JP5036352B2 - Method and apparatus for vertically sealing packaging film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a beautiful vertical seal while preventing the effect of heat on an item packaged. <P>SOLUTION: The vertical sealing apparatus 20 includes: sandwiching rollers 26 that sandwich the overlapping portions of the end edges 12 of film 10 continuously conveyed in the direction of conveyance of the film 10; a film guide 32 that is oriented toward the film sandwiched part 12a held in the sandwiching rollers 26 and tautly guides the film so that the feed opposite angle &alpha; of the film end edges 12 is an acute angle; and a laser emitting means 44 for emitting near infrared laser beams to the internal face of the film in the film sandwiching part 12a. The vertical sealing apparatus 20 seals the film sandwiched part 12a by converging the near infrared laser beams into the film sandwiched part 12a by the reflection of the near infrared laser beams from the internal face of the film 10 held in the stretching guide part of the film guide 32. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a method and an apparatus for vertically sealing a packaging film in which film edge portions along the transport direction of a continuously transported film are overlapped and sealed.

  The horizontal bag making and filling machine includes a vertical sealing device for stacking and sealing film edge portions along the transfer direction of a cylindrically formed film. In this vertical sealing apparatus, for example, the film is welded and sealed by sandwiching and heating the film edge with a seal roller heated to about 150 ° C. to 200 ° C. by a heater. As described above, in the method of sealing the film by heating the seal roller, when the film feeding is temporarily stopped, the film sandwiched by the seal roller is excessively heated, so the film surface is melted and the seal is poor. There was a problem that occurred. In order to cope with this, a mechanism for temporarily separating the seal rollers from each other and releasing the holding of the film is provided in response to the stop of the film transfer. Further, in the case of a packaged item that is easily affected by heat, such as chocolate, the transport bed on which the packaged item is placed via a film is heated by the influence of heat generated from the sealing roller. Measures such as providing a cooling device to prevent heating of the transfer bed were taken. As described above, it is necessary to select a mechanism, a member, and the like for the vertical seal device and the surrounding structure in consideration of the heat effect from the seal roller, and there is a problem that the configuration becomes complicated. Also, the heating method using a heater has a large energy loss.

In addition, a vertical sealing device having a mechanism for sealing a film using a laser has been proposed instead of a method of sealing a film by heating a seal roller (see Patent Document 1). In the vertical sealing device of Patent Document 1, the film edge portions are overlapped on the projecting flat surface of the upper surface of the core provided in the bag making means for forming the film into a cylindrical shape, and the outer surface of the polymerized film edge portion is overlapped. On the other hand, a laser beam is irradiated by a carbon dioxide laser irradiation device, thereby providing a seal along the film transfer direction.
Japanese Patent No. 2550664

  The carbon dioxide laser irradiation device used in the vertical sealing device of Patent Document 1 irradiates the film with 10.6 μm laser light belonging to the far infrared wavelength range. Far-infrared laser light with a relatively long wavelength is difficult to transmit, so even if the film is transparent, the laser light is absorbed on the surface where the inner surface of the polymerization edge of the film should be welded. It will be heated and the outer surface of a superposition | polymerization edge part will be heated mainly. For this reason, when heated with far-infrared laser light to the extent that the sealant layer on the inner surface of the polymer edge can be welded, the outer surface of the film edge will be excessively melted, for example, a bead like a bead generated during metal welding There is a difficulty that part occurs. Therefore, the method of sealing the film edge with the far-infrared laser beam is inferior in appearance of the sealed portion after welding as compared with the method of sealing the film edge by heating the sealing roller with a heater. End up. For this reason, the method of sealing using far-infrared laser light has not been suitable for packaging foods or the like whose commercial value depends on the appearance of the packaging.

  That is, the present invention has been proposed in order to suitably solve these problems inherent in the vertical sealing method and apparatus for packaging films according to the prior art, and can be packaged with a simple configuration. It is an object of the present invention to provide a method and an apparatus for vertically sealing a packaging film capable of preventing the heat effect of the above and obtaining a good-looking seal part.

