JPH0781772B2 - Cold storage - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] Industrial field of use The present invention relates to a low temperature chamber for cooling a storage chamber by indirect cooling.

2. Description of the Related Art A conventional refrigerator box consists of a heat-insulating outer box and a heat-conducting inner box 2
Japanese Utility Model Laid-Open No. 60-93882 discloses a low-temperature warehouse having a heavy structure and a cooling device disposed between the inner and outer boxes to cool the inner box and its interior. On the other hand, JP-A-62-134477 discloses a refrigerator having a vegetable storage container for storing vegetables in a fresh state and cooling the inside of the container by indirect cooling.

In the above-mentioned publication, a heat-insulating outer box and a heat-conducting inner box are fixedly installed with a fixed space, and cold air is circulated in the space between the outer box and the inner box to cool the inner box. The inside is a refrigerating room, the evaporator of the refrigerator for making cold air and the fan for circulating the cold air are placed in the cold air circulation space between the outer and inner boxes, and the set other than the evaporator of the refrigerator is installed. It is disclosed that it is mounted on the outside of the outer box.

On the other hand, in the above-mentioned publication, there is disclosed a refrigerator in which a lid partly or wholly composed of a laminated member having a fiber layer on both outer sides and a resin layer in the middle thereof is provided in close contact with an upper opening of a container. A vegetable storage container is disclosed.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the above-mentioned technique, the inner box is formed of a good conductor of heat, the cooling device is provided in the cold air circulation space between the inner and outer boxes, and Although it is designed to perform indirect cooling, when storing agricultural products such as vegetables and fruits, that is, live food, in the refrigerating chamber formed inside this inner box, the respiration action of the food itself causes When ethylene gas, carbon dioxide, etc. are discharged into the refrigerating compartment, the gas composition in the refrigerating compartment changes, and when the gas composition state that promotes aging of food during storage of agricultural products is reached, the quality of food is likely to deteriorate. Therefore, there is a problem that food cannot be stored for a long period of time.

On the other hand, in the above-mentioned technique, the lid is a flat plate having a large number of through holes made of olefinic thermoplastic resin such as polyethylene, and a moisture permeable film made of a silicone rubber thin film welded to one side of the flat plate. It is composed of a rubber packing made of vinyl chloride or the like arranged on the outer periphery of these to remove the dew condensation water adhering to the lid. There is no problem if the amount A to be evaporated is larger than the amount B evaporated from vegetables, but if A is smaller than B, condensed water still drops from the lid into the vegetable storage container and collects at the bottom of the container. However, there is a problem that the vegetables are damaged and the inner surface of the vegetable container becomes slimy, which makes the vegetables unsanitary for storage. Further, the moisture permeable membrane could not adsorb ethylene gas discharged from the vegetables into the container.

Therefore, the present invention provides a low-temperature cabinet configured to cool a storage room by indirect cooling and suppress deterioration of quality of living foods such as vegetables and fruits for long-term storage. .

[Means for Solving the Problems] The present invention relates to a heat-insulating outer box, a heat-conducting inner box that is provided inside the outer box with a space therebetween to form a storage chamber, and an outer box. Provided is a low-temperature chamber that is provided in a circulation space formed between a box and an inner box and includes a cooler and a cooling device having a blower, and cools the inner box to indirectly cool a storage chamber. Is something that
A gas adsorbing member for adsorbing ethylene gas in the storage chamber, which is disposed in the inner box so as to expose one surface to the storage chamber and the other surface to the circulation space, and a heating member for heating the gas adsorbing member, The ethylene gas adsorbed by the gas adsorbing member can be removed from the adsorbing member.

In addition, a heat-insulating outer box, a heat-conducting inner box that is arranged inside the outer box with a space to form a storage chamber, and a circulation space formed between the outer box and the inner box. In a low-temperature cabinet that is provided with a cooler and a cooling device having a blower, and cools the inner box to indirectly cool the storage chamber, one surface is exposed to the storage room and the other surface is used as a circulation space. A gas adsorbing member for adsorbing ethylene gas in the storage chamber, which is disposed in the inner box so as to be exposed, an opening for communicating the circulation space with the outside, and a damper device for opening and closing the opening are provided. The ethylene gas released into the circulation space may be forcibly discharged to the outside of the low temperature chamber.

By the gas adsorbing member arranged in the inner box of good heat conduction, ethylene gas generated from the food stored in the storage chamber is gradually adsorbed and a part of the ethylene gas is discharged into the circulation space.
It acts to reduce the ethylene gas concentration in the storage chamber and slow the rate of change of gas composition.

