JP3971436B2 - Lid easy separation type integrally formed container and method for manufacturing the same - Google Patents

Description

  The present invention relates to a container and a method for manufacturing the same, and more particularly to a lid easy-separation type integrally formed container in which a lid can be easily separated from a container body and a method for manufacturing the same.

  Conventionally, integrally molded containers have been widely used because of their ease of processing, low cost, light weight, and excellent transportability. In particular, those made of foamed resin are often used as food containers such as catered lunch boxes and take-out containers for reasons such as lightness, elasticity, heat retention, and ease of processing. Among such foods, the use as a natto container requiring appropriate air permeability is particularly excellent by using the lid without sealing.

  Natto is a selection process for selecting the raw soybean, a cleaning process for cleaning the selected soybean, an immersion process for immersing the cleaned soybean in water, a steaming process for steaming the soaked soybean, and steamed Inoculation process of inoculating natto bacteria into soybeans, filling process of filling soybeans inoculated with natto bacteria into natto containers, fermentation process of fermenting soybeans filled in containers to form natto, and ripening the formed natto It is manufactured and shipped through a ripening process, a packaging process in which accessories such as sauce and mustard are attached.

Since the container is used consistently from filling to consumption of soybean, functions required as a natto storage container are functions suitable for fermentation of soybean such as operability in the filling process, heat retention, moisture retention, and air permeability. In addition, functions such as hygiene and appropriate sales promotion are required.
Conventionally, as natto storage containers, baskets, warps, paper cups, trays made of expanded polystyrene resin, etc. have been used, but due to their advantages in function, cost, productivity, etc., the container body and lid have hinge parts. A natto container made of expanded polystyrene resin formed integrally therewith has become the mainstream.

  When you eat natto with this integrally formed natto container, it is common to open the lid, stir the natto, add seasonings such as sauce, mustard, etc. At this time, there was a problem that the lid part moved in the closing direction by the elasticity of the hinge part, which hindered stirring and eating. Therefore, in recent years, many natto containers that can easily separate the container body and the lid have been developed.

  As typical examples of lid-separated natto containers that have been developed so far, the natto container (Patent Documents 1 to 7) in which a perforation is provided in the hinge part of the integrally formed natto container, or a flange part near the hinge part A natto container (Patent Documents 8 to 10) provided with perforations.

  Although these natto containers with perforations are less difficult to separate the lid from the container body compared to monolithic natto containers without perforations, this perforation is generally used for container manufacture Because it is sometimes given, it is necessary to have a strength that can withstand various impacts during the manufacture of natto, and because of its strength, there is still a problem that cutting at the cutting part is not always easy. .

  Then, the natto container which formed the thin-walled cutting part which made the intensity | strength of a cutting part smaller was developed by heat-processing a hinge part after closing a lid | cover at the final stage of the manufacturing process of natto (patent document 11). However, in order to form the thin-walled cut portion, a high degree of precision is required for alignment between the container and the heater, and the positional relationship between the natto container and the heater is always kept constant, particularly when mass production is performed on a production line. Therefore, there is a problem that it is necessary to strictly adjust so that the production line is adjusted and monitored.

Japanese Patent Laid-Open No. 10-305886 JP-A-9-136353 Registered Utility Model No. 30493393 Japanese Utility Model Publication No. 4-118313 Japanese Utility Model Publication No. 61-59580 Japanese Utility Model Publication No. 58-194104 Japanese Utility Model Publication No. 53-81670 JP 2002-59990 A JP 2002-12283 A JP 2001-301735 A Japanese Patent No. 3619884

  Accordingly, an object of the present invention is to provide a lid easy-separation type integrally formed container that can solve the conventional problems and can be manufactured by a simpler method, and a method for manufacturing the same.

  In order to solve the above-mentioned problems, the inventors have intensively researched, surprisingly, with the lid body and the container body closed, an uneven shape in the thickness direction over the entire width of the hinge part. As a result of further research, the inventors have found that the above problems can be solved by forming a thin-walled cut portion by heat processing.

