JPH04118302U - Vertical sealing device - Google Patents

Abstract

(57) [Abstract] [Purpose] A vertical sealing device that prevents the overlapped ends from shrinking too much and curling when heat sealing the overlapped ends of a cylindrical film formed using a film material with good heat shrinkability. [Structure] Consisting of a relatively large diameter heating roller 21 and two small diameter receiving rollers 22, 22 disposed opposite to the heating roller with the overlapping end 7a of the cylindrical film 7' in between. be done. Three annular protrusions 23 are formed on the side peripheral surface of this heating roller. As a result, concave grooves 24 are formed between the protrusions that do not contact the overlapping end, and the overlapping end of the cylindrical film is held and heated between the three protrusions and a receiving roller having a flat side surface. This prevents heat from being applied to the entire surface of the polymerized end and reduces the amount of heat applied to the film.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to a vertical sealing device, and in particular uses a film material with good heat shrinkability. When manufacturing packaging bodies or packaging bags using Vertical sealing device used to heat seal film overlapping edges formed in the direction Regarding.

0002

[Conventional technology]

Conventional vertical sealing devices, for example, use a pair of sealers as flat cylindrical rotating rollers. The overlapping end of the cylindrical film is sandwiched between the side peripheral surfaces of both rotating rollers. ing. Therefore, both rotating rollers are in line contact with the overlapping end. . Also, one of the pair of rotating rollers usually has a heating means such as a heater inside. One is a heating roller with built-in heating means, and the other is a receiving roller without built-in heating means. It has become. The side circumferential surfaces of both rotating rollers are flat and flush, and the rotating rollers are flat and flush. The overlapping end will be sealed over the entire width of the roller, and the sealing width at the overlapping end will be the same as the rotating roller. equal to the width of the ra.

0003 On the other hand, it is composed of a pair of substantially elongated prismatic sealers, and one side of the sealer is By arranging them facing each other, it is possible to make surface contact with the overlapping end of the cylindrical film. Some have a similar structure. Even in the case of a vertical sealing device with such a configuration, the facing surface of the sealer is flat. As expected, the overlapping edge will be sealed over the entire width of the sealer. , the seal width at the overlapped end will be equal to the width of the sealer.

0004

[Problem that the idea aims to solve]

However, in the conventional vertical sealing device described above, the polymerization of the sealer and film The contact area with the ends increases, and the amount of heat applied to the overlapping ends increases. Then, for example For film materials with good heat shrinkability such as shrink film, the above conventional When using a vertical sealing device, the overlapping ends may shrink too much due to the heat during heat sealing and curl up. There is a risk that the thickness of that area will increase. In such cases, the cylindrical film is When manufacturing a package or a packaging bag by sealing it in the lateral direction, the thickness increases. Not only is it necessary to crush the pressed part to eliminate the level difference between it and other parts, but it is also necessary to Since it is difficult to perform the crushing process completely, it is difficult to perform a complete end seal. The problem is that it is not possible.

[0005] Furthermore, even if a perfect end seal can be achieved, the final packaging There is a single curled vertical seal part on the package or packaging bag, and the curled This part is thicker than other parts, so it protrudes outward, which makes it difficult to look good. There is also the problem that the product value decreases due to poor performance. This invention was made in view of the above-mentioned background, and its purpose is to: Heat-seal the overlapping ends of a cylindrical film formed using a film material with good heat shrinkability. Provides a vertical sealing device that prevents the overlapping ends from contracting too much and curling when It's about doing.

[0006]

[Means to solve the problem]

In order to achieve the above-mentioned purpose, the vertical sealing device according to the present invention has heat shrinkability. The same side as the traveling direction of the cylindrical film formed into a cylindrical shape using a good strip film. A pair of sheets are arranged on both sides of the overlapping ends formed in the direction, and at least one of them is heatable. The polymerization end is sandwiched between a pair of sealers and heated to seal the polymerization. In a vertical sealing device for heat sealing edges, the polymerization of at least one of the sealers It is characterized by forming a concave groove along the traveling direction on the end facing surface.

