JP2003011230A - Center sealing device and automatic packaging machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a center sealing device incorporated in an automatic packaging machine capable of performing center sealing certainly annd beautifully. SOLUTION: The center sealing device is equipped with a center sealing device main body 30 for holding the film superposed end 22 of a cylindrical film 15 to heat-seal the same and a preheater 31 arranged on the upstream side of the center sealing device main body to preheat a region to be heat-sealed by the center sealing device main body. The preheater directly heats the inside adhesive surface of the film superposed end and, concretely, hot air ejected from a hot air machine 41 is supplied to the space between a pair of the inclined plates 44 of an upper plate fixing nozzle 40 and ejected outwardly from the through-holes 44a of the inclined plates to be applied to the film region (inside adhesive surface) opposed to the inclined plates to heat the same.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a center seal device installed in an automatic packaging machine and an automatic packaging machine.

[0002]

2. Description of the Related Art As is well known, a pillow packaging machine uses a bag-making machine to form a continuous strip-shaped film into a tubular shape. As a result, both side edges of the band-shaped film are polymerized, and the polymerized ends are sealed by the center seal device to form a tubular film. On the other hand, since the articles to be packaged are sequentially supplied at a constant interval in the bag making machine, the articles to be packaged are also included in the tubular film at predetermined intervals, and the tubular film and the articles to be packaged in that state. Will be transported. Further, an end seal device is installed on the downstream side of the center seal device, and a predetermined position of the tubular film is sealed laterally in the traveling direction and cut to manufacture a pillow package in which the object to be packaged is sealed. It has become.

A center seal device for sealing the superposed ends of a film usually comprises at least one set of heating rollers. The heating roller sandwiches the overlapped end from both sides thereof with a predetermined pressure, and rotates in this state. At this time, the heating roller heats the film portion which is in contact with the heating roller under pressure, for example, by a built-in heater. This allows
The portion of the film that comes into contact with the heating roller is softened and further melted by being heated, so that the contact surfaces of the film polymerization ends are joined together.

After that, when passing through the heating roller, the heated and melted film portion is cooled (natural cooling or forced cooling), the above-mentioned bonding at the film polymerization end is completed, and the film is bonded (sealed).

[0005]

However, the above-mentioned conventional device has the following problems. That is, while the pair of heating rollers are in contact with the outer surface of the film superposition end, what is actually bonded is the inner surface (contact surface) of the film superposition end. Therefore, the heat from the heating roller is transferred from the outer surface to the inner surface of the film overlapping end with which the heating roller contacts. Therefore, as a matter of course, the temperature becomes higher on the outer surface of the film polymerization end.

As a result, in the case of a single film, for example, if the temperature is such that the inner surface can be bonded, the outer surface becomes even hotter, and the surface of the film becomes sticky, resulting in poor sealing. Further, the outer surface of the film is also melted and softened, and thus the appearance is deteriorated. further,
In the case of a thick film, it is difficult to transfer heat, so it is not possible to use a film material having a certain thickness or more.

The present invention has been made in view of the above background, and an object of the present invention is to provide a center seal device and an automatic packaging machine capable of reliably and cleanly performing center seal.

[0008]

In order to achieve the above-mentioned object, the center seal device according to the present invention has a means for forming a continuously drawn strip film into a tubular shape, and a means for forming the tubular film. A center seal device that seals the overlapping end of the tubular film, and a center seal device disposed downstream of the center seal device that seals in the width direction of the tubular film.
The center seal device used in an automatic packaging machine having an end seal device for making a cut, the seal device body sandwiching the polymerized end and heat-sealing, and arranged on the upstream side of the seal device body, A preheating device that preheats a portion to be heat sealed by the sealing device body is provided,
The preheating device is configured to directly heat the inner contact surface of the stacking end.

The preheating device can have various configurations. For example, the preheating device can include a device for injecting hot air and can inject the hot air to the inner contact surface. In this case, it is preferable that the device for injecting the hot air is arranged so as to be able to move up and down.