Also, by providing a heating device and performing a heating operation,
The surface of the gas adsorbing member is heated so that the adsorbed ethylene gas is gradually introduced into the circulation space from the adsorbing member, and the heating member acts as an activating member for removing ethylene gas from the adsorbing member.

On the other hand, ethylene gas is released from the gas adsorbing member into the circulation space, and the gas composition in the circulation space changes (especially, the concentration of ethylene gas increases). On the other hand, while the forced air is discharged, fresh air is introduced into the circulation space to replace the air in the circulation space and suppress the increase in ethylene gas concentration.

Embodiments Embodiments of the present invention will be described below with reference to FIGS.

Reference numeral 1 denotes a low-temperature refrigerator such as a prefabricated refrigerator, which is a heat-insulating outer box 2 in which a heat-insulating panel is combined to form a box, and the outer box 2
Inner box 3 made of good heat conductor such as metal with a space inside
That is, it includes a closed storage chamber 10 formed by arranging the top wall 3A, the bottom wall 3B, and the front, rear, left, and right side walls 3C to 3F, and a cold air circulation space 11 formed around the storage chamber 10. There is. In addition, the front wall of the heat-insulating outer box 2 has an opening 7 for loading and unloading stored foods (in this example, agricultural products such as vegetables and fruits) and an opening 7 for opening and closing the opening 7, and the storage room 10 is closed. A heat insulating door 8 is provided.

On the ceiling wall 3A forming the cold air circulation space 11, a cooler represented by an evaporator forming a part of the refrigeration cycle.
12, an air blower 13 including an air blower fan and an air blower fan motor, and a cooling device 1 inside the refrigerator having a defrosting heater 12A
4 is provided, and the bottom of the cooling device 14 (which is usually provided with a dew tray for receiving dew generated during defrosting of the cooler 12) penetrates the ceiling wall 3A to form the storage chamber 10. Drainage device such as drainage pipe with a heater so that it can be led out to the outside of the heat insulation outer box 2
15 are connected together. Reference numerals 16 and 17 denote front and rear partition plates that partition the inside of the upper space 11A, which will be described later, into a blowing side and a suction side.
In the present embodiment, as the cooling device 14, the temperature control range is usually centered at 0 ° C. and the temperature control range is small, and the temperature control is performed with an extremely high control accuracy (for example, control accuracy of set temperature ± 0.5 ° C.). The thing is adopted. The ice temperature refers to the temperature zone between 0 ° C at which water freezes and the temperature immediately before freezing of food, and is intended for long-term storage while avoiding physical property changes (cell destruction, etc.) due to freezing of food. It can be said to be the temperature.

The cold air circulation space 11 includes an upper space 11A as a first space above the ceiling wall 3A, a bottom space 11B as a second space below the bottom wall 3B, and a front space as a third space outside the front side wall 3C. 1
1C and rear space 11D as the fourth space outside the rear wall 3D
And the left side space 11E as the fifth space outside the left side wall 3E
And a right side space 11F as a sixth space on the outer side of the right side wall 3F. In this example, the cooling device 14 is connected to the upper space 11F.
It is placed in A. The air cooled through the cooling device 14 (hereinafter referred to as “cool air”) passes from the upper space 11A through the front and rear right spaces 11C, 11D, 11F to the bottom space 11B and is returned to the cooling device 14 through the left space 11E. Take a route. At this time, the cold air cools each of the upper, lower, front, rear, left and right walls 3A to 3F, and indirectly cools the inside of the storage chamber 10 by heat transfer from each wall surface (hereinafter, this is referred to as indirect cooling).

Side walls forming a part of the inner box 3, for example, rear left and right side walls 3D to 3F
A gas adsorbing member 20 for adsorbing ethylene gas generated by breathing of agricultural products is provided in the container. In order to expose one surface of the gas adsorption member 20 to the storage chamber and expose the other surface to the cold air circulation space 11, the adsorption member 20
One side of the holder 22 for holding the inside of the inner box 3 is opened, and a large number of holes 25 are formed on the other side. Further, it is desirable that the holder placement sites on the rear left and right side walls 3D to 3F be largely opened. That is, the other surface of the gas adsorption member 20 is exposed to the cold air circulation space 11 through the hole 25. further,
As the gas adsorbing member 20, a gas-selective permeable composite plate material composed of a green tuff containing zeolite and a polyethylene film is used. In addition, green tuff has specific gas adsorption / permeation performance (especially excellent in adsorbing ethylene gas), and this green tuff is docked with a polyethylene film having moisture permeability to produce agricultural products. Ethylene gas, which is an aging-promoting hormone generated by respiration, is rapidly removed, and it has been completed as a member having low moisture permeability.

