JPH0536710B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a double vacuum storage device for storing raw food products such as fruits and vegetables and other raw materials at low temperature and low pressure. It is.

[Prior Art] Japanese Patent Application No. 59-38654 describes a vacuum storage method in which stored materials are left in a windless state under conditions of reduced pressure, low temperature, high humidity, and atmospheric gas that suppresses growth. As shown in the figure, an inner chamber C is provided inside the outer chamber A for storing stored items, leaving a cold air circulation space B around the outer chamber A, which has a vacuum-resistant structure with cold insulation properties. A refrigerant pipe E and a fan F for circulating cold air are connected to the refrigerator D, and a refrigerant pipe E and a fan F for circulating cold air are installed in the interior chamber C to maintain the optimal pressure, temperature, humidity, and atmospheric gas condition depending on the stored items, and to A double vacuum storage container has been proposed that maintains the interior of the container in a windless state.

[Problems to be Solved by the Invention] By the way, in such conventionally proposed dual-type vacuum storage devices, the temperature inside the inner chamber where stored items are stored is several times lower than that inside the cold air circulation passage due to the respiratory heat of the stored items. The temperature becomes high. Therefore, the temperature of the humidifying water in contact with the cold air circulation passage becomes lower than the temperature inside the interior chamber, and the interior of the interior chamber is not sufficiently humidified, causing the stored items to dry locally. In order to prevent this drying, if the water for humidification is heated to a temperature equal to or higher than the temperature inside the interior chamber, or if other humidification means are used to humidify, condensation will occur on the inner wall surface of the interior chamber that is in contact with the cold air circulation passage. In particular, water droplets that have condensed on the ceiling fall onto the stored items, causing them to rot.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a double vacuum storage device that is free from the problems of dryness and dew condensation caused by temperature differences between the outer and inner chambers.

[Means for Solving the Problems] In order to achieve the above object, the double vacuum storage device according to the present invention includes an outer chamber having a cold insulation and vacuum-resistant structure, and an outer chamber disposed within the outer chamber, A space formed between the outer chamber and the inner chamber, the space having at least one inner chamber for vacuum storage made of a material that can withstand the differential pressure under storage conditions and has good heat conductivity. In addition to circulating cold air under reduced pressure, the inside of the interior is kept at high humidity using humidifying means, and the opening ratio is 5 to 20% of the ceiling area in the ceiling wall portion of the interior that comes into contact with the circulating cold air in the above-mentioned space. By appropriately distributing a large number of holes, the humidity inside the interior room can be adjusted to 90-100% R.
It is characterized by maintaining H.

[Function] In the double-type vacuum storage device according to the present invention configured as described above, the inner chamber wall is cooled by the cold air circulating between the outer chamber and the inner chamber, and the humidity near the wall surface becomes supersaturated, causing dew condensation. However, in the ceiling of the interior room, a gas flow occurs between the inside and outside of the interior room through a large number of openings, eliminating the temperature difference near the inside and outside surfaces of the ceiling, and reducing the humidity near the ceiling. There is no oversaturation and no condensation on the inner walls of the ceiling. In other words, the above effect can only be obtained by setting the opening ratio of the large number of holes provided in the ceiling of the interior room to a range of 5 to 20% of the ceiling area, and the opening ratio is 5% or less of the ceiling area. If this is the case, the temperature difference between the inside and outside surfaces of the ceiling cannot be eliminated, so condensation will occur on the ceiling, and water droplets will fall onto the stored items, causing them to rot. If it is more than 20% of the area, there will be no condensation on the ceiling, but there will be a substantial flow of atmosphere into the interior room through each hole, which will reduce the humidity inside the interior room and prevent stored items placed inside the interior room. will be dried.
Therefore, in the present invention, by setting the opening ratio of the large number of holes in the range of 5 to 20% of the ceiling area, it is possible to maintain the humidity in the interior room at 90 to 100% RH and prevent dew condensation on the ceiling. It is possible to solve the problem of dryness and condensation caused by the temperature difference between the outside room and the inside room.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to FIG. 1 of the accompanying drawings.

FIG. 1 schematically shows an embodiment of a double vacuum storage device according to the present invention. It is an outer chamber made of concrete or iron whose outer periphery is covered with a cold insulation material, and an inner chamber 3 for storing stored items is provided inside the outer chamber, leaving a cold air circulation passage 2 around it. Also arranged within the outer chamber 1 are refrigerant pipes 5 connected to a suitable refrigerator 4 and a fan 6 for circulating cold air. The inner chamber 3 is made of a material with good heat conductivity, is designed to withstand the pressure difference between the pressure in the outer chamber 1 and the pressure in the inner chamber 3 under equilibrium conditions of storage, and is designed to withstand the pressure difference between the pressure in the outer chamber 1 and the pressure in the inner chamber 3, and to Depending on the scale of the device, one or more may be provided, or the interior may have a multi-chamber structure. 7 is water for humidification, which is placed in the bottom of the outer chamber 1, and this water 7 for humidification is heated to a temperature of about 0 to 10 degrees Celsius depending on the temperature inside the inner chamber 3 by means of an appropriate heating means (not shown). heated to temperature. Thereby, the humidity within the interior chamber 3 can be maintained at 90-100% RH.

