JP7624222B2 - Top Seal Device - Google Patents

Description

The present invention relates to a top seal device.

A pillow packaging machine, which is one type of packaging machine, continuously supplies a strip-shaped packaging material wound on a roll of raw material, for example, to a bag maker, and forms a cylindrical bag as it passes through the bag maker. Then, a center seal device arranged downstream of the bag maker seals the area where the packaging material is formed into a cylindrical bag through the bag maker and the side edges of the packaging material are overlapped. Also, a product conveying and supplying device is arranged upstream of the bag maker, and products conveyed from the product conveying and supplying device at predetermined intervals are supplied to the bag maker. As a result, when the products pass through the bag maker, they are stored in the cylindrical packaging material at predetermined intervals, and the products are conveyed together with the cylindrical packaging material. Then, a top seal device arranged on the discharge side of the pillow packaging machine seals and cuts the cylindrical packaging material so as to cross the horizontal direction at predetermined intervals, thereby producing a pillow package containing the product. An example of such a top seal device is disclosed in Patent Document 1.

JP 2009-83883 A

For example, in the case of a top seal device disclosed in Patent Document 1, where the sealing and cutting processes for cylindrical packaging material are performed together in one device, the packaging material is sandwiched between the sealing surfaces at the tips of a pair of top sealers and then heated and pressurized to thermally seal it, and while still sandwiched in this state, the tip of a cutter blade built into the top sealer is protruded beyond the sealing surfaces and the cutting edge of the cutter blade is pressed against the packaging material to cut it.

However, depending on the type of packaging material, it may not be possible to cut it neatly. This is especially true when the packaging material is made of a material that does not stretch easily, such as paper. Therefore, there is a need to develop a top seal device that can cut neatly regardless of the type of packaging material.

The above-mentioned problems are described as being independent of each other, and the present invention does not necessarily have to solve all of the problems described, but it is sufficient if it can solve at least one of the problems. In addition, we intend to obtain rights to the configuration for solving this problem separately through divisional applications, amendments, etc.

In order to solve the above-mentioned problems, the top sealing device of the present invention is (1) a top sealing device that seals and cuts a packaging material containing a product in a direction intersecting the conveying direction of the packaging material, and includes a first top sealer and a second top sealer arranged to sandwich the packaging material, and a top cutter mounted so as to be able to appear and disappear from the sealing surface of the tip of the first top sealer, the sealing surface of the first top sealer is provided with first convex portions extending in the conveying direction and first concave portions extending in the conveying direction alternately in a direction intersecting the conveying direction, and the sealing surface of the second top sealer is provided with second convex portions extending in the conveying direction. and a second concave portion extending in the conveying direction are alternately provided in a direction intersecting the conveying direction, and when the first top sealer and the second top sealer sandwich the packaging material, the first convex portion and the second concave portion face each other, and the first concave portion and the second convex portion face each other, the tip sides of the first convex portion and the second convex portion have flat portions, the inner sides of the first concave portion and the second concave portion have flat portions, and a number of blade portions having tapered tips are arranged at a predetermined pitch on the tip side of the top cutter in a direction intersecting the conveying direction, and the pitch is configured to be an integer multiple of the arrangement pitch of the first convex portions or the first concave portions. In this way, each blade tip of the top cutter comes into contact with the packaging material at the same timing and cuts into it, so that the packaging material can be neatly cut.

(2) It is preferable that each cutting edge of the blade portion is configured to match the formation position of the first convex portion in the direction along the conveying direction. In this way, the cutting edges push up/down the peaks of the packaging material to cut, resulting in a sharper cutting edge.

According to the present invention, the sharpness of the top cutter can be improved regardless of the type of packaging material.

FIG. 1 is a front view showing a preferred embodiment of a system in which a top seal device according to the present invention is implemented. (a) is a view of the top sealing device from the upstream side, (b) is a partially enlarged view of the plan view of the lower top sealer, and (c) is a partially enlarged view from the upstream side showing the packaging material sandwiched between the upper top sealer and the lower top sealer. FIG.

