JPH0433226Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention mainly relates to packaging boxes for pre-cooling and shipping vegetables. [Conventional technology and its problems] In general, when shipping and transporting raw vegetables such as strawberries, carrots, lettuce, spinach, and broccoli to long distances, these vegetables are stored in insulated shipping packaging boxes. In this state, precooling is performed by vacuum cooling or differential pressure cooling. Precooling of vegetables by vacuum cooling as described above differs depending on the type of vegetable, but for example, in the case of strawberries, the atmosphere in the cooling chamber is gradually depressurized from a normal pressure of 760 mmHg over a period of about 8 to 10 minutes. Finally, the pressure is reduced to about 30 mmHg, and the cooling temperature is reduced to 1 to 2 degrees Celsius.
This state is maintained and cooled for about 15 to 20 minutes, and after this cooling, the pressure is returned to normal pressure within a very short period of 2 to 3 minutes or less. Also, in the case of relatively hard vegetables such as carrots, the cooling time in the vacuum state is increased. As packaging boxes for pre-cooling and shipping the vegetables mentioned above, they have insulation properties to keep them cold, and at the same time,
During the pre-cooling described above, it is necessary to be able to cope with the pressure reduction action in the box containing the vegetables and the pressure increase action to return the pressure to normal pressure. Conventionally, packaging boxes for pre-cooling and shipping these types of vegetables have been made of molded plastic containers, which require a large amount of space to transport, store, and otherwise handle the empty containers when not in use. As a result, transportation and storage efficiency is reduced, so cardboard boxes are often used, which have appropriate insulation properties and can be folded low when not in use. However, if the upper part is kept closed by the inner and outer flaps during the precooling operation, it will not be possible to cope with the pressure reduction and pressure increase effects during vacuum precooling, and the precooling time will become longer. In addition, due to the heat insulation and CA effects, flexural deformation occurs in corrugated cardboard with composite plastic sheets, so normally, as shown in Fig. 6, An opening 4' is provided in the hole 4' to cope with pressure reduction and pressure increase during pre-cooling. [Problem to be solved] However, providing a simple opening 4' in the side wall plate 1' will not only cause the temperature inside the box to rise quickly after pre-cooling, causing moisture in the vegetables to evaporate, but also to provide a CA effect. become unable. In order to prevent this, it is extremely troublesome to close the openings with adhesive tape or the like after pre-cooling, and the appearance is also unsightly. Incidentally, the present applicant provided a ventilation hole in the upper lid, attached an elastic plate to the outside of the ventilation hole, and made it possible to open and close the ventilation hole by utilizing the elastic deformation of the elastic plate. However, all of these proposals involve containers made of synthetic resin foam; Not only can this not be used on the top surface of cardboard boxes, etc.
In particular, when a plurality of cardboard boxes are stacked, the ventilation holes are blocked, making it impossible to ensure ventilation for pressure reduction and pressure increase. In view of the above, the present invention was developed mainly when using a box body that can be folded low when not in use, such as a cardboard box, as a packaging box for precooling and shipping vegetables. It can handle both pressure reduction and pressure increase actions, and can be pre-cooled by vacuum cooling with the lid closed without flexing the side walls.It also has ventilation that can handle both pressure reduction and pressure rise actions even when boxes are stacked directly on top of each other. The purpose is to provide a packaging box with a structure. [Means for Solving the Problems] The packaging box of the present invention that solves the above problems is made of an assembleable box body such as a cardboard box, and has an overlapping portion of inside and outside flaps connected to the upper end of the side wall plate. The inner flap is provided with a ventilation hole that communicates with the inside and outside, and a closing sheet made of an elastic material thinner than the thickness of the outer flap and having a slit that can be opened by elastic deformation closes the ventilation hole. The closure sheet is attached to the outside of the box body, and the corresponding outer flap is provided with a cutout that is wide enough to accommodate the closure sheet and opens to the side of the box body. [Function] According to the present invention having the above configuration, the box can be folded into a bulky and flat shape when not in use for storage, transportation, etc., and can be assembled and used when used. Then, vegetables are stored in the assembled box body, and the upper inner and outer flaps are folded inward to overlap and close the lid. In this state, the portion of the vent hole in the inner flap corresponds to the notch in the outer flap, and the closing sheet attached to the outside of the vent hole is located within the notch and exposed. In particular, since the closing sheet is thinner than the outer flap, even when the boxes are directly stacked, there is a slight gap between the closing sheet and the bottom of the upper box. For example, during precooling by vacuum cooling, as the pressure inside the cooling chamber is reduced to a low pressure, the closing sheet that closes the ventilation holes is bent outward against the elastic force due to the internal pressure, and the The slits in the closing sheet become slightly opened due to the bending and deformation. As a result, the air inside the box is discharged from the slit, and the pressure inside the box is quickly brought to the same pressure as that of the cooling chamber, thereby reducing the pressure to a vacuum. In particular, even if the boxes are stacked in multiple stages, there is a gap between the closing sheet and the bottom of the upper box,
Since the notch opens to the side of the box body, the slit of the closing sheet opens due to bending deformation, and the air discharged from this slit portion can flow out to the outside of the box body, resulting in a decompression effect. I can handle it.
