JP2000142623A - Gas filling-packaging machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a gas replacement rate in a packaged body by providing a nozzle which jets an inert gas and replace air in a cylindrical section with the inert gas, and arranging the jetting port of the nozzle in such a manner that the inert gas may be jetted diagonally inside to the advancing direction of the cylindrical section from a joint on a film side edge section. SOLUTION: This lateral gas filling-packaging machine has a vertical sealing section 20 which joins the side edges f, f on both sides of a film F, and vertically seals the joint S, an end sealing section 30 which laterally seals the tip end of a cylindrical section T being formed by the vertical seal, and at the same time, cuts the tip end and forms a packaged body P, and a nozzle 50 or the like, which introduces an inert gas G in the cylindrical section T. In this case, for the nozzle 50, the jetting port 51 is fitted in a manner to be tilted so that the inert gas G may be jetted diagonally inside to the advancing direction of the cylindrical section T from the joint S. Also, the jetting port 51 of the nozzle 50 is molded to be flat, and is arranged in such a manner that the longer diameter may be extended in the width direction of the joint S. By this constitution, an efficient gas replacement with the inert gas G becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas filling for improving the replacement ratio of air and inert gas in a package filled with an inert gas together with an article and reducing the waste of the inert gas during the filling. Related to packaging machines.

[0002]

2. Description of the Related Art In packaging articles such as foods and pharmaceuticals, gas-filled packaging is performed in which the atmosphere in a wrapper is replaced with an inert gas such as nitrogen gas or carbon dioxide gas to prevent oxidation by air. This gas-filled packaging is generally performed continuously using a gas-filled packaging machine, and the widthwise side edges are aligned while running the band-shaped film as the packaging material in the length direction, and the seams are continuously vertically sealed. Then, the tip of the formed tubular portion is laterally sealed to form a bag portion at the tip of the tubular portion, and articles are intermittently introduced toward the bag portion from the open end side of the tubular portion. At the same time, an inert gas is introduced into the tubular portion from the same open end to replace the air in the tubular portion and the bag portion with the inert gas, and the rear end of the bag portion into which the article is introduced and gas-replaced is introduced. Transversely seal to form one unit of package. The gas filling and packaging machines are roughly classified into a vertical type and a horizontal type.
The vertical type is a type in which the tubular portion is formed vertically and articles are dropped into a bag formed at the lower end thereof, and is suitable mainly for packaging bulk goods. On the other hand, the horizontal type is a method of transporting articles in the horizontal direction, and is often used for packaging solid products having a certain shape or fragile articles.

[0003]

As described above, the gas filling and packaging machine, whether it is a vertical type or a horizontal type, introduces an inert gas into a cylindrical portion having one open end. Therefore, the inert gas is diffused from the open end, and more gas than is required for gas replacement is consumed. Therefore, reduction of the amount of the emitted gas has been an issue. In addition, even if an inert gas is introduced into the cylindrical portion, it has been pointed out that the replacement with air does not proceed smoothly, and the rate of replacement between the air in the package and the inert gas is low.

[0004] In order to solve these problems, for example, in a vertical gas filling and packaging machine, Japanese Patent Application Laid-Open No. 58-63351 discloses that a bulk product is intermittently placed on a tubular portion of the packaging film from the open end side. The chute pipe to be inserted is inserted, and the inert gas is blown from the chute pipe at the article input port while always overflowing, and the air replaced with the inert gas in the bag portion and the inert gas mixed with the air are injected into the chute pipe. A method has been proposed for discharging from the gap between the tip and the cylindrical portion. Japanese Patent Application Laid-Open No. 10-53217
The publication discloses that an article is intermittently charged into a laterally sealed bag at the lower end of a tubular portion, and an inert gas injection nozzle is inserted through the tubular portion up to the upper portion of the bag to discharge the inert gas into the bag. A method has been proposed in which the injection of the inert gas is performed separately before and after the injection of the article. Further, Japanese Utility Model Laid-Open Publication No. 2-66404 proposes a method of introducing an inert gas by inserting an annular nozzle from an upper open end of a cylindrical portion.

In a horizontal gas filling and packaging machine, Japanese Utility Model Publication No. 55-44724 discloses a method of inserting an inert gas injection nozzle deeply into the vicinity of a bag formed at the tip of the cylindrical portion of the packaging film. is suggesting. Further, Japanese Patent Application Laid-Open No. 63-203522 proposes a method of intermittently supplying an inert gas from the injection nozzle in order to further improve the replacement ratio between the air and the inert gas.

