JPH0811576B2 - Sealing device for packaging machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device for heat-sealing a polymerized edge of a tubular packaging film made of a thermoplastic synthetic resin.

[0002]

2. Description of the Related Art Conventionally, in a bag-making filling and packaging machine or the like, as a sealing device for longitudinally sealing a polymerization edge along a feeding direction of a packaging film made of a thermoplastic synthetic resin, for example, Japanese Utility Model Publication No. 55-117902. There are techniques disclosed in. This sealing device is opposed to the downstream side of a pair of feed rollers for sandwiching the overlapping edge portion of the film and feeding the film to the downstream side, with a predetermined gap on both sides sandwiching the overlapping edge portion. An auxiliary heating device including a pair of heating blocks arranged is provided. Further, on the downstream side of the auxiliary heating device, a pair of seal rollers are rotatably arranged to sandwich the overlapping edge portion of the film to heat seal the film and to feed the film to the downstream side. That is, after the polymerization edge of the film is heated to a predetermined temperature in advance by the auxiliary heating device, the polymerization edge is heat-sealed by the seal roller, so that the film is formed even when the packaging machine is operated at a relatively high speed. A good seal can be applied to the.

[0003]

However, in the above-mentioned sealing device provided with the auxiliary heating device, not only a heating source is required for both the heating device and the sealing roller arranged downstream thereof, but also At the time of high-speed feeding of the film in the high-speed operation of the packaging machine (when the packaging length is large), depending on the material of the film used, it is necessary to set the temperature of the seal roller to be significantly higher than the melting point of the film. Since the film is heated at a high temperature, there is a drawback in that a packaging bag having a poor-looking seal portion in which "wrinkles" are generated is produced.

Further, in the above-mentioned packaging machine, when the supply of the article to be packaged is out of stock, the control is generally performed to temporarily stop the feeding of the film to prevent the occurrence of "empty bag". .
In this case, since the contact between the sealing roller of the sealing device and the film is a linear contact, it is necessary to set the sealing temperature of the roller to a high value. Open the seal roller of
It was necessary to prevent the film from melting (by separating it from the polymerized edge portion of the film). However, during high-speed operation in which the film stop time for preventing "empty bag" is less than 1 second, the opening / closing operation of the seal roller cannot be responded, and the roller is closed (film superposition). It was still held). Therefore, there is a drawback that the film sandwiched by the seal rollers is melted, and a complicated work of discharging the defective package generated at this time out of the line after packaging is required.

When the packaging machine is operating at a high speed, for example, when the feeding of the film is stopped and the sealing roller is opened at the same time to prevent the empty bag described above, the drive mechanism in the packaging machine is not normally used for sealing. The film sometimes passes through the position where the seal roller is arranged, which has a drawback that an unsealed portion is generated. Further, since the roller is kept at a high temperature even while the seal roller is open, the radiation heat thereof affects the film, and there is a drawback that the film is "stitched". It is also pointed out that the overlapped edge portion that causes the "tightening" may deviate from the sandwiching range of the seal roller and the film may not be fed normally.

Further, in the packaging machine, depending on the material of the film used, the shape of the packaged object, and the like, the overlapping edge portion of the tubular film passing between the feed roller and the seal roller is moved in the feeding direction. On the other hand, it sometimes tilted up and down. In this case, it becomes impossible to preheat the entire planned sealing portion of the polymerization edge portion by the auxiliary heating device,
There is also a problem in that the seal width of the seal roller varies, and a product having a poor appearance is manufactured.

[0007]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned various drawbacks inherent in the above-mentioned sealing device, and has been proposed in order to solve the above-mentioned disadvantages. An object of the present invention is to provide a sealing device in which a packaging film is fed in a state of being held at a position and a sealing defect does not occur. Another object of the present invention is to provide a sealing device capable of performing sealing at a relatively low temperature by heating the film at a uniform temperature over a predetermined length. Further, even when the feeding of the packaging film is controlled to be temporarily stopped, a sealing device capable of reliably and excellently sealing the film and preventing the occurrence of an unsealed portion is provided. The purpose is to provide.