When the inside of the box has approximately the same pressure as the cooling chamber, the closing sheet returns to its original state due to the elastic force of the material, and the slits come into contact with each other to close the ventilation holes. When the pressure is increased after cooling, a pressure difference is created between the inside of the vacuum box and the outside due to the short-time sudden pressure increase, and when the closing sheet made of the elastic body is sucked inward, the air vents are closed. The space causes the sheet to bend inward against the elastic force, thereby causing the slit in the closing sheet to open slightly. Therefore, external air flows into the inside of the closing sheet from this slit portion, and the pressure difference between the inside and outside of the box does not increase any further, and excessive bending and deformation of the box body is prevented.
Further, as the pressure approaches normal pressure, the pressure difference between the inside and outside of the box becomes smaller, and the closing sheet returns to its normal closed state. [Example] Next, an example of the present invention will be described based on the drawings. In FIGS. 1 to 5, A indicates a box body such as a cardboard box that can be assembled, and the lower end of the side wall plate 1 which is connected in a rectangular shape and can be folded flatly has inner and outer flaps 2a, 2b forming the bottom part 2. are arranged in succession on each side, and inner and outer flaps 3a, 3b constituting the lid part 3 on the upper surface are arranged in succession on each side at the upper end. Normally, the inner flaps 2a and 3a are provided on the short side of the side wall plate 1.
Outer flaps 2b, 3b are provided on the long sides of the side wall plate 1, and the ends of the outer flaps 2b, 3b are provided so as to be butted against each other. And the inner and outer flaps 3 at the top of the box A above.
A ventilation hole 4 passing through the inner flap 3a and communicating with the inside and outside is formed by punching or the like at a suitable location in the inner flap 3a at the overlapping portion of the flaps 3a and 3b. This ventilation hole 4
The opening diameter and hole shape can be appropriately determined in consideration of air permeability and elastic deformability of the closing sheet, which will be described later. Reference numeral 5 designates a closing sheet made of rubber, soft synthetic resin such as polyethylene resin foam, or other elastic material, which is slightly thinner than the outer flap 3b of the box body A. The ventilation hole 4 is formed with a large circumference.
The peripheral edge portion 5a is attached to the outside so as to close it, and the inner portion is provided so as to be elastically deformable inward and outward. Although it is possible to attach it by means of adhesive or the like at one or several places on the peripheral edge 5a, it is preferable to attach it by adhesive over the entire circumference as described above in terms of sealability and strength during normal use. A slit 6 is provided in the inner portion of the closing sheet 5, which can be slightly opened by elastic deformation inward and outward. The slit 6 may be formed by forming a linear cut into a cross shape as shown in the figure, or may be formed by one or more cuts in the shape of a single letter or zigzag, etc. In normal conditions, the slit 6 is in a closed state and elastically deforms. It can be implemented in various forms that can be slightly opened. The closing sheet 5 can be attached by adhesion using an adhesive or an adhesive tape, or as long as the slits 6 of the closing sheet 5 can be opened and closed by the elastic deformation of the material. Other fastening means such as fasteners are possible. In addition, the outer flap 3b has inner and outer flaps 3a,
A cutout 7 is provided at a location corresponding to the ventilation hole 4 and the closure sheet 5 in the stacked state of the panels 3b, into which the closure sheet 5 is accommodated and which opens to the side of the box body. The shape of the cutout 7 may be any shape as long as the closure sheet 5 is accommodated therein and the cutout 7 has a portion that opens to the side of the box body. The above-mentioned ventilation structure using the ventilation hole 4, the blocking sheet 5, and the notch 7 can be provided in one place at the overlapping part of the inner and outer flaps 3a and 3b on the upper part of the box body A as shown in the figure, or in multiple places. Sometimes it is kept. The box A may be a normal cardboard box made of single-sided corrugated cardboard, double-sided corrugated cardboard, multi-sided corrugated cardboard, etc., as shown in the figure.