According to the present invention, since the preheating device directly heats the inner bonding surface of the polymerized end of the tubular film to be finally bonded, the polymerized end after passing through the preheating device is the outer surface of the film. The inner surface becomes hotter than the inner surface. Therefore, when the sealing device main body located on the downstream side pressurizes the preheated overlapping end portion and heats it for heat sealing, it is surely adhered even if the heating temperature is lowered, and the adhesion is also improved. To do.

Since the heating temperature in the main body of the sealing device can be lowered, the outer surface does not become sticky even if it is a single film, and reliable sealing can be performed. Further, even if the film is thick, the inner surface of the film is preliminarily warmed, so that sealing is possible. Further, since heating is performed at a relatively low temperature, the outer surface of the center-sealed portion is not melted and the aesthetic appearance is improved.

Further, the preheating device is provided with a fixed nozzle composed of an inclined plate having a through hole inserted and arranged in the overlapping end, and the hot air is passed through the through hole to an inner contact surface of the overlapping end. It is good to be jetted. This is preferable because hot air can be more reliably jetted to the inner surface of the film.

Although the seal device main body corresponds to the center seal device main body 30 in the embodiment and is a rotary sealer, it may be a bar sealer. Further, although the hot air is used as the preheating device in the embodiment, it may be preheated directly by a heater, as long as it can directly heat the inner contact surface of the superposition end of the tubular film. .

In the automatic packaging machine according to the present invention, by providing the center seal device having each of the above-mentioned configurations, the center seal portion of the manufactured package is more surely and cleanly heat-sealed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows a preferred embodiment of the present invention. In this embodiment, an example applied to a pillow packaging machine is shown. As shown in the figure, the strip film 1
1 is continuously withdrawn from the original roll 12 through a number of tension rollers 13 and guided to the bag making machine 14. Then, by passing through the bag making device 14, the strip-shaped film 11 is formed into a tubular shape and becomes the tubular film 15.

On the other hand, a supply conveyor 16 is disposed behind (upstream) in the traveling direction of the bag making machine 14, and the supply conveyor 16 is arranged so that its carry-out end is located near the entrance of the bag making machine 14. Has been done. The supply conveyor 16 includes an endless chain 18 provided between a pair of sprockets 17 and 17 ', and fingers 19 arranged at predetermined intervals of the endless chain 18. Then, the objects to be packaged 20 are pushed by the fingers 19, and the objects to be packaged 20 are sequentially transferred into the tubular film 15 at predetermined intervals.

Further, the article to be packaged 20 pushed by the fingers 19 moves together with the tubular film 15 and is heated by the center seal device 21 arranged at the next stage of the bag making machine 14, and is being transferred. The film superposition end 22 of the tubular film 15 is heat-sealed to provide a center seal.

The center-sealed tubular film 15 is further advanced and is endowed by an end-seal device 24 disposed in the next stage to be laterally cut in the direction of travel to produce a package 25. It is supposed to be done. The package 25 is unloaded by the unloading conveyor 26.

Here, in the present invention, as shown in FIG.
The center seal device 21 is the center seal device body 3
0, and a preheating device 31 installed on the upstream side of the center seal device body 30. Further, a pair of pinch rollers 27 are arranged on the upstream side and the downstream side of the center seal device 21, respectively.
At 7, the conveying force is applied to the film superposition end 22 of the tubular film 15.

The center seal device main body 30 is provided with a large-diameter disk-shaped heating roller 32 having a built-in heater, and a small-diameter disk-shaped auxiliary roller 33 that can contact the side surface of the heating roller 32. Two auxiliary rollers 33 are installed along the traveling direction of the tubular film 15. Thereby, between the two auxiliary rollers 33 and the heating roller 32,
The film superposition end 22 of the tubular film 15 is sandwiched by a predetermined pressure and heated. In addition,
The positions of the two auxiliary rollers 33 are adjusted so as to come into contact with the same film portion, and the two auxiliary rollers 33 are heated and pressed twice with a certain time from a predetermined portion of the film superposition end 22 to ensure the reliability. I am trying to seal it.

