JP4396807B2 - Gas replacement packaging equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas replacement packaging in which a container such as a cup or a tray in which contents are put is subjected to gas replacement with an inert gas and sealed. Dress Related to the position.
[0002]
[Prior art]
Conventionally, in order to be able to preserve a package obtained by filling and sealing containers such as cooked rice, prepared dishes, and beverages at room temperature for a long time, the amount of oxygen left inside the package It is necessary to reduce the quality of food and beverages as much as possible. Therefore, gas replacement packaging is used in which a gas such as air remaining in the head space in the container filled with contents is replaced with an inert gas such as nitrogen.
[0003]
As one of the gas replacement packaging, steam is blown into the semi-rigid container body filled with the contents near room temperature, leaving the space part, and only the vicinity of the surface of the contents is heated, and then the inert gas is blown into the space. Replace the water vapor and residual air in the section with inert gas, and then immediately seal the container body with the lid, or heat only the surface of the contents by blowing a mixture of water vapor and inert gas. A method of manufacturing a sealed container is proposed in which residual air in the space is replaced with an air-fuel mixture, and then the container body is immediately sealed with a lid (Patent Document 1).
[0004]
According to this method for manufacturing a sealed container, the space in the container is replaced with the inert gas or a mixture of water vapor and inert gas, so that the amount of oxygen remaining in the space can be made very small. Moreover, the water vapor | steam which heated only the surface of the content loses latent heat, condenses, and adheres to the surface of the content as a water droplet. Condensed water evaporates even during a short period of time after the inert gas is blown, and becomes water vapor, and after the container is sealed, the water vapor condenses during cooling to room temperature, and the inside of the container becomes negative pressure. To do. At this time, in the sealed container, the relatively bendable portions such as the bottom wall and the lid are usually slightly bent to a position where the internal volume is reduced and the internal and external pressure balance is balanced. By making the amount of water vapor in the space portion relatively small, it is intended not to cause large shrinkage deformation so as to lose commercial value.
[0005]
As described above, in the filling / sealing device, steam is blown before gas replacement, and after sealing and cooling, the steam condenses into water droplets or the like, thereby lowering the pressure inside the container, and the cover material is removed by the external pressure. It is done to dent inside. The fact that the container is not expanded due to the deterioration of the quality due to the depression of the lid material has been made to improve the appearance. Moreover, when the content is cooked rice, the surface of the rice is sterilized by steam, and fungi such as fungi are difficult to propagate. Furthermore, the heat seal can be further stabilized by warming the container by spraying steam before heat sealing.
[0006]
However, when the contents are cooked rice, it is necessary to spray a large amount of steam. In such a case, after the container sprayed with steam is sealed with a lid or the like, the steam occupying the head space When the water is condensed and a large decompression occurs, there is a disadvantage that the container is greatly distorted and the appearance of the container is impaired. In addition, since a large amount of steam is used at a manufacturing site where such a container package is manufactured in large quantities, it is difficult to completely prevent the steam from leaking into the factory, so the inside of the factory becomes hot and humid. This makes it easier for bacteria to propagate. If an inspection machine is installed, the hot and humid environment may cause the computer equipment to malfunction. Therefore, it has been considered that it is actually difficult to apply the spray of steam to the container containing the contents to an actual container packaging. Furthermore, if a situation occurs in which outside air is drawn into the container before the container is sealed due to the decompression of the inside of the container due to condensation of steam, the inside of the container may be contaminated by fungi. However, this outside air is drawn into the container. There is also a problem that it is difficult to completely prevent the phenomenon.
[0007]
[Patent Document 1]
Japanese Unexamined Patent Publication No. 63-178918 (pages 3-4, figure)
[0008]
[Problems to be solved by the invention]
In gas replacement packaging, it is obtained by spraying steam such as depressurization inside the container by condensation of water vapor after the cooling, sterilization of the surface of the contents such as cooked rice, and preheating for good heat sealing as described above. It is difficult to throw away the benefits. Therefore, in addition to preventing leakage of the sprayed steam to the surrounding environment, by replacing a part of the steam in the container with an inert gas again, the problem caused by the spraying of steam is reduced or eliminated. There are issues to be solved.
[0009]
An object of the present invention is to provide a gas replacement packaging method and apparatus capable of avoiding high-temperature and high-humidity in a factory due to the use of steam while ensuring the advantage of spraying steam. It is.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the gas replacement packaging method according to the present invention includes a container in which a container having contents has a cross-sectional shape substantially similar to a cross-sectional shape exhibited by the container and a cradle that supports the container. During the transfer, the spraying of steam into the container and the subsequent gas replacement with an inert gas are performed, and the container is sealed after passing through the chamber.
