JPH0530686B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vacuum packaging method for shrink-wrapping items to be packaged, such as bedding, apparel products, and clothing, using packaging bags made of resin film or the like.

(Prior Art) A conventional vacuum packaging method will be explained based on FIG. 5.

The pressure-resistant container 1 is composed of a lower container body 2 having an open upper surface and an upper container body 3 which can freely open and close the upper surface opening of the lower container body 2. A supply/exhaust port 4 is formed in the lower container body 2, and the supply/exhaust port 4 is connected via a hose 5 to a degassing device such as a vacuum pump (not shown). A packaging bag 8 containing a packaged object 7 such as a blanket is placed and stored in the pressure container 1 via a placing stand 6 having an appropriate thickness. Further, on the left side of the pressure vessel 1 as shown in the figure,
A sealing device 9 is provided for sealing the opening 8a of the packaging bag 8 by heat welding. This sealing device 9
A hot wire fixture 1 is attached to a vertically moving shaft 11 of a cylinder device 10 fixed to the lower container body 2.
The opening 8 of the packaging bag 8 is fixed to the opening 8 of the packaging bag 8 by the hot wire 13 fixed via the heat wire 2 and the heat wire receiver 15 made of rubber fixed to the upper container body 3 via the receiver fixture 14.
It is the one that sandwiches a.

In the vacuum packaging method of packaging using the vacuum packaging apparatus described above, with the upper container body 3 open, the packaging bag 8 containing the object to be packaged 7 is mounted inside the lower container body 2, and then the upper container body 3 is opened. body 3 to lower container body 2
(bonding process), then the inside of the pressure container 1 is made negative pressure with a vacuum pump to degas the packaging bag 8 (deaeration process), and then the sealing device 9 seals the packaging bag 8. The opening 8a is sealed (sealing process), and then the inside of the pressure-resistant container 1 is returned to the atmosphere (vacuum breaking process) to complete the packaging.

By the way, in the mounting process, the packaging bag 8
Occurrence of loosening and loosening is inevitable.

Further, in the deaeration step, there is a time difference between deaeration in the pressure container 1 and deaeration in the packaging bag 8, which may cause the shape of the packaging bag 8 to be distorted.

Further, in the vacuum breaking process, the pressure inside the pressure container 1 returns to the atmospheric pressure state, but since the inside of the packaging bag 8 is under negative pressure, the packaging bag 8 rapidly shrinks and becomes in a tight state. Therefore, wrinkles and irregularities in the shape of the packaging bag 8 that housed the object to be packaged 8 due to loosening and sagging during the mounting process develop due to shrinkage, and wrinkles, changes in shape, and irregularities occur significantly. In some cases, the product value may be lost.

Therefore, conventional methods have been used to prevent shrinkage and deformation by arranging a gas filling device inside the pressure container, injecting inert gas into the packaging bag, and bringing the negative pressure inside the packaging bag close to atmospheric pressure. is also taken, but
In this method, the cost increases due to the inclusion of gas, and the volume of the packaged object cannot be reduced.

Furthermore, as described in Japanese Patent Application Laid-Open No. 61-123005, a pressure plate that presses the packaged items stored in the packaging bag in the thickness direction is provided in the pressure container to compress the packaged items. At the same time, a vacuum packaging apparatus has been proposed that prevents the occurrence of wrinkles and changes in shape of the packaged items and packaging bags. According to this method of pressing with a pressure plate, it is possible to reduce the occurrence of wrinkles and changes in shape during the vacuum breaking process. However, it is not possible to completely prevent wrinkles and irregularities in shape that develop and occur in the vacuum breaking process after the sealing process due to loosening and loosening of the packaging bag that occurs during the mounting process.

In addition, as described in Japanese Patent Application Laid-open No. 59-51019, there is a method in which a pressure plate operated by a cylinder inside an airtight chamber of a container presses an item to be packaged in a packaging bag to a predetermined thickness. It has been known.

(Problems to be Solved by the Invention) As mentioned above, in the conventional vacuum packaging method, the vacuum breaking process begins immediately after the sealing process, so even if the pressure plate presses the packaged items stored in the packaging bag. However, there was a problem in that it was not possible to sufficiently prevent wrinkles that developed or occurred due to shrinkage in the vacuum breaking process due to loosening or loosening of the packaging bag.

The present invention aims to solve these problems, and aims to provide a vacuum packaging method that can reliably prevent the occurrence of wrinkles and disturbance of the shape of packaging bags containing items to be packaged. It is something to do.