[0007]

[Effect]

A concavity along the direction of film travel on the surface facing the overlapping end of at least one sealer. Since the grooves are formed, the actual heating area for the overlapping ends is reduced. Therefore , even if vertical sealing is performed on a highly heat-shrinkable film, the amount of heating is The overlapping edge is partially heat-sealed in the width direction, and the overlapping edge is heated and compressed more than necessary. It will not shrink and curl up. In addition, multiple seal portions with narrow seal widths are formed at the overlapped end. This ensures reliable sealing and the overall total seal width is the same as that of the conventional one.

[0008]

【Example】

The attached drawings below will explain preferred embodiments of the vertical sealing device according to the present invention. The details will be explained with reference to. Figure 1 shows a shri using the center seal device, which is the vertical seal device of the present invention. 1 shows an example of a link packaging device. As shown in the figure, the upper part of the tray is expanded. - a conveying device 4 that conveys a packaged article 3 in which articles 2 are stored at predetermined intervals; An end sealing device 5 is disposed in front of the belt in the direction of movement, and above the conveying device 4 is a belt sealing device 5. A raw film 8 in which the shaped film 7 is wound is disposed, and an end sealing device is further provided. A shrink tunnel 10 is provided on the discharge end side of the container 5.

[0009] The strip-shaped film 7 has low gas permeability, that is, gas barrier property. Film materials with good heat shrinkability, such as BDF-2050 (cryoba (manufactured by Co., Ltd.) is used. Then, the strip film 7 is pulled out by a pull-out roller 12. and a plurality of tension rollers 13 disposed at an intermediate point of the conveying device 4. A cylindrical film is formed in the bag making machine 14 to become a cylindrical film 7', and this cylindrical film is The items to be packaged are sequentially supplied and stored in the film 7' and then transported further. There is.

0010 Further, the conveying device 4 conveys only the object 3 to be packaged, and transfers the object 3 to the cylindrical film 7. ' A first conveying device 15 that sequentially supplies the inside, and a first conveying device 15 that sequentially supplies A second conveyance device that is arranged close to each other and conveys the packaged object 3 together with the cylindrical film 7'. It consists of 16. The first conveyance device 15 has a pair of sprockets. The endless chain 18 installed on the The fingers 19 are arranged at predetermined intervals of the fingers 18. Further, the second conveying device 16 has a weight of the cylindrical film 7' below near the carry-in side. A center seal device 20 is provided for sealing the mating end 7a.

[0011] Here, the center seal device 20 according to the present invention will be explained. The tar seal device 20 pinches the overlapping end 7a of the cylindrical film 7' from both sides. Heat-sealed by heating and melting the bonding surface of the film. Specifically, the structure is shown in FIGS. 2 and 3.

0012 That is, a relatively large-diameter heating roller 21 and a heating roller sandwiching the overlapping end 7a are connected. It is composed of two small-diameter receiving rollers 22, 22 arranged opposite to the roller 21. It will be done. The reason why the two receiving rollers 22, 22 are provided in this way is to ensure that the overlapping end 7a is This is for heat sealing.

[0013] Three annular protrusions 23 are formed on the side peripheral surface of the heating roller 21. Ru. As a result, a groove 24 along the direction of movement of the overlapping end 7a is formed between the protrusions 23. be done. Then, a receiving roller 22 having the three protrusions 23 and a flat side circumferential surface , 22, and heat the polymerized end 7a of the cylindrical film 7'. This prevents heat from being applied to the entire surface of the end 7a, thereby reducing the amount of heat applied to the film. vinegar That is, because the film material 2 used has high heat shrinkability (50 to 6 If the amount of heating is large, the overlapping end 7a will shrink too much and become rounded. The thickness of the area will increase, and if left as is, a complete end seal will be required in the later process. However, by reducing the amount of heating as described above, the center seam The end seal is made flat so that the end seal can be reliably sealed.

[0014] Furthermore, in this example, the heat generated from the heating roller 21 is transferred to the cylindrical film 7'. It is added to the part located on the bottom side of the film 1 to prevent the film part from shrinking due to heat. In order to prevent this, a pair of left and right parts are provided between the center seal device 20 and the tubular film 7'. Cooling plates 25, 25 are provided.