In order to overcome the above-mentioned problems and achieve the intended purpose, a method for longitudinally sealing a packaging film according to claim 1 of the present application,
A sandwiching roller provided between the first feed roller on the upstream side in the film transfer direction and the second feed roller on the downstream side, with the overlapping portion where the film edge portions along the transfer direction of the continuously transferred film overlap each other sandwiched by a longitudinal sealing method of sealing the film nipping portion,
The overlapping portion is guided to extend outward through a slit provided in a shielding member that does not transmit near-infrared laser light, and is extended so that the extending end side is widened. The film guide is stretched and held so that the opposing angle of the film edges becomes an acute angle ,
Through the stretch holding part of the overlapped portion that is expanded on the extending end side, the film inner surface of the film sandwiching portion is irradiated with near infrared laser light, and the inner surface reflection of the film at the edge of the film causes near infrared laser light to be irradiated. The film end edge is sandwiched and sealed with the sandwiching roller while the film is transported while being focused on the film sandwiching section.
According to this, near-infrared laser light can be focused on the film clamping part using the internal reflection at the edge of the film, there is little energy loss, and there is an adverse effect on the appearance of the package and the packaging. Therefore, a good seal portion can be obtained with a simple configuration. Further, the film clamping portion can be properly sealed without strictly irradiating the laser beam with respect to the film clamping portion. Furthermore, since the film is transported by the first feed roller and the second feed roller provided in the front and back of the film transport direction with the sandwiching roller interposed therebetween, when a film that is easily affected by elongation or the like due to film heating or the characteristics of the film itself is used. Even if it exists, while being able to obtain a favorable seal | sticker part, a laser beam will leak to the to-be-packaged goods side accidentally by the shielding member which guides a film edge part so that it may extend outside through a slit. Can be effectively prevented.

In order to overcome the above-mentioned problems and achieve the intended purpose, a vertical sealing device for a packaging film of the invention according to claim 2 of the present application,
A sandwiching roller that sandwiches the overlapped portion of the film edge portions along the transport direction of the continuously transported film; and
A first feed roller and a second feed roller installed on the upstream side and the downstream side in the film transport direction to sandwich the sandwiching roller and sandwiching and transporting the film edge portion;
A shielding member composed of a material that does not transmit near-infrared laser light and extending outward through a slit formed along the film transfer direction to guide the overlapping portion;
The overlapping portion transferred between the first feed roller and the sandwiching roller is expanded so that the extending end side of the film extending from the slit is widened, and directed toward the film sandwiching portion of the sandwiching roller. A film guide that stretches and guides the opposing edges of the film edge portions to an acute angle;
A laser irradiation means for irradiating a near-infrared laser beam to the inner surface of the film of the film sandwiching portion , through the stretch holding portion of the overlapping portion that is expanded on the extending end side ;
The near-infrared laser beam is focused on the film sandwiching portion by reflection of the inner surface of the film at the edge of the film to seal the film sandwiching portion.
According to this, the same effect as that of the first aspect can be obtained, and the assembly of the apparatus is simplified.

The gist of the invention according to claim 3 is that the sandwiching roller is disposed close to the second feed roller side.
According to this, the part welded by the pinching roller is immediately cooled by the second feed roller, and a high sealing property and a clean seal part can be obtained.

  According to the vertical sealing method of the packaging film according to the present invention, the near infrared laser beam is focused on the film sandwiching portion using the internal reflection of the film edge, thereby preventing the heat effect on the packaged object. A good-looking seal part can be obtained. Moreover, according to the vertical sealing device for a packaging film according to the present invention, the near-infrared laser beam is focused on the film sandwiching portion by utilizing the internal reflection of the film edge, so that it can be packaged with a simple configuration. It is possible to obtain a good-looking seal portion by preventing the heat effect of the.

  Next, a preferred embodiment of the method and apparatus for vertically sealing a packaging film according to the present invention will be described below with reference to the accompanying drawings. In this embodiment, the horizontal bag making and filling machine fills the film in the process of transporting the article to be packaged in the horizontal direction, and overlaps and seals the welding surfaces of the film edge portions along the film transport direction. A vertical seal device provided in the above will be described as an example.