(Means for Solving the Problems) The vacuum packaging method of the present invention includes a mounting step of mounting a packaging bag containing an object to be packaged into a pressure-resistant container, and after this mounting step, creating a negative pressure in the pressure-resistant container. a degassing step for deaerating the inside of the packaging bag; a sealing step for sealing the opening of the packaging bag after the degassing step;
After this sealing process, there is a vacuum breaking process in which the inside of the pressure container is brought to atmospheric pressure, and after the installation process is completed, the packaged items stored in the packaging bag are placed on a pressure plate from the beginning of the degassing process to the end of the vacuum breaking process. In a vacuum packaging method that includes a pressing step of pressing in the thickness direction, after the sealing step and before the vacuum breaking step, the inside of the pressure container is degassed to make the inside of the pressure container further negative pressure. It has an air process.

(Function) In the vacuum packaging method of the present invention, a packaging bag containing an object to be packaged such as bedding is installed in a pressure-resistant container in a mounting step, and then, in a pressing step, the object to be packaged is moved in the thickness direction with a pressure plate. While pressing, the inside of the pressure container is made negative pressure in the degassing process to deaerate the inside of the packaging bag. Next, the opening of the packaging bag is sealed in the sealing process, and then the pressure is reduced in the re-degassing process. The inside of the pressure container is degassed to further create a negative pressure inside the pressure container. At this time, since the opening of the packaging bag has already been sealed, a pressure difference occurs between the inside of the packaging bag and the inside of the pressure-resistant container, and the degree of vacuum is higher inside the pressure-resistant container, causing the packaging bag to expand. do. This expansion removes wrinkles and changes in the shape of the packaging bag containing the packaged items, which are caused by loosening and loosening of the packaging bag caused by the pressure applied by the pressure plate, and which occur during the degassing process. . Furthermore, in the vacuum breaking step after the re-degassing step, the inside of the pressure container is returned to atmospheric pressure, and packaging is completed. In the re-degassing process, the packaging bag is pressed and held in a state where the wrinkles are smoothed out by a pressure plate, so in the vacuum breaking process, wrinkles and shape changes develop or occur in the packaging bag containing the packaged item. is prevented.

(Example) Hereinafter, one example of the vacuum packaging method of the present invention will be described in the first example.
This will be explained based on the figures.

First, the configuration of the vacuum packaging apparatus used in this method will be explained.

Reference numeral 21 denotes a pressure-resistant container, and the pressure-resistant container 21 includes a lower container body 22 that is formed in a box shape with an open top and is fixed, and a lower container body 22 that is formed in a flat plate shape and is removably mounted on the upper surface opening of the lower container body 22. and an upper container body 23 which closes the upper surface opening in a freely openable and closable manner, and a sealing pad is provided on the lower peripheral edge of the upper container body 23 to be airtightly pressed against the upper peripheral edge of the lower container body 22. King 24 is fixed. Further, an air supply/exhaust port 25 is formed on the rear side (right side in the drawing) of the lower surface of the lower container body 22, and a hose 26 is connected to the air supply/exhaust port 25. The other end of this hose 26 is
Although not shown, it is connected, for example, to a vacuum pump as a deaerator via a switching solenoid valve.

Further, a plurality of pressurizing cylinder devices 31 are provided below and externally to the lower container body 22, for example, in the front, rear, left and right directions. Next, this pressurizing cylinder device 31 will be explained.

A cylinder main body 32 is coupled and fixed to the lower surface of the lower container body 22, and these lower container bodies 2
The joint between the cylinder body 32 and the cylinder body 32 is kept airtight by a joint O-ring 33. Also,
A communication port 35 is formed in the cylinder bottom plate 34 fixed to the lower opening of the cylinder body 32. Further, a piston 36 is fitted into the cylinder body 32 so as to be slidable up and down, and this piston 36 is always urged downward by a cylinder spring 37. Note that the piston 36
A piston O-ring 38 fixed to the outer peripheral surface of the cylinder body 32 is pressed against the inner peripheral surface of the cylinder body 32 in an airtight and slidable manner. And the piston 36
A cylinder shaft 39 fixed to the lower container body 22 passes through the lower surface of the lower container body 22 in a vertically slidable manner and projects into the lower container body 22. In addition, the seal O-ring 40 which is press-contacted with the lower container body 22 and the cylinder body 32 and slidably press-contacted with the cylinder shaft 39 ensures airtightness between the inside of the lower container body 22 and the cylinder body 32. Retained.