The following describes in detail a preferred embodiment of the present invention with reference to the drawings. Note that the present invention is not to be interpreted as being limited to this embodiment, and various changes, modifications, and improvements may be made based on the knowledge of those skilled in the art without departing from the scope of the present invention.

Figures 1 to 3 show a preferred embodiment of the top sealing device according to the present invention and a pillow packaging machine in which it is implemented. The pillow packaging machine 10 is configured with a product conveying and supplying device 11 and a packaging machine main body 12 arranged in that order from the upstream side, and a packaging material supplying device 14 above them.

The product conveying and supplying device 11 is formed from a finger conveyor device that conveys products 13 at regular intervals and sequentially supplies them to the packaging machine body 12 of the next stage. That is, it is configured by attaching push fingers 9 at regular intervals to an endless chain 8 stretched between sprockets 7 arranged in front and behind (only the downstream side is shown in Figure 1). Then, by supplying products 13 between the front and rear push fingers 9, the products 13 are conveyed at the finger pitch of the push fingers 9.

The packaging material supply device 14 is for continuously supplying the strip-shaped packaging material 16 for wrapping the product 13 to the packaging machine main body 12. This packaging material supply device 14 is provided with a support means for the original roll 15 on which the strip-shaped packaging material 16 is wound into a roll. The packaging material supply device 14 is provided with rollers 17 (only one is shown in the figure) for transporting the strip-shaped packaging material 16 continuously drawn from the original roll 15 along a predetermined transport path and guiding it to the loading portion of the packaging machine main body 12. The rollers 17 include a drive roller that applies drive to the strip-shaped packaging material 16, a tension roller that applies tension, and a free roller that changes the transport direction of the strip-shaped packaging material 16 and guides the transport. Furthermore, the packaging material supply device 14 is disposed above the bag maker 22 and supplies the packaging material 16 from above. Also, instead of directly driving the packaging material 16 to pull it out, the support shaft of the raw roll 15 may be connected to a drive motor such as a servo motor, and the raw roll 15 may be rotated to unwind the packaging material 16. In this embodiment, the packaging material 16 is made of a material that is difficult to stretch, such as paper, but it is not limited to paper or other materials that are difficult to stretch, and various films and the like may be used. In the case of paper, it is preferable to have a sealant layer on the inner surface when formed into a cylindrical shape.

The packaging machine main body 12 is equipped with a bag former 22 on the carry-in side. The bag former 22 forms the strip-shaped packaging material 16, which is continuously supplied from the packaging material supply device 14, into a cylindrical shape. As the packaging material 16 passes through the bag former 22, both side edge portions 16a of the packaging material 16 are overlapped and protrude below the conveying surface of the bag former 22.

Meanwhile, the products 13 successively conveyed out of the product conveying and supplying device 11 are supplied into the bag making machine 22. As a result, the products 13 are supplied at predetermined intervals into the packaging material 16 being made into a cylindrical bag, and thereafter, the products 13 are conveyed together with the packaging material while remaining enclosed within the cylindrically made packaging material 16.

The packaging machine main body 12 further includes a center seal device 23 downstream of the bag maker 22. The center seal device 23 seals the overlapping portions of both side edge portions 16a of the tubular packaging material 16 that has passed through the bag maker 22 and been made into bags. This center seal device 23 is configured with an entrance pinch roller 23a, a bar-shaped center sealer 23b, and an exit pinch roller 23c arranged, in order from the upstream side, at predetermined positions below a pair of left and right upper plates that form the conveying surface.

The pair of left and right entrance pinch rollers 23a sandwich the overlapping portion of the downwardly protruding side edge portions 16a of the packaging material 16 from the left and right to apply a conveying force. The pair of left and right center sealers 23b, for example, have built-in heaters and sandwich and heat the side edge portions 16a from both sides. The pair of left and right exit pinch rollers 23c sandwich the side edge portions 16a heated by the center sealer 23b from both sides to apply a conveying force. Furthermore, in order to apply this conveying force, the portion heated and melted by the center sealer 23b is pressurized and cooled to complete the heat seal. The exit pinch rollers 23c are also called press rollers. In this embodiment, the center seal device 23 uses a bar-shaped center sealer 23b, but it can also be composed of a pair of rotating rollers, and can have various structures.