As shown in FIG. 1, a vertical sealing device 20 according to the embodiment is provided downstream of the bag making means 16 for forming a film 10 drawn from a film supply source (not shown) in a cylindrical shape. The vertical sealing device 20 mainly includes a transport bed (shielding member) 22 for supporting an article to be packaged filled in a cylindrically formed film 10 from a supply conveyor (not shown ), and a cylindrically formed film 10. A pair of sandwiching rollers 26, 26 for sandwiching the polymer film edge portions 12, 12, a film guide 32 for guiding each film edge portion 12, and a pair of sandwiching rollers 26, 26 for the film edge portions 12, 12 And a laser irradiation means 44 for heating the inner surface of the film sandwiching portion 12a with near infrared laser light (see FIG. 2). Further, the vertical sealing device 20 includes a pair of first feed rollers 28 and 28 and a pair of second feed rollers 30 and 30 disposed in the front and rear of the film transport direction with the pair of sandwiching rollers 26 and 26 interposed therebetween, The film edge portions 12 and 12 where the film 10 is superposed are sandwiched and transported by the feed rollers 28 and 28 and the second feed rollers 30 and 30. In addition, the film 10 is subjected to a treatment capable of reflecting near-infrared laser light by making the whole or at least the film edge portions 12 and 12 a material that can reflect near-infrared laser light, or coloring or other materials. What was done is adopted. As such a film 10, for example, a laminate film obtained by laminating an easy-sealable synthetic resin film such as unstretched polypropylene and a metal foil such as an aluminum foil, or a deposited film obtained by vapor-depositing aluminum is preferable.

  As shown in FIG. 1 or 3, the transfer bed 22 extends horizontally downstream of the bag making means 16 in the film transfer direction on both sides of the slit 24 coinciding with the center of the film transfer line. The film edge portion 12 is a plate-like member made of a material capable of shielding the laser beam, and is polymerized in a palm-like manner so that the inner surfaces are in contact with each other under the package filled in the tubular film 10. , 12 are extended and guided downward from the slit 24 so that the lower surface of the package is supported via the film 10 when the film 10 is transferred.

  The pair of sandwiching rollers 26 and 26 sandwich the film edge portions 12 and 12 extending from the slit 24 under the transport bed 22 and are configured to be freely rotatable so that they can rotate as the film is transferred. . A pair of first feed rollers 28, 28 are disposed upstream of the sandwiching rollers 26, 26 in the film transport direction, and a pair of second feed rollers 30, 30 are located close to the downstream side of the sandwiching rollers 26, 26 in the film transport direction. Be placed. The first feed rollers 28 and 28 and the second feed rollers 30 and 30 are rotationally driven by driving means such as a motor (not shown) with the film edge portions 12 and 12 sandwiched therebetween, so that the tubular film 10 is It is transferred downstream in the film transfer direction. The clamping rollers 26, 26, the first feeding rollers 28, 28, and the second feeding rollers 30, 30 are all provided with an opening / closing mechanism that can release the clamping state of the film edge portions 12, 12. .

  The film guide 32 is V-shaped at each film edge 12 transferred to the film clamping part 12a by the clamping rollers 26, 26 between the clamping rollers 26, 26 and the first feed rollers 28, 28. It is arranged so that it can be extended and guided. The film guide 32 is positioned below the transport bed 22, is symmetrically disposed in the width direction across the slit 24, and a pair of guide portions 34 whose upper portions face the inside of the film edge portions 12 and 12. , 34, and adjusting means capable of adjusting the angle of each guide portion 34 with respect to the film transport direction and the distance between the guide portions 34, 34. In each guide portion 34, a support bar 34b extending below a support piece 34a having an upper portion formed in a plate shape is held by a slide block 40 so as to be rotatable and adjustable in height. In addition, the support piece 34a of each guide part 34 is bent and formed toward the other guide part 34 with which an upper end part opposes, as shown in FIG. The film guide 32 holds both guide portions 34 and 34 in contact with the inner surfaces of the corresponding film edge portions 12, respectively, and the film edge portion 12 faces the film holding portion 12a by the holding rollers 26 and 26. , 12 are arranged so as to be extended and guided in a V shape in which the mutual feed opposing angle α is an acute angle. Further, in this embodiment, the film edge portions 12, 12 that are superposed by the first feed rollers 28, 28 have their extended ends extending below the slit 24 at the guide portions 34, 34. Toward the film sandwiching portion 12a by the sandwiching rollers 26, 26, and is fed so as to become narrower (see FIG. 2).

  The slide block 40 extends in the width direction from the side wall 21 and is slidably arranged at a predetermined distance from a guide bar 42 provided so as to intersect the film transfer line. Accordingly, the distance between the guide portions 34 and 34 facing each other can be changed by bringing the slide blocks 40 and 40 closer to or away from each other. That is, the film guide 32 is adjusted by adjusting the angle of each guide portion 34 with respect to the film transport direction and the separation distance or height of both guide portions 34, 34, or a combination thereof. The twelve rollers 26, 26 are configured to change the feed opposing angle α.