Furthermore, a cylinder control switching solenoid valve 46 communicates with a connection port 41 formed above the sliding range of the piston 36 in the cylinder body 32 via pressure-resistant joints 42, 43 and connection pipes 44, 45. It is connected. The switching solenoid valve 46 is a three-way switching valve, and connects the connection port 41 to either the negative pressure side opening or the atmospheric pressure side opening. The negative pressure side opening is connected to a vacuum pump, and
The atmospheric pressure side opening is open to the atmosphere.

Further, boss bodies 51 are located in the lower container body 22 and fitted onto the cylinder shafts 39 of the respective pressurizing cylinder devices 31 from above, and on these boss bodies 51, one plate-shaped A pressure plate supporting rigid body 52 is fixed horizontally. and,
A pressure plate 55 is attached to a horizontal support shaft 54 supported by a support fitting 53 erected in the center of the support rigid body 52.
A vertical bearing fitting 56 is rotatably supported at the center of the holder. That is, the pressure plate 55 is
It is supported so as to be able to swing up and down using a support shaft 54 as a fulcrum. On the other hand, the pressure plate 55 is connected to the lower surface of the upper container body 23 via a plurality of pressure receiving springs 57.
A pressure receiving plate 58 facing the is supported.

Further, a sealing device 61 is provided on the front side (left side in the figure) of the pressure-resistant container 21 . Next, this sealing device 61 will be explained.

A cylinder body 63 of a hot-wire action cylinder device 62 is fixed to the lower front side of the lower container body 22. Note that this hot wire operation cylinder device 62 has a similar structure to the pressurized cylinder device 31, and operates through another switching solenoid valve (not shown) that operates independently of the switching solenoid valve 46.
Connected to a vacuum pump. A vertically movable cylinder shaft 6 protrudes into the lower container body 22 of the hot wire action cylinder device 62.
4 is fitted with a hot wire fixture 65 from above,
A hot wire 66 is fixed onto this hot wire fixture 65. On the other hand, on the lower front side of the upper container body 23,
A hot wire receiver 68 made of silicone rubber, which faces the hot wire 66 from above and comes into contact with the hot wire 66 in a movable manner, is fixed via a receiver fixture 67.

Furthermore, an opening holding device 71 is located in the lower container body 22 near the front of the sealing device 61.
is provided. Next, this opening holding device 71 will be explained.

A fixing metal fitting 72 having a generally U-shaped side surface is fixed to the bottom surface of the lower container body 22, and a rail groove 73 extending in the left-right direction is formed in the upper surface of the fixing metal fitting 72. And this rail groove 7
A pair of left and right first sliders 74 are supported on the rail groove 73 by screws 75, respectively.
It can be fixed at any position. Further, a pair of left and right second sliders 76 are supported in the rail groove 73 so as to be slidable left and right, respectively, and are located between the two first sliders 74. Insertion pins 77 each having an inverted L-shape and whose tips protrude rearward are provided. Then, the adjacent first slider 7
4 and the second slider 76 is a bag tension spring 7.
8 are each strung up.

Next, a vacuum packaging method using the vacuum packaging apparatus described above will be explained.

The first step is a mounting step in which the packaging bag 82 containing the packaged object 81 such as a folded blanket is mounted inside the pressure container 21. Note that the packaging bag 82
is made of a heat-fusible material such as polyethylene resin film.

In the mounting process, with the upper container body 23 open, the object to be packaged 81 is placed into the packaging bag 82 through its opening 82a, the object to be packaged 81 is placed on the pressure plate 55, and the object to be packaged 81 is placed on the pressure plate 55, and 82a is placed on the hot wire 13, and a pair of left and right insertion pins 77 of the opening holding device 71 are inserted into both sides of the opening 82a of the packaging bag 82. Note that with the bag tension spring 78 at its natural length, both first sliders 74 are slid to a position where the distance between both insertion pins 77 is about 5 cm larger than the length of the opening 82a of the packaging bag 82, and the screws are removed. Tighten 75 to secure it. Therefore, in the state where both insertion pins 77 are inserted, both insertion pins 77 are urged in the direction of separation by the bag tension spring 78, and the opening 82a of the packaging bag 82 is
Since tension is applied and expanded in the left-right direction, it is held open by a width equal to the diameter of the insertion pin 77 and without wrinkles.

