JP2012111147A - Folding line forming device for packaging films - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form firm folding lines at a desired position regardless of the material and the strength of stiffness of a film.SOLUTION: A folding line forming device for packing films includes a fifth and sixth folding line forming rollers 81, 82 arranged face to face holding a strip film 21 in between. A sixth ridge 82a projecting to outside in an axial direction is provided on the peripheral surface in the peripheral direction of the sixth folding line forming roller, and a sixth recessed groove 82b is formed on both axial direction sides of the sixth ridge. A fifth recessed groove 81b is formed on the peripheral surface in the peripheral direction of the fifth folding line forming roller at a position facing the sixth ridge, and a fifth ridge 81a is formed at a position facing the sixth recessed groove. The strip film is held between the sixth ridge and the fifth recessed groove to form mountain-folding lines 21k on the strip film, and the strip film is held between the fifth ridge and the sixth recessed groove to form valley-folding lines 21j along the folding lines.

Description

  The present invention relates to a fold line forming apparatus for a packaging film, and more specifically to a technique suitable for forming a fold line at an appropriate position of a packaging film in the course of transporting a belt-like film.

  As is well known, a pillow packaging machine continuously feeds a belt-shaped film wound up on a roll of raw material to a bag making machine, and is made into a cylindrical shape when passing through the bag making machine. . And a cylindrical film is formed by sealing the film superposition | polymerization end which was bag-formed and overlapped cylindrically through the bag making machine with the center seal apparatus arrange | positioned in the downstream of a bag making machine. In addition, a product transport / supply device is arranged on the upstream side of the bag making device, and products transported from the product transport / supply device at predetermined intervals are supplied into the bag making device. As a result, when the product passes through the bag making machine, the product is stored in the cylindrical film at predetermined intervals, and the product is conveyed together with the cylindrical film. Then, a pillow packaging body that encloses the product is manufactured by sealing and cutting the tubular film so as to cross the lateral direction at predetermined intervals in an end seal device arranged on the carry-out side of the pillow packaging machine. The

  Usually, the outer shape of the pillow package is caused by the outer shape of the product to be stored. In other words, when the product is box-shaped, the package is also formed into a box-like shape. However, when a plurality of small articles such as bags and sachets are stored or in the case of a kneaded product, it remains cylindrical. It becomes. Moreover, even if the shape of the product is rectangular, in the case of a soft product such as castella, the outer shape of the package is substantially rectangular, but the corners are rounded.

  Therefore, in this type of pillow packaging bag, as a part of increasing the commercial value, as shown in FIG. 1 (a), as shown in FIG. ) In which a mountain fold line 2 is formed. Moreover, in the example of FIG. 1, the valley fold line 3 is further formed in the center of the side surface, and it is made to fold inside. An apparatus for forming a fold line in a film used for manufacturing this type of package is disclosed in, for example, Patent Document 1.

  Moreover, FIG.1 (b) has shown another packaging form. This packaging form includes what is called a hem seal part 5 formed by folding a part of the packaging film 4 so as to overlap and sealing the overlapped part. The hem seal portion 5 of the packaging film 4 has an effect of increasing rigidity and maintaining a square cross section because the film portion is folded and sealed. The packaging bag 6 with a hem seal is less likely to lose its shape, and the product value can be increased. Also in the package 6 with a hem seal, a valley fold line 7 is formed at the center of the side surface and is folded inside.

  As shown in FIG. 1 (c), an apparatus for forming this type of fold line generally includes a pair of rollers 9, 9 'for sandwiching the belt-like film 8 from both sides, and the pair of rollers 9, 9' A fold line is formed by sandwiching the belt-like film 8 with a predetermined pressure between the ridges 9a and the concave grooves 9'a provided at opposite positions on the circumferential surface in the circumferential direction.

JP 2001-301707 A

  However, in the conventional method of forming a single fold line by sandwiching between the protrusion 9a and the concave groove 9'a, for example, a paper film or a stiff film is easily creased. However, resin (plastic) films, particularly those with no waist, have a problem that they are not easily creased.

  In order to solve the above-described problems, a folding line forming apparatus for a packaging film according to the present invention is (1) a packaging film that is provided in the middle of transporting a belt-like film in a packaging machine and forms a folding line at a predetermined position of the belt-like film. A fold line forming apparatus, comprising a pair of fold line forming rollers arranged opposite to each other with the belt-like film interposed therebetween, and projecting radially outward on a circumferential surface of one of the fold line forming rollers And a groove A is formed on both sides in the axial direction of the protrusion A, and the other circumferential surface of the fold line forming roller is recessed in a portion facing the protrusion A. In addition to providing the groove B, the protrusion B is provided in a portion facing the groove A, and the band film is sandwiched between the protrusion A and the groove B to form a fold line in the band film, Front with ridge B and groove A And to form an auxiliary folding line folded in the opposite direction with its fold line along its fold line by sandwiching the filmstrip.

  This fold line forming apparatus for packaging film corresponds to the fold line forming portion 43 of the embodiment. One fold line forming roller corresponds to the sixth fold line forming roller 82 of the embodiment, the protrusion A corresponds to the sixth protrusion 82a, and the groove A corresponds to the groove 82b. The other fold line forming roller corresponds to the fifth fold line forming roller 81 of the embodiment, the ridge B corresponds to the fifth ridge 81a, and the concave groove B corresponds to the concave groove 82b. According to this invention, the film part of the strip | belt-shaped film corresponding to the part finally bent in a package body is pinched | interposed with the protrusion A and the ditch | groove B, and the bending line of a predetermined direction is formed. At the same time, an auxiliary fold line that is folded in the opposite direction to the fold line is formed by sandwiching the belt-like film between the ridge B and the groove A. Therefore, reverse auxiliary fold lines may be formed on both sides of the fold line, and the band-like film is firmly brazed by the auxiliary fold line, so that the fold line to be originally formed is emphasized and folded firmly. be able to. When the folding direction of the fold line is directed to the inner surface side of the package, valley folding is performed, and when the folding line is directed to the outer surface side, mountain folding is performed. The former is used when forming at an intermediate point on the side surface of the package, and is described in detail in the embodiment. The latter is used when forming in the corner | angular part etc. of a package.

  (2) The height of the protrusion A from the circumferential surface of the one folding line forming roller may be longer than the depth of the concave groove A from the circumferential surface. The height of the protrusion A corresponds to the height a in the embodiment, and the depth of the concave groove A corresponds to the height b in the embodiment.

  (3) It is preferable that at least one of the pair of fold line forming rollers is provided with a heating unit so that the belt-shaped film sandwiched between the pair of fold line forming rollers is heated. In the embodiment, the heating means is realized by a heater built in the roller. Folding is performed with a fold line forming roller where the belt-like film has been softened by heat, and then the belt-like film is cooled to maintain the fold line, thereby forming the fold line more reliably and firmly. be able to.