The side edge portions 16a of the packaging material 16 made into a cylindrical bag by the bag making machine 22 are sealed by the center seal device 23, and the packaging material 16 is closed in the direction of rotation of the packaging material perpendicular to the packaging material conveying direction.

The packaging machine body 12 is equipped with a lower belt conveyor device 26 and an upper hold-down belt device 28 downstream of the center seal device 23. The lower belt conveyor device 26 constitutes a transport path for the packaging material 16 containing the product 13. The upper hold-down belt device 28 is disposed at a predetermined position above the lower belt conveyor device 26.

The packaging machine main body 12 further includes a top seal device 30 downstream of the lower belt conveyor device 26 and the upper holding belt device 28. The top seal device 30 seals and cuts the packaging material 16 in a direction perpendicular to the conveying direction, i.e., in the transverse direction. The sealing and cutting portion is a predetermined position between the preceding and succeeding products 13. By the cutting process by this top seal device 30, the leading end portion of the packaging material 16 (the portion containing the leading product 13) is separated from the succeeding packaging material 16, and a package 29 is produced. This package 29 is then transported on the discharge conveyor device 27.

The top sealing device 30 will be described below. The top sealing device 30 of this embodiment is a so-called box motion type, in which the upper top sealer 31 and the lower top sealer 32, which are arranged opposite each other with the cylindrical packaging material 16 sandwiched between them, have built-in heaters and move along a predetermined trajectory while maintaining their sealing surfaces 311, 321 facing each other by a predetermined drive mechanism. In other words, the upper top sealer 31 and the lower top sealer 32 move toward each other from a reference position to sandwich the packaging material 16 from above and below, and pressurize and heat the parts that come into contact with the sealing surfaces 311, 321 with a predetermined pressure. Then, the upper top sealer 31 and the lower top sealer 32 move forward along the moving direction of the packaging material 16 while maintaining the state of being close to each other and sandwiching the packaging material 16 as described above. The moving speed at this time is equal to the moving speed of the packaging material 16. After the upper top sealer 31 and the lower top sealer 32 move a specified distance, they move away from each other and in the opposite direction to the movement of the packaging material 16 to reach the reference position.

The drive mechanism for moving the upper top sealer 31 and the lower top sealer 32 on a predetermined trajectory is, for example, configured as follows. The upper top sealer 31 is fixed to the lower surface of the upper sealer mounting base 33 and moves together with the upper sealer mounting base 33. The lower top sealer 32 is fixed to the upper surface of the lower sealer mounting base 34 and moves together with the lower sealer mounting base 34. Cam floors 36 are arranged on both sides of the upper sealer mounting base 33 and the lower sealer mounting base 34 so as to protrude outward. This cam floor 36 corresponds to a grooved cam provided on a cam plate 37 that is attached so as to be rotatably supported by a bearing on the inner surface of a machine frame 35 that has a basic structure of an approximately square shape that surrounds the periphery of the packaging material 16, and moves on the above-mentioned predetermined trajectory according to the shape of the grooved cam.

The cam plate 37 is connected to one end of a rotating shaft 38. The other end of the rotating shaft 38 protrudes outside the machine frame 35 and is connected to a synchronous gear 39. The synchronous gears 39 connected to the upper and lower rotating shafts 38 mesh with each other and can rotate synchronously, and rotate by receiving the rotational force of the drive motor 40. Therefore, when the drive motor 40 rotates, each cam plate 37 rotates in a predetermined direction, and the upper top sealer 31 and the lower top sealer 32 move using the cam mechanism as described above. Note that the configuration for rotating using the cam mechanism is conventionally known, so a detailed description thereof will be omitted. Also, instead of using a cam in this way, multiple drive motors such as a drive motor for moving the upper top sealer 31 and the lower top sealer 32 up and down and a drive motor for moving them forward and backward may be provided, and the upper top sealer 31 and the lower top sealer 32 may be moved in revolution by operating each drive motor at an appropriate timing, and various configurations can be taken.