[0015] This cooling plate 25 has a flat upper plate, a lower plate 26, 27, and a space between the two plates 26, 27. The middle plate 28 has a three-layer structure and has a meandering window hole 28a. No. 8 window holes 28a serve as cooling passages. At a predetermined position on the lower plate 27, A cooling water supply port 27a and a discharge port 27b are formed for the cooling water channel, and both ports 27 A pump 30 and a tank 31 are connected to a and 27b via a connecting pipe 29. . As a result, these cooling water passages, connecting pipes 29, pumps 30, and tanks 31 Cooling water circulates within the closed circuit. Note that in this example, cooling Tap water is used as water. Then, the overlapping end 7a of the cylindrical film 7' is inserted into the gap between the two cooling plates 25, 25. and is supplied between both rollers 21 and 22 located below the cooling plates 25 and 25. It has become so. Note that the pump 30 is always operated to cool the shrink packaging machine while it is in operation. Water is circulated, but it may also be operated intermittently or discontinuously. Furthermore, the cooling water is not circulated as in this embodiment, but is supplied and released sequentially. It may also be configured such that

[0016] In addition, the end seal device 5 used in this shrink packaging device is uses a so-called Bock motion type end seal device, and the specific configuration is as follows. It is as shown in FIG. That is, a pair of upper and lower end sealers 35, 36 A cutting blade is built into the sealing surface of the upper end sealer 35. Ma Both end sealers 35 and 36 are connected to groove cams 37 and 37, and both end sealers - 35 and 36 move forward while meshing with each other, then move backward while separating. It rotates along a predetermined trajectory. In addition, the lower end Around the roller 36, a large number of fixed and movable pulleys 39a and 39b are installed. An endless belt 40 is provided, and an upper conveying surface 40 of the endless belt 40 A cylindrical film 7' is received and conveyed on a. further down The space 40b of the endless belt 40 formed around the end sealer 36 is The moving pulley 39b is moved back and forth in synchronization with the back and forth movement of the lower sealer 36. By doing so, the lower sealer 36 moves back and forth to close the space 40. By shortening the opening distance of b, smooth movement of the cylindrical film 7', etc. is achieved.

[0017] Furthermore, in this embodiment, the end sealer 35 on the upper side of the end seal device 5 is A film pressing member serving as a film urging device is provided on the front surface in the traveling direction via a connecting plate 42. 43 are installed. This film holding member 43 is made of a rectangular sponge. The shape is set smaller than the planar shape of the tray 1. Also, its thickness is the meshing state of both end sealers 35 and 36, that is, the upper end sealer 35 is at the lowest end, the lower surface of the film holding member 43 is higher than the upper surface of the tray 1. It is set to be located at the bottom.

[0018] Further forward in the traveling direction of the film restraining member 43 is the shrink tunnel described above. This shrink tunnel 10 has vertical openings in the front and back. A normal one with a roughly gate-shaped cross section is used, and below the shrink tunnel 10, A conveyor belt 45 is provided, and the end sealing device 5 separates the cylindrical film from the cylindrical film 7'. The separated and manufactured intermediate packaging body 46 is conveyed. And the transportation An unloading conveyor 48 is disposed near the unloading end of the conveying belt 45. The shrink package 50 manufactured by passing through the inside of the flannel 10 and being heat-shrinked is carried out. It looks like this.

[0019] Next, to explain the operation of the above-mentioned embodiment, first, from the original film 8 to the strip The strip-shaped film 7 is continuously drawn out and a through hole is formed in the strip-shaped film 7. The film is guided to the bag making device 14 without any problems, and is formed into a cylindrical shape there to become a cylindrical film 7'. Ru. On the other hand, the object to be packaged 1 is pushed by the fingers 19 and conveyed at predetermined intervals, and is sequentially It is supplied into the cylindrical film 7'. In this state (the state in which the packaged object 3 is stored in the cylindrical film 7'), the second As it is transported on the transport device 16, the overlapped end 7 of the cylindrical film 7' While the heating rollers 21 and receiving rollers 22 arranged on the left and right hold the a Heat seal.