  In the present invention, a fold line can be firmly formed at a desired position regardless of the material of the film and the strength of the waist.

It is a figure explaining a prior art example. It is a figure which shows suitable one Embodiment of the horizontal pillow packaging machine with which the folding line forming apparatus for packaging films was integrated. It is a figure which shows the film supply apparatus provided with the hem seal apparatus. It is a top view which shows schematic structure of a hem seal apparatus. It is a figure showing one suitable embodiment of a hem seal device. It is a figure explaining the structure of the 1st hem seal formation part, and its effect | action. It is a figure which expands and shows the X section in FIG. It is a figure explaining the structure and its effect | action of a 2nd hem seal formation part. It is a figure explaining the structure of a fold line formation part, and its effect | action. It is a figure which expands and shows the Y section in FIG. It is a figure which shows the state which was bag-shaped by the bag making machine. It is a figure which shows another example.

  FIG. 2 shows an example of a horizontal pillow packaging machine in which an embodiment of the folding line forming apparatus for packaging film of the present invention is mounted. This horizontal pillow packaging machine is for producing a package with a hem seal portion as shown in FIG. 1B, and FIG. 3 shows an example of a film supply apparatus in which the hem seal device is incorporated. . The folding line forming device is incorporated in a part of the hem seal device.

  First, the horizontal pillow wrapping machine 10 of this embodiment is arranged from the upstream side in the order of the product transport and supply device 11 and the wrapping machine main body 12, and further includes a film supply device 13 above them.

  The product conveyance supply device 11 is formed of a finger conveyor device that conveys the product 14 at regular intervals and sequentially supplies the product 14 to the packaging machine body 12 at the next stage. That is, the push finger 17 is attached to the endless chain 16 spanned between the front and rear sprockets 15 (only the front is drawn in the drawing). Then, by supplying the product 14 between the front and rear push fingers 17, the product 14 is conveyed at the finger pitch of the push fingers 17.

  The film supply device 13 is for continuously supplying the belt-like film 21 serving as a packaging film (wrapping material) for wrapping the product 14 to the packaging machine body 12. The film supply device 13 includes two original fabric rolls 20 obtained by winding the belt-like film 21 into a roll shape. One of the two original fabric rolls 20 actually supplies the band-shaped film 21 to the packaging machine body 12, and the other original fabric roll 20 is used as a spare. That is, when all of the belt-like film 21 is pulled out from the currently supplied roll 20, a spare original is provided at the rear end of the belt-like film 21 drawn out by the film connecting device (splicer) 38 shown in FIG. The head of the strip-shaped film 21 pulled out from the anti-roll 20 is connected so that the strip-shaped film 21 can be continuously supplied to the packaging machine body 12.

  The film supply device 13 conveys the belt-like film 21 continuously drawn out from the original fabric roll 20 through a predetermined conveyance path, and introduces a roller 22 (represented as a representative 1 in FIG. Only one is drawn). Further, the film supply device 13 incorporates a hem seal device 40 that forms a hem seal portion at a predetermined position of the belt-like film 21 as will be described later. That is, the film supply apparatus 13 of this embodiment conveys the flat sheet-like strip | belt-shaped film 21, forms a hem seal part in the middle of the conveyance, and supplies the strip | belt-shaped film with a hem seal part to the packaging machine main body 12. FIG.

  The belt-like film 21 has one surface (inner peripheral surface in the packaging body 34) melted by heating and becomes a sealant surface where the contact portions of the same surface are heat-sealed, and the other surface (outer surface in the packaging body 34). Becomes a non-seal surface which does not melt even when heated.

  The packaging machine body 12 includes a bag making device 24 on the carry-in side, and makes the bag into a cylindrical shape by passing the belt-like film 21 supplied from the film supply device 13 through the bag making device 24. Further, the products 14 sequentially carried out from the product conveyance supply device 11 are supplied to the bag making device 24.

  Further, the packaging machine main body 12 sandwiches a portion where both side edges 21 ′ of the belt-like film 21 that passes through the bag making device 24 and is formed into a cylindrical shape are overlapped on the downstream side of the bag making device 24, thereby increasing the conveyance force. A pinch roller 29 to be provided, a center seal device 27 that seals the overlapped portion, and a lower belt 26 that constitutes a conveyance path of the tubular film 25 that encloses the product 14 are provided in that order. Further, an upper restraining belt 28 is disposed at a predetermined position above the lower belt 26, and an end seal device 30 is disposed in front of the traveling direction thereof. The upper restraining belt 28 is disposed on the front side of the end seal device 30 and restrains the product 14 from floating upward. Thereby, the predetermined position (portion where the product 14 does not exist) of the tubular film 25 is correctly sealed and cut by the end seal device 30, and the product 14 is prevented from being bitten.

  The end seal device 30 includes a pair of top sealers 31 and 32 arranged to face each other in the vertical direction. The upper top sealer 31 has a lower surface as a seal surface 31a, and the lower top sealer 32 has an upper surface as a seal surface 32a. Further, a cutter blade is incorporated below the upper top sealer 31. The top sealers 31 and 32 move in a substantially rectangular locus by moving toward and away from each other and moving back and forth while maintaining the state where the seal surfaces 31a and 32a face each other. Then, the top sealers 31 and 32 move closer to each other, the seal surfaces 31a and 32a are sandwiched from above and below the desired portion of the tubular film 25 (between the front and rear products 14) and heat-sealed, and are tubular with a cutter blade. The film 25 is cut in the lateral direction. Thereby, the front-end | tip part (part which encloses the top product 14) of the cylindrical film 25 is isolate | separated, and the package 34 is manufactured. Then, the package 34 is conveyed on the carry-out conveyor device 35.

  Since the basic configuration of these horizontal pillow packaging machines 10 is the same as the conventional one, a detailed description thereof will be omitted. Of course, the horizontal pillow wrapping machine to which the present invention is applied can use various configurations other than this, and a reverse pillow in which a belt-like film is supplied from the lower side and the center seal portion is disposed above the conveyance path. Of course, a packaging machine is also good. The end seal device is not limited to the box motion type, and can be applied to various types such as a type that moves up and down (does not move back and forth) on the spot and a rotary type.

  As a schematic diagram in FIG. 2, a specific configuration of the film supply device 13 showing two raw rolls 20, one roller 22, and a hem seal device 40 is as shown in FIG. 3. That is, in the film supply device 13, two rotation support shafts 36 are rotatably mounted in parallel in a cantilevered state at a predetermined position above the standing machine frame. The original roll 20 is attached to each of the rotation support shafts 36, and the rotation support shaft 36 and the original roll 20 rotate together.

  The belt-like film 21 drawn out from each raw fabric roll 20 is guided to a splicer 38, and the belt-like film 21 drawn out from one of the raw fabric rolls 20 in use passes through the splicer 38 and has a plurality of rollers. 22 is carried by a desired conveyance path. The roller 22 includes a driving roller that drives the belt-shaped film 21, a tension roller that applies tension, a free roller that changes the conveyance direction of the belt-shaped film 21, and the like.