A through hole 322 is provided on the center line extending in the width direction at the center of the lower top sealer 32 in the conveying direction, and the top cutter 41 is arranged in the through hole 322 so that it can move up and down. The top cutter 41 has a blade 411 formed at the upper end. The top cutter 41 moves up and down relative to the upper top sealer 31 by receiving force from an air cylinder 42 as a driving source attached to the lower surface of the lower sealer mounting base 34. More specifically, the lower end of the top cutter 41 is fixed to a connecting plate 43 and is connected to the air cylinder 42 via the connecting plate 43. When the top cutter 41 descends to the standby position, the blade 411 is located below the sealing surface 321 and is stored in the lower top sealer 32, and when the top cutter 41 ascends to the operating position, the blade 411 is located above the sealing surface 321 and protrudes outside the sealing surface 321.

Meanwhile, a narrow groove 312 is formed on the center line of the upper top sealer 31 at a position opposite the top cutter 41. As a result, when the packaging material 16 is sandwiched from above and below and heat-sealed between the upper top sealer 31 and the lower top sealer 32, the air cylinder 42 is activated and the top cutter 41, which is in the standby position, moves upward, and the blade portion 411 protruding upward from the sealing surface 321 enters the groove 312 provided in the upper top sealer 31. As a result, the packaging material 16 is cut horizontally along the blade portion 411.

In this embodiment, each sealing surface 311, 321 is a seal for forming a vertical seal in the top seal portion of the package 29 formed by the top sealing device 30. That is, as shown in enlarged views in Figs. 2(b) and (c), the sealing surfaces 311, 321 have a layout in which convex portions 45 and concave portions 46 formed to extend along the conveying direction are alternately arranged in a direction perpendicular to the conveying direction. The convex portion 45 formed on the sealing surface 311 of the upper top sealer 31 faces the concave portion 46 formed on the sealing surface 321 of the lower top sealer 32, and the concave portion 46 formed on the sealing surface 311 of the upper top sealer 31 faces the convex portion 45 formed on the sealing surface 321 of the lower top sealer 32, and the dimensions and shapes of the convex portions 45 and the concave portions 46 are made to fit together. As a result, when the upper top sealer 31 and the lower top sealer 32 move closer to each other by the drive mechanism described above and the sealing surfaces 311, 321 of each other sandwich the packaging material 16, the respective convex portions 45 enter and join the opposing concave portions 46, and the sandwiched packaging material 16 deforms to conform to the shapes of the convex portions 45 and concave portions 46. Then, when heated and pressurized in this state, it is sealed in that shape, and a wavy vertical seal portion is formed in which concave and convex portions extending from the main body side of the package 29 toward the tip of the top seal portion are alternately repeated in the width direction.

Furthermore, in this embodiment, the recess 46 and the protrusion 45 are approximately trapezoidal. The protrusion 45 is tapered, with the tip side being a flat portion 451 corresponding to the upper base (<lower base) which is the short base of the trapezoid, and the oblique side portions 452 which are the legs of the trapezoid are arranged on both sides of the flat portion 451. The recess 46 has an approximately trapezoidal inner shape in the recessed portion, with the back side being a flat portion 461 corresponding to the upper base (<lower base) which is the short base of the trapezoid, and the oblique side portions 462 which are the legs of the trapezoid are arranged on both sides of the flat portion 461. As described above, the protrusions 45 and the recesses 46 are arranged alternately, so that the oblique side portions 452 of the adjacent protrusions 45 and the oblique side portions 462 of the recesses 46 are in the same position.

The unevenness for forming the vertical seal is thus made approximately trapezoidal, with the peaks and valleys being flat sections 451, 461, so that the packaging material 16 sandwiched between the upper top sealer 31 and the lower top sealer 32 is positioned along the flat sections 451, 461, even if it is made of a material that does not stretch easily, such as paper (see Figures 3(a)->(b)). Therefore, the packaging material 16 is in contact with the sealing surfaces 311, 321 with almost no gaps. As a result, the packaging material 16 is firmly sandwiched between the peaks and valleys of the sealing surfaces 311, 321, and the entire packaging material, including the area around the center seal where the thickness of the packaging material is thick, is firmly heated and neatly sealed.