  The laser irradiation means 44 includes an irradiation head 46 that irradiates near-infrared laser light excited by a laser transmitter (not shown) to the film inner surface of the film sandwiching portion 12a, and includes an irradiation head 46 and a laser light guiding fiber 48. The connected irradiation head 46 spot-irradiates near-infrared laser light obliquely upward through the widened portion of the film guides 12 and 12 extending below the transport bed 22 at the film guide 32. It is arranged at a position to obtain (see FIG. 1). In the present embodiment, the irradiation angle of the irradiation head 46 with respect to the film holding unit 12a is set to be inclined by, for example, about 30 degrees with respect to the horizontal plane serving as the film transfer line, and the irradiation head 46 has the film holding unit. For example, the laser beam is positioned so as to be irradiated with a spot diameter of about 2 mm with respect to 12a. Here, as the laser irradiation means 44, one capable of irradiating laser light in the near-infrared wavelength range having excellent reflectivity to the film 10 from far-infrared is used, for example, laser light in the wavelength range of about 800 nm to 1000 nm. It is preferable to use a semiconductor laser that can irradiate. In this embodiment, a semiconductor laser irradiation device having a trade name “LD heating device (model L10060)” manufactured by Hamamatsu Photonics Co., Ltd., having an optical output of 30 W and a wavelength of 940 nm is employed as the laser irradiation means 44.

  On the downstream side of the vertical sealing device 20, an end seal mechanism 50 having a pair of heating seal bodies 52, 52 facing each other up and down across the transfer path of the film 10 is disposed. Each package is obtained by transverse sealing before and after sandwiching and cutting.

  Next, the vertical sealing method of the film 10 using the vertical sealing apparatus 20 which concerns on an Example is demonstrated. The film 10 drawn from the film supply source is formed into a cylindrical shape by the bag making means 16, and the film edge portions 12, 12 are superposed in a palm shape and extend downward through the slit 24 of the transport bed 22. . The film edge portions 12 and 12 are sandwiched between the first feed rollers 28 and 28 and the second feed rollers 30 and 30, and the film 10 is transferred by the rotational force. Both film edge portions 12, 12 sandwiched between the first feed rollers 28, 28 and brought into a superposed state are transferred to the sandwich rollers 26, 26 disposed close to the upstream side of the second feed rollers 30, 30. In the meantime, each guide portion 34 in the film guide 32 on the upstream side of the sandwiching rollers 26 and 26 faces the film inner surface side in the film edge portions 12 and 12, and the film sandwiching portion 12 a in the sandwiching rollers 26 and 26. The film edge portions 12 and 12 that are transported toward the film are spread and guided in an expanded state. At this time, the film edge portions 12 and 12 are spread and guided in a C-shape in which the film extending edges extending downward from the slit 24 spread downward. Further, the feeding edge angle α of the film edge portions 12 and 12 toward the film sandwiching portion 12a by the sandwiching rollers 26 and 26 is stretched in a V shape having an acute angle.

  The laser irradiating means 44 is held in a state of being spaced apart and stretched in a V shape by the film guide 32 and is guided to the film clamping portion 12a through both film edge portions 12 and 12, and the film clamping portion. The near-infrared laser beam is irradiated from the irradiation head 46 to the inner surface of the film 12a. The continuously transported film 10 is heated by the laser beam until the film inner surface of the film sandwiching portion 12a reaches the film melting temperature, and then the film edge portions 12, 12 are transported while being sandwiched by the sandwiching rollers 26, 26. A tensile force is applied to the film edge portions 12 and 12 by the second feed rollers 30 and 30 on the side. As a result, the film edge portions 12 and 12 receive the clamping pressure of the clamping rollers 26 and 26, and the film inner surfaces are welded together to form a seal portion. Here, since the feeding opposing angle α of the film edge portions 12 and 12 toward the film sandwiching portion 12a in the sandwiching rollers 26 and 26 is set to an acute angle, the near infrared laser beam is transmitted to the film edge portions 12 and 12. The film can be focused on the film sandwiching portion 12a by internal reflection. The sealing portion of the film 10 can be clamped by a pair of second feed rollers 30 and 30 disposed in proximity to the pair of sandwiching rollers 26 and 26 to be cooled, thereby improving sealing performance and adjusting to an appropriate shape. it can.