As shown in the enlarged view in Fig. 2, the ceiling part 8 of the interior room 3 has a large number of holes 9 drilled at appropriate intervals with an opening ratio of about 6%. can be appropriately set depending on the size of the device, operating conditions, etc.

Although not shown in the drawings, the outer chamber 1 is connected to a decompression pump, and the inner chamber 3 includes a humidifier (e.g., steam generation means) and a gas introduction means for maintaining the storage atmosphere in a desired state. It is also combined with an exhaust port for a vacuum pump. Naturally, the outer room 1 and the inner room 3 are provided with an opening/closing section for bringing in and taking out stored items, and the outer room 1
Control of storage conditions such as cold air circulation and pressure regulation within the container can be carried out automatically or manually by suitable control means.

In the operation of the apparatus of the illustrated embodiment constructed in this manner, the apparatus is controlled to store the stored material under conditions of reduced pressure, low temperature, high humidity, and growth-inhibiting atmospheric gas suitable for the stored material. Ru. The inside of the cold air circulation passage 2 formed between the outer chamber 1 and the inner chamber 3 is maintained at a pressure of approximately 0.8×10 ⁴ Pa to 3.0×10 ⁴ Pa, and is maintained by the action of the refrigerant pipe 5 and the cold air circulation fan 6. The cool air is then circulated. This cold air cools the wall surface of the interior room 3, and the humidity near the wall surface becomes supersaturated, causing dew condensation.
, a gas flow occurs through a large number of holes 9, and the water vapor inside the ceiling part 8 flows into the cold air circulation passage 2.
As well as leaking inward, there is no temperature difference between the inside and outside of the ceiling section 8, so oversaturation and condensation near the ceiling section 8 can be prevented. In this case, the flow of gas through the holes 9 in the ceiling part 8 is only slight and the store can be kept essentially airless.

Naturally, the present invention can also be applied to an apparatus having the structure shown in FIG.
Maintain at RH.

[Effects of the Invention] As explained above, in the vacuum storage device according to the present invention, there is an outer chamber having a structure that is cold and insulating and can withstand vacuum, and an outer chamber that is arranged within the outer chamber and that is compatible with the storage conditions of the outer chamber. and at least one vacuum storage inner chamber made of a material that can withstand differential pressure and has good heat conductivity, and circulates cold air under reduced pressure into the space formed between the outer chamber and the inner chamber. The interior of the interior is made highly humid by a humidifying means, and the ceiling wall portion of the interior that comes into contact with the circulating cold air in the above-mentioned space has an opening ratio of 5 to 50% of the ceiling area.
20% RH, and is configured to maintain the humidity inside the inner chamber at 90 to 100% RH, creating a substantial atmosphere that dries the stored items inside the inner chamber. It is possible to prevent condensation from forming on the ceiling due to temperature differences and supersaturation of humidity without causing a flow of moisture, and also prevent uneven humidity from occurring due to the heat of breathing of stored items, thereby preventing drying and spoilage of stored items. can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention;
FIG. 2 is an enlarged view of a part of the apparatus shown in FIG. 1, and FIG. 3 is a schematic sectional view showing an example of a dual vacuum storage apparatus using a conventional reduced pressure storage method. In the figure, 1...outer room, 2...cold air circulation passage, 3...
...Inner room, 4...Freezer, 5...Refrigerant pipe, 6...Cold air circulation fan, 7...Water for humidification, 8...Ceiling part, 9...Hole.

Claims (1)

[Claims] 1. An outer chamber having a structure that is cold and insulating and can withstand vacuum; and at least one vacuum storage inner chamber disposed within the outer chamber and made of a material that can withstand differential pressure under storage conditions with the outer chamber and has good heat conductivity. In the vacuum storage device, the vacuum storage device has a chamber, and circulates cold air under reduced pressure in the space formed between the outer chamber and the inner chamber, and maintains the inner chamber at high humidity by humidifying means. In the ceiling wall part of the interior room that comes into contact with the circulating cold air in the air space,
A double vacuum storage device characterized in that a large number of holes are appropriately distributed and provided with an opening ratio of 5 to 20% of the ceiling area.