  Further, the leading end of the strip-shaped film 21 drawn out from the other spare original fabric roll 20 is guided to the position of the splicer 38 and stands by. And when the splicer 38 is used up, the front end of the roll roll wound around the new roll roll at the rear end of the belt-shaped film fed out from the roll roll. Are automatically joined.

  A hem seal device 40 is disposed downstream of the splicer 38. The hem seal device 40 forms fold lines at predetermined positions (positions corresponding to the four corners when formed into a cylindrical shape by a bag making machine) in the middle of the conveyance of the flat sheet-like belt-like film 21 in the conveyance direction. Then, the hem seal portion is formed by folding the predetermined position of the belt-like film 21 using the fold line thus formed and sealing the overlapped portion, and the hem seal portion is made to follow the film surface of the belt-like film 21 at the time of sealing. To.

  Then, in the present embodiment, the four hem seal portions are formed in two portions by two as shown in FIG. Here, in the first hem seal forming portion 41, the two hem seal portions 45 outside the belt-like film 21 are formed, and in the second hem seal forming portion 42 arranged on the downstream side of the first hem seal forming portion 41, Two inner hem seal portions 46 are formed. Furthermore, in the present embodiment, a fold line forming portion 43 is disposed downstream of the second hem seal forming portion 42, and a fold line 47 is formed at an intermediate point between the outer hem seal portion 45 and the inner hem seal portion 46. ing. As will be described later, the hem seal portions 45 and 46 are positioned at the four corners of the packaging body 34, and the folding lines 47 are formed in the middle of the side surfaces of the packaging body 34 so that the side surfaces are folded inwardly. Used. The fold line 47 is formed by an apparatus according to an embodiment of the fold line forming apparatus of the present invention.

  Thus, in this embodiment, since the 1st hem seal formation part 41 and the 2nd hem seal formation part 42 were formed in order along the conveyance direction of the strip | belt-shaped film 21, two hem seal parts were formed, respectively. The meandering of the film 21 can be suppressed. That is, since the hem seal portions 45 and 46 are formed by folding a predetermined film portion of the belt-like film 21, the width of the hem seal portions 45 and 46 is increased. Therefore, if the hem seal portions 45 and 46 are formed simultaneously at four locations, the hem seal portions 45 and 46 after the formation of the hem seal portions 45 and 46 are compared with the film width of the flat sheet-like strip film 21 before the hem seal portions 45 and 46 are formed. Since the film width is significantly shortened and the width of the film is reduced at a stretch, the urging force in the direction perpendicular to the conveying direction is applied to the band-shaped film 21 and the band-shaped film 21 may meander. In contrast, in the present embodiment, by forming the hem seal portion in two steps, one hem seal formation portion forms two hem seal portions, and the amount of reduction in the film width of the strip-shaped film 21 is reduced. Can be halved. Therefore, it can suppress as much as possible that the strip | belt-shaped film 21 meanders. As will be described later, in this embodiment, the protruding amount of the hem seal portions 45 and 46 can be reduced. Therefore, it is also possible to form hem seal portions simultaneously at four locations by appropriately setting the protrusion amount.

  The first hem seal forming part 41 forms a first fold line forming heating part 51 that heats the film while forming two fold lines respectively in the formation region of the two outer hem seal parts 45, and its first fold line forming. And a first press unit 52 that pressurizes the film portion folded so as to be folded along the folding line formed by the heating unit 51.

  As shown in FIG. 5 and FIG. 6B, the first fold line forming heating unit 51 includes a large-diameter disk-shaped first fold line-forming roller 61 disposed opposite to the band-shaped film 21, and a small-diameter disk-like shape. The two pairs of the second folding line forming rollers 62 are provided. The first folding line forming roller 61 is attached to a rotating shaft 63 with a built-in heater supported by a machine frame. The rotating shaft 63 is disposed so as to extend in a direction orthogonal to the transport direction of the strip film 21. The rotary shaft 63 is connected to a drive motor (not shown) and rotates in accordance with the conveyance speed of the belt-like film 21. Further, each first folding line forming roller 61 is movable independently in the axial direction of the rotating shaft 63. Then, by tightening the fixing screw at a desired position, the first fold line forming roller 61 is fixed to the rotating shaft 63 and rotates integrally. The rotating shaft 63 and the first folding line forming roller 61 are formed of a material having good thermal conductivity such as stainless steel or other metal, and the heat of the heater built in the rotating shaft 63 is applied to the first folding line forming roller. 61, the belt-like film 21 can be heated.

  The second fold line forming roller 62 is rotatably attached to the bearing plate 64. The bearing plate 64 is attached to the base base 65, and a slider (not shown) connected to the base base 65 coincides with a guide rail installed in parallel with the rotary shaft 63, and reciprocates along the guide rail. It is supposed to move. Therefore, when the slider (base stand 65) is moved, the bearing plate 64 and thus the second fold line forming roller 62 move laterally with respect to the belt-like film 21. That is, by this movement, the distance from the side edge of the position where the second folding line forming roller 62 contacts the belt-like film 21 to the center can be adjusted.

  Furthermore, the base 65 is urged toward the first fold line forming roller 61 by an urging means such as a spring. Thus, the second fold line forming roller 62 is urged toward the first fold line forming roller 61 with a predetermined pressure.

  As a result, the first and second fold line forming rollers 61 and 62 are moved to appropriate positions, the fold line forming rollers 61 and 62 come into contact with each other, and an arbitrary position of the belt-like film 21 is sandwiched with a predetermined pressure. The film part can be heated. The second fold line forming roller 62 is in a free state, and receives the rotational force of the first fold line forming roller 61 that rotates as the rotary shaft 63 rotates (during the operation, the belt-like film 21 is removed). Via).

  As shown in FIGS. 6B and 7, the first fold line forming roller 61 has a circumferential shape in the circumferential direction, that is, a surface facing the belt-like film 21, and a mountain shape on the radially outer side (the other side). The 1st protrusion 61a which protrudes in is provided. Similarly, the second fold line forming roller 62 has a second ridge 62a protruding in a mountain shape on the outer side in the radial direction (the other side) on the circumferential surface in the circumferential direction, that is, the surface facing the belt-like film 21. Provided. Each of the first and second protrusions 61a and 62a has a shape in which a substantially triangular mountain shape shown in the drawing is continuously rounded in the circumferential direction. Further, the outer shape is asymmetric, and the opposing surface sides of both protrusions 61a and 62a are steep. And the 1st protrusion 61a is set so that it may be located in the side edge side (the axial direction outer side of the rotating shaft 63) of the strip | belt-shaped film 21. FIG.