[0011]
According to this gas replacement packaging method, when a container containing contents is transported in the chamber, first, steam is blown into the container, whereby the gas in the container is replaced by steam, and the surface of the contents is made by steam. Sterilized. When the container sprayed with steam is further transported in the chamber, gas replacement with an inert gas is performed. Steam is sprayed in a chamber having a cross-sectional shape substantially similar to the cross-sectional shape of the container and the cradle that supports the container, so that steam leakage from the chamber can be easily managed, and the inside of the factory is hot and humid. Can be prevented. Even if the gas leaks from the outlet of the chamber, the gas becomes an inert gas, so that the surrounding environment that occurs when the steam leaks does not become hot and humid. The steam is cooled from the outlet of the chamber to the completion of the sealing of the container, resulting in partial condensation, and the phenomenon that the inside of the container is decompressed and draws in external air is likely to occur. It is possible to substantially eliminate such an outside air pull-in phenomenon by performing gas replacement of the part with an inert gas. Even if steam remaining in a small amount in the container is condensed, excessive decompression does not occur in the sealed container, and the appearance of the sealed container can be maintained. Further, when the container is sealed by heat sealing of a packaging material such as a lid, the portion where heat sealing is planned is preheated by steam, and a good heat seal can be obtained.
[0012]
In this gas replacement packaging method, pre-gas replacement can be performed by spraying the inert gas into the container before spraying the steam while the container is transporting through the chamber. By performing the pre-gas replacement by blowing an inert gas, the outside air containing oxygen can be removed in advance, and the gas replacement efficiency can be improved. Further, in the chamber, since the replacement gas is injected before and after the steam is blown, it is possible to prevent the steam from leaking in the front-rear direction of the container conveyance direction. Furthermore, since the container containing the contents is sprayed with the inert gas over the two areas before and after traveling in the chamber, the contents in the container are exposed to the inert gas for a long time as a whole. In particular, more oxygen remaining in the contents such as cooked rice can be expelled, and the removal rate of dissolved oxygen can be increased.
[0013]
In this gas replacement packaging method, it is preferable that air is exhausted from a position below the transport path of the container in a steam region where the steam of the chamber is sprayed. Since a large amount of steam and a highly sealed chamber are used, it is preferable to set the exhaust amount so that the inside of the chamber is slightly pressurized with respect to the surrounding environment. The utility value of steam is higher in the high temperature state immediately after injection. By performing evacuation at the lower side of the chamber, it is possible to discharge the steam having low utility value existing below from the chamber. Further, since the exhaust port may become dirty, it is preferable that the chamber is exhausted at a lower position which is a safe side for hygiene purposes.
[0014]
Further, the gas replacement packaging apparatus according to the present invention has a cross-sectional shape substantially similar to the cross-sectional shape exhibited by the container containing the contents and the cradle that supports the container, and the container is supported by the cradle. A chamber that is transported inside by the transport means, steam spraying means that sprays steam onto the container that is disposed in the chamber and is passing through the chamber, and is disposed downstream of the steam spraying means in the chamber. It comprises an inert gas spraying means for spraying an inert gas on the container passing through the inside, and a sealing means disposed next to the outlet of the chamber for sealing the container.
[0015]
According to this gas replacement packaging apparatus, the container containing the contents is transported by the transport means while being supported by the cradle, and has a cross-sectional shape substantially similar to the cross-sectional shape exhibited by the container and the cradle that supports the container. When the steam injection means disposed in the chamber sprays steam on the container, the inside of the container is filled with steam, the outside air is expelled, and the contents are discharged. The surface is sterilized by steam. When the container filled with steam is further transported through the chamber, the inert gas spraying means disposed downstream of the steam spraying means sprays the inert gas on the container. Part is replaced with inert gas. The injected steam is prevented from flowing to the outlet side of the chamber where the opening for carrying out the container is formed by the inert gas ejected from the inert gas ejecting means, and the steam leaks to the external environment through the outlet. Can be prevented. Even if a gas leaks from the outlet of the chamber, the gas becomes an inert gas, so that the surrounding environment that occurs when steam leaks does not become hot and humid. In addition, the container leaving the chamber is sealed by a sealing means disposed following the outlet of the chamber, but even if the steam is cooled within a short period until the sealing is completed, the amount of steam in the container is reduced. Therefore, it is possible to substantially prevent the outside air from being drawn into the container due to excessive decompression.
