an example of a cryopreservation device according to Embodiment 3 will be described. FIG. 11 is a cross-sectional view showing a side structure of freezer compartment 200 according to the present embodiment. The third embodiment is different from the second embodiment in that a food tray (temperature measuring means) 75 disposed on the bottom surface of the housing case 201 is provided instead of the RFID tag 60. Other configurations are the same as or equivalent to those of the second embodiment. In addition, the same code | symbol is attached | subjected about the component which is the same as that of Embodiment 2, or equivalent, and the description is abbreviate | omitted.

  As shown in FIG. 11, a food tray 75 is disposed on the bottom surface of the storage case 201. As shown in FIGS. 12 and 13, the food tray 75 incorporates an RFID tag 76 that incorporates a temperature sensor 76 a disposed on the upper surface side and a weight sensor 76 b disposed on the rear surface side. Further, leg portions 75a are attached to the back surface of the food tray 75 so as not to wobble due to the protrusion of the weight sensor 76b. In addition to the temperature sensor 76a and the weight sensor 76b, the RFID tag 76 includes a storage unit 76c that stores the measurement results of the temperature sensor 76a and the weight sensor 76b, a transmission unit 76d that transmits the measurement results stored in the storage unit 76c, and a control. A receiving unit 76e that receives a signal, an antenna 76f that transmits and receives radio waves, and a power source unit 76g that receives the radio waves received by the antenna 76f and generates power.

  Next, the operation of the present embodiment will be described. As shown in FIGS. 12 and 13, the temperature of the food 81 is constantly measured by the temperature sensor 76a of the RFID tag 76 that is in direct contact, and the measurement results are sequentially stored in the storage unit 76c. The weight of the food 81 is measured by the weight sensor 76b of the RFID tag 76, and the measurement result is accumulated in the storage unit 76c. Here, when controlling the supercooled storage, when a control signal for detecting the current temperature and weight of the food 81 is transmitted from the main body control unit 70, the RFID tag 76a receives the reception unit 76e via the antenna 76f. A control signal is received at. Based on this control signal, the current temperature measurement result and the weight measurement result of the food 81 are read from the storage unit 76c and transmitted from the transmission unit 76d to the transmission / reception unit 71 via the antenna 76f. Based on the measurement result received by the transmission / reception unit 71, the main body control unit 70 performs supercooled storage control based on the current temperature and weight of the food 81.

  As described above, according to the present embodiment, since the supercooled storage control is performed based on the current temperature and weight of the food 81, the supercooled storage suitable for the amount of food can be controlled, and the storage quality can be controlled. Will improve.

In Embodiments 1 to 3 described above, the refrigerator is described as an example of the cryopreservation device. However, the cryopreservation device is not limited to the refrigerator, and any one that can be stored frozen, such as a freezer or a freezer container. It may be a device.
In the first to third embodiments, the temperature variation range based on the temperature information measured by the temperature sensor 50b of the temperature measurement member 50, the temperature sensor 61 of the RFID tag 60, the temperature sensor 76a of the food tray 75, and the like. You may provide the secular change recording means which records a secular change, and the aged deterioration alerting means which alert | reports when it remove | deviates from the initial temperature change range based on the secular change recorded on the secular change recording means.

In this case, since the secular change of the temperature fluctuation range based on the temperature information measured by each temperature sensor 50b, 61, 76a is recorded in the aging change recording means, each current temperature sensor 50b, 61, 76a It is possible to determine whether or not the measured value is out of the initial temperature change range. When each temperature sensor 50b, 61, 76a deteriorates and deviates from the initial temperature change range, the aging deterioration notifying means, for example, a warning based on the aging recorded in the aging change recording means. The user can easily know the maintenance time by notifying by turning on the lamp or the like.
As a result, the user can reliably replace the parts based on the lifetimes of the temperature sensors 50b, 61, and 76a, and can guarantee the quality of the refrigerated storage for a long period.