As shown in FIG. 2 and FIG. 3, the preheating device 31 jets hot air (warm air) to the inner surface of the film stacking end 22, that is, the adhesive surfaces on both side edges of the tubular film 15. The inner surface (adhesive surface) is heated. The specific configuration for realizing such functions is the tip (upper end).
Is disposed in the film stacking end 22 and the tubular film 15
Upper plate fixing nozzle 40 that separates both side edges (which become the film stacking end 22) of each other, a hot air blower 41 that is vertically movable below the upper plate fixing nozzle 40, and the hot air blower 4 thereof.
A cylinder 42 for moving up and down 1 is provided.

The upper plate fixing nozzle 40 is connected at the upper end,
2 arranged so that they move away from each other as they go downward
The inclined plate 44 is provided, and the inclined plate 44 has a large number of through holes 44a. Then, the upper plate fixing nozzle 4
0 is connected via a connecting plate 29 to the lower surface of the transport path (plate) 28 through which the tubular film 15 containing the article to be packaged 20 is transported.

The two inclined plates 44 may be formed by bending the central portion of one flat plate or may be formed by connecting the upper ends of the two inclined plates 44 prepared respectively. Furthermore, although the upper end is closed in this embodiment, a part of the upper end may be opened. Furthermore, all of the upper ends may be opened without connecting the two inclined plates 44 respectively prepared.

However, as will be described later, two inclined plates 44
Since the hot air jetted from the hot air blower 41 is supplied into the space between them, the hot air is guided to the outside of the upper plate fixing nozzle 40 from the through hole 44a, and the film portion facing the inclined plate 44, that is, Hot air hits the inner surface of the film superposition end 22 and is directly heated. Therefore, if the top is closed,
The hot air blown upward is bent in the course at the upper end of the inclined plate 44 and is smoothly guided to the outside from the through hole 44a of the inclined plate 44, which is preferable. Furthermore, it is more preferable to close the front and back for the same reason.

The hot air blower 41 is equipped with a flat nozzle 45 at its upper end outlet. This flat nozzle 45
Has a slit-shaped (slender strip-shaped) opening,
The opening is made to face the upper plate fixing nozzle 40. That is, the direction in which the opening extends and the transport direction of the tubular film 15 are arranged in parallel.

The hot air blower 41 is connected to a blower 47 via a hose 46. As a result, the air sent from the blower 47 reaches the hot air blower 41 via the hose 46, is heated to a predetermined temperature there, becomes hot air, and is jetted from the flat nozzle 45. A temperature sensor is installed in the hot air blower 41, and the temperature of the hot air blown by the temperature sensor is controlled to a desired value.

Further, the tip of the cylinder rod 42a of the cylinder 42 is connected to the bottom surface of the hot air blower 41, and the position of the hot air blower 41 and by extension, the upper end outlet of the flat nozzle 45 can be adjusted by expanding and contracting the cylinder 42. Like Specifically, during operation, the cylinder rod 42a of the cylinder 42 extends as shown in FIG.
Is positioned in the upper plate fixing nozzle 40. As a result, the hot air jetted from the flat nozzle 45 is efficiently supplied into the space between the pair of inclined plates 44 of the upper plate fixing nozzle 40, and the course of the hot air is changed to the outside from the through hole 44 a of the inclined plate 44. Is jetted.

On the other hand, when not in operation, the cylinder 42 contracts and the tip of the cylinder rod 42a and thus the flat nozzle 4
5 moves down. As a result, the upper end of the flat nozzle 45 stands by below the upper plate fixing nozzle 44.

According to this embodiment, the film overlapping end 22 in which both side edges of the tubular film 15 formed into a tubular shape by passing through the bag making device 14 are overlapped with each other is pinched by the pinch roller 27 and conveyed. Receive power. As a result, the article to be packaged 20 is conveyed in the tubular film 15 while being enclosed therein at a predetermined interval. This point is as described above.