[0008]

[Means for Solving the Problems] Overcoming the above-mentioned problems,
In order to achieve the intended purpose, the present invention is a sealing device for sealing a polymerized edge portion extending in the feeding direction of a tubular film, wherein the polymerized edge portion of the tubular film is A pair of sealing means, which are disposed opposite to each other on both sides of the sandwiched body, for a predetermined length and which can discharge heated pressure air from the opposing surfaces, and a pair of sealing means disposed upstream and downstream of the sealing means. A pair of feed rollers that rotate in mutually opposite directions sandwiching the overlapping edge portion of the film and are tiltable in the film feeding direction; and a pair of feed rollers sandwiched by the pair of feed rollers. The sealing film is characterized in that the overlapping edges of the tubular film passing between the sealing means are sealed by blowing heated pressure air from the facing surfaces of both sealing means.

Another invention of the present application is a sealing device for sealing a superposed edge portion of a tubular film extending in a feeding direction, and sandwiching the superposed edge portion of the tubular film. A pair of seal blocks arranged opposite to each other for a predetermined length on both sides, and provided along substantially the entire length in the longitudinal direction along the overlapping edge portion of the seal block, and one end in the longitudinal direction thereof. A first passage communicating with a supply source of pressure air, a guide member inserted into the first passage, and defining a spiral passage between an outer surface of the first passage and an inner wall of the first passage; A first heating means that is inserted over the entire length of the member and that heats the pressurized air that moves through the spiral passage; and a first passage that is provided over substantially the entire length of the seal block in the longitudinal direction. Is opposite the end communicating with the source of pressure air A second passage communicating with an end portion, a plurality of air discharge holes formed in a seal block so as to communicate with the second passage, and opening on a sealing surface facing the other seal block, and the second passage being close to the second passage. Is arranged as
Second heating means extending substantially the entire length of the seal block in the longitudinal direction, and second heating means arranged upstream and downstream of the seal block and rotating in opposite directions with the superposed edge portion of the tubular film interposed therebetween. It is characterized by comprising a pair of feed rollers composed of a pair of feed rollers.

Still another invention of the present application is a sealing device for sealing a superposed edge portion of a tubular film extending in the feeding direction, wherein the superposed edge portion of the tubular film is A pair of seal blocks that face each other on both sides of the sandwich for a predetermined length so that they can move toward and away from each other, and that can discharge heated pressure air from the facing surfaces, the seal block, and the block connected to the block. And a means for stopping the supply of air when the supply of the cylindrical film is stopped, and the means for disposing the cylindrical film. A means for moving both seal blocks away from each other when the feeding is stopped for a set time or more, and means arranged in the upstream and the downstream of the seal blocks, which are opposite to each other with the overlapping edge portion of the tubular film interposed therebetween. Twice Characterized by being composed of a feed roller pair and comprising a pair of feed rollers to be.

[0011]

The overlapping edge portion of the film formed into a tubular shape by the bag-making device is fed to the downstream side by the two feed roller sets each including the pair of feed rollers sandwiching the edge portion. The overlapping end edge portion facing between the two pairs of feed rollers extends a predetermined length in the feeding direction of the end edge portion and passes between a pair of opposed seal means when passing between the pair of seal means. It is sealed by heating pressure air discharged from the facing surface. When the overlapped edge of the tubular film deviates in the direction of being pulled in or out of the nip portion of the feed roller, tilt each feed roller set in the required direction and feed the overlapped edge that passes through the sealing means. The delivery line is kept constant.

The overlapping edge portion of the film formed into a tubular shape by the bag-making device is fed to the downstream side by two feeding roller sets consisting of a pair of feeding rollers that sandwich the edge portion.
The overlapping end edge portion facing between the two pairs of feed rollers passes between a pair of opposing seal blocks extending a predetermined length in the feeding direction of the end edge portions. The pressure air supplied to the seal block is heated to a required temperature when moving in the spiral passage defined inside the block, and then the second passage through which a plurality of air discharge holes opened in the seal surface communicate with each other. Is supplied to. Then, the heating pressure air in the second passage is reheated by the second heating means and then discharged from the air discharge hole toward the overlapping edge portion, whereby the overlapping edge portion is heat-sealed. It