[0016]
In the gas replacement packaging apparatus, the chamber passes through a boundary portion between a steam region where the steam is sprayed by the steam injection unit and a gas replacement region where the inert gas is sprayed by the inert gas injection unit. It can be set as the labyrinth part which narrowed the clearance gap left between containers. In order to more efficiently prevent the sprayed steam from leaking into the surrounding environment, it is preferable to suppress the steam from flowing to the outlet side of the chamber as much as possible. Therefore, in the chamber, by making the boundary portion between the steam region and the gas replacement region a labyrinth portion with a narrow gap left between the passing container, the passage resistance when steam tries to pass the labyrinth portion And the steam can be efficiently prevented from flowing into the gas replacement region.
[0017]
In this gas replacement packaging apparatus, pre-inert gas injection means for spraying the inert gas to the container passing through the chamber upstream of the steam injection means can be disposed in the chamber. Depending on the contents to be packaged, it is required to reduce the amount of dissolved oxygen as much as possible in order to prevent alteration. In order to reduce the amount of dissolved oxygen in the contents, it is effective to increase the temperature and to increase the exposure time to the replacement gas. Further, it is preferable to prevent the steam injected into the chamber from leaking out even at the inlet side of the chamber. Therefore, by providing pre-inert gas injection means for spraying inert gas to a container passing through the chamber upstream of the steam injection means, sufficient time for the contents to be exposed to the inert gas is secured. In addition, it is possible to prevent the steam sprayed from the steam spraying means from going up in the chamber to the upstream side of the conveyance and leaking from the inlet side of the chamber to the surrounding environment.
[0018]
In the gas replacement packaging apparatus provided with pre-inert gas injection means, in the chamber, a steam area where the steam is sprayed by the steam injection means, and a pre-gas replacement area where the inert gas is sprayed by the pre-inert gas injection means Can be a pre-labyrinth portion with a narrow gap left between the container and the container passing therethrough. In order to more efficiently prevent the sprayed steam from leaking into the surrounding environment, it is preferable to suppress the steam from flowing to the inlet side of the chamber as much as possible. Therefore, in the chamber, when the boundary portion between the steam region and the pregas replacement region is a pre-labyrinth portion with a narrow gap left between the passing container, the steam is about to pass through the pre-labyrinth portion. The passage resistance is increased, and it is possible to efficiently prevent the steam from flowing into the pregas replacement region.
[0019]
In the gas replacement packaging apparatus, an exhaust port connected to the exhaust unit can be formed in the chamber below the transport path of the container in a steam region where the steam is sprayed by the steam injection unit. Since the steam is continuously sprayed by the steam spraying means, the sprayed steam must be finally discharged from the chamber even if a part of the steam is condensed. Therefore, by forming an exhaust port connected to the exhaust means at a position below the container conveyance path in the region where steam is sprayed, the steam is discharged from the chamber without going to the gas replacement region or the pre-gas replacement region. Can be guided. Moreover, it is preferable to discharge the steam remaining below the container because the temperature is lowered and the steam cannot be used for surface sterilization of the contents. In addition, it is preferable to collect | recover, without discharging | emitting steam to surrounding environment by connecting an exhaust means to a duct etc. The chamber is preferably maintained at a temperature of 100 ° C. or higher in order to prevent steam condensation.
[0020]
In the gas replacement packaging apparatus including the exhaust unit, the exhaust unit is a natural exhaust unit that performs natural exhaust from the exhaust port or a forced exhaust unit that performs forced suction exhaust through the exhaust port. It is preferable that the pressurized state is slightly higher than the surrounding environment. The exhaust unit can be configured as a natural exhaust unit or a forced exhaust unit according to, for example, the amount of steam sprayed. In the case of natural exhaust as well as in forced exhaust, it is preferable that the pressure in the chamber be slightly higher than the surroundings in order to avoid drawing outside air into the chamber. Further, the exhaust port is preferably kept at a temperature of 100 ° C. or higher in order to prevent condensation of steam.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the gas replacement packaging method and apparatus according to the present invention will be described with reference to the accompanying drawings. 1 is a schematic side view of a main part of a gas replacement packaging apparatus according to the present invention, FIG. 2 is a cross-sectional view taken along line AA of the gas replacement packaging apparatus shown in FIG. 1, and FIG. FIG. 4 is a cross-sectional view, and FIG. 4 is a perspective view of a chamber disposed in a chamber station of the gas replacement packaging apparatus.