  As shown in FIG. 6A, the flat belt-like film 21 passes between the first fold line forming roller 61 and the second fold line forming roller 62 as shown in FIGS. As a result, the rollers 61 and 62 are sandwiched. At this time, the belt-like film 21 is sandwiched and bent between the first ridge 61a and the second ridge 62a. More specifically, a fold line is formed at a portion that is energized by each of the vertices 61a 'and 62a' and contacts the vertices 61a 'and 62a'. That is, two fold lines of a valley fold line 21a and a mountain fold line 21b (referenced to the second fold line forming roller 62 side) are formed in this order from the side edge side of the belt-like film 21.

  Further, in the present embodiment, the first concave groove is formed on the peripheral surface of the first fold line forming roller 61 in the vicinity of the portion facing the apex 62a ′ of the second ridge 62a, that is, the ridge of the first ridge 61a. 61b is formed. The first concave groove 61 b is formed continuously in the circumferential direction of the first fold line forming roller 61. Then, the apex 62a ′ of the second protrusion 62a enters the first concave groove 61b. When the inner shape (cross section) of the first concave groove 61b and the outer shape (cross section) of the apex 62a 'portion of the second protrusion 62a are substantially matched and matched, the apex 62a' of the second protrusion 62a is set. The film fold line 21b is firmly formed in the film portion folded in step (b).

  Similarly, on the peripheral surface of the second fold line forming roller 62, a second groove 62b is formed adjacent to the apex 61a 'of the first ridge 61a, that is, near the ridge of the second ridge 62a. Has been. The second concave groove 62 b is formed continuously in the circumferential direction of the second fold line forming roller 62. Then, the vertex 61a ′ of the first protrusion 61a enters the second concave groove 62b. When the inner shape (cross section) of the second concave groove 62b and the outer shape (cross section) of the apex 61a 'portion of the first protrusion 61a are substantially matched and matched, the apex 61a' of the first protrusion 61a is set. The valley fold line 21a is firmly formed in the film part folded in. Furthermore, a flat portion 62c is formed in an area outside the second concave groove 62b on the peripheral surface of the second fold line forming roller 62, and a film portion facing the flat portion 62c is flat before passing. As shown in FIG. 7, the flat portion 62 c may be connected to the conveyance height position of the belt-like film 21 a and the side edges of the belt-like film 21 may be sandwiched from both sides of the film. It does not come into contact (if the film part is parallel to the entire belt-like film 21, it will come into contact with the flat part 26c as shown by the broken line). Thus, when it is made non-contact, the possibility that the strip-shaped film 21 will be in a keloid state can be suppressed as much as possible.

  Thereby, although the valley fold line 21a is firmly formed in the second concave groove 62b, the film portion outside the valley fold line 21a of the belt-like film 21 is guided by the flat portion 62c and extends straight as it is. Therefore, two pairs of the valley fold line 21a and the mountain fold line 21b are formed by passing through the pair of the first fold line forming roller 61 and the second fold line forming roller 62.

  Further, the height h of the first protrusion 61a and the height h ′ of the second protrusion 62a are substantially matched with the width (protrusion length) of the hem seal portion. Strictly speaking, the width of the hem seal part is shorter than the width of the hem seal part because of the length of the opposite hypotenuses of both protrusions 61a and 62a. By adopting the above configuration, as shown in FIG. 6 (c), the band-shaped film 21 passes through the first fold line formation heating unit 51, and thus, on both side edges, the valley fold line 21a and the mountain fold line respectively. Two pairs of 21b are firmly formed. And the space | interval of the valley fold line 21a and the mountain fold line 21b which comprises a pair becomes the height h (= height h 'of the 2nd protrusion 62a) + (alpha) of said 1st protrusion 61a.

  As described above, the valley fold line 21a and the mountain fold line 21b are firmly formed sequentially in this order from the outside of the belt-like film 21, so that the first fold line forming heating unit 51 (first and second fold line formation) is formed. As shown in FIG. 6C, the film portion that has passed the rollers 61, 62) is bent and deformed so that the portion of the mountain fold line 21b falls outward (the valley fold line 21a is folded inward). Become.

  Further, the belt-like film 21 is heated by the first fold line forming roller 61. As described above, the belt-like film 21 is a sealant surface that can be heat sealed on one surface, but is set so that the sealant surface faces the first folding line forming roller 61 side. Furthermore, the flat part 61c is formed in the area | region outside the 1st ditch | groove 61b of the surrounding surface of the 1st folding line formation roller 61, and the strip | belt-shaped film 21 comes into contact with the flat part 61c.

  Of the sealant surface of the belt-like film 21 on the first fold line forming roller 61 side, the film portion adjacent to the peripheral surface of the first fold line forming roller 61 is heated and melted. In particular, the steep surface of the first protrusion 61a and the film portion facing the first concave groove 61b and the flat portion 61c are firmly heated. And as above-mentioned, since the strip | belt-shaped film 21 after passing the 1st fold line formation heating part 51 falls in the part of the mountain fold line 21b outside (because the valley fold line 21a is folded inward), The film part 21c sandwiched between the valley fold line 21a and the mountain fold line 21b folds over the film part 21d outside the valley fold line 21a of the belt-like film 21. That is, when the film part 21c falls inward, the melted sealant surface comes into contact with the film part 21d.

  The 1st press part 52 is provided with a pair of press rollers 52a and 52b arrange | positioned on both sides of the strip | belt-shaped film 21. As shown in FIG. Although not shown, the pair of press rollers 52a and 52b is attached to a rotary shaft that is rotatably supported by a machine frame or the like of a horizontal pillow packaging machine, and can be configured to rotate integrally. The press rollers 52a and 52b have a flat circumferential surface and pressurize the region including the folded film portions 21c and 21d. Thereby, the sealant surface of the film portion 21c in the heated and melted state is pressed against the film portion 21d and is also cooled and firmly heat-sealed. As a result, the two outer hem seal portions 45 are formed. The width of the hem seal portion 45 (the amount of outward protrusion) can be suppressed to about 2 mm or less, for example. If the protrusion amount is 2 mm, the film is folded so that a film width of 4 mm is required in one hem seal portion, and if the hem seal portions are provided at the four corners, the film width is increased by 16 mm in total. This requires less film consumption than the conventional one (the hem seal portion has a protrusion amount of 5 mm and requires 40 mm as a whole).

  Note that the film portion 21d 'that has been in contact with the flat portion 61c of the first fold line forming roller 61 also has a melted sealant surface, and the film portions 21c and 21d' also fold over as the film portion 21c falls. The film portions 21c and 21d 'are also pressed by the press rollers 52a and 52b, but are not heat sealed because the non-sealing surfaces are in contact.