The overlapping edge portion of the film formed into a tubular shape by the bag-making device is fed to the downstream side by two feeding roller groups consisting of a pair of feeding rollers that sandwich the edge portion.
The overlapping edge portion facing between the two pairs of feed rollers is opposed to each other when extending between the pair of seal blocks facing each other by extending a predetermined length in the feeding direction of the edge portions. It is sealed by heating pressure air discharged from the surface. When the feeding of the tubular film is stopped for a short time, the discharge of the heating pressure air from the seal block is stopped.
Further, when the tubular film is stopped for a relatively long time, the discharge of the heating pressure air from the seal block is stopped and both seal blocks are separated from each other.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sealing device for a packaging machine according to the present invention will be described below with reference to the accompanying drawings with reference to preferred embodiments. In the embodiment, a horizontal bag-making filling and packaging machine will be described as an example of a packaging machine that employs a sealing device, but the present invention is not limited to this, and a vertical bag-making filling and packaging machine is also applicable. It can be applied.

FIG. 1 is a schematic perspective view of an essential part of the sealing device according to the embodiment in an exploded state.
0 is a pair of feed roller sets 16 and 16 including a pair of seal blocks 12 and 12 and a pair of feed rollers 14 and 14 disposed on the upstream side and the downstream side of the blocks 12 and 12 in the film feeding direction. It is basically composed of and.
Then, the tubular film 18 is fed by the pair of feed rollers 16, 16 and the pair of seal blocks 12, 1
A seal is applied to the overlapping end edge portion 18a in the longitudinal direction of the tubular film 18 passing between the two.

(Regarding Seal Block) The pair of seal blocks 12 and 12 are on both sides sandwiching the longitudinal overlapping edge portion 18a of the film 18 which is formed into a cylindrical shape by a bag making machine (not shown) and is transferred. Are arranged so as to face each other over a predetermined length, and the superposed edge portion 18a is sealed by heating pressure air discharged from the facing surface. Further, the seal blocks 12 and 12 are configured to be movable toward and away from each other by a moving means described later. In addition,
Since the structures of the seal blocks 12 and 12 arranged opposite to each other with the feeding path of the overlapping end portion 18a of the tubular film 18 interposed therebetween are the same, the structure of one seal block 12 will be described and the other will be described. The same members of the seal block 12 are designated by the same reference numerals, and the description thereof will be omitted.

At a portion of the seal block 12 which is separated from the other seal block 12, as shown in FIG. 1, both end portions are closed over substantially the entire length in the longitudinal direction (the extending direction of the overlapping edge portion 18a). The required first passage 20
Has been drilled. A supply source of pressure air (not shown) disposed outside is provided near one longitudinal end of the first passage 20.
A supply hole 22 communicated with and connected via a pipe body 23 communicates therewith, and a discharge hole 26 communicated with a second passage 24 described later is formed in the vicinity of the other end. Also the first
As shown in FIG. 2, an air supply stop control valve 27 including an electromagnetic valve or the like is disposed in the pipe body 23 that connects the passage 20 and the air supply source, and as described later, the cylindrical film 18 is supplied. When stopped, the supply of pressurized air to the seal block 12 can be stopped. Between the first passage 20 and the air supply source, a flow rate adjusting means and a pressure adjusting means (both not shown) such as a precision regulator are connected in series, and the first passage 20 has a flow rate of about 70 Nl /.
It is configured so that it can be appropriately adjusted so that a large flow rate of air of about 100 to 100 Nl / min is supplied.

In the first passage 20, as shown in FIG.
A guide member 28 formed in a spiral shape in which the diameter of the large-diameter portion matches the inner diameter of the first passage 20 is inserted, and the outer surface of the guide member 28 and the inner wall of the first passage 20 form a spiral passage. It is designed to be defined. A cartridge heater 30 is inserted in the center of the guide member 28 over its entire length so as to heat the guide member 28 to a predetermined temperature. That is, the pressure air supplied from the supply hole 22 to the one end of the first passage 20 is heated to a predetermined temperature while moving through the spiral passage, and then the discharge hole 26.
It is discharged to the second passage 24 via.