[0022]
A gas replacement packaging apparatus 1 shown in FIG. 1 is applied to an aseptic filling and sealing process, and is made of a synthetic resin tray-like container 6 (only a part is given a symbol. , Simply referred to as “container 6”) with rice 7 (see FIG. 2) and the inside of the container 6 containing cooked rice 7 replaced with an inert gas such as nitrogen gas. It is an apparatus for sealing the container 6 containing cooked rice by heat-sealing the lid 8 made of a synthetic resin film that has been treated. The gas replacement packaging apparatus 1 includes, as viewed in the conveying direction, a sterile space station 2, a chamber station 3 for spraying steam and an inert nitrogen gas as a replacement gas, a container 6 containing cooked rice 7 and a lid 8. A sealing station 4 for heat-sealing, and a package take-out station 5 for taking out a package 9 of cooked rice 7 sealed with a lid 8.
[0023]
The aseptic space station 2 is a closed space provided with a transfer part 2a of the container 6 and a content filling part 2b that is located on the downstream side of the container 6 and fills the rice 7 that is the contents. Aseptic air is supplied to the inside of the sterile space station 2 from a sterile air supply source (not shown), and the container 6 is aseptically dried. In the transfer section 2a, the container 6 is supplied to a receiving base 16 described later by a container supply mechanism (not shown). The container 6 placed on the cradle 16 is filled with cooked rice 7 as the contents in the content filling part 2b. An air curtain 2d for blowing down sterile air is provided at the outlet 2c of the sterile space station 2 to prevent mixing of the sterile air in the sterile space station 2 and the gas in the subsequent chamber station 3.
[0024]
The chamber station 3 is a station that sprays steam and nitrogen gas as an inert gas onto the container 6 containing the cooked rice 7, and is provided with a pregas replacement region 3a, a steam region 3b, and a gas replacement region 3c in order from the upstream side. It has been. In FIG. 1, the chamber station 3 is drawn in a compact manner, but in each part of the pre-gas replacement region 3a, the steam region 3b, and the gas replacement region 3c, the transport section that is transported by being exposed to gas is set to a considerable length. . In the chamber station 3, a chamber 10 to be described later is disposed, and the container 6 supported by the receiving table 16 is conveyed inside the chamber 10. In the pre-gas replacement region 3a and the gas replacement region 3c, inert gas injection means 26 and 28 each including a nozzle for injecting an inert gas are provided on the upper portion of the chamber 10, and in the steam region 3b, the chamber 10 A steam spraying means 27 comprising a nozzle for spraying steam is provided on the top of the head. Although not shown, the chamber 10 is provided with a heater for heating the chamber 10 to 100 ° C. or higher.
[0025]
Of the chamber 10, the vicinity of the inlet of the pregas replacement region 3a, the connection between the pregas replacement region 3a and the steam region 3b, the connection between the steam region 3b and the gas replacement region 3c, and the vicinity of the outlet of the gas replacement region 3c. Are made into labyrinth parts 10a, 10b, 10c and 10d, respectively, by narrowing the gap formed between the container 6 and the container 6 being conveyed. As for the space in the chamber 10 above the container 6 containing the cooked rice 7, the partition 10e is used at the boundary between the pregas replacement region 3a and the steam region 3b, and the partition 10f is used at the boundary between the steam region 3b and the gas replacement region 3c. Can be partitioned. In the steam region 3b, the exhaust means 11 is provided below the conveyance path through which the container 6 is conveyed. As shown in FIG. 2, the exhaust means 11 includes a duct 36 connected to an exhaust port 35 that opens to the chamber 10, a blower 37 that is provided in the duct 36 and sucks and exhausts the gas in the chamber 10, and upstream of the blower 37. And a damper 38 for adjusting the exhaust amount. The exhaust flow exhausted from the blower 37 is collected so as not to leak into the surrounding environment.