  As described above, the laser light is directly irradiated on the inner surface of the film in the film sandwiching portion 12a, and the near-infrared laser light is focused on the inner surface of the film sandwiching portion 12a by utilizing the inner surface reflection of the facing film edge portions 12 and 12. Thus, the energy loss of the laser beam can be remarkably reduced, and the film edge portions 12 and 12 can be efficiently welded. Further, the film clamping portion 12a can be welded satisfactorily without setting the laser beam irradiation position accuracy with respect to the film clamping portion 12a, the assembly accuracy of the irradiation head 46, or the like. In addition, since the energy loss of the laser beam can be reduced, a laser irradiation means with a relatively low output of the laser beam can be employed.

  The vertical sealing device 20 stops the irradiation of the laser beam when the transfer of the film 10 is stopped, for example, when the operation of the packaging machine is stopped. Thereby, since the film clamping part 12a is not continuously heated, the film edge parts 12 and 12 are clamped when the transfer of the film 10 is stopped, as compared with a sealing method using a sealing means such as a sealing roller heated by a heater. A mechanism for separating the sealing means from the film 10 to be released becomes unnecessary, and the structure of the vertical sealing device 20 can be simplified.

(Experimental result)
In order to verify the relationship between reflection of near-infrared laser light between the inner surfaces of the film and heating at the film clamping portion in the present invention, as a near-infrared laser irradiation means as an experimental apparatus, the above-described semiconductor laser irradiation apparatus manufactured by Hamamatsu Photonics The same product was used. The laser irradiating means irradiates a laser beam at a position displaced from the film clamping part by the clamping roller by 5 mm as shown in FIG. 4 with the irradiation spot diameter on the line connecting the rotation centers of the clamping roller being 2 mm. The film transfer speed was set to 10 mm / sec and the film was pulled from the downstream side of the pinching roller. Two types of films were used: an aluminum foil laminate film (film A) sheet having a film thickness of 80 μm and an unstretched polypropylene aluminum vapor deposition film (film B) sheet having a film thickness of 75 μm. In the first experimental example shown in FIG. 4A, two films of the same kind are sandwiched between sandwiching rollers, and the feeding opposing angle to the sandwiching rollers is considered that the irradiated laser light can be reflected between the inner surfaces of the films. The conditions were set at an acute angle. On the other hand, in the second experimental example shown in FIG. 4B, the feeding facing angle is set larger than 90 °, and in the third experimental example shown in FIG. 4C, the feeding facing angle is set to the first experimental example. In addition, a stainless steel shielding plate having a thickness of 1.5 mm was disposed at a distance of 6 mm from the film sandwiching portion along the center of the film transfer line.

  In the experimental results, in the first experimental example, in both the film A and the film B, it was possible to weld the film pulled out by being sandwiched by the sandwiching roller despite being irradiated with the laser beam on one film inner surface. On the other hand, in the second experimental example and the third experimental example, in both the film A and the film B, the film drawn by being held by the holding roller was not welded despite being irradiated with the laser beam. From this, it was confirmed that the near-infrared laser beam was reflected from the inner surface of the film, and the reflected laser beam could be focused on the film sandwiching portion by setting the opposing angle of feeding the film to the sandwiching roller to an acute angle.

  Further, as a fourth experimental example, in order to verify the relationship between the reflectance of the film and the heating of the film clamping part (FIG. 4 (a)), two similar films are suitably welded under the conditions of the first experimental example. The output of laser light that can be obtained was obtained. The film was pulled from the downstream side of the sandwiching roller at a film transfer speed of 5 m / min. According to the fourth experimental example, the film A had two films suitably welded at an output of 14 W, whereas the film B required an output of 20 W in order to suitably weld the two films. . From these experimental results, it was verified that the film A is a film having a higher reflectance of near-infrared laser light because the film A can be welded at a lower laser output than the film B.