At a portion of the seal block 12 adjacent to the other seal block 12, as shown in FIG. 1, there is provided a second passage 24 of a required straight length whose both ends are closed over substantially the entire length in the longitudinal direction thereof. , Is provided in parallel with the first passage 20. A discharge hole 26 that communicates with the first passage 20 is communicated with one end of the second passage 24 in the longitudinal direction, and heating pressure air heated through the first passage 20 is supplied. . In addition, the seal block 12 intersects with the extending direction of the second passage 24, and
A plurality of air ejection holes 32 communicating with the above are formed in a required pattern. The air discharge hole 32 is formed on the seal surface 12 that faces the other seal block 12 facing the air discharge hole 32.
It is open to the a side. That is, the heated pressure air supplied to the second passage 24 is discharged from the sealing surface 12 a through each air discharge hole 32. The air discharge hole 3
As the drilling pattern of 2, for example, the seal block 1
The air ejection holes 32 are provided in three rows in the vertical direction along the longitudinal direction of 2, and the air ejection holes 32 in each row are formed in a staggered manner.

A cartridge heater 34, which is parallel to the passage 24, is disposed in the vicinity of the second passage 24 over the entire length of the seal block 12, and the heater 34 is supplied to the second passage 24. While heating the heated pressure air, the first passage 20 functions to prevent the temperature of the heated pressure air from decreasing. Further, a heat pipe 36 is arranged in parallel with the cartridge heater 34 at a position close to the air discharge hole 32 so that the seal block 12 heated by the cartridge heater 34 has a uniform temperature distribution in the longitudinal direction. There is. As a result, the heating pressure air discharged from all the air discharge holes 32 formed in the seal block 12 can be made to have substantially the same temperature.

A temperature detecting means (not shown) such as a thermistor is arranged near the position where the cartridge heater 34 is arranged in the seal block 12, and the block 12 is set so that it can be maintained at a constant temperature. is there. Further, the cartridge heater 30 and the second heater disposed on the guide member 28.
Cartridge heater 34 disposed near the passage 24
For example, each having a capacity of about 350 W is used,
A capacity of 700 W is given to each seal block 12. With these configurations, for example, when the original pressure of the pressure air supplied to the seal block 12 is set to 5 kg / cm ² , the heating pressure air discharged from the seal block 12 is 70 Nl / min to 100 Nl / m.
Within the range of in, and the temperature thereof is within the range of 130 ° C. to 150 ° C., it can be changed according to various conditions such as the material of the film and the rotation speed of the packaging machine.

Here, the original pressure of the pressure air is 5 kg / cm.
Under the setting of ² , set the temperature of heating pressure air to 13
FIG. 7 shows the result of an experiment on the relationship between the flow rate and the temperature of the air actually discharged from the seal block 12 at 0 ° C. and 150 ° C. For example, the set temperature 130
When the temperature is set to ℃, the actual air temperature when supplying 70 Nl / min of pressure air is about 125 ℃, and 1
The actual air temperature when supplying pressurized air of 00 Nl / min was about 123 ° C. Also, set temperature 15
When the temperature is 0 ° C, the actual air temperature when supplying 70 Nl / min of pressurized air is about 143 ° C.
The actual air temperature when supplying 0 Nl / min of pressure air was about 140 ° C. As is clear from this experimental result, even when a large amount of air is discharged,
It was confirmed that the temperature drop of the heating pressure air discharged from the seal block 12 with respect to the set temperature was extremely small.

(Means for moving the seal block) The plate 3 arranged below the film feeding path of the packaging machine.
As shown in FIGS. 2 and 3, columns 40 are respectively provided at four corners of the column 8, and stays 42 are provided between the upper ends of the columns 40 and 40 facing each other in the direction intersecting the film feeding direction. A pair of support plates 44, 44 are disposed and fixed opposite to each other in the vicinity of both ends in the longitudinal direction (direction intersecting with the film feeding direction) of the stays 42, 42 which are spaced apart and parallel to each other in the film feeding direction. To be done. The support plates 44, 44 have a pair of guide rods 46, 44 spaced apart from each other in the film feeding direction by a predetermined distance.
46 are installed in parallel, and the guide rods 46, 46
Further, a pair of L-shaped holding bases 48, 48 are slidably arranged. Then, the seal blocks 12 are arranged and fixed on the upper surfaces of the respective holding tables 48.