[0020] At this time, in the present invention, first, the receiving roller 22 on the bag making machine 14 side and the heating roller 21, the overlapping end 7a of the cylindrical film 7' is held and heated, and then both After the nip from the rollers 21 and 22 is released (at this time, the overlapping end 7a is (in contact with the roller 21), between the other receiving roller 22 and the heating roller 21 Then, the overlapping ends 7a are again clamped and heated to be completely heat-sealed. And actually the cylinder The heating roller 21 is in pressure contact with the overlapping end 7a of the shaped film 7'. This is only the joint portion between the three protrusions 23 and the receiving roller 22, and the overlapping end 7a This prevents heat from being applied to the entire surface of the film, reducing the amount of heat applied to the film. this As such, heat sealing is performed partially in the width direction of the overlapping end 7a.

[0021] Therefore, the overlapping end 7a sealed by the center seal device 20 is shown in FIG. As shown in the enlarged view, along the traveling direction of the cylindrical film 7', that is, in the longitudinal direction. It has a substantially flat shape in which three extending seal portions 7a' are formed. And cylindrical fill The degree of sealing of the seal 7' is determined by forming the seal part 7a' vertically as described above. This allows for complete sealing.

[0022] Moreover, when the cylindrical film 7' passes over the center sealing device 20, in this example, has a cooling plate 25 between the heating roller 21 and the cylindrical film 7', and furthermore, Since cooling water is circulated inside the cooling plate 25, the heating roller 21 The generated heat is not transmitted to film parts other than the overlapping end 7a of the cylindrical film 7'. stomach. In other words, the film material used in this example has extremely high heat shrinkability, so it is simply cooled. If you just place the plate members for the purpose, you cannot expect a complete heat insulation effect, 7' may shrink due to heat, so ensure that the insulation is properly insulated by circulating cooling water. I try to do that.

[0023] Then, when the film is further moved forward, the end sealing device 5 causes the cylindrical film 7' to be horizontally moved. The intermediate packaging body 46 is manufactured by heat sealing and cutting at predetermined intervals in the direction. . At this time, when sealing the end seal on the rear side in the direction of travel, be sure to The upper surface of the cylindrical film 7' is urged downward via the restraining member 43 to make it hollow inside. (See Figure 5). From this state, both end sealers 35 and 36 further rotate, The two mesh to form an end seal (see Figure 6), creating a film as shown in Figure 7. An intermediate package 46 having a concave upper surface is manufactured. That is, the inside of the intermediate packaging body 46 In addition to reducing the amount of gas present, taking into account that the cylindrical film 7' will shrink due to heat, It has an extra layer of film.

[0024] Then, the intermediate package 46 is conveyed via an endless belt 40 and a conveyor 45. and supplied into the shrink tunnel 10. This shrink tunnel 10 is Since the temperature on the side is particularly high, the cylindrical film 7' shrinks due to heat, especially on the top surface. Shrink to width. As a result, as shown in FIG. The film will become taut. Also, at this time, the intermediate packaging body 4 The gas that existed within 6 thermally expands, but as the top of the film rises, the new gas expands. Since the film flows into the upper space 51 defined above, the upper surface of the film is above the tray 1. It will not swell.

[0025] As a result, the cylindrical film 7' is heat-shrinked and the shrink packaging is brought into close contact with the tray 1. A body 50 is manufactured. The manufactured shrink packaging body 50 has through holes formed therein. Since it is a completely sealed bag, it can be shrink-wrapped using a gas exchange device. There is no risk that nitrogen gas or the like filled in the interior of the housing 50 will leak out to the outside. Furthermore, the overlapping end 7a in the final shrink package 50 is as shown in FIG. In other words, it maintains a flat shape with three seal portions 7a'.

[0026] FIG. 10 shows another embodiment of the present invention. This example differs from the above example. Then, the heat insulating material 60 is filled and arranged in the groove 24' formed in the heating roller 21'. are doing. By doing this, the parts other than the protrusion 23' of the heating roller 21' By dissipating heat from the part, it is possible to prevent the overlapping end 7a from being heated more than necessary. are doing. Note that the other configurations and functions are the same as those of the first embodiment, so the explanation will be omitted. Omitted.