However, in any of the above methods, excessive emission of the inert gas from the open end of the cylindrical portion is unavoidable, and the replacement ratio of the inert gas with air is not sufficient. Moreover, in each of the above proposals, operating conditions for optimizing the amount of inert gas used and the gas replacement rate are not sufficiently disclosed. Further, particularly in a horizontal gas-filled packaging machine, the method of inserting the nozzle deeply into the vicinity of the bag at the tip of the tubular portion requires a space for inserting the nozzle between the article to be introduced and the inner wall of the tubular portion. Therefore, when packaging individual products, it is not possible to pack the packaging material in close contact with the article, and if this nozzle insertion space is narrowed, the nozzle comes into contact with the article in the cylindrical part and the spacing between the articles shifts, resulting in poor sealing. This causes problems such as causing troubles in continuous packing. The present invention has been made in order to solve the above-described problems, and accordingly, an object of the present invention is to provide a solid product using a horizontal gas-filled packaging machine, in which an inert gas injection nozzle does not hinder the packaging operation. It is an object of the present invention to provide a gas-filling and packaging machine capable of tightly packing the same, reducing the consumption of inert gas, and improving the gas replacement rate in the package.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is to roll a wrapping film in the width direction while running the film in the length direction, and continuously seal the seam vertically. Forming a tubular portion, forming a bag portion at the distal end of the tubular portion by transversely sealing the tip of the formed tubular portion in the transverse direction, and moving from the open end side of the running tubular portion to the bag portion. In a packaging machine that intermittently introduces articles so that the bag portion accommodates one unit of the article and forms a one-unit package by horizontally sealing the rear end of the bag portion in which the article is accommodated, A nozzle for inert gas injection for injecting an inert gas into the cylindrical portion and replacing air in the cylindrical portion and the bag portion with an inert gas,
A gas filling and packaging machine is provided, wherein the injection port of the nozzle is disposed so as to inject an inert gas from a seam of the film side edge toward an obliquely inward direction of the cylindrical portion in the traveling direction. I do.

As described above, when the inert gas is injected from the seam of the film side edge toward the obliquely inward in the traveling direction of the cylindrical portion, the inert gas flows along the vertical seal in front of the cylindrical portion. , Most of which is folded at the rear end of the article placed thereabove, forming a circulating flow in the space formed in the gap between the article and the article at the joint position, with the air in this space It is released from the gap in the film behind the seam. That is, since a circulating flow of the inert gas is formed in a narrow space between the articles, the gas is efficiently replaced, and the amount of gas that is not introduced into the cylindrical portion and is wasted is reduced.

In the above, it is preferable that the strip-shaped film is run in the horizontal direction, and articles are introduced into the tubular portion at predetermined intervals from the open end of the tubular portion. That is, the horizontal type allows the articles to be transported in the horizontal direction, and allows individual products and fragile articles to be packed without any trouble.

In the above, the width of the seam at the side edge of the film is in the range of 5 mm to 20 mm, and the nozzle has a flat jet port extending in the width direction of the seam. It is preferable that the width of the seam is 0.5 times to 1.5 times the width of the seam, and the short diameter of the injection port is 1 mm to 3 mm. If the width of the seam is less than 5 mm, the sealing strength and the degree of sealing will be insufficient. If the width of the seam exceeds 20 mm, the sealing strength and the degree of sealing will not be particularly improved, and the appearance of the package will be impaired. The injection port of the nozzle is flat, and the major axis extending in the width direction of the seam is 0.5 times or more the width of the seam.
When the diameter is within 1.5 times and the minor axis is within the range of 1 mm to 3 mm, the amount of inert gas radiated to the outside is reduced, and the circulation of the inert gas in the cylindrical portion is performed more smoothly. As a result, the gas replacement rate is improved.