An air cylinder 50 is arranged on the outer surface of each support plate 44, and the tip of a piston rod 50a extending inside the support plate 44 is connected to a position adjusting member 52 attached to the holding base 48. Has been done. Therefore, by energizing both air cylinders 50, 50 in the forward and reverse directions, the pair of seal blocks 12, 12 move toward and away from each other along the guide rods 46, 46 (see FIG. 6). The distance between the seal surfaces 12a and 12a of the two seal blocks 12 and 12 depends on the material and packaging conditions of the film so that the seal blocks 12 can be separated to a position where the radiant heat does not affect the film. Accordingly, the position adjusting member 52 can be appropriately adjusted.

(Regarding the Feeding Roller Set) As shown in FIG. 3, on the upstream side and the downstream side of the film feeding direction with the seal blocks 12 and 12 disposed therebetween, the overlapping edge portions of the tubular film 18 are formed. Two sets of feed rollers 16 and 16 composed of a pair of feed rollers 14 and 14 that rotate in mutually opposite directions with the 18a interposed therebetween are disposed. The two roller sets 16 and 16 direct the tubular film 18 toward the downstream side. Is configured to be transferred. Since both feed roller sets 16 and 16 have the same structure, the structure of the roller set 16 disposed on the upstream side will be described, and the same members of the feed roller set 16 on the downstream side are designated by the same reference numerals. The description is omitted.

As shown in FIG. 4, a bracket 56 is erected vertically on the frame 54 of the packaging machine facing the upstream side of the plate 38, and the upper end of a vertical portion 56a of the bracket 56 parallel to the film feeding direction. A through hole 56b is formed near the portion, and a long hole 56c elongated in the film feeding direction is formed below the through hole 56b. The mounting plate 62 is disposed and fixed via the bolts 58 and 58 and the nuts 60 and 60 which are inserted into the holes 56b and 56c.
Then, by loosening both bolts 58, 58, the mounting plate 62 is configured to swing in the required angle range in the film feeding direction with the upper bolt 58 as a fulcrum (see FIG. 5). Thereby, the pair of feed rollers 14 and 14 (described later) arranged on the mounting plate 62 can be inclined in the film feeding direction.

A housing 64 is horizontally extended and fixed to the mounting plate 62, and the drive-side feed roller 14 is provided on the vertical axis of the housing 64 at a position close to the mounting plate 62.
It is rotatably supported via (not shown). Further, a holding member 66 is fixed at a position separated from the mounting plate 62 of the housing 64, and a fulcrum boss 70 is integrally rotatably arranged on a horizontal shaft 68 rotatably supported by the holding member 66. . The feed roller 14 on the driven side is rotatably supported by the fulcrum boss 70 via a vertical shaft (not shown), and is sandwiched by the sandwiching portions 14a, 14a formed at the upper ends of the feed rollers 14, 14. , The overlapping edge portion 1 of the tubular film 18
It is configured to sandwich 8a.

The vertical shaft of the drive-side feed roller 14 disposed in the vicinity of the mounting plate 62 projects below the housing 64 and is connected to a drive means (not shown) at its end.
Two are connected. Further, the nip portion 14 of the feed roller 14
A gear 14b is integrally formed at the end opposite to the end where a is formed, and meshes with the gear 14b formed on the pair of driven rollers 14 on the driven side. Therefore, by rotating the vertical shaft in a predetermined direction by the driving means, the pair of feed rollers 14, 14 meshing with each other via the gears 14b, 14b rotate in mutually opposite directions, and the nipping portion 14
The overlapping edge portion 18a sandwiched between a and 14a is fed to the downstream side.

For example, when setting a film when changing the order, the horizontal shaft 68 pivotally supported by the holding member 66 is rotated to rotate the fulcrum boss 70 and the feed roller 14 on the driven side. By tilting, the sandwiching portion 14a is separated from the sandwiching portion 14a of the driving-side feed roller 14. Further, the driven-side feed roller 14 is always biased by a proper mechanism in a direction in which the driven-side feed roller 14 approaches the driven-side feed roller 14, and is set so as to sandwich the overlapping edge portion 18a of the tubular film 18 with a predetermined pressure. Has been done.