A synthetic resin foam sheet 11a having appropriate rigidity, such as a styrene resin foam sheet, is laminated with one to several sheets of ordinary stepped paper 11b to form a core 11, and surface liner papers 12, 12 are laminated to this core 11. The container is constructed so that it can be assembled in the same way as a corrugated box, using a sheet material that has a certain thickness, stiffness, and heat insulating properties, such as a laminated material made by gluing together one-sided corrugated cardboard or double-sided corrugated cardboard and the foamed sheet. It can be a box. In particular, when the foam sheets 11a described above are laminated, the heat insulation properties are further improved. The packaging box configured as described above is used for pre-cooling and shipping pre-chilled vegetables.Until it is actually used, it is folded into a low volume like a normal cardboard box.
A and 2b constitute the bottom part 2 and are assembled and used. Then, during vacuum precooling, differential pressure precooling, etc., vegetables B such as strawberries, spinach, and lettuce are stored in the box body A, and the top inner and outer flaps 3a and 3b are bent inward and the lid is closed. At this time, the portion of the ventilation hole 4 provided in the inner flap 3a corresponds to the notch 7 of the outer flap 3b, and the closing sheet 5 attached to the outside of the ventilation hole 4 is positioned within the notch 7 and exposed. In this state, they are carried into a cooling chamber and placed side by side or stacked in layers as shown in FIG. For example, in vacuum cooling, a closing sheet 5 is provided to close the ventilation hole 4 of the inner flap 3a as the pressure inside the cooling chamber is reduced to create a low-pressure vacuum.
is bent outward against the elastic force due to the internal pressure, and as shown in FIG. 4, the slit 6 in the closing sheet 5 becomes slightly opened due to the bending deformation. As a result, the air inside the box A flows through the slit 6.
The inside of the box is quickly brought to the same pressure as the cooling chamber, and the pressure is reduced to a vacuum. In particular, even if box A is stacked in multiple tiers,
Since the closing sheet 5 is thinner than the thickness of the outer flap 3b, there is a slight gap between the closing sheet 5 and the bottom surface of the upper box body A, and the notch 7 opens to the side of the box body. Therefore, the air discharged from the slit 6 flows out from the space between the closing sheet 5 and the bottom of the upper box body. Thereafter, as the inside of the box reaches approximately the same pressure as the cooling chamber, the closing sheet 5 returns to the state of closing the ventilation hole 4 due to the elastic force of the material. In this way, the reduced pressure and vacuum state is maintained at a predetermined cooling temperature, and cooling is performed for a certain period of time depending on the type of stored vegetables B. After this cooling, the pressure in the cooling chamber is increased to return it to normal pressure, but when this pressure is increased, a pressure difference is created between the inside of the box A in a vacuum state and the outside due to a short-term sudden pressure increase action, resulting in the above-mentioned pressure difference. The closing sheet 5 made of an elastic material is sucked inward and is bent and deformed inward within the space of the ventilation hole 4, whereby the slit 6 in the closing sheet 5 becomes slightly open (the slit 6 is opened slightly). (Figure 5, chain line). Therefore, external air flows into the box from the slit 6 through the ventilation hole 4, so that the pressure difference between the inside and outside of the box does not increase any further, and the box does not bend excessively.
When the pressure returns to normal and the pressure difference between the inside and outside of the box disappears,
The closed sheet 5 returns to its normal closed state, and the vegetables inside can be kept cool. Example As sample products, a box made of a laminated material of one-sided corrugated cardboard and a foam sheet and having a valve mechanism using a slit-blocking sheet (products 1 to 3 of the present invention) and a corrugated cardboard box with holes (conventional product) were used. Filled with broccoli and heated at 7.5mmHg to 6mmHg for 30 minutes.