That is, the present invention includes a container body and a lid body integrated with the container body via a hinge portion, and the lid body by cutting the thin cut portion provided in the hinge portion after the lid body is opened. A natto container that can be separated from the container main body, wherein the thin-walled cutting portion has a thickness over the entire width of the hinge portion by contacting the gear-type heater with the lid body and the container main body closed. The present invention relates to the natto container, which is heat-processed in a concavo-convex shape in the vertical direction and cured by heat denaturation .
The present invention also relates to the natto container according to claim 1, wherein the thin-walled cut portion has at least one through hole.
Furthermore, this invention relates to the said natto container in which a thin-walled cutting part has a through-hole of a fixed space | interval.
The present invention also relates to the natto container, which is made of expanded polystyrene.
Furthermore, this invention relates to the said natto container whose tensile force of a thin-walled cutting part is 50 g or more and 800 g or less.

The present invention also includes a container main body and a lid integrated with the container main body via a hinge portion, and the lid and the container are cut by cutting a thin cut portion provided in the hinge portion after the lid is opened. A method of manufacturing a natto container that can be separated from a main body,
A step of integrally molding the container body and the lid through the hinge portion;
A step of closing the lid and the container body,
A step of heat-processing in a concavo-convex shape in the thickness direction over the entire width of the hinge portion of the closed container by contacting the gear-type heater ;
The method.
Furthermore, this invention relates to the said method including the process of filling a container main body with natto before the process of closing a cover body.

  In the container of the present invention, not only can the lid and the container body be easily separated by adopting the above-mentioned configuration, but the distance between the container and the heater needs to be set accurately when the container is manufactured. Since it can be set roughly to some extent, it is very effective in terms of manufacturing cost.

  In addition, since the hinge part is melted by heat processing, the thin-walled cut part loses stretch orientation (raw fabric orientation) in the melted part, and when the entire container is made of foamed synthetic resin Since the foam becomes a solid body, the physical boundary between the thin-walled cut portion and the other portions is clearly formed, and a thin-cut portion with good sharpness can be realized.

  As mentioned above, although the effect of the present invention was explained centering on the natto container, it is applicable not only to the natto container but also to a container for any contents as long as the user can use the lid appropriately separated. It goes without saying that the same effect can be achieved.

Although the manufacturing process of the container of this invention is shown below, this invention is not limited to this at all.
Steps 1 to 10 shown in FIGS. 1 and 2 are the same as the manufacturing steps of a normal natto container.
Process 1: The process which heats the synthetic resin sheet 1 used as a raw material with the heating apparatus 2 (FIG. 1A)
Step 2: Vacuum forming the heated sheet 1 with the mold 3 (FIG. 1B)
Step 3: A step of cutting the lid-container integrated molding 10 from the vacuum-formed sheet 1 into individual containers with the cutter 4 (FIG. 1C)
Process 4: The process of stacking the cut and formed integrally molded product 10 (FIG. 1D)
Step 5: Using the container feeder 5, a step of placing the stacked integrally molded products 10 on the conveyor 6 one by one as containers 11 (FIG. 2A).
Process 6: The process of filling the container on the conveyor 6 with the steamed soybean 8 seeded with Bacillus natto using the boiled bean filling machine 7 (FIG. 2B).
Process 7: The process which covers the film 12 cut | disconnected to the appropriate magnitude | size on the steamed soybean 8 with which the container was filled using the film pushing cutter 9 (FIG. 2C)
Process 8: The process of throwing the seasoning bag 13 containing a sauce, mustard, etc. on the film 12 using the seasoning bag thrower 14 (FIG. 2D)
Step 9: Step of folding the hinge portion 22 so that the container body 20 and the lid body 21 of the container overlap and closing the lid (FIGS. 2E and 3A to 3C)
Process 10: The process of joining the flange part 23 of the opposite side of the bent hinge part 22 with the lid sealing machine 15 (FIG. 2E).