[0030]

Next, the operation of the sealing device according to the embodiment thus constructed will be described. A film 18 which is drawn from a film supply source and formed into a tubular shape by a bag-making device.
The overlapping edge portion 18a in the vertical direction is clamped by the feed rollers 14, 14 of each feed roller set 16 in the sealing device 10. In addition, the pair of seal blocks 12 and 12 arranged between the pair of feed rollers 16 and 16 has the overlapping edge portion 18
Positioning is performed in a state of being separated by a predetermined distance with a sandwiched therebetween (for example, about 3 mm). Further, the cartridge heaters 30 and 34 arranged in each seal block 12 are energized to heat the guide member 28 and the block 12 itself to a predetermined temperature.

The overlapping edge portion 18a of the tubular film 18
When sealing is applied to the seal block 12, the first passage 20 of each seal block 12 has 70 Nl / min to 100 Nl / min.
Supply pressurized air with a constant flow rate. The pressurized air moves along the spiral passage defined by the guide member 28 inserted in the first passage 20 while the guide member 28 is being guided.
Is heated to a predetermined temperature via. The heated pressure air is supplied to the second passage 24 through the discharge hole 26 communicating with one end of the first passage 20, as shown in FIG. The heated pressure air supplied along the second passage 24 over the entire length of the seal block 12 is discharged from the air discharge hole 32 communicating with the passage 24 and opening to the seal surface 12a. It should be noted that since the heating pressure air in the second passage 24 is reheated by the cartridge heater 34 arranged in the vicinity of the second passage 24, the temperature of the heating pressure air flowing through the inside of the seal block 12 is prevented from greatly decreasing. (See FIG. 7). Further, since the temperature distribution over the entire length of the seal block 12 is made uniform by the heat pipe 36, the temperatures of the heating pressure air discharged from all the air discharge holes 32 are substantially the same.

In this state, both seal blocks 12, 12 are
When the overlapped edge portion 18a passes between the seal surfaces 12a, 12a in FIG. 1, the overlapped edge portion 18a is heated and sealed by the pressure air heated from about 130 ° C. to 150 ° C. discharged from the seal block 12, 12. To be done. At this time, since the seal blocks 12, 12 extend over a predetermined length in the longitudinal direction of the overlapping edge portion 18a, the overlapping edge portion 18a passing through both blocks 12, 12 is sufficiently heated. In addition to being able to seal, a sufficient sealing strength can be obtained by using pressurized air having a large air flow rate. That is, even if the feeding speed of the tubular film 18 becomes high, the reliable and good sealing can be performed with the set temperature of the seal block 12 kept low.

(When the overlapped edge of the tubular film passing through the seal block is inclined) Depending on the material of the film used in the packaging machine, the shape of the packaged object, etc. The overlapping edge portion 18a of the tubular film 18 passing between the seal blocks 12, 12 is pulled downward from the holding portions 14a, 14a of the feed rollers 14, 14 or from the holding portions 14a, 14a. It may be pulled upward (see Fig. 5). Then, if the overlapped edge portion 18a is sealed in this state, a poor-looking product in which the seal width changes in the longitudinal direction is manufactured.
Therefore, in the embodiment, by constructing each of the feed roller groups 16 and 16 so as to be inclined in the film feeding direction,
Overlap edge portion 18a facing between the seal blocks 12 and 12
Are fed in parallel.

That is, first, the mounting plate 62 provided with the respective feed roller sets 16 is loosened by the two bolts 58, 58 for fixing the mounting plate 62 to the bracket 56, and the mounting plate 62 is used with the upper bolt 58 as a fulcrum. Be ready to tilt. Then, for example, the overlapping edge portion 18a is sandwiched between the feed rollers 14, 14 as shown by the chain double-dashed line in FIG. 5 (a).
When the sheet is fed in a direction away from the sheet and tilts upward toward the downstream side, the mounting plate 62 is tilted clockwise and the pair of feed rollers 14, 14 disposed on the mounting plate 62 are moved to the downstream side. Incline downwards. Next, both bolts 58,
The mounting plate 62 is positioned and fixed by tightening 58. In this state, the overlapping edge portion 18a fed by the pair of feed rollers 14 and 14 is applied with a force for moving it downward, and as a result, as shown by the solid line in FIG. The overlapping edges 18a passing between the blocks 12, 12 can be parallel.