[0011] In the above, the feed gas pressure of the inert gas injected from the nozzle is in the range of ^{0.5kg / cm 2 G~4kg / cm 2} G, the feed gas flow rate 5 liter / min to 40 l / Minutes. As a result of testing gas supply conditions when performing gas-filling and packaging using the gas-filling and packaging machine of the present invention, to reduce the consumption of inert gas and improve the gas replacement rate in the package, the supply gas pressure It has been found that it is effective to make the flow rate relatively low and to minimize the supply gas flow rate. However, if the supply gas pressure is less than 0.5 kg / cm ² G and / or the supply gas flow rate is less than 5 liters / minute, the space of the cylindrical portion may not be sufficiently replaced with the inert gas. When the supply gas pressure exceeds 4 kg / cm ² G, the circulating flow in the cylindrical portion is disturbed, and the gas replacement ratio tends to decrease. If the supply gas flow rate exceeds 40 liters / minute, the amount of gas directly dissipated from the joint to the outside increases, resulting in an increase in loss.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a horizontal gas filling and packaging machine according to one embodiment of the present invention. In FIG. 1, the gas-filled packaging machine generally includes a film transport unit 10 that transports a band-shaped film F for packaging in the longitudinal direction, and inner edges of the film contact side edges f, f on both sides of the band-shaped film F. And a vertical sealing portion 20 for continuously vertically sealing the seam S. The tip of a cylindrical portion T formed by the vertical sealing is transversely sealed and cut in a transverse direction, and the package P for each unit is cut. An end seal portion 30 forming
The articles M are placed at predetermined intervals from the open end D side of the cylindrical portion.
And a nozzle 50 for introducing an inert gas G into the cylindrical portion T.

The film transport section 10 guides the belt-like film F fed from a film roll (not shown) toward the vertical sealing section 20, and leaves the belt-like film F at the side edges f, f. Member 12, which rolls the cylindrical portion T of the rolled strip film horizontally toward the end seal portion 30, and a cylindrical portion into which the article M is inserted together with the lower conveyor 13. And an upper conveyor 14 which conveys the sheet T toward the end seal portion 30.

The vertical seal portion 20 is a set of two sets which transport the belt-shaped film conveyed while aligning the side edges f, f so that the inner surfaces of the film are in contact with each other, and pulling the seam from both sides while pulling in the length direction. Nip rolls 21, 21, and 22,
22, and heat sealers 23, 23 mounted between the two sets of nipping rolls and continuously heat-sealing with the side edges f, f sandwiched from both sides.

The end seal portion 30 transversely heat seals the rear end portion of the bag portion B formed at the front end of the cylindrical portion from both the upper and lower sides, and a strip film along the center line of the heat seal width. Cutters 31, 31 for cutting
And the unloading conveyor 32 for unloading the separated package P.
It consists of

The article carry-in section 40 has a front end inserted into the inside of the bottom surface of the cylindrical portion T, and a conveying plate 41 on which the group of articles M is placed, and a group of articles installed above the conveying plate 41. M
... at equal intervals and at a speed equal to the traveling speed of the tubular portion T into the tubular portion T. The sending device 42 is configured such that claws 43 are attached to a belt at equal intervals, and the claws 43 push articles one by one and send the articles into the cylindrical portion at equal intervals.

The nozzle 50, as shown in detail in FIG.
The injection port 51 is mounted so as to be inclined such that the inert gas G is injected from the seam S of the film side edges f, f obliquely inward in the traveling direction of the tubular portion T. The injection port 51 of this nozzle is formed flat, and is arranged so that its major axis extends in the direction of the width W of the joint S. In this embodiment, the width W of the joint S is 18 mm, the major axis of the injection port 51 is equal to the width of the joint S, 18 mm, and the minor axis is 3 mm.
mm.

The gas filling and packaging machine of the above embodiment can be operated as follows. First, a belt-like film F is unwound from a film roll (not shown), and the leading end thereof is pulled by hand and wrapped around guide rolls 11, 11.
2, the strip-shaped film is rolled into a cylindrical shape while leaving the side edges f, f each having a width of 18 mm. Next, the belt-shaped film is pulled out onto the lower conveyor 13, and the side edges f, f are aligned so that the inner surfaces of the films are in contact with each other, and the aligned side edges f, f are sequentially sandwiched between the rolls 21, 21 and the heat sealer 2.
3, 23, and between the sets of the sandwiching rolls 22, 22.
Further, the leading end of the belt-like film is drawn out onto the carry-out conveyor 32 between the lower conveyor 13 and the upper conveyor 14 and between the seal cutters 31 of the end seal portion 30.

In this state, the injection port 51 of the nozzle
At the joint S where the side edges f, f are joined. The injection port 51 is disposed so as to fit exactly within the width W of the side edge f at the seam S, and the injection port 51 is directed obliquely inward in the traveling direction of the tubular portion T. .