FIG. 1A is a graph showing a change in temperature when water is frozen without “overcooling”. FIG. 1B is a graph showing a temperature change when water is frozen by “with supercooling”. It is the figure which showed the state of the meat structure | tissue when meat was frozen by normal quick freezing and supercooling freezing, and the meat once frozen was thawed. 3 is a cross-sectional view showing the structure of the refrigerator according to Embodiment 1. FIG. It is sectional drawing which shows the side structure of the freezer compartment which concerns on Embodiment 1. FIG. It is sectional drawing which shows the side structure of the freezer compartment which concerns on Embodiment 1. FIG. It is a perspective view which shows the structure of a temperature measurement member. It is a timing chart which shows the example of supercooling control. It is a perspective view which shows another structure of a temperature measurement member. It is sectional drawing which shows the side structure of the freezer compartment which concerns on Embodiment 2. FIG. It is a block diagram which shows the structure of the RFID tag which concerns on Embodiment 2, and a main body control part. It is sectional drawing which shows the side structure of the freezer compartment which concerns on Embodiment 3. FIG. FIG. 10 is a block diagram illustrating configurations of an RFID tag and a main body control unit according to a third embodiment. It is a side view which shows the structure of the food tray which concerns on Embodiment 3.

  DESCRIPTION OF SYMBOLS 1 Refrigerator, 2 fan, 3 cooler, 4 air path, 5 liquid crystal operation panel, 10 compressor, 41 freezer compartment air path, 42 freezer compartment back upper side outlet, 43 freezer compartment ceiling side outlet, 44 freezer compartment back side suction Port, 45 Freezer compartment bottom suction port, 46 Damper (control means), 50 Temperature measurement member, 50a Temperature sensor base, 50b Temperature sensor, 50c Ventilation hole, 51 Wire, 52 Roller, 53 Winder, 60 RFID tag (temperature) Measuring means), 61 temperature sensor, 62 storage unit, 63 transmission unit, 64 reception unit, 65 antenna, 66 power supply unit, 70 main body control unit, 71 transmission / reception unit, 71a antenna, 71b transmission / reception unit, 72 main body substrate, 72a microcomputer, 75 Food tray (temperature measuring means), 76 RFID tag, 76a Temperature sensor, 76b Weight sensor , 76c Storage unit, 76d Transmitter unit, 76e Receiver unit, 76f Antenna 76f, 76g Power supply unit, 81 Food, 100 refrigerator compartment, 200 freezer compartment, 200a actuator, 200b notification lamp, 201 storage case, 201a bowl-shaped piece, 300 freezer Room, 301 Freezing case, 400 Vegetable room, 401 Vegetable case.

Claims (10)

A freezer room for storing cold food by introducing cold air;
Temperature measuring means for measuring the temperature of the food stored in the freezer;
Control means for adjusting the cold air introduced into the freezer compartment so that the food stored in the freezer compartment is maintained in a supercooled state that does not freeze even at a temperature below the freezing point, based on the measurement result of the temperature measuring means. And
The cryopreservation apparatus, wherein the temperature measuring means is provided so as to be lowered toward the food in the freezer compartment. 2. The cryopreservation apparatus according to claim 1, wherein the cold air inlet into the freezer compartment is provided above the position of the temperature measuring means after descending toward the food. The cryopreservation apparatus according to claim 1 or 2, wherein the temperature measuring means has a flexible sheet shape. The cryopreservation apparatus according to claim 3, wherein the temperature measuring means includes a plurality of vent holes for guiding cold air to food. The cryopreservation apparatus according to claim 3, wherein the temperature measuring means includes a plurality of temperature sensors for measuring the temperature of the food. The control means estimates the amount of food stored in the freezer compartment from outputs of a plurality of temperature sensors provided in the temperature measuring means, and performs temperature control of the freezer compartment based on the amount of food. The cryopreservation device according to claim 5, wherein: The temperature measuring means is lowered when performing control for shifting the food in the freezer compartment to a supercooled state, and is raised when the supercooled state is released. The frozen storage apparatus as described in any one of Claims. The freezing chamber includes a food storage case that is provided so that it can be pulled out and whose upper surface is opened, and a drawer prevention unit that prevents the food storage case from being pulled out while the temperature measuring unit is lowered. The frozen storage device according to any one of claims 1 to 7. The freezer compartment includes a food storage case that is provided so that it can be pulled out and whose upper surface is open, and a notification unit that notifies that the food storage case is not pulled out while the temperature measurement unit is lowered. The cryopreservation device according to any one of claims 1 to 8, wherein Based on the temperature information measured by the temperature measuring means, the secular change recording means for recording the secular change of the temperature fluctuation range;
The aging deterioration notification means for notifying when the temperature change is out of the initial temperature change range based on the aging recorded in the aging recording means. The cryopreservation device according to one item.

Images