[0026]
It is sufficient that the sealing station 4 has a known structure. The sealing station 4 heat seals the lid material roll 12 on which the lid material 8 is wound up and the lid material 8 fed out from the lid material roll 12 to the container 6 containing the cooked rice 7 and the lid material 8 for each container 6. The lid material seal cut portion 13 for cutting the lid material 8 and the surplus lid material winding portion 14 for winding the lid material surplus portion 8a generated by cutting the lid material 8 are provided. The sealing station 4 is supplied with aseptic air to maintain sterility, and the lid 8 is sterilized by a UV lamp (not shown) before heat sealing. The lid material seal cut portion 13 includes an upper mold heat block 13a and a lower mold heat block 13b that operate in synchronization with each other, and heat-seal the container 6 and the lid material 8 by sandwiching them and heating them. In the illustrated example, the lid 8 can be heat-sealed and the lid 8 can be cut simultaneously with respect to the four containers 6. A package 9 of cooked rice 7 is manufactured by heat-sealing the lid 8 to the container 6 in a state where the container 6 is covered with the lid 8. The sealed package 9 of cooked rice 7 can be taken out from the production line at the package take-out station 5.
[0027]
Each of the aseptic space station 2, the chamber station 3, the sealing station 4, and the package take-out station 5 is sequentially arranged along the transport path of the upper traveling portion 15d of the magnetic conveyor 15 as a transport device. . The magnetic conveyor 15 includes a drive sprocket 15a, a driven sprocket 15b, and a chain 15c (see FIGS. 2 and 3) wound around the drive sprocket 15a and the driven sprocket 15b. As will be described later, a magnet provided in the chain 15c. Acts magnetically on the cradle 16 to transport the container 6. Water droplets that may adhere to the cradle 16 due to condensation of steam sprayed at the chamber station 3 are received by a water droplet receiver 17 disposed around the drive sprocket 15a. The cradle 10 is subsequently cleaned in the cleaning station 18 while being transported through the lower traveling unit 15e, and the cradle 16 that has exited the cleaning station 18 is blown into the side near the driven sprocket 15b. It is dried while traveling in the drying chamber 19 provided with an exhaust port 19b on the side close to the drive sprocket 15a, and is carried into the aseptic space station 2 at a position returning to the upper traveling unit 15d.
[0028]
In the chamber station 3, a chamber 10 shown in a perspective view in FIG. The chamber 10 has a flat top plate 20 and a bottom portion 22 having a space that is enlarged with respect to the top plate 20 in a central region, and a shelf portion whose left and right sides are connected to a high position with respect to the bottom portion 22 through standing portions 22a and 22a. 23 and 23, and the lower side wall plates 24 and 24 connected at the left and right ends of the upper plate 20 and the lower plate 21 are formed. An inlet opening 25a into which the container 6 containing the cooked rice 7 in a state supported by the cradle 16 is carried and an outlet opening 25b to be carried out are formed before and after the conveying device. Therefore, the chamber 10 is surrounded by the upper plate 20, the lower plate 21, and the side wall plates 24, 24 around the conveyance path, and is closed and elongated as a whole except for the exhaust means 11, the inlet opening 25a, and the outlet opening 25b. The chamber. As apparent from FIGS. 2 to 4, the cross-sectional shape of the chamber 10 is similar to the cross-sectional shape of the container 6 and the cradle 16 that supports the container 6 and is formed slightly larger.
[0029]
The arrangement of the container 6 in the chamber 10 is shown in FIGS. As shown in FIGS. 2 and 3, the cradle 16 is formed in a rectangular frame shape as a whole into which the main body 6 a of the container 6 enters the center, and can pass through the chamber 10. The cradle 16 includes a magnet 30 and a sliding material 31. The container 6 is supported on the cradle 16 by placing a flange 6b formed around the opening on the cradle 16, and is conveyed by the magnetic conveyor 15 in this state. That is, in the magnetic conveyor 15, a pair of chains 15c and 15c are wound around the drive sprocket 15a and the driven sprocket 15b on the left and right in the transport direction, and the magnets 32 and 32 provided on the chains 15c and 15c are provided on the cradle 16. The container 6 is transported by acting magnetically with the magnet 30. Each chain 15c is attached to the apparatus frame 33 so as not to loosen during traveling, and is guided to a guide rail 34 disposed in parallel with the shelf 23 formed on the lower plate 22 of the chamber 10. To be run. With this structure, the magnets 32 and 32 can travel close to the lower side surfaces of the shelf portions 23 and 23 formed on the lower plate 22 of the chamber 10. The sliding materials 31 and 31 are formed of a low friction material so that the cradle 16 is smoothly slid and conveyed on the shelves 23 and 23.