A second slider 7 provided with an insertion pin 77
Since the first slider 74 with a spring 78 stretched between it and the second slider 76 is slidable, the opening 82a of the packaging bag 82 to the insertion pin 77
Furthermore, by attaching the opening 82a to the insertion pin 77 in this manner, even if the packaged object 81 has a complicated shape, the opening 82a can be easily attached to the hot wire 66. Furthermore, by adjusting the position of the first slider 74, the bag tension spring 7
By adjusting the movable range of the insertion pin 77 of the second slider 76 whose movement is suppressed by 8, it is possible to easily accommodate differences in the size of the packaging bag 82, and the The biasing force can also be set to an appropriate value.

Then, the upper container body 23 is placed on the lower container body 22. In this state, both container bodies 22, 23
A vacuum chamber 21a is formed within a pressure-resistant container 21 consisting of.

In addition, in the mounting process, the connection port 41 of the pressurized cylinder device 31 is kept in a state of being communicated with the atmosphere by the solenoid valve 46. In this state, as shown in FIG. 1, the biasing force of the cylinder spring 37 causes the piston 36 and the cylinder shaft 39 to
is located below, and therefore the pressure plate 55 is also located below.

Next comes the degassing process.

In the deaeration step, the vacuum pump is driven to evacuate from the air supply/exhaust port 25 to create a negative pressure in the vacuum chamber 21a, and to evacuate the inside of the packaging bag 82. As the pressure inside the vacuum chamber 21a becomes negative, the connection between the upper container body 23 and the lower container body 22 becomes stronger. Further, as described above, since the opening 82a of the packaging bag 82 is held open by the opening holding device 71, air flows out smoothly from inside the packaging bag 82.

Also, at the beginning of the degassing process, the switching solenoid valve 4
6 is activated to connect the connection port 41 of the pressurized cylinder device 31 to the vacuum pump. Then,
The space above the piston 36 in the cylinder body 32 rapidly approaches a vacuum state, and as shown in FIG.
9 is pushed up by atmospheric pressure. Furthermore, the supporting rigid body 52 is lifted by each shaft 39 of the plurality of pressurizing cylinder devices 31, and the pressurizing plate 55 connected to the central portion of the supporting rigid body 52 by a support shaft 54 is lifted. And this pressure plate 55
and a pressure receiving plate 5 supported via a pressure receiving spring 57.
8 sandwich the packaged object 81 housed in the packaging bag 82 and press it in the thickness (height) direction. This results in
Degassing within the packaging bag 82 is promoted, expansion and deformation of the packaging bag 82 is prevented, and the occurrence of wrinkles in the packaging bag 82 is prevented. Moreover, the packaged object 81 is compressed in the thickness direction and its shape is adjusted.

Moreover, since the pressure plate 55 is driven by the pressure cylinder device 31 that operates independently of the pressure within the vacuum chamber 21a, it is possible to press the packaged object 81 with sufficient force from the beginning of the degassing process. Therefore, the occurrence of wrinkles and disturbance of the shape are reliably prevented.

Moreover, since the pressure receiving plate 58 which sandwiches the object 81 between the pressure plate 55 and the pressure receiving plate 58 is supported by a plurality of springs 57, even if the stroke of the pressure plate 55 is constant, the shape and thickness of the object 81 can be adjusted. As each spring 57 expands and contracts depending on the pressure, the pressure receiving plate 58
is securely brought into close contact with the upper surface of the object to be packaged 81, and the object to be packaged 81 is pressed with an appropriate force. For example, even if the packaged item 81 is thick, excessive force will not be applied to the packaged item 81 and breakage will occur, and the packaged item 81 will not be damaged.
Even if the packaging bag 82 is thin, wrinkles will not occur in the packaging bag 82 due to insufficient pressurization.