  In the present embodiment, since the first fold line forming roller 61 side is the sealant surface of the belt-like film 21, the sealant surface is directly heated by the roller 61 and melted firmly, but the film portion 21d is not directly heated. Therefore, the contact surfaces of the folded film portions 21c and 21d are in a state where only one film portion 21c is melted. In the case of a hem seal, unlike an end seal or a center seal that closes the package, seal strength up to the end seal or the like is not required, so there is no problem even if the seal is in a melted state on only one side. Further, since the second fold line forming roller 62 side is used as a sealant surface, the contact surfaces of the film portions 21c and 21d 'accompanying the fall of the film portion 21c are in a molten state, so that a stronger sealing strength is obtained. be able to. In that case, by making the length from the deepest part of the first groove 61b to the outside of the flat part 61c equal to the length from the deepest part of the first groove 61b to the apex 61a ′ of the first protrusion 61a, The melted portions of the film portions 21c and 21d 'that come into contact with each other coincide.

  The second hem seal forming part 42 forms two fold lines in the formation region of the two inner hem seal parts 46 and heats the film, and a second fold line forming heating part 53 for heating the film. And a second press portion 54 that pressurizes the film portion folded so as to be folded along the folding line formed by the heating portion 53.

  As shown in FIGS. 5 and 8, the second fold line forming heating unit 53 includes a large-diameter disk-shaped third fold-line forming roller 71 disposed opposite to the band-shaped film 21 and two small-diameter disk-shaped rollers. Two pairs of fourth fold line forming rollers 72 are provided. The third folding line forming roller 71 is set to be positioned on the non-seal surface side of the belt-like film 21.

  The third fold line forming roller 71 is attached to a rotating shaft 73 with a built-in heater supported by a machine frame. The rotation shaft 73 is disposed so as to extend in a direction orthogonal to the conveyance direction of the strip film 21. The rotary shaft 73 is connected to a drive motor (not shown) and rotates in accordance with the transport speed of the belt-like film 21. Further, each third fold line forming roller 71 is movable independently in the axial direction of the rotation shaft 73. Then, by tightening the fixing screw at a desired position, the third fold line forming roller 71 is fixed to the rotating shaft 73 and rotates integrally. The rotating shaft 73 and the third fold line forming roller 71 are formed of a material having good thermal conductivity such as stainless steel or other metal, and the heat of the heater built in the rotating shaft 73 is applied to the third fold line forming roller. 71, the belt-like film 21 can be heated.

  The fourth fold line forming roller 72 is rotatably attached to the bearing plate 74. The bearing plate 74 is attached to a base base 75, and a slider (not shown) connected to the base base 75 matches a guide rail installed in parallel with the rotary shaft 73, and reciprocates along the guide rail. It is supposed to move. Therefore, when the slider (base table 75) is moved, the bearing plate 74 and, in turn, the fourth fold line forming roller 72 move in the lateral direction with respect to the belt-like film 21. That is, by this movement, the distance from the side edge of the position where the fourth folding line forming roller 72 contacts the belt-like film 21 toward the center can be adjusted.

  Further, the base base 75 is urged toward the third fold line forming roller 71 by an urging means such as a spring. Accordingly, the fourth fold line forming roller 72 is urged toward the third fold line forming roller 71 with a predetermined pressure.

  As a result, the third and fourth fold line forming rollers 71 and 72 are moved to appropriate positions, respectively, and the fold line forming rollers 71 and 72 come into contact with each other to sandwich an arbitrary position of the belt-like film 21 with a predetermined pressure. The film part can be heated. The fourth fold line forming roller 72 is in a free state, and receives the rotational force of the third fold line forming roller 71 that rotates as the rotating shaft 73 rotates (during the operation, the belt-like film 21 is removed). Via).

  These basic configurations are the same as those of the first fold line forming roller 61 and the second fold line forming roller 62. The second hem seal forming part 42 forms the two inner hem seal parts 46, and therefore the third fold line forming roller 71 and the fourth fold line forming roller 72 constituting the second fold line forming heating part 53 are: It is set so as to be positioned on the inner side of the first fold line forming roller 61 and the second fold line forming roller 62 constituting the first fold line forming heating part 51, that is, on the center side of the belt-like film 21.

  In order to form the inner hem seal portion 46, it is necessary to bend it on the side opposite to the outer hem seal portion 45, so that the circumferential surface of the third fold line forming roller 71, that is, the belt-like film 21 is formed. The circumferential surface of the 3rd protrusion 71a which protrudes in the shape of a mountain in the diameter direction outside (the other party) formed in the surface which counters, and the 4th fold line formation roller 62, ie, the surface which opposes beltlike film 21 The fourth protrusion 72a protruding in a mountain shape on the radially outer side (the other side) formed in the reverse of the arrangement order in the axial direction of the rotating shaft 73 is reversed.

  That is, the 3rd protrusion 71a and the 4th protrusion 72a consist of the shape which the substantially triangular mountain-shaped thing illustrated in figure showed the circumference made one round continuously. Further, the outer shape is asymmetric, and the opposing surface sides of both protrusions 71a and 72a are steep. And the 3rd protrusion 71a is set so that it may be located in the center side (axial direction center side of the rotating shaft 63) of the strip | belt-shaped film 21 with respect to the 2nd protrusion 72a.

  As shown in FIG. 8, the belt-like film 21 in a state in which the hem seal portion 45 is formed by folding the belt-like film 21 on the side edge side with the valley fold line 21a and the mountain fold line 21b, By passing between the folding line forming rollers 72, the rollers are sandwiched between the rollers 71 and 72. At this time, the belt-like film 21 is sandwiched and bent between the third ridge 71a and the fourth ridge 72a. That is, two fold lines of a mountain fold line 21e and a valley fold line 21f (based on the fourth fold line forming roller 72 side) are formed in this order from the side edge side of the belt-like film 21.

  Furthermore, in the present embodiment, the third fold line forming roller 71 has a third surface close to a portion facing the apex 72a ′ of the second ridge 72a, that is, a proximal end portion of the third ridge 71a. A concave groove 71b is formed. The third groove 71 b is formed continuously in the circumferential direction of the third fold line forming roller 71. Then, the vertex 72a ′ of the fourth protrusion 72a enters the third concave groove 71b. When the inner shape (cross section) of the third groove 71b and the outer shape (cross section) of the apex 72a 'of the fourth protrusion 72a are substantially matched and matched, the apex 72a' of the fourth protrusion 72a is set. As for the film part folded in, the mountain fold line 21e is firmly formed.

  Similarly, on the peripheral surface of the fourth fold line forming roller 72, a fourth groove 72b is formed in the vicinity of the portion facing the apex 71a 'of the third ridge 71a, that is, the ridge of the fourth ridge 72a. Has been. The fourth groove 72 b is formed continuously in the circumferential direction of the fourth fold line forming roller 72. Then, the vertex 71a ′ of the third protrusion 71a enters the fourth concave groove 72b. When the inner shape (cross section) of the fourth concave groove 72b and the outer shape (cross section) of the apex 71a 'portion of the third protrusion 71a are substantially matched and matched, the apex 71a' of the third protrusion 71a is set. The valley fold line 21f is firmly formed in the film portion folded in step.