[0030]
As shown in FIG. 3, in the labyrinth portion 10 c, a portion that rises from the bottom portion 22 of the chamber 10 and connects to the shelf portion 23 is formed into a copying portion 40 that is curved following the shape of the main body portion 6 a of the container 6. Therefore, in the region where the labyrinth portion is not formed as shown in FIG. 2, the labyrinth portion 10 c is compared with the bottom portion 22 and the large gap 42 formed between the perpendicular standing portion 22 a and the main body portion 6 a of the container 6. The gap 41 formed between the copying portion 40 and the main body 6a of the container 6 is very narrow, and has a structure in which a gas such as steam or nitrogen gas is difficult to pass due to a large flow path resistance. The gas injected into the chamber 10, in particular steam, is difficult to flow to the pre-gas replacement region 3 a or the gas replacement region 3 c by the labyrinth portions 10 b and 10 c and is exhausted by the exhaust means 11. Further, the nitrogen gas existing in the pre-gas replacement region 3a or the gas replacement region 3c is prevented from leaking into the inlet opening 25a or the outlet opening 25b by the labyrinth portions 10a and 10d. The chamber 10 has a structure in which there is a margin in the gap 42 between the container 6 except for the labyrinth portion, which is advantageous when a nozzle for cleaning the inside of the chamber 10 such as CIP or SIP is provided. Although the chamber in the present invention is not used, the present applicant has already proposed and applied for the conveyance of containers by a magnetic conveyor and the narrowing of the passage by forming a labyrinth on the inlet and outlet sides. (Japanese Patent Application No. 2002-216287).
[0031]
In the present embodiment, the operation will be described. In this embodiment, the cross section of the container 6 and the cradle 16 for supporting the container 6 and the chamber 10 having a substantially similar cross section and the spraying of steam are combined. Is a feature. When the container 6 filled with cooked rice 7 is carried into the chamber 10 from the inlet opening 25a, first, nitrogen gas, which is an inert gas, is blown in the pregas replacement region 3a to perform pregas replacement. Next, steam is sprayed on the container 6 in the steam region 3b. Before the steam is blown, nitrogen gas is blown into the container 6, whereby the outside air entering the head space or the like in the container 6 is replaced with nitrogen gas. By performing gas replacement at the initial stage when the container 6 containing the cooked rice 7 travels in the chamber 10, the outside air containing oxygen can be removed in advance, and the gas replacement efficiency can be improved.
[0032]
The container 6 that has been subjected to the pre-gas replacement and the steam spraying is then sprayed again with nitrogen gas in the gas replacement region 3c while being transported in the chamber 10. When the lid 8 is heat-sealed out of the chamber 10 as it is after the steam is sprayed, it is discharged from the outlet opening 25b of the chamber 10 until the heat-sealing of the lid 8 is completed. As a result of the cooling of the steam, a part of the steam is condensed, and the inside of the container 6 is apt to be depressurized to draw in the outside air. However, in this embodiment, since the gas replacement with the nitrogen gas is performed again before leaving the chamber 10, such an outside air drawing phenomenon can be substantially eliminated, and the lid is closed in the sealing station 4 without the outside air being drawn. The container 8 containing the cooked rice 7 can be sealed with the material 8. Since moderate steam remains in the container 6, the steam condenses as it cools, so that an appropriate negative pressure is applied to the sealed container and a good-looking appearance can be secured on the package 9.
[0033]
In the chamber 10, since the inert gas is injected in the pre-gas replacement region 3a and the gas replacement region 3c before and after the steam is blown, the leakage of steam before and after the container transport direction is blocked by the inert gas. Therefore, it is possible to practically suppress the steam from leaking to the surrounding environment of the chamber 10 through a passage other than the exhaust means 11. Further, the container 6 containing the cooked rice 7 is sprayed with inert gas in the two pre-gas replacement areas 3a and 3c before and after traveling in the chamber 10, so that the contents are kept for a long time. It can be exposed to an inert gas to increase the removal rate of dissolved oxygen.
[0034]
A labyrinth structure is adopted at a connection portion between the pre-gas replacement region 3a and the gas replacement region 3c in the steam region 3b. Since the labyrinth portions 10b and 10c are at least two containers 6 and 6 in length, the labyrinth portions 10b and 10c exhibit an effect of preventing steam leakage regardless of the position where the container 6 occupies during transportation. be able to. Further, in the vicinity of the inlet opening 25 a and the outlet opening 25 b of the chamber 10, the shape of the chamber 10 is approximately aligned with the container 6, and the gap 41 formed between the container 6 and the chamber 10 is narrowed to reduce the labyrinth portion 10 b. , 10c are the same labyrinth portions 10a, 10d. The labyrinth portions 10a and 10d make it possible to reduce the leakage of nitrogen gas from the inside as much as possible, and also effectively prevent the outside air from entering the inside. Note that when the container 6 is remodeled (the size of the container is changed), there is an advantage that the change as the apparatus only needs to be changed for the labyrinth portions 10a to 10d.