  In addition, the said process summarized the outline of the manufacturing process of a general product, Comprising: The order of a process can be changed arbitrarily, can be omitted arbitrarily, and another process can be added. For example, even a process that is essential for producing a natto product, such as a natto fermentation process, may be omitted as appropriate.

  The container of this invention can be manufactured by processing the hinge part 22 after the said process 9 or 10 (after closing a lid | cover). Next, as a means for keeping the lid 21 and the container main body 20 closed, the lid and the container main body may be fitted, and a part of the lid and the container main body (preferably both May be joined by welding, bonding, or the like.

  The container of the present invention, for example, as shown in FIG. 4, when two thin-walled portions 25 are formed on the hinge portion 22, from the outside of the thin-walled portion formed by bending the hinge portion (hereinafter referred to as a processed portion), A thin-walled cut portion is formed by processing the concave and convex portions in the thickness direction over the entire width of the hinge portion (step 11). This processing can typically be performed by thermal processing in which heating is performed directly or indirectly using a heater or the like. In addition to thermal processing, it can also be performed by cutting the processed portion using a cutter or the like. From the viewpoints of operability, simplicity, cost, etc., thermal processing is preferable, and in particular, thermal processing by directly contacting a heater is preferable (FIG. 5).

In order to process the projections and depressions, it can be performed by rotating a gear-type heater 24 against the hinge as shown in FIGS. 4 and 5, but is not limited thereto. Typically, as shown in FIGS. 6A and 6B, the gear 32 moves in the direction of the rotation direction b as the container 11 moves in the direction of the arrow a on the conveyor without providing the drive unit in the gear heater 24. It is sufficient to keep it rotating. Further, the method for heating the gear portion of the gear-type heater 24 is not particularly limited. For example, there is a heat source 31 outside the gear 32 and the gear 32 is heated from the heat source 31 from the outside (FIG. 6A), A method of heating from the center of the gear 32 (FIG. 6B) and the like include the heat source 31 at the center of the gear 32.
In addition, as another method for processing the uneven shape, for example, the hinge portion can be formed in an uneven shape by vibrating or swinging a normal heater against the hinge portion. It can also be formed by hitting the hinge part.
When the gear type heater 24 is used, by appropriately adjusting the shape of the gear, and when a normal heater is vibrated or oscillating or when a comb type heater is used, by appropriately adjusting the operating range of the heater, It is possible to set the distance between the container and the heater relatively roughly.

In the present invention, processing to be uneven in the thickness direction means that the thickness is constant in the thickness direction of the thin-walled cut portion 26 in the cross-section XX ′ of the thin-walled cut portion 26 as shown in FIGS. In other words, processing is performed so that a thick part (d ₁ : convex part) and a thin part (d ₂ : concave part) are formed. You may process so that a convex part and a recessed part may be formed regularly regularly. Here, when d ₂ is 0, the through hole 33 is formed. The through holes 33 may be formed in the thin cut portion 26 at regular intervals.

Moreover, in the hinge part which has two thin parts, among the two thin parts on the cover body side and the container main body side, the heat melting part may be on the cover body side or on the container main body side, Because of the ease of installation of the heater, the processed part on the lid side is usually processed to form a thin cut part.
In the formation of thin-walled cut parts by heat processing, the material of the container is cured by heat denaturation, and the lid body and the container main body are cut along the cured part, so that no part other than the cut part is damaged. . In particular, when the material of the container is a foamed resin, only the heated part is more effective because the foam in the foam disappears due to thermal melting and becomes a solid body that is thinly cured. That is, regardless of the original fabric orientation, it is possible to form a thin cut portion that is excellent in a crisp feeling and can be easily cut.

The material of the container of the present invention is not limited as long as the container body and the lid can be formed so as to be integrated with each other through the hinge part and can be processed in the folded hinge part, but a synthetic resin is preferable, and particularly lightweight. A foamable synthetic resin having excellent properties and processability, such as foamed polystyrene and foamed polyolefin, is preferably used.
Manufacturing a large quantity of containers according to the present invention involves fixing the gear-type heater 24 on the production line and positioning the containers on the conveyor so that the processed portion of the container contacts the gear-type heater 24 with an appropriate pressure. By moving the conveyor, a plurality of containers can be successively and sequentially brought into contact with the gear heater 24 so as to be thermally processed. In the present invention, positioning in this case can be performed relatively roughly.