  Moreover, the height of the 3rd protrusion 71a and the height of the 4th protrusion 72a are made to correspond substantially with the width | variety (protrusion length) of a hem seal part. By adopting the above configuration, as shown in FIG. 8B, the band-shaped film 21 passes through the second fold line forming heating unit 53, so that the mountain fold line is respectively formed inside the outer hem seal unit 45. Two pairs of 21e and valley fold line 21f are firmly formed. The distance between the mountain fold line 21e and the valley fold line 21f constituting the pair is the height of the third ridge 71a (= the height of the fourth ridge 72a) + α.

  Thus, the second fold line forming heating unit 53 (the center fold line 21f and the valley fold line 21f are firmly formed in that order in order from the outside of the belt-like film 21 (the center side is the valley fold line 21f). The film portion that has passed the third and fourth fold line forming rollers 71 and 72) is bent and deformed so that the portion of the mountain fold line 21e falls to the center side of the belt-like film 21 as shown in FIG. (The valley fold line 21f is located outside the mountain fold line 21e).

  Further, the belt-like film 21 is heated by the third fold line forming roller 71. As described above, one surface of the belt-like film 21 is a sealant surface, and the sealant surface comes to the third folding line forming roller 71 side. Furthermore, the flat part 71c, 72c is formed in the area | region outside the 1st, 2nd ditch | groove 71b, 72b of the surrounding surface of the 3rd, 4th fold line formation rollers 71, 72, These flat parts 71c, The belt-like film 21 comes into contact with 72c.

  Then, the steep surface of the third protrusion 71a and the film portion facing the third concave groove 71b and the flat portion 71c are firmly heated and melted in the belt-like film 21. As a result, the belt-like film 21 after passing through the second fold line forming heating unit 53 has a film fold line 21e sandwiched between the valley fold line 21f and the mountain fold line 21e because the mountain fold line 21e part falls to the center side of the film. Folds over the film portion 21h on the center side from the valley fold line 21f of the belt-like film 21, and this finally becomes the inner hem seal portion 46.

  Further, in the third fold line forming roller 71, the film portion facing the flat portion 71c provided on the peripheral surface thereof does not contact the flat portion 71c as shown in FIG. If it is parallel, it will come into contact with the flat part 71c as shown by the broken line). This is because the film portions on both side edges of the belt-like film 21 located on the outer side in the axial direction of the third folding line forming roller 71 may not be pinched by being pinched from both sides of the film. As shown, it does not contact the flat portion 62c. In particular, since the third fold line forming roller 71 is heated, when the film part touches the third fold line forming roller 71, the heat heated by the heater is directly applied to the film part, so that the keloid shape However, in the present embodiment, it can be suppressed.

  The central film portion of the belt-like film 21 is in contact with the flat portion 72c of the fourth fold line forming roller 72, which is relatively close to the flat portions 72c of the two fourth fold line forming rollers 72. It exists in a position and supports the film part of the strip | belt-shaped film 21 in the tensioned state.

  The second press unit 54 disposed on the downstream side of the second folding line forming heating unit 53 includes a pair of press rollers 54 a and 54 b disposed with the belt-like film 21 interposed therebetween. Although not shown, the pair of press rollers 54a and 54b is attached to a rotary shaft that is rotatably supported by a machine frame of a horizontal pillow packaging machine, and can be configured to rotate integrally. The press rollers 54a and 54b have a flat circumferential surface, and pressurize the region including the folded film portions 21g and 21h. As a result, the folded film portions 21g and 21h in the heated and melted state are pressurized, cooled, and firmly heat-sealed to form the two inner hem seal portions 46.

  Since the belt-like film 21 has only one surface as a sealant surface, the film portions 21g and 21h are generated by falling along the surface of the belt-like film 21 and the non-sealing surfaces of the belt-like film 21 are in contact with each other. Even if 21g and 21h 'are pressed by the pair of press rollers 54a and 54b, they are not heat-sealed.

  As shown in FIGS. 5, 9, and 10, the fold line forming unit 43, which is a fold line forming device disposed on the downstream side of the second hem seal forming unit 42, includes the first and second fold line forming heating units described above. The structure similar to 51 and 53 is taken, and the shape of the surrounding surface which contacts the strip | belt-shaped film 21 is made different from them. That is, the fold line forming unit 43 is a pair of a large-diameter disk-like fifth fold line-forming roller 81 and a small-diameter disk-like two sixth fold-line forming rollers 82 that are opposed to each other with the belt-like film 21 interposed therebetween. Two sets are provided. The fifth fold line forming roller 81 is attached to a rotating shaft 83 supported by bearings on the machine frame. The rotating shaft 83 is disposed so as to extend in a direction orthogonal to the transport direction of the strip film 21. The rotary shaft 83 is connected to a drive motor (not shown) and rotates in accordance with the transport speed of the belt-like film 21. Further, each fifth fold line forming roller 81 is movable independently in the axial direction of the rotation shaft 83. Then, by tightening the fixing screw at a desired position, the fifth fold line forming roller 81 is fixed to the rotating shaft 83 and rotates integrally.

  Note that the fold line forming unit 43 does not necessarily heat-seal the film portion near the fold line by simply adding a fold line, so the first and second fold line forming heating units 51 and 53 are not used. In addition, it is not always necessary to incorporate a heater in the rotary shaft 83, but the heater may be incorporated so that the belt-like film 21 can be heated to easily form a fold line (the form of the formed fold line can be easily maintained). That is, folding is performed by a folding line forming roller where the band-shaped film is softened by heat, and then the band-shaped film is cooled and the folded line is maintained.

  When the heater is built in, the rotary shaft 83 and the fifth folding line forming roller 81 are formed of a material having good thermal conductivity such as stainless steel or other metal, and the heat of the heater built in the rotary shaft 83 is changed to the first. It is efficient if it is transmitted to the 5-fold line forming roller 81 and the belt-like film 21 is easily heated. In addition, since heat sealing is not performed even when a heater is incorporated, the surface temperature of the fifth fold line forming roller 81 is set to be lower than the surface temperature of the first and third fold line forming rollers 61 and 71. It is better to adjust the heater temperature.

  The sixth fold line forming roller 82 is rotatably attached to the bearing plate 84. The bearing plate 84 is attached to the base base 85, and a slider (not shown) connected to the base base 85 matches a guide rail installed in parallel with the rotary shaft 83, and reciprocates along the guide rail. It is supposed to move. Therefore, when the slider (base stand 65) is moved, the bearing plate 64 and, in turn, the sixth fold line forming roller 82 moves in the lateral direction with respect to the belt-like film 21. That is, by this movement, the distance from the side edge of the position where the sixth folding line forming roller 82 contacts the belt-like film 21 toward the center can be adjusted.

  Furthermore, the base 85 is urged toward the fifth fold line forming roller 81 by an urging means such as a spring. Thereby, the sixth fold line forming roller 82 is urged toward the fifth fold line forming roller 81 with a predetermined pressure.