By the way, it is difficult to make all the operations of the plurality of pressurizing cylinder devices 31 on the front, rear, left and right sides completely the same, and it is normal for there to be some time difference in the operations. Therefore, if a plurality of cylinder shafts 39 are directly connected to the pressure plate 55 that directly presses the object to be packaged 81, the pressure plate 55
does not operate, and one of the pressurizing cylinder devices 31
If one of them fails, there is a risk that the pressure plate 55 will not operate. However, in the above embodiment,
The lifting force of the plurality of cylinder shafts 39 is
Since the lifting force is concentrated on the support shaft 54 at the center of the support rigid body 52 and transmitted to the pressure plate 55 via this support shaft 54, the lifting force is uniformly transmitted to the pressure plate 55, and the packaged object 81 is also uniformly Pressed by

Furthermore, assuming that the pressure plate 55 and the pressure receiving plate 58 cannot be in a state other than the horizontal state, if the shape of the packaged object 81 is different from front to back and left to right, the thin part of the packaged object 81 will be under-pressurized. On the other hand, there is a risk of excessive pressurization in thick parts. However, the pressure receiving plate 58 supported by a plurality of springs 57 on the upper side tilts to cope with the difference in the thickness of the packaged object 81 in the front, back, left and right sides.
Also on the lower side, the pressure plate 55 supported by the support shaft 54 so as to be vertically swingable is tilted to accommodate the packaged object 81.
The entire area is pressed evenly.

Then, after the inside of the vacuum chamber 21a and the packaging bag 82 are almost evacuated, a sealing process is performed.

In the sealing process, the switching solenoid valve is operated to connect the connection port of the hot wire operating cylinder device 62 to the vacuum pump, the cylinder shaft 64 is raised, and the hot wire 13 is inserted into the hot wire receiver across the opening 82a of the packaging bag 82. It is pressed against the body 68. At the same time, the heating wire 66 is energized, and the opening 8 of the packaging bag 82
2a is heat welded and sealed. At this time, the pressure plate 55 prevents the packaging bag 82 from expanding and deforming in the degassing process, and the opening 8 of the packaging bag 82
2a is held by the opening holding device 71, and the opening 82a of the packaging bag 82 is prevented from shifting and wrinkles, so sealing in a wrinkled state is reliably prevented and the opening 82
a is reliably sealed.

Next is the re-degassing process.

In the re-degassing process, similarly to the degassing process, the vacuum pump is driven to exhaust air from the supply/exhaust port 25, degassing the vacuum chamber 21a, and further creating a negative pressure in the vacuum chamber 21a. be converted into
At this time, since the packaging bag 82 containing the packaged object 81 in the previous sealing process has already been sealed,
The inside of this packaging bag 82 is not made negative pressure, but is maintained at the atmospheric pressure during the sealing process. Therefore, the air pressure inside the vacuum chamber 21a is lower than that inside the packaging bag 82, so
The packaging bag 82 is in an expanded state. In this state, the packaging bag 82 pressed by the pressure plate 55 loosens,
Wrinkles and irregular shapes caused by loosening will be removed by expansion. That is, it is possible to reliably eliminate wrinkles and irregularities in the shape of the packaging bag 82 caused by loosening and loosening of the packaging bag 82 during the mounting process and initial pressurization, both on the pressure plate 55 side and on the pressure receiving plate 58 side.

Note that re-deaeration is performed for 5 to 10 seconds after sealing, and the pressure inside the vacuum chamber 21a is reduced to 25 to 35% of the atmospheric pressure inside the packaging bag 82.
Create negative pressure. That is, the degree of vacuum in the vacuum chamber 21a is set to be 100 to 150 Torr higher than the degree of vacuum at the time of sealing.
A difference in the degree of vacuum of this magnitude can provide a sufficient wrinkle smoothing effect.

Next is the vacuum breaking process.

In the vacuum breaking process, the supply/exhaust port 25 of the pressure container 21 is communicated with the atmosphere, and the inside of the vacuum chamber 21a is brought to atmospheric pressure. At this time, the sealed packaging bag 82
Since the inside is in a vacuum state, this packaging bag 82
And the packaged object 81 shrinks and becomes in a close contact state,
Since the object to be packaged 81 is pressed by the pressure plate 55, the generation of wrinkles and disturbance of the shape during storage deformation are prevented.

Moreover, as explained earlier, the pressure plate 55
Since this presses the packaged object 81 with a force independent of the pressure within the vacuum chamber 21a, the packaged object 81 can be pressed with sufficient force until the end of the vacuum breaking process. Therefore, even in the vacuum breaking process, wrinkles and shape disturbances are reliably prevented.

Furthermore, even if the object to be packaged 81 shrinks, the pressure receiving plate 58 that sandwiches the object to be packaged 81 with the pressure plate 55 is supported by the spring 57, so that the object to be packaged
1 is maintained.