When a packaging material is sandwiched between a conventional top sealer with a sealing surface that has triangular wave-like irregularities, the pointed peaks on the sealing surface alternately press the packaging material against the other material from above and below. However, if the packaging material does not stretch easily, it will not be able to conform to the uneven shape and a space will form between the sealing surface and the packaging material. This space will then act as an insulating layer, preventing the heat from the sealing surface of the top sealer from being efficiently transferred to the packaging material, resulting in poor sealing or insufficient sealing. This embodiment can prevent such a situation from occurring.

On the other hand, the blade portion 411 on the tip side of the top cutter 41 is formed in a roughly triangular wave shape, and the arrangement pitch t1 of the vertices of each triangle is set to an integer multiple of the arrangement pitch t2 of the unevenness of the seal mesh formed on the sealing surface 321 of the lower top sealer 32 on which the top cutter 41 is mounted. In this embodiment, since the tip side of the convex portion 45 and the rear side of the concave portion 46 are both flat portions 451, 461, the arrangement pitch t2 may be set to the interval between predetermined positions (e.g., centers, etc.) of adjacent flat portions 451, for example. The value of the integer multiple may be 1x (same interval), but in this embodiment it is set to 2x.

Furthermore, in this embodiment, each cutting edge of the blade portion 411 of the top cutter 41, i.e., the apex of each approximately triangle, is configured to be located at the installation position of the flat portion 451 of the convex portion 45 formed on the sealing surface 321 of the lower top sealer 32 when viewed in the conveying direction of the packaging material.

With this configuration, the packaging material 16 sandwiched between the upper top sealer 31 and the lower top sealer 32 is deformed to match the unevenness of the sealing surfaces 311, 321, and in this state, each apex of the blade tip of the blade portion 411 of the top cutter 41 in the standby position of the lower top sealer 32 faces the flat portion 161 of the packaging material 16 that has been deformed into a convex shape (see FIG. 3(b)). Then, when the top cutter 41 moves upward while the packaging material 16 is sandwiched between the upper top sealer 31 and the lower top sealer 32, the blade tip of the blade portion 411 comes into contact with the flat portion 161 of the opposing packaging material 16 (see FIG. 3(c)), and when the top cutter 41 rises further and the blade portion 411 protrudes above the sealing surface 321 (see FIG. 3(d)), the blade tip cuts the convex portion (mountain portion) of the packaging material 16 in a manner that pushes it up, resulting in a sharper cut. At this time, the blade tips of the triangles that make up the blade portion 411 come into contact with the respective flat portions 161 at the same time and push up and cut at the same time, so that an even force is applied to the packaging material 16. Therefore, these effects work synergistically, resulting in a cleaner cut.

In the above embodiment, the blade tips of the blade portion 411 of the top cutter 41, i.e., the apex of each approximate triangle, are configured to be located at the installation position of the flat portion 451 of the convex portion 45 formed on the sealing surface 321 of the lower top sealer 32 when viewed in the transport direction of the packaging material. However, more preferably, the shape of each triangle constituting the blade portion 411 is an isosceles triangle (including an equilateral triangle) with the blade tip as the apex, aligned with the center portion of the flat portion 451. In this way, cutting starts from the center portion of the flat portion 161 of the packaging material 16, and transitions to cutting the hypotenuse portions 162 of the ridge line located on both sides of the flat portion 161 at the same time, resulting in a cleaner cut.

In the above embodiment, each cutting edge of the blade 411 of the top cutter 41, i.e., the apex of each approximate triangle, is configured to be located at the installation position of the flat portion 451 of the convex portion 45 formed on the sealing surface 321 of the lower top sealer 32 when viewed in the transport direction of the packaging material, but the present invention is not limited to this, and the cutting edges can be aligned in various locations, such as the installation position of the flat portion 461 of the concave portion 46 formed on the sealing surface 321 of the lower top sealer 32, or the installation position of the oblique portion 462. In either case, since the arrangement pitch t1 and the arrangement pitch t2 are in an integer multiple relationship, each cutting edge of the top cutter 41 contacts and cuts into the packaging material 16 at the same time, allowing for a clean cut.