Vacuum precooling was carried out for 30 minutes. The temperature of the broccoli before and after vacuum precooling was measured, and the results shown in Table 1 below were obtained.

[Table] Valve: Sheet with slits According to the above results, products 1 to 3 of the present invention all have a temperature difference before and after pre-cooling that is almost the same as in the case of perforated cardboard boxes. Therefore, the suction and exhaust action during vacuum precooling is sufficiently performed, indicating that the valve mechanism using the slit-blocking sheet of the present invention can be applied to vacuum precooling. Example As a sample case, a box made of a laminated material of one-sided cardboard and a foamed sheet similar to the above example was used, and a box with a valve mechanism using a slit-blocking sheet (the product of the present invention) and a box with a valve mechanism that was not sensitive to the valve mechanism were used. Each box (comparison product) was filled with 10kg of green plums pre-cooled to 8℃, and ethylene absorbent was also stored and sealed. After leaving it at room temperature of 25℃ for 35 hours, the condition inside the box was examined. As a result, the results shown in Table 2 below were obtained.

[Table] As is clear from the above results, in the case of the present product equipped with a slit valve mechanism, carbon dioxide gas generated by respiration of vegetables (green plums) Because CO ₂ ) can escape to the outside, the concentration of carbon dioxide inside the box decreases.
The carbon dioxide gas disturbance is reduced compared to a box without a valve function. [Effects of the invention] As mentioned above, in the packaging box of the present invention, even when the lid is left closed during pre-cooling of vegetables by vacuum cooling, etc., the closing sheet that closes the ventilation hole provided in the inner flap at the top of the box can be used. By bending and deforming due to the pressure difference between the inside and outside of the body, the slit in it opens and can respond to the pressure reduction inside the box and the pressurization action to return it to normal pressure, preventing the box from bending and deforming. , precooling by vacuum cooling or the like with the lid closed can be carried out without any problems. In particular, the closing sheet that closes the ventilation hole of the inner flap is made thinner than the thickness of the outer flap so that it fits within the notch of the outer flap, so there is no excess protrusion on the outer surface of the box, and the appearance is improved. In addition to being good, even in a bypass where multiple boxes are directly stacked, it is possible to maintain a gap for the bending and deforming action of the closing sheet, and in combination with the fact that the notch opens on the side of the box body. This ensures ventilation during stacking and pre-cooling. Moreover, during normal times such as during transportation, the ventilation holes are kept closed by the elastic closing sheet, so there is no risk of outside air intrusion or cooling radiation, and the box body such as a cardboard box may have appropriate heat insulation properties. Therefore, the cold storage state due to pre-cooling can be maintained well, and the stored vegetables can be kept fresh for a long period of time, and they can be well protected without fear of dirt entering. Furthermore, since it is made of an assembled box such as a cardboard box, it can be folded flat and low in volume when not in use, increasing the efficiency of transporting and storing the empty box.

[Brief explanation of the drawing]

Fig. 1 is an enlarged perspective view of the main part showing one embodiment of the present invention, Fig. 2 is a cross-sectional view taken along the line from the front figure, Fig. 3 is a perspective view of the whole, and Fig. 4 shows the closure sheet facing outward. FIG. 5 is an enlarged sectional view of the main part in an elastically deformed state, FIG. 5 is a sectional view in a pre-cooled state, and FIG. 6 is a perspective view of a conventional cardboard box. A...Box body, 1...Side wall plate, 2a, 2b...Lower inner and outer flaps, 3a, 3b...Top inner and outer flaps, 4...Vent hole, 5...Closing sheet, 6...
...slit, 7...notch, B...vegetable.

Claims (1)

[Scope of utility model registration request] It is made of a foldable box body such as a cardboard box, and at the overlapping part of the inner and outer flaps connected to the upper end of the side wall plate, the inner flap is provided with a ventilation hole that communicates with the inside and outside, and a A closing sheet made of an elastic material and having a slit that can be opened by elastic deformation is attached to the outside so as to close the ventilation hole, and the corresponding outer flap has a space large enough to accommodate the closing sheet. A packaging box characterized in that it is provided with a notch that opens on the side of the box body.