[0035]
In the area where steam is sprayed by the steam injection means 27, that is, in the steam area 3b, the exhaust port 35 connected to the exhaust means 11 is formed below the container 6 to be transported. Can be efficiently exhausted outside the manufacturing room. Since the chamber 10 having a large amount of steam and a high degree of sealing is used, the amount of exhaust is determined by using the damper 38 so that the inside of the chamber 10 is slightly pressurized with respect to the pressure of the surrounding environment. preferable. Since an exhaust port 35 connected to the exhaust means 11 is formed at a lower position in the conveyance path of the container 6, priority is given to steam that does not serve for sterilization of contents or preheating of the seal due to a decrease in temperature below. And can be exhausted. Furthermore, since the exhaust port 35 and the exhaust means 11 are easily contaminated, it is preferable to exhaust the gas under the container 6 on the safety side for hygiene purposes. The exhaust means 11 may be a forced exhaust type. However, the exhaust means 11 is not necessarily limited to this, and the chamber 10 is naturally exhausted from the exhaust port 35 if the inside of the chamber 10 is kept in a moderately pressurized state and there is no wraparound of outside air from below. Natural exhaust means may be used. Furthermore, in order to prevent condensation of steam, it is preferable to keep the temperature of the exhaust means 11 at 100 ° C. or higher.
[0036]
【Example】
In the embodiment according to the present invention, the amount of nitrogen gas used in the pregas replacement region 3a per lane is 40 to 400 liters / minute, the steam is 0.5 to 80 kg / hour, and the nitrogen gas used in the gas replacement region 3c. The amount was 40-100 liters / minute. By performing gas replacement packaging under these conditions, the inside of the package is slightly negative pressure and looks good without impairing the appearance of the container, and the working environment of the manufacturing plant is prevented from becoming hot and humid. be able to. The contents to which the present invention can be applied are not limited to cooked rice, but can be applied to all gas replacement packaging for filling and sealing containers such as beverages and prepared dishes.
[0037]
【The invention's effect】
Since the gas replacement packaging method and apparatus according to the present invention are configured as described above, the container containing the contents has a cross-sectional shape substantially similar to the cross-sectional shape exhibited by the container and the cradle that supports the container. When the inside of the chamber is transported, first, steam is blown into the container, whereby the gas in the container is replaced by steam. When the container sprayed with steam is further transported in the chamber, gas replacement with an inert gas is performed. Therefore, it becomes easy to manage the leakage of steam from the chamber, and while enjoying the advantages of using steam, it is possible to prevent the surrounding environment from becoming hot and humid due to the leakage of steam. That is, by performing the replacement gas with an inert gas before leaving the chamber, the phenomenon of the outside air drawing due to the condensation due to the cooling of the steam from the outlet of the chamber to the completion of the sealing of the container and the decompression of the container inside is caused. It can be virtually eliminated. Since a part of the steam in the container is replaced by the inert gas, excessive decompression does not occur in the container sealed by the condensation of steam, and the appearance of the container after the sealing can be maintained. Moreover, the surface of the contents can be sterilized by steam by spraying steam. Furthermore, when the container is sealed by heat sealing of a packaging material such as a lid, the portion where heat sealing is planned is preheated by steam, and a good heat seal can be obtained.
[0038]
Further, since the steam and the inert gas (nitrogen gas) are sprayed in a chamber having a cross-sectional shape substantially similar to the cross-sectional shape exhibited by the container and the cradle that supports the container, the space in the chamber Is efficiently occupied by the container and the cradle, and the excess space is reduced in the chamber with good sealing performance. As a result, the team and the inert gas are efficiently used, the amount of use of the steam and the inert gas can be reduced, and the replacement efficiency of the steam and the inert gas can be improved. Furthermore, since intrusion of outside air can be prevented as much as possible, the sterility maintenance state can be improved.