As mentioned above, in the re-degassing process before the vacuum breaking process, the packaging bag 82 containing the object to be packaged 81 is no longer wrinkled or has any irregularities in shape, so the wrinkles that had occurred before the vacuum breaking process are gone. Moreover, the disordered shape does not develop and expand as the packaged object 81 and the packaging bag 82 shrink.
Therefore, together with the action of the pressure plate 55, the generation of wrinkles and changes in shape can be more reliably prevented even in the vacuum breaking process.

Furthermore, when the inside of the vacuum chamber 21a is brought to atmospheric pressure,
The bonding force between the upper container body 23 and the lower container body 22 weakens, and at this point, if the pressurizing force is applied to the pressurizing plate 55 by the pressurizing cylinder device 31, the upper container body 23 will be in an open state with an impact. However, this impact is absorbed by the spring 57 between the upper container body 23 and the pressure receiving plate 58.

Next, open the upper container body 23 and open the packaged object 8.
The packaging bag containing 1 is taken out and the packaging work is completed.

According to the above method, it is easy to attach the packaging bag 82 containing the object to be packaged 81, the upper container body 23 and the lower container body 22 are connected by creating a negative pressure in the vacuum chamber 21a, and the pressure-resistant container 21 and the packaging bag 82 are easily attached. Since the negative pressure inside the bag 82 and the pressing of the packaged object 81 by the pressure plate 55 are automatically performed, the entire process up to the completion of packaging can be carried out efficiently and in a short time. In addition, it is possible to obtain a package that has a small thickness, a small volume, and a good appearance without wrinkles over the entire surface including the sealing part.

Further, since the pressure plate 55 that presses the object to be packaged 81 is driven by the pressure cylinder device 31 operated by air pressure, this pressure cylinder device 31
can be operated by a vacuum pump that makes the inside of the vacuum chamber 21a negative pressure.

Further, in the re-degassing step, since the same vacuum pump as used in the degassing step can be used for degassing, special equipment is not required for the re-degassing step, and the cost can be reduced.

Note that the pressurizing cylinder device 31 may be arranged in the upper and lower portions of the pressure-resistant container 21, as long as the advancing and retreating direction of the cylinder shaft 39 coincides with the compression direction of the packaged object 81.

Further, in the above embodiment, the pressurizing cylinder device 3
The pressure plate 55 driven by 1 is located below the packaged object 81, and the pressure receiving plate 58 supported by the spring 57 is located above. 58 may be located on the lower side.

(Effects of the Invention) According to the present invention, the pressure inside the pressure container is further reduced to negative pressure in the re-degassing step after the sealing step and before the vacuum breaking step. Wrinkles and irregularities in the packaging bag's shape that occur during the degassing process can be eliminated by the expansion of the packaging bag in the re-degassing process. Because pressure is applied in the same direction, wrinkles and
It is possible to prevent shape deformation and obtain a package with good appearance, and the effect of preventing wrinkles and shape disturbance due to the pressure plate can be made even more effective by the re-degassing step. Further, in the re-degassing step, since degassing can be performed using the same deaerator as used in the degassing step, no special equipment is required for the re-degassing step, which can be done at low cost.

[Brief explanation of drawings]

FIG. 1 is a vertical side view showing an apparatus used in an embodiment of the vacuum packaging method of the present invention, FIG. 2 is a vertical side view showing the object to be packaged being pressed by the same pressure plate, and FIG. 3 is a side view of the same as the above opening. FIG. 4 is a cross-sectional front view of the vicinity of the opening holding device, and FIG. 5 is a vertical cross-sectional side view showing an example of a conventional vacuum packaging device. 21... Pressure-resistant container, 81... Item to be packaged, 82...
...Packaging bag, 82a...opening.

Claims (1)

[Scope of Claims] 1. A mounting step in which a packaging bag containing an object to be packaged is mounted in a pressure-resistant container, and a degassing step in which the pressure inside the pressure-resistant container is reduced to negative pressure to degas the inside of the packaging bag after this mounting step. a sealing step of sealing the opening of the packaging bag after this degassing step; a vacuum breaking step of bringing the inside of the pressure container to atmospheric pressure after this sealing step; and a degassing step after completing the mounting step. A vacuum packaging method comprising a pressing step of pressing a packaged item stored in a bag to be packaged in the thickness direction with a pressure plate from the beginning of the process to the end of the vacuum breaking step, after the sealing step and before the vacuum breaking step. A vacuum packaging method comprising a re-degassing step of deaerating the pressure container and further reducing the pressure inside the pressure container.