Reference numeral 30 denotes a heating device such as a heater for heating the gas adsorbing member 20 to easily release the adsorbed ethylene gas, and at a position where the surface of the gas adsorbing member 20 on the cold air circulation space side can be heated, for example, the upper space 11A is arranged. There is. Further, the heating device 30 is to be operated periodically, and the heating operation control means 33 such as a gas concentration detector for detecting the ethylene gas concentration in the cold air circulation space 11 or a timer device controls the gas adsorbing member 20. The heating device 30 may be operated before reaching the adsorption limit amount.

Reference numeral 40 is an opening for air exchange formed in a proper position of the heat insulating outer box 2, and 41 is a damper device for opening and closing the opening 40. The damper device 41 is operated periodically, and the opening / closing control may be performed by the opening / closing operation control means 44 such as a timer device or an ethylene gas concentration detector.

Since the heating device 30 and the damper device 41 both act so as to increase the air temperature in the cold air circulation space 11 during their operations (during the heating and opening operations),
(I) The cooling is inevitable when the temperature rise is unavoidable (however, it is desirable to operate the blower 13), or (ii) the cooling is performed while both the devices 30 and 41 are operating. To increase the cooling capacity of the device 14,
(Iii) It is desirable to have a control structure that has a protective measure such as operating only when all the agricultural products in the storage room are taken out so as to suppress the temperature rise in the storage room as much as possible.

Let's adopt (i) as an example. When the cooling device 14 stops the cooling operation, that is, when the set temperature is reached and during the defrosting operation, first, the heating device 30 is controlled by the heating operation control means 33.
Is heated for a certain time (for example, 10 minutes). And
After the elapse of a predetermined time (for example, 5 minutes) within a fixed time, the opening / closing operation control means 44 causes the damper device 41 to open. After this, both devices 30 and 41 are operated simultaneously or the latter 4
Delay 1 and return to the normal state.

The cooling of the cold storage 1 in the above configuration will be described.

First, if the storage room 10 in the non-cooled state is filled with food, for example, agricultural products such as vegetables and fruits, and the set temperature is set to 0 ° C. and the cooling device 14 is operated, the storage room 10 is set at a temperature higher than the set temperature. Since the air is also higher, the air cooled by the cooling device 14 (cool air) is cooled by the cold air circulation space 11, that is, the upper space.
Bottom space from 11A through front and rear right spaces 11C, 11D, 11F
Cooling device 14 along the path leading to 11B and passing through left space 11E
Return to.

At this time, the cold air cools the upper, lower, front, rear, left and right walls 3A to 3F, and indirectly cools the inside of the storage chamber 10 by heat transfer from the respective wall surfaces. Due to this indirect cooling, when the temperature in the storage chamber 10 is gradually lowered to a set temperature or lower (specifically, a temperature lower than the set temperature by a certain temperature or lower), the cooling device 14 performs the thermocycle off operation or the minimum capacity. The operation is switched to the latter (in this example, the latter) and the like so that the temperature in the storage chamber is maintained at 0 ° C.

It should be noted that the cooling device 14 stops its cooling operation, the temperature inside the storage chamber rises due to an increase in the cooling load due to external air inflow or disturbance accompanying the opening / closing operation of the heat insulation door 8, and a predetermined temperature higher than the set temperature. When it exceeds, the cooling operation is repeated to maintain the temperature in the storage chamber at the set temperature.

On the other hand, the crops stored in the storage room 10 breathe because they are alive, and because the storage room 10 is closed, the air inside the storage room simply convects naturally, and is generated by the breathing of the crops. The ethylene gas changes the gas composition in the storage chamber 10 (specifically, the component ratio of various gases contained in the air) (that is, the ethylene gas concentration increases). However, the generated ethylene gas is gradually adsorbed by the gas adsorbing member 20 and a part of the ethylene gas is released into the cold air circulation space 11 through the holes 25, so that the ethylene gas concentration is prevented from rapidly increasing. The rate at which the gas composition in the storage chamber changes can be slowed down. Therefore, the deterioration of the quality of agricultural products is suppressed, and the storage period of agricultural products can be extended as compared with the conventional low-temperature storage. In this example,
Since the indirect cooling is performed, in addition to maintaining the storage chamber at a constant temperature and high humidity, it is possible to slow the rate of change of the gas composition of the air in the storage chamber, suppress aging of crops, and extend the cold storage period.