[0039]
In the gas replacement packaging method and apparatus according to the present invention, the pre-gas replacement area and the gas replacement area by spraying an inert gas are arranged before and after the steam area, thereby preventing the steam from leaking from the inlet opening and the outlet opening of the chamber. can do. By forming the labyrinth portion between the steam region and the pregas replacement region and the gas replacement region, it is possible to prevent the steam from leaking to the pregas replacement region and the gas replacement region side. Furthermore, steam can be collected by forming an exhaust port connected to the exhaust means corresponding to the steam region. In addition, if outside air enters the inside of the package, the inside may be contaminated by fungi. According to the present invention, by mixing the container with contents in a highly sealed chamber, the outside air can be mixed. This can be prevented in advance. Further, the vicinity of the inlet opening and the outlet opening of the chamber is a labyrinth portion having a narrow gap between the container and the chamber, so that outside air can be effectively prevented from entering. Further, by providing the exhaust means at a position below the container transport path in the steam region, it is possible to prevent the outside air from entering the chamber.
[Brief description of the drawings]
FIG. 1 is a schematic side view of a main part of a gas replacement packaging apparatus according to the present invention.
2 is a cross-sectional view taken along line AA of the gas replacement packaging apparatus shown in FIG.
3 is a BB cross-sectional view of the gas replacement packaging apparatus shown in FIG.
FIG. 4 is a perspective view of a chamber disposed at a chamber station of the gas replacement packaging apparatus.
[Explanation of symbols]
1 Gas replacement packaging device 2 Aseptic space station
2a Transfer part 2b Contents filling part
3 Chamber station 3a Pre-gas replacement area
3b Steam area 3c Gas replacement area
4 Blocking station 5 Package removal station
6 Container 6a Body 6b Flange 7 Cooked rice
8 Lid 9 Packaging
10 Chamber 10a, 10b, 10c, 10d Labyrinth part
11 Exhaust means 12 Cover material roll
13 Cover material seal cut part 15 Magnetic conveyor
15a Drive sprocket 15b Driven sprocket
15c chain
15d Upper traveling part 15e Lower traveling part
16 cradle
20 Upper plate 21 Lower plate
22 Bottom portion 22a Standing portion 23 Shelf portion
24 Side wall plate 25a Inlet opening 25b Outlet opening
26, 28 Inert gas injection means 27 Steam injection means
30, 32 Magnet 31 Sliding material 33 Device frame
34 Guide rail
35 Exhaust port 36 Duct 37 Blower
40 Copying part 41, 42 Clearance

Claims (4)

A chamber having a cross-sectional shape substantially similar to the cross-sectional shape exhibited by the container containing the contents and the cradle that supports the container, and being transported inside by the transport means in a state where the container is supported by the cradle; Steam injection means for spraying steam on the container that is disposed in the chamber and passing through the chamber, and an inert gas that is disposed downstream of the steam injection means in the chamber and is passed through the chamber And an inert gas spraying means for spraying the steam, and a sealing means disposed after the outlet of the chamber for sealing the container, wherein the steam is sprayed by the steam spraying means in the chamber and the inert gas. The container passing through the boundary with the gas replacement region to which the inert gas is sprayed by the injection means; Gas replacement packaging device consists of the narrow and the labyrinth portion of the gap to be left between. A chamber having a cross-sectional shape substantially similar to the cross-sectional shape exhibited by the container containing the contents and the cradle that supports the container, and being transported inside by the transport means in a state where the container is supported by the cradle; Steam injection means for spraying steam on the container that is disposed in the chamber and passing through the chamber, and an inert gas that is disposed downstream of the steam injection means in the chamber and is passed through the chamber An inert gas spraying means for spraying the container, and a sealing means disposed next to the outlet of the chamber for sealing the container, wherein the chamber is passing through the chamber upstream of the steam spraying means. Pre-inert gas spraying means for spraying the inert gas on the chamber is disposed in the chamber by the steam spraying means. A pre-labyrinth portion in which a gap left between the container passing through the boundary between the steam region to which the steam is sprayed and the pre-gas replacement region to which the inert gas is sprayed by the pre-inert gas injection means is narrowed; Gas replacement packaging device consisting of To the chamber, in the steam region where the steam is sprayed by the steam injection means, below the transport path of the container, according to claim 1 or 2 consisting of the exhaust port is formed continuous to the exhaust means Gas replacement packaging device. The exhaust means is a natural exhaust means for performing natural exhaust from the exhaust port or a forced exhaust means for forcibly exhausting exhaust through the exhaust port, and the chamber is a pressurized state in which the pressure is slightly higher than the ambient environment The gas replacement packaging apparatus according to claim 3 , comprising:

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