  As a result, the fifth and sixth fold line forming rollers 81 and 82 are respectively moved to appropriate positions, and the both fold line forming rollers 81 and 82 are brought into contact with each other so that an arbitrary position of the belt-like film 21 can be sandwiched with a predetermined pressure. (If the heater is built-in, the contacted film part can be heated). The sixth fold line forming roller 82 is in a free state, and receives the rotational force of the fifth fold line forming roller 81 that rotates as the rotating shaft 83 rotates (during the operation, the belt-like film 21 is removed). Via).

  As shown in FIGS. 9 and 10, the fifth fold line forming roller 81 has a circumferential surface in the circumferential direction, that is, a surface facing the belt-like film 21 as a flat surface as a whole, and a diameter at the center in the width direction. Two fifth protrusions 81a projecting in a small mountain shape are provided on the outer side (the other side) in the direction. The height of the fifth ridge 81a is sufficiently smaller than the other ridges 61a and 71a. A fifth groove 81b is formed between the two fifth protrusions 81a.

  Further, the sixth folding line forming roller 82 has a circumferential surface, that is, a surface facing the belt-like film 21 as a flat surface as a whole, and is small radially outward (partner side) at the center in the width direction. A sixth protrusion 82a protruding in a mountain shape is provided, and sixth concave grooves 82b are provided on both the left and right sides of the sixth protrusion 82a. The sixth protrusion 82a faces the fifth groove 81b of the fifth fold line forming roller 81, and the sixth groove 82b faces the fifth protrusion 81a of the fifth fold line forming roller 81. In the state of use, the protrusions enter into the concave grooves as shown in the figure.

  Furthermore, as shown in FIG. 10, the height a (the height from the tip of the protrusion 82a to the flat portion of the sixth fold line forming roller 82) and the height b (the flat portion of the sixth fold line forming roller 82). The height a> height b.

  If it does in this way, it will be in the state where the film was suppressed by the 5th ridge 81a on either side of the 5th fold line formation roller 81, and a fold line can be firmly formed with ridge 82a. That is, when this type of crease is usually applied, as shown in FIG. 1 (c), a pair of protrusions and grooves that match each other are provided on the peripheral surfaces of the pair of rollers that sandwich the belt-like film. The film is sandwiched between the ridges and the grooves so as to apply pressure, and then creases are applied. That is, in this embodiment, the belt-like film is pressed with a pair of the protrusion 82a and the concave groove 81b, and a fold line (folding crease) is applied. However, in the case of only one set of protrusion 82a and concave groove 81b, the mountain fold line 21j tends to be brazed to the belt-like film 21 along the tip of the protrusion 82a. In the case of a thin film or the like, after passing through the fifth and sixth fold line forming rollers 81 and 82, the belt-like film 21 spreads and the mountain fold line 21j is firmly attached to the mountain (fold). (Line) is not formed. On the other hand, in the present embodiment, the protrusions 81a and the recess grooves 82b are provided on both sides of the pair of protrusions 82a and the recess groove 81b, respectively, so that they are sandwiched between the fifth and sixth folding line forming rollers 81 and 82. The strip-shaped film 21 has two sets of opposite folds (valley fold lines 21k) on both sides along the folds (mountain fold lines 21j) formed by a pair of protrusions 82a and concave grooves 81b. Ridges 81a and concave grooves 82b. In this way, the two pairs of protrusions 81a and the groove 82b are bent in the opposite direction to the mountain fold line 21j formed by the pair of protrusions 82a and the groove 81b (to form a valley fold line 21K). Since the valley fold line 21k is formed at the base of the film portion that is bent around the mountain fold line 21j, the fold line is formed with a tight crease regardless of the strength of the waist of the film.

  Further, the protrusions 81a and 82a and the grooves 81b and 82b are positioned at a midpoint between the outer hem seal portion 45 and the inner hem seal portion 46 that form a pair formed up to the second hem seal formation portion 42. Is set. As a result, when the belt-like film 21 in which the hem seal portions 45 and 46 are formed passes through the fold line forming portion 43, a predetermined portion of the belt-like film 21 is pressurized by the rollers 81 and 82, and the ridges 81a, A fold line is formed at a location in contact with 82a. And since the recessed grooves 81b and 82b are arrange | positioned in the position facing the protrusion 81a and 82a, the fold line is formed firmly. As a result, as shown in FIG. 9B, the belt-like film 21 has a mountain fold line 21j formed at the center between the pair of hem seal portions 45, 46, and valleys on both sides of the mountain fold line 21j. A fold line 21k is formed. These one mountain fold line 21j and two valley fold lines 21k formed on both sides thereof correspond to the portion drawn as one fold line 47 in FIG.

  By passing through the hem seal device 40 in this way, the flat sheet-like belt-like film 21 fed out from the raw roll 20 is placed at appropriate positions on the hem seal portions 45, 46 and fold lines 47 (mountain fold lines 21j, The belt-like film 21 (see FIG. 9B) is formed with the valley fold line 21k), and the belt-like film 21 is supplied to the bag making device 24 of the packaging machine body 12. In each figure, the belt-like film 21 is drawn (folded) at a mountain fold line or a valley fold line, and the film part is drawn in a state where the film part is overlapped. This indicates the state of film folding. This is because, as is apparent from the above explanations, the film portions are actually in contact with each other, and the sealant surfaces of the belt-like film 21 are in contact with each other at the hem seal portion to be heat sealed. Therefore, the belt-like film supplied to the bag making machine 24 falls into the state where the hem seal portions 45 and 46 are also folded and overlapped with the film surface of the belt-like film 21 and become a substantially flat sheet. It moves smoothly without making a bag as shown in FIG. Note that FIG. 11 translates the folding direction of both side edges 21 ′ of the band-shaped film 21 and the positional relationship of the sealant surface when the band-shaped film 21 is formed into a cylindrical shape in relation to FIG. 9B. , The side edge 21 'is drawn upward. That is, in the state of FIG. 9B, the upper side in the figure is the sealant surface, and the bag is formed into a cylindrical shape by lifting both side edges 21 ′ upward from the state, so that the sealant surface becomes the packaging body. The hem seal portions 45 and 46 located parallel to the belt-like film 21 open outward (in the lateral direction of the package), and the mountain fold line 21j provided on the side surface is formed in a cylindrical shape. It can be configured to enter the inside of the package. However, as apparent from FIG. 3, the transport path of the belt-like film 21 is reversed on the downstream side of the fold line forming portion 43, and the sealant surface is turned upside down, so that it is actually supplied to the bag making machine 24. 9 (b), the top and bottom are reversed, and both side edges 21 'of the strip-shaped film 21 formed into a cylindrical shape are also opposite to those shown in FIG. Come to be located.