In this way, when the container is placed on the conveyor and moved and brought into contact with the fixed gear-type heater 24, the heat of the gear-type heater 24 needs to be appropriately transmitted to the processing portion of the container, and the heat is transmitted too much. Then, the thin-walled portion is completely cut, and if the heat is transmitted only insufficiently, the thin-walled cut portion has a strength that cannot be easily cut.
The heating conditions can be changed as appropriate according to the size, thickness, material, etc. of the container, and it is appropriate to increase the contact time when the heater temperature is low and shorten it when the temperature is high. Heat processing can be performed. From such a viewpoint, the temperature of the heater is typically 120 to 800 ° C. Further, the contact angle of the heater is not particularly limited as long as the heater comes into contact with the processed portion, but typically, the contact angle is 20 to 70 degrees, preferably 45 degrees from the horizontal. By appropriately adjusting these heating conditions, it is possible to form a thin cut portion having a desired arbitrary thickness.

  In the container of the present invention, the thickness of the thin-walled cutting portion is such that the container body and the lid can be easily separated from each other, and the state where the lid is locked to the container body can be maintained. The thickness is not particularly limited, but when the container is used for natto, the thickest uneven portion is preferably 0.8 mm or less, particularly preferably 0, for ease of separation between the container body and the lid. .6 mm or less, and more preferably 0.3 mm or less. The thinnest uneven portion may be about 0.05 mm, but may be a through hole. Moreover, when the container is for natto, the tensile force of the thin-walled cut portion is 800 g or less, preferably 50 to 800 g, and particularly preferably 150 to 500 g.

(Example)
In order to confirm the easy separation of the containers of the present invention, the tensile force at the hinge part was measured and compared for each of the following containers 1 to 3.

Container 1: Container of the present invention (for natto)
Material of container: Polystyrene foam Length of container hinge: 100 mm
Container thickness: about 2mm
Thin-walled part: 2 strips on the hinge part (of which the lid side is heat-processed), about 1 mm thick
Heater shape: Gear type (diameter: 11 mm, pitch: 1.7 mm)
Heater temperature: 400 ° C
Heater contact time: 0.5 seconds for a length of 100 mm Heater contact angle: 45 degrees from the horizontal Thin cut part: Hinge part lid side, uneven (thickest part: about 0.7 mm, thinnest part: penetration Is a hole)

Container 2: Natto container with perforation (perforation is mechanically formed)
Material of container: Polystyrene foam Length of container hinge: 100 mm
Container thickness: about 2mm
Thin-walled part: 2 strips on the hinge, about 1 mm thick
Perforation: Thin part on the container body side, hole length: 4 mm, interval: 1 mm

Container 3: Natto container with no cutting part Container material: Expanded polystyrene Length of hinge part of container: 100 mm
Container thickness: about 2mm
Thin-walled part: 2 strips on the hinge, about 1 mm thick

The tensile force at the hinge part of each natto container (containers 1 to 3) is such that the container body side is fixed, the hinge part is parallel to the ground, and the lid body is vertically above the container body. A spring alone (measurement range of 2 kg or less) was attached to the upper end of the body, and the force when the container body and the lid body were separated was measured. The measurement was performed 10 times or more. The results are shown in Table 1.