During the transportation, the film superposition end 22 is
By inserting the upper plate fixing nozzle 40 on the inner surface (inner contact surface), the lower end side spreads left and right. At this time, the hot air blown from the hot air blower 41 is discharged from the flat nozzle 45 and supplied into the upper plate fixing nozzle 40. Then, the hot air is blown from the through hole 44a formed in the inclined plate 44 of the upper plate fixing nozzle 40. Therefore, the blown hot air hits the inner surface of the film stacking end 22 facing the inclined plate 44 of the upper plate fixing nozzle 40, heats the portion, and is preheated.

As described above, the film superimposing end 22 in which the inner surface of the film is directly heated further advances as it is, and is heated and pressed by the center seal device main body 30. Then, since the contact surface of the heated / pressurized portion is preheated by the preheating device 31, the center seal device main body 30 is reliably heat-sealed without heating at a high temperature.

[0032]

As described above, in the center seal device and the automatic wrapping machine according to the present invention, the inner bonding surface of the film polymerization part is directly preheated, and then the preheated portion is heated by the seal device main body. Since the center seal is applied under pressure, the center seal can be surely and neatly performed.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a pillow packaging machine to which a center seal device according to the present invention is applied.

FIG. 2 is a perspective view showing a preferred embodiment of a center seal device according to the present invention.

FIG. 3 is a front view thereof.

[Explanation of symbols]

11 Strip film 12 Raw roll 13 Tension roller 14 bag making machine 15 tubular film 16 Supply conveyor 20 Items to be packaged 21 Center seal device 22 Film edge 24 End seal device 25 packaging 27 pinch rollers 28 Transport path (plate) 29 Connection plate 30 Center seal device body 31 Preheating device 32 heating roller 33 Auxiliary roller 40 Upper plate fixed nozzle 41 hot air blower 42 cylinders 42a Cylinder rod 44 inclined plate 44a through hole 45 flat nozzle 46 hose 47 blower

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3E050 AA02 AB02 AB08 BA06 CA01                       CA06 CA08 CB01 CC07 DC02                       DD04 DD07 FA02 FB02 FB07                       GA10 GB05 HB03                 4F211 AD05 AD08 AH54 TA02 TC10                       TC17 TD11 TH06 TJ11 TN09                       TN15 TN24 TQ03 TQ06

Claims (5)

[Claims] 1. A means for forming a continuously drawn strip-shaped film into a tubular shape, a center seal device for sealing the overlapping end of the tubular film formed in the tubular shape, and a downstream side of the center seal device. Which is used in an automatic packaging machine having an end sealing device for sealing and cutting in the width direction of the tubular film, the sealing device sandwiching the polymerized end and performing heat sealing. A main body and a preheating device that is disposed on the upstream side of the sealing device main body and preheats a portion to be heat-sealed by the sealing device main body, and the preheating device directly heats an inner contact surface of the polymerization end. A center seal device characterized in that 2. The center seal device according to claim 1, wherein the preheating device includes a device for injecting hot air, and is configured to inject the hot air to the inner contact surface. 3. The center seal device according to claim 2, wherein the device for injecting the hot air is arranged so as to be vertically movable. 4. The preheating device includes a fixed nozzle including an inclined plate having a through hole inserted and arranged in the overlapping end, and the hot air is applied to an inner contact surface of the overlapping end through the through hole. The center seal device according to claim 2 or 3, wherein the center seal device is sprayed. 5. A means for forming a continuous strip-shaped film into a tubular shape, a center seal device for sealing a superposed end of the tubular film formed in the tubular shape, and a downstream side of the center seal device. 5. An automatic wrapping machine provided with an end seal device for sealing and cutting in the width direction of the tubular film, wherein the center seal device is any one of claims 1 to 4.
An automatic packaging machine having the configuration described in the item.