[0027] In addition, in each of the above embodiments, the sealer was applied to a pair of flat cylindrical rollers. , and a heating means is provided only on one side. However, the present invention is not limited to this, and both rollers may be provided with heating means, Furthermore, instead of a rotating roller, it is composed of a pair of approximately slender prismatic sealers. By placing one side of the sealer facing each other, polymerization of the cylindrical film is prevented. The structure may be such that it makes surface contact with the end, and its structure is arbitrary.

[0028] In addition, the films used are not limited to the above examples. Needless to say, the heat shrinkage rate also depends on the size and shape of articles, trays, etc., as well as intermediate packaging. The relationship between the amount of space in which gas exists in the body and the amount of space in the final shrink package. This will be determined as appropriate. Then, depending on the shrinkage rate of the film used, etc., the heating roller 21 is formed. It is preferable that the number, width, etc. of the protrusions 23 are arbitrarily determined and changed.

[0029] Furthermore, as a packaging device in which the vertical sealing device of the present invention is used, the above-mentioned pin Not limited to low-wrap type shrink wrapping equipment, regular pillow packaging equipment can also be used. Of course, for example, one strip-shaped film is bent into a roughly U-shape, and one side edge in the direction of travel is folded. Packaging equipment for so-called three-way seals in which overlapping ends are formed at the ends, and packaging equipment for two strip-shaped films. The so-called 4-frame construction is a so-called 4-frame construction in which the overlapping ends are formed on both edges in the direction of travel. It can be applied to various things such as packaging devices for side seals. In other words, the term "cylindrical film" as used herein includes the above-mentioned flat film. It is a broad concept.

[0030] Furthermore, the present invention is not limited to the various packaging devices mentioned above, but can also be used to insert objects to be packaged. The present invention can also be applied to a bag-making device for manufacturing only bags without any waste.

[0031]

[Effect of the idea]

As described above, in the vertical sealing device according to the present invention, at least one sealer Since a concave groove is formed along the direction of movement on the surface facing the overlapped end, the contact area with the overlapped end is reduced. Even if vertical sealing is performed on highly heat-shrinkable films, Even if the overlapped ends are partially heat-sealed in the width direction, the amount of overheating can be suppressed. This prevents the overlapping ends from heating and shrinking more than necessary and curling up. Ru. In addition, multiple seal portions with narrow seal widths are formed at the overlapped end. This allows for reliable sealing, and the overall seal width is lower than that of conventional ones. It will be the same.

[Brief explanation of drawings]

FIG. 1 is a side view showing a preferred embodiment of a shrink packaging device in which a center seal device, which is a vertical seal device according to the present invention, is used.

FIG. 2 is a plan view showing the vicinity of the center seal device according to the present invention.

FIG. 3 is a front view of FIG. 2;

FIG. 4 is a side view showing the vicinity of the end seal device of this embodiment.

FIG. 5 is a diagram illustrating the operation of the end seal device of this embodiment.

FIG. 6 is a diagram illustrating the operation of the end seal device of this embodiment.

FIG. 7 is a side view showing an intermediate package manufactured by the present apparatus.

FIG. 8 is a side view showing a shrink package manufactured by this apparatus.

9 is a perspective view of the shrink package shown in FIG. 8. FIG.

FIG. 10 is an enlarged sectional view of main parts showing another embodiment of the center seal device according to the present invention.

[Explanation of symbols]

7' Tubular film 7a Overlapping end 20 Center seal device (vertical seal device) 21, 21' Heating roller (a set of sealers) 22, 22' Receiving roller (a set of sealers) 24, 24' Concave groove 25 Cooling plate 28a Cooling water passage 60 Insulation material

Claims (3)

[Scope of utility model registration request] [Claim 1] A belt-shaped film having good heat shrinkability is formed into a cylindrical shape, and at least one side of the overlapping end is formed in the same direction as the traveling direction of the cylindrical film. In a vertical sealing device having a set of sealers, the set of sealers sandwich the overlapping end and heat the overlapping end to heat-seal the overlapping end. A vertical sealing device characterized by forming a concave groove along the . 2. The vertical sealing device according to claim 1, further comprising a heat insulating material installed in the groove. 3. A cooling plate is disposed between the set of sealers and the cylindrical film portion near the overlapping end, and a cooling water passage is disposed inside the cooling plate. The vertical sealing device according to claim 1 or 2.