  In the present embodiment, by forming a pair of mountain fold lines and valley fold lines, it is possible to fold the film portion at the fold lines so as to be folded over the belt-like film 21. And, the film part A partitioned by the mountain fold line and the valley fold line, and the film part B of the sealant surface that faces the area when folded, constitutes a hem seal portion, Since it overlaps with the other region of the film 21, the film parts A and B can be heat-sealed only by pressing from both sides of the belt-like film 21. That is, since it is not necessary to sandwich only the film portions A and B from both sides as in the prior art, the film portions can be pressurized and sealed even if the width of the film portions A and B is narrow.

  Further, as the bag is made into a cylindrical shape in this way, the hem seal portions 45 and 46 rise and protrude outward from the body portion of the film formed into a cylindrical shape. In other words, the portion of the non-seal surface outside the belt-like film can stand up when the bag is made because it is not bonded even if it overlaps and comes in contact with the bag making device 24. By moving the packaging machine body 12 in this state, a pillow package with a hem seal portion in which hem seal portions 45 are formed at the four corners can be manufactured.

  In the above-described embodiment, the hem seal portions 45 and 46 are formed so as to protrude sideways. However, by reversing the formation order of the valley fold line and the mountain fold line, the hem seal portion of the film portion constituting the hem seal portion is formed. It is also possible to form the hem seal portions 45 and 46 so as to project in the vertical direction (vertical direction when the surface on which the end seal portion is formed is the bottom surface).

  In the embodiment described above, the hem seal portions are provided at the four corners. However, for example, two hem seal portions 45 on the side edge side of the belt-like film are provided (only the first hem seal formation portion 41 is installed as the device, and the second hem seal formation is performed). By providing a configuration in which the portion 42 and the fold line forming portion 43 are not provided), it is possible to manufacture a packaging form as shown in FIG. Thus, the installation number of hem seal parts is arbitrary, and the packaging body which consists of a new packaging form can be provided by changing the installation number.

  In addition, the first and second press portions 52 and 54 sandwich and press the predetermined portion of the belt-like film 21 with the pair of press rollers 52a, 52b, 54a and 54b, but the present invention is limited to this. However, only one of the press rollers 52a and 54a may be used. That is, the belt-like film 21 is stretched over various rollers 22 and is conveyed along a predetermined conveyance path. At this time, a state in which a certain tension is applied is maintained. Therefore, only the press roller 52a (54a) for changing the direction is used, and even if there is no roller (press roller 52b, 54b) for suppressing the strip film from the opposite side, the strip film 21 passes through the press rollers 52a, 54a. In addition, a certain tension is applied, and the product is cooled and heat-sealed. Of course, the press roller 52b, 54b can be pressed with a larger force, so that the heat can be reliably sealed with the force. Therefore, when the reliability of the heat seal is required, the configuration of this embodiment is adopted.

  Furthermore, in the above-described embodiment, the two outer hem seal portions are formed by the first hem seal forming portion 41, and the two inner hem seal portions are formed by the second hem seal forming portion 42. This pattern can be easily conveyed while taking the center of the belt-like film 21, but the inner side may be formed first. One half (for example, two hem seal portions on the left side) is formed first, and then the remaining one half (for example, two hem seal portions on the right side) is formed, or positioned on a diagonal line in the package It may be formed by a pair of hem seal portions. Regardless of which pattern is used, in this embodiment, each fold line forming roller provided in the first hem seal forming portion 41 and the second hem seal forming portion 42 can move independently in the axial direction. This can be done simply by setting the position of the roller to the final hem seal portion formation position.

  In the above-described embodiment, since it is incorporated into a horizontal pillow packaging machine that manufactures a packaging body with the hem seal portion 45, the middle of both side surfaces of the packaging body is folded inward by the folding line forming device (folding line forming portion 43). For this reason, the fold line 47 is formed at the central portion of the both side surfaces, but the present invention is not limited to this, and for example, a packaging body in which a hem seal portion is not formed as shown in FIG. The present invention can also be applied to a case in which fold lines are formed at film portions corresponding to the four corners in the case of manufacturing a package of a type with creases at the four corners.

  In this case, the folding direction of the fold lines formed at the four corners is opposite to that formed at the center, so that the formation positions of the large and small ridges / grooves are opposite to those of the fold line forming portion 43. become.

  Furthermore, as disclosed in Patent Document 1 and the like, an apparatus for forming a fold line in a direction orthogonal to the transport direction of the belt-like film is also provided on both sides of a pair of protrusions and grooves as in the present invention. A mechanism for forming two sets of concave grooves and ridges can be used.

DESCRIPTION OF SYMBOLS 10 Horizontal pillow packaging machine 11 Product conveyance supply apparatus 12 Packaging machine main body 13 Film supply apparatus 14 Product 21 Strip film 40 Hem seal apparatus 41 First hem seal formation part 42 Second hem seal formation part 43 Fold line formation part 45 Hem seal part (outside)
46 Hem seal (inside)
47 Folding line 51 First folding line forming heating part 52 First press parts 52a, 52b Press roller 53 Second folding line forming heating part 54 Second pressing parts 54a, 54b Press roller 61 First folding line forming roller 61a First protrusion Strip 61b First groove 61c Flat portion 62 Second folding line forming roller 62a Second protrusion 62b Second groove 63 Rotating shaft (built-in heater)
71 3rd fold line formation roller 71a 3rd protrusion 71b 3rd groove 71c Flat part 72 4th fold line formation roller 72a 4th protrusion 72b 4th groove 73 Rotating shaft (built-in heater)
81 Fifth fold line forming roller 81a Fifth ridge 81b Fifth groove 82 Sixth fold line forming roller 82a Sixth ridge 82b Sixth groove 83 Rotating shaft

Claims (3)

A fold line forming apparatus for a wrapping film that is provided in the middle of the transport of the strip film in the packaging machine and forms a fold line at a predetermined position of the strip film,
A pair of fold line forming rollers disposed opposite to each other with the belt-like film interposed therebetween;
On the circumferential surface of the one fold line forming roller, there are provided protrusions A protruding radially outward, and concave grooves A are formed on both axial sides of the protrusion A,
On the circumferential surface of the other folding line forming roller, a groove B is provided at a portion facing the protrusion A, and a protrusion B is provided at a portion facing the groove A.
A fold line is formed in the band-shaped film by sandwiching the strip-shaped film between the ridge A and the concave groove B, and along the fold line by sandwiching the strip-shaped film between the ridge B and the concave groove A. A fold line forming apparatus for a packaging film, wherein an auxiliary fold line is formed that is folded in a direction opposite to the fold line.   The height of the protrusion A from the circumferential surface of the circumferential direction of the one folding line forming roller is longer than the depth of the concave groove A from the circumferential surface. Fold line forming device for packaging film.   The packaging film according to claim 1 or 2, wherein heating means is provided on at least one of the pair of folding line forming rollers to heat the belt-shaped film sandwiched between the pair of folding line forming rollers. Fold line forming device.

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