Further, by providing the heating device 30 and operating the heating device 30, the ethylene gas adsorbed by the gas adsorbing member 20 is forcibly released while creating an environment in which the ethylene gas is easily released into the cold air circulation space 11. It is possible to activate the gas adsorbing member 20 by this release, and suppress the deterioration of the adsorbing ability. Further, since the heating device 30 is regularly operated, the gas adsorbing member 20 can be activated regularly, the saturation of the adsorbing performance of the adsorbing member 20 is suppressed, and the cooling operation of the low temperature warehouse 1 is performed. This is particularly effective when the control is carried out over a long period of time, and the shelf life of agricultural products can be further extended.

By disposing the damper device 41 and opening the damper device 41, the air in the cold air circulation space 11 in which the ethylene gas concentration is increasing is discharged to the outside, while fresh external air is taken in and the cold air circulation space 11 is taken in. By replacing the internal air with the external air, ethylene gas can be easily discharged from the gas adsorbing member to the cold air circulation space, and the deterioration of the adsorbing ability of the gas adsorbing member can be suppressed.

[Effects of the Invention] As described in detail above, according to the present invention, the gas composition in the storage chamber changes due to ethylene gas generated by the respiratory action of the agricultural products stored in the storage chamber, but the gas adsorption in the inner box Since the member is provided, the generated ethylene gas can be gradually adsorbed by the gas adsorbing member and a part of the ethylene gas can be released into the cold air circulation space. Therefore, it is possible to slow down the rate of change of the gas composition in the storage chamber, suppress the aging of agricultural products, and prolong the storage period of agricultural products as compared with the conventional low-temperature storage.

In addition, since it performs indirect cooling, in addition to slowing the rate of change of the gas composition of the air in the storage room, it is possible to maintain a constant temperature and high humidity inside the storage room, and avoid blowing cold air directly on the produce. It is possible to extend the cold storage period while suppressing the aging.

Further, by providing a heating device and operating the heating device, it is possible to create an environment in which the ethylene gas adsorbed by the gas adsorbing member is easily released into the cold air circulation space and to forcefully release it. This release activates the gas adsorbing member and suppresses a decrease in adsorption capacity.

By disposing a damper device and opening the damper device, the air in the cold air circulation space where the ethylene gas concentration is increasing is replaced with fresh external air to clean the air in the cold air circulation space. By doing so, the ethylene gas can be easily released from the gas adsorbing member to the cold air circulation space, and the deterioration of the adsorbing ability of the gas adsorbing member can be suppressed.

[Brief description of drawings]

Each drawing shows one embodiment of the present invention, FIG. 1 is a front view of a low temperature chamber in a partially cutaway state showing a cold air circulation path during cooling, and FIG. 2 is a cross section taken in a cold air circulation space to remove a ceiling wall. FIG. 3 is an enlarged view of part A in FIG. 1 ... Low temperature chamber, 2 ... Insulated outer box, 3 ... Inner box, 10 ... Storage room, 11 ... Cold air circulation space, 14 ... Cooling device, 20 ... Gas adsorption member, 30 ... Heating device , 40 …… Aperture, 41 …… Damper device.

Claims (2)

[Claims] 1. A heat-insulating outer box, a heat-conducting inner box which is arranged inside the outer box with a space therebetween to form a storage chamber, and is formed between the outer box and the inner box. In a low-temperature warehouse, which is provided with a cooler and a cooling device having a blower arranged in a circulation space that cools the inner box to indirectly cool the storage chamber,
A gas adsorbing member for adsorbing ethylene gas in the storage chamber, which is disposed in the inner box so that one surface is exposed to the storage chamber and the other surface is exposed to the circulation space, and a heating member for heating the gas adsorbing member. And a low temperature refrigerator. 2. A heat-insulating outer box, a heat-conducting inner box which is disposed inside the outer box with a space to form a storage chamber therein, and is formed between the outer box and the inner box. In a low-temperature warehouse, which is provided with a cooler and a cooling device having a blower arranged in a circulation space that cools the inner box to indirectly cool the storage chamber,
A gas adsorbing member, which is disposed in the inner box so as to expose one surface to the storage chamber and the other surface to the circulation space and adsorbs ethylene gas in the storage chamber, communicates the circulation space with the outside. A low-temperature storage, comprising: an opening; and a damper device that opens and closes the opening.