(Example of change)
The present application is not limited to the configuration of the above-described embodiment, and other configurations can be appropriately employed.
(1) The laser irradiation means 44 may employ a YAG (Yttrium Aluminum Garnet) laser or glass laser that can irradiate a laser beam having a wavelength of 1060 nm as long as it can irradiate a laser beam in the near infrared wavelength range. Can be considered. Since the YAG laser and the glass laser can be transmitted from the laser transmitter to the irradiation head 46 by the light guiding fiber 48 in addition to the semiconductor laser of the embodiment, the irradiation head 46 is close to the film sandwiching portion 12a serving as a seal position in the film 10. Can be arranged.
(2) When using a film that is less affected by heat such as elongation due to heating, the first feed rollers 28 and 28 or the second feed rollers 30 and 30 are driven to rotate in place of the freely rotating pinching rollers as in the embodiment. The film inner surface of the film clamping portion by the roller to be used may be irradiated with laser light. In addition, when sealing with the 1st feed rollers 28 and 28, you may abbreviate | omit either one or both of the pinching rollers 26 and 26 or the 2nd feed rollers 30 and 30 as needed.
(3) In the examples, the vertical sealing device of the horizontal bag making and filling machine is illustrated, but the vertical sealing method and the vertical sealing device of the packaging film according to the present invention are films that are polymerized on the side or above in which the film is folded in half. The present invention can be applied to various types of film sealing machines and methods for sealing edge edges, or for sealing film edges where two separate films are stacked vertically and horizontally. In any case, it is a matter of course that the facing surface where the film is superposed is a welding surface.
(4) The sandwiching rollers 26 and 26 may be disposed at an appropriate position between the first feed rollers 28 and 28 and the second feed rollers 30 and 30 as required, such as the film material.
(5) In the embodiment, the laser beam is irradiated from the obliquely lower side to the film sandwiching portion 12a. However, it is most preferable to irradiate the laser beam from the direction along the film transfer direction. By irradiating the film clamping part 12a with laser light from the horizontal direction that is the film transfer direction or from the direction close to the horizontal direction, the reflection efficiency between the polymer film edge parts 12 and 12 is increased, and the energy loss of the laser light is increased. This is because it can be minimized.

1 is a side view showing a vertical sealing device according to a preferred embodiment of the present invention. It is a top view which shows the vertical seal | sticker apparatus of an Example. It is the sectional view on the AA line of FIG. It is explanatory drawing about experiment.

Explanation of symbols

10 film, 12 film edge part, 12a film clamping part, 16 bag making means,
22 transfer bed (shielding member) , 24 slits, 26 clamping rollers,
28 First feed roller, 30 Second feed roller, 32 Film guide,
44 Laser irradiation means, 46 Irradiation head, α Feeding opposite angle

Claims (3)

A superposed portion where the film edge portions (12, 12) along the transfer direction of the continuously transferred film (10) are overlapped with each other is connected to the first feed roller (28, 28) on the upstream side in the film transfer direction and the downstream side. a longitudinal sealing method of sealing provided with the film nipping portion is clamped by clamping rollers (26, 26) and (12a) between the second feed roller (30, 30),
The overlapping portion is extended and guided outward through a slit (24) provided in a shielding member (22) that does not transmit near-infrared laser light, and the extended end side is expanded, and the film clamping portions stretched and held by the film edges towards the (12a) of each other (12, 12) feed the counter angle (alpha) is an acute angle so that the film guide (32),
Through the stretch holding portion of the overlapped portion that is expanded on the extended end side, the film inner surface of the film sandwiching portion (12a) is irradiated with near infrared laser light, and the film at the film edge portion (12, 12) ( 10) The near-infrared laser beam is focused on the film clamping part (12a) by the internal reflection of 10) and the film (10) is transported, while the film edge part (12, 12) is clamped by the clamping roller (26, 26). A method for longitudinally sealing a packaging film, wherein the packaging film is sealed. A sandwiching roller (26, 26) that sandwiches the overlapped portion where the film edge portions (12, 12) along the transport direction of the continuously transported film (10) are overlapped ;
The first feed rollers (28, 28) and the first feed rollers (28, 28), which are installed on the upstream and downstream sides of the film transport direction across the sandwiching rollers (26, 26) and transport the film by sandwiching and transporting the film edge portions (12, 12). 2 feed rollers (30, 30),
A shielding member (22) composed of a material that does not transmit near-infrared laser light, and extending and guiding the overlapping portion outward through a slit (24) formed along the film transfer direction;
The extending end side of the film (10) extending from the slit (24) widens the overlapping portion transferred between the first feeding roller (28, 28) and the sandwiching roller (26, 26). And widening and guiding the mutual feeding facing angle (α) of the film edge portions (12, 12) toward the film clamping portion (12a) of the clamping rollers (26, 26) at an acute angle. A film guide (32),
A laser irradiation means (44) for irradiating the film inner surface of the film sandwiching portion (12a) with a near-infrared laser beam through the stretched and held portion of the overlapped portion that is expanded on the extending end side ;
The near-infrared laser beam is configured to be focused on the film sandwiching portion (12a) by internal reflection of the film (10) at the film edge portions (12, 12) to seal the film sandwiching portion (12a). A vertical sealing device for a packaging film. The packaging film longitudinal sealing device according to claim 2, wherein the sandwiching rollers (26, 26) are arranged close to the second feed roller (30, 30) side .

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