Next, the film transport section 10 and the vertical seal section 20
And actuate. Then, the belt-shaped film F is continuously conveyed toward the end seal portion 30, and the side edges f, f are heat-sealed by the vertical seal portion 20 to form a tubular portion T. It is withdrawn from the unit 30. When the article carrying-in section 40 is operated while continuing this operation, the articles M are fed from the open end D of the tubular section T onto the rolled strip film at a predetermined interval one by one, and are sequentially terminated as the strip film F advances. It moves toward the seal part 30. Immediately before the first article M reaches the end seal portion 30, the end seal portion 30 is operated, and the seal cutter 3 is moved.
1, 31 heat seals the tubular portion T in the transverse direction, and cuts the strip film along the center line of the heat seal width. As a result, a bag portion B containing one article M is formed in front of the end seal portion 30. Next, the seal cutters 31 and 31 are opened, the bag portion B containing the articles M is sent out onto the carry-out conveyor 32, and the seal cutters 3
1, 31 are operated to heat seal the rear end of the bag portion B on the carry-out conveyor 32, and cut the succeeding strip film F along the center line of the heat seal width. As a result, the individually separated articles M are placed on the unloading conveyor 32.
Is obtained, and a bag portion B containing the next article is formed at the tip of the subsequent tubular portion T. The obtained package P is carried out to the next step by operating the carry-out conveyor 32.

At the same time as the operation of the article carrying-in section 40 is started, an inert gas G, in this embodiment, nitrogen gas, is injected from the nozzle 50 into the cylindrical section T. In this embodiment, the supply gas pressure of the nitrogen gas is 2 kg / cm ² G, and the flow rate is 30 liter / min. At this time, the inert gas G injected into the cylindrical portion T
Is mainly replaced with the air in the space between the articles placed in the advancing tubular portion T. Therefore,
The space inside the package P, whose front and rear portions are sealed by the seal cutters 31, 31, is in a state where air is removed and the inert gas G is filled and sealed.

If the gas filling and packaging machine of the above embodiment is used,
As shown in FIG. 3, since the injection port 51 of the nozzle does not protrude into the conveying path of the article M, the tubular portion T can be formed in close contact with the outer periphery of the article M, and the article M and the packaging material can be in close contact. Thus, a tightly packed package is obtained, and the remaining small internal space of the closely packed package is replaced with an inert gas. In addition, since the inert gas is injected obliquely forward and inward from the seam S of the film into the space between the articles, the inert gas hits the article M in front and turns over, and passes through the bottom of the space. A circulation path is formed that is discharged from the gap between the side edges f, f with the internal air. This saves the use of inert gas and increases the rate of air displacement in the space. Under the conditions of the supply gas pressure and the supply gas flow rate of this embodiment, a desired level of the gas replacement rate of 95% or more can be achieved. At this gas replacement rate, the oxygen concentration in the package is 1% or less.

(Measurement Example) In the gas filling and packaging machine of the above-described embodiment, the gas replacement ratio was measured when the major axis of the nozzle injection port 51, the supply gas pressure, and the supply gas flow rate were variously changed. In these measurement examples, the minor diameter of the nozzle injection port 51 was fixed at 3 mm. Fig. 4 shows that the long diameter of the injection port is 18mm
, And the supply gas pressure was 1.0 kg / cm ² G, respectively.
The relationship between the supplied nitrogen gas flow rate and the nitrogen gas replacement rate when changing to 0 kg / cm ² G and 3.0 kg / cm ² G is shown. FIG. 5 shows the supply when the major diameter of the injection port was fixed at 10 mm and the supply gas pressure was changed to 1.0 kg / cm ² G, 2.0 kg / cm ² G, and 3.0 kg / cm ² G, respectively. The relationship between the nitrogen gas flow rate and the nitrogen gas replacement rate is shown.

In the measurement ranges of FIGS. 4 and 5, it can be seen that the larger the opening area of the nozzle injection port, the higher the gas replacement rate. Although both the supply gas pressure and the supply gas flow rate have an effect on the gas replacement rate, as a result of dispersion analysis based on the above data, it has been found that the supply gas flow rate has a large effect particularly at the contribution rate of 72%. As a result of further study of the opening area of the nozzle orifice, when the minor axis of the orifice is widened and when the major axis exceeds 1.5 times the width W of the seam S of the band-shaped film, the gas is scattered outside and wasted. The amount was found to be large. From this point of view, the nozzle orifice has a flat shape,
Its major axis is 0.5 times the width W of the band-shaped film joint S
It is preferable that the diameter is 1.5 times and the short diameter of the injection port is 1 mm to 3 mm. In order to reduce the amount of consumed gas, it is desired to suppress the supply gas pressure and the supply gas flow rate as much as possible. From this viewpoint, the necessary and sufficient supply gas pressure is 0.5 kg / cm ² G to 4 kg / cm. Within ² G,
It was confirmed that the supply gas flow rate was in the range of 10 liter / min to 40 liter / min.