In particular, by forming the convex and concave portions into a roughly trapezoidal shape and providing flat portions as in this embodiment, the packaging material 16 comes into contact with the sealing surfaces 311, 321 with almost no gaps as described above. As a result, the cutting edges of the top cutter 41 come into contact with predetermined portions while the packaging material 16 is firmly pinched and gripped in the peaks and valleys of the sealing surfaces 311, 321, so that the first contact portion can be cut cleanly no matter where it is located. However, it is preferable to align it with the flat portions 451, 461.

In addition, in the above embodiment, an example was described in which the top cutter 41 was built into the lower top sealer 32, but the present invention is not limited to this, and the top cutter 41 may also be built into the upper top sealer 31.

In the above embodiment, the top seal device used in a pillow packaging machine has been described, but the present invention is not limited to this and can be applied to the top seal devices of various packaging machines, such as a horizontal three-sided packaging machine that folds one packaging material from the center, stacks it on top of the other and side-seals the leading edges, or a four-sided seal packaging machine that stacks two packaging materials together. Furthermore, the present invention is not limited to being applied to horizontal packaging machines that transport packaging materials horizontally, but may also be applied to vertical packaging machines that transport packaging materials vertically.

In addition, in the above-described embodiment, the uneven shape of the seal mesh is approximately trapezoidal, but the present invention is not limited to this, and various shapes may be used, such as an approximately triangular shape with rounded apexes, or a smooth uneven shape like a wave in which arcs with relatively small amplitude are arranged alternately above and below.

Although various aspects of the present invention have been described above using embodiments, it should be noted that these embodiments and descriptions are not intended to limit the scope of the present invention, but are provided to aid in the understanding of the present invention. The scope of the present invention is not limited to the configurations and manufacturing methods explicitly described in the specification, but includes combinations of the various aspects of the present invention disclosed herein. Although the configurations of the present invention that are sought to be patented are specified in the appended claims, it is hereby reiterated that configurations disclosed in this specification that are not currently specified in the claims may be claimed in the future.

13: Product 16: Packaging material 161: Flat portion 162: Oblique portion 30: Top sealing device 31: Upper top sealer 311: Sealing surface 32: Lower top sealer 321: Sealing surface 41: Top cutter 411: Blade portion 45: Convex portion 451: Flat portion 452: Oblique portion 46: Concave portion 461: Flat portion 462: Oblique portion

Claims (2)

A top seal device that seals and cuts a packaging material containing a product in a direction perpendicular to the conveying direction of the packaging material,
a first top sealer and a second top sealer disposed to sandwich the packaging material;
a top cutter mounted so as to be capable of appearing and disappearing from a sealing surface at the tip of the first top sealer;
Equipped with
a sealing surface of the first top sealer, the sealing surface being provided with first convex portions extending in the conveying direction and first concave portions extending in the conveying direction, the first convex portions being alternately provided in a direction intersecting the conveying direction;
a sealing surface of the second top sealer, the sealing surface being provided with second convex portions extending in the conveying direction and second concave portions extending in the conveying direction, the second convex portions being alternately provided in a direction intersecting the conveying direction;
When the first top sealer and the second top sealer sandwich the packaging material, the first convex portion and the second concave portion face each other, and the first concave portion and the second convex portion face each other,
The first convex portion and the second convex portion each have a flat portion at a tip side thereof,
The first recess and the second recess each have a flat portion at the rear side thereof,
A top seal device in which a number of tapered blade portions are arranged at a predetermined pitch in a direction intersecting the conveying direction on the tip side of the top cutter, the pitch being an integer multiple of the arrangement pitch of the first convex portions or the first concave portions. The top seal device according to claim 1, wherein each cutting edge of the blade portion is configured to match the formation position of the first protrusion in the direction along the conveying direction.

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