As shown in Table 1, the container 1 did not require a force exceeding 800 g for separation, and was well separated with a light force of about 500 g or less (about 250 to 500 g). Container 2 required an average force of about 610 g. Further, the container 3 cannot separate the lid and the container main body by the above-described method, and the tensile force cannot be measured.
When the lid body and the container body were separated from each other in a state in which the containers 1 and 2 were close to the actual use state, the following differences were observed.
In the container 1, since the heat-processed part is in a solidified state, the restoring force of the hinge part in the opening direction of the lid body is reduced, and when the lid is opened, the solidified part sounds crisp and excellent in feeling of use. ing. In addition, when the lid was opened and the flange portion of the container main body and the flange portion of the lid at both ends were gripped and pulled, it was separated well so that it could be cracked. What was cut | disconnected in parts other than a thin-wall cutting part was not seen.
If the container 2 was separated sufficiently carefully, there was no separation at locations other than the perforations. However, when it was quickly separated, damage was observed in the hinge portion and the container body other than the perforations. Further, when the flanges at both ends were gripped and separated while the lid was opened, the hinge part was broken and good separation could not be performed.
Even when the container 3 is separated sufficiently carefully, a portion other than the cut portion may be cracked or the container body may be damaged.

It is a flowchart which shows the manufacturing process of the container of this invention. A to D schematically show steps 1 to 4, respectively. The lower row is a top view of the container. It is a flowchart which shows the manufacturing process of the container of this invention. A to D schematically show steps 5 to 8, respectively, and E schematically shows a series of steps 9 to 10. The lower row is a top view of the container. It is a flowchart which shows the manufacturing process of the container of this invention. A to C schematically show a series of steps 9. It is the schematic which shows the one aspect | mode of the manufacturing process of the container of this invention. A schematically shows the formation of the thin-walled cut portion by the contact of the heater. B schematically shows the formed thin cut portion. It is the schematic which shows the one aspect | mode of the manufacturing process of the container of this invention. A is a side view showing formation of a thin-walled cut portion by contact of a heater. B is a top view showing formation of a thin-walled cut portion by contact of a heater. It is the schematic which shows the one aspect | mode of the gear type heater which can be used for this invention. A is a conceptual diagram showing a method of heating a gear from a heat source outside the gear. B is a conceptual diagram showing a method of heating a gear from a heat source at the center of the gear. It is explanatory drawing which shows the thin cut part processed into the uneven | corrugated shape of this invention. A is a schematic diagram showing an appearance when there is a through hole. B and C are cross-sectional views of the thin-walled cut portion, where B is an explanatory view showing a case where there is no through hole and C is a case where there is a through hole.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Synthetic resin sheet 2 Heating device 3 Mold 4 Cutter 5 Container supply machine 6 Conveyor 7 Boiled bean filling machine 8 Steamed soybean 9 Coated push cutter 10 Integral molding 11 Container 12 Coating 13 Seasoning bag introduction machine 15 Cover seal Machine 20 Container body 21 Lid 22 Hinge part 23 Flange part 24 Gear heater 25 Thin part 26 Thin part cut part 31 Heat source 32 Gear 33 Through hole

Claims (7)

A container body and a lid body integrated with the container body via a hinge portion are provided, and the lid body and the container body are separated by cutting a thin cut portion provided in the hinge portion after the lid body is opened. A natto container that is capable of forming a concavo-convex shape in the thickness direction over the entire width of the hinge portion by contacting the gear-type heater with the thin-walled cutting portion in a state where the lid body and the container body are closed. The natto container, which is heat-processed and cured by heat denaturation .   The natto container according to claim 1, wherein the thin cut portion has at least one through hole.   The natto container according to claim 2, wherein the thin-walled cut portion has through-holes at regular intervals.   The natto container according to any one of claims 1 to 3, which is made of expanded polystyrene.   The natto container in any one of Claims 1-4 whose tensile force of a thin-wall cutting part is 50 g or more and 800 g or less. A container body and a lid body integrated with the container body via a hinge portion are provided, and the lid body and the container body are separated by cutting a thin cut portion provided in the hinge portion after the lid body is opened. A method for manufacturing a natto container,
A step of integrally molding the container body and the lid through the hinge portion;
A step of closing the lid and the container body,
A step of heat-processing in a concavo-convex shape in the thickness direction over the entire width of the hinge portion of the closed container by contacting the gear-type heater;
Including said method.   The method of Claim 6 including the process of filling a container main body with natto before the process of closing a cover body.

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