Although the above embodiment relates to a horizontal type gas filling and packaging machine, the present invention is not limited to this, and may be a vertical type. Even in a packaging system formed more than that, the gas filling and packaging machine of the present invention can be applied by using at least one of them for gas replacement.

[0026]

According to the gas-filling and packaging machine of the present invention, the injection port of the nozzle for injecting the inert gas into the cylindrical portion is not inclined from the seam of the film side edge toward the obliquely inward in the traveling direction of the cylindrical portion. Since it is arranged to inject the active gas, the gas replacement by the inert gas is performed efficiently, and the amount of gas radiated without contributing to the gas replacement is reduced, thereby reducing the amount of the inert gas used. In addition, it is possible to manufacture a package whose inside is highly substituted with an inert gas.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention.

FIG. 2 is a perspective view showing a part of the embodiment.

FIG. 3 is a cross-sectional view showing a part of the embodiment.

FIG. 4 is a graph showing a relationship among a nitrogen gas supply pressure, a gas supply flow rate, and a gas replacement rate when the nozzle injection port has a major axis of 18 mm.

FIG. 5 is a graph showing a relationship among a gas supply pressure, a gas supply flow rate, and a gas replacement rate when a nozzle injection port has a major axis of 10 mm.

[Explanation of symbols]

 10: Film transport section 11: Guide roll 12: Rounding member 13: Lower conveyor 14: Upper conveyor 20: Vertical seal section 21: Nipping roll 22: Nipping roll 23: Heat sealer 30: End seal section 31: Seal cutter 32: Outgoing conveyor 40: Article loading section 41: Conveyance plate 42: Dispenser 43: Claw 50: Nozzle 51: Injection port F: Strip film f: Side edge part T: Cylindrical part B: Bag part S: Seam W: (Match) Width of eye S) D: Open end G: Inert gas M: Article P: Package

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuro Kamada 1-7-7 Honjo, Sumida-ku, Tokyo F-term in Lion Corporation (reference) 3E053 AA06 BA05 BA10 DA02 FA01 GA01 GA07 GA08 JA03

Claims (4)

[Claims] 1. A strip-shaped film for packaging is rolled in the width direction while running in the length direction, and the side edges on both sides of the film are aligned so that the inner surfaces of the film are in contact with each other. Sealing to form a tubular portion, forming a bag portion at the tip of the tubular portion by transversely sealing the tip of the formed tubular portion in the transverse direction, and from the open end side of the running tubular portion Packaging in which an article is intermittently introduced toward the bag section so that the bag section accommodates one unit of the article, and the rear end of the bag section in which the article is accommodated is laterally sealed to form a unit package. In the machine, having an inert gas injection nozzle for injecting an inert gas into the cylindrical portion to replace the air in the cylindrical portion and the bag portion with an inert gas, the nozzle of this nozzle, the injection port of the film Inert gas is injected from the joint at the side edge toward the inside of the cylindrical part in the direction of travel. Gas filling and packaging machine, characterized in that it is arranged to morphism. 2. The gas-filled package according to claim 1, wherein the strip-shaped film is caused to travel in a horizontal direction, and articles are introduced into the tubular portion from the open end of the tubular portion at predetermined intervals. Machine. 3. The width of the seam at the side edge of the film is 5 mm.
The nozzle has a flat injection port extending in the width direction of the seam, and the major axis of the injection port is 0.5 to 1.5 times the width of the seam. Within
The gas filling and packaging machine according to claim 1 or 2, wherein a short diameter of the injection port is in a range of 1 mm to 3 mm. 4. A feed gas pressure of the inert gas injected from the nozzle is in the range of ^{0.5kg / cm 2 G~4kg / cm 2} G, the feed gas flow rate of 5 l / min to 40 l / The gas-filled packaging machine according to any one of claims 1 to 3, which is within the range of minutes.