Further, the overlapping edge portion 18a passing through the seal blocks 12, 12 is drawn in from the sandwiching portions 14a, 14a of the feed rollers 14, 14 as shown by the chain double-dashed line in FIG. 5 (b). When it is fed to the downstream side and tilts downward toward the downstream side, the mounting plate 62 is tilted counterclockwise, and the feed rollers 14, 14 of each feed roller set 16 are tilted upward toward the downstream side. . This allows both rollers 14,
The overlapping edge portion 18a fed by 14 is applied with a force for moving the overlapping edge portion 18a upward, and as a result, as shown by the solid line in FIG. It passes between the seal blocks 12, 12. In addition, when the feed rollers 14 and 14 are inclined downward toward the downstream side, the packaging film itself is pulled downward, so that a good packaging product in which the width direction of the filled packaged object is closely adhered to the packaging film is obtained. There are advantages to be obtained.

In the embodiment, the mounting plate 62 provided with the feed roller set 16 is tilted and positioned by loosening or tightening the bolts 58, 58. For example, the mounting plate 62 can be freely rotated on the bracket 56. Alternatively, the mounting plate 62 may be tilted by an appropriate driving means.

(When Empty Bag Prevention Control is Performed) Here, in the sealing apparatus according to the embodiment, the supply of the packaged product to the packaging machine is out of stock and the supply of the tubular film is stopped. Sometimes, depending on the number of missing items according to the packaging speed (that is, the time when the tubular film is stopped), the control of stopping the discharge of the heating pressure air and the discharging of the heating pressure air are performed, and the sealing block is It is configured to perform control so as to separate the overlapping edge portion to a position where the heat influence is small.

(When the number of missing items is small) For example, in a state where high-speed operation of 250 pieces / minute is performed by the horizontal bag-making filling and packaging machine (see FIG. 6 (a)), 1 to 3 pieces are continuously supplied. If a shortage occurs (the film feeding stop time at this time is within about 1 second), the air supply stop control valve 27 disposed in the pipe body 23 connecting the air supply source and the first passage 20.
Is operated to stop the supply of the compressed air to the seal blocks 12, 12. Since the seal temperature of the seal block 12 is set low, the discharge of the heating pressure air is stopped, so that both seal blocks 12, 12 are kept for a short time.
It is possible to prevent a thermal effect (melting) from being exerted on the polymerization edge portion 18a stopped during the period. Further, the switching of the valve can sufficiently cope with the stop and start of the tubular film 18 in a short time during the high speed operation.

(In the case of a large number of out-of-stock items) Further, in the above-described packaging machine operating at high speed, when the number of out-of-stock items in the package is three or more consecutively (the stop time of film feeding is about 1). Seconds or more), the seal block 12,1
The supply of the pressurized air to 2 is stopped, and at the same time, the air cylinders 50, 50 are urged in a predetermined direction to separate the both seal blocks 12, 12 from each other (see FIG. 6B). As a result, the overlapping edge portion 18a facing between the seal surfaces 12a, 12a is not affected by the radiant heat from the seal block itself. Therefore, even if the tubular film 18 is stopped to prevent empty bags, it is possible to effectively prevent the film from being heated and causing "stitching" or the like during that time.

However, when the stopping time of the tubular film 18 extends for a long time of, for example, 20 seconds or more, the packaging bag for the film present at that position is controlled to be discharged as a defective seal out of the line. The operation control relating to the stop time of the film is based on the conditions such as the material and thickness of the packaging film used, the stop of film feeding of the packaging machine and the deceleration to the stop at the start, or a predetermined period from the start. It can be appropriately selected according to the time required to reach the speed.

Further, since the sealing device 10 seals the overlapped edge portion 18a facing between the pair of seal blocks 12, 12 when the tubular film 18 is being fed, the tubular film 18 is When stopped, the film 1 with a seal between both seal blocks 12 and 12
8 is facing. Therefore, both seal blocks 12, 12
After the rollers are separated from each other, the tubular film 18 is attached to the double feed roller set 1
Even if it moves a little due to the inertia of 6 and 16, the unsealed portion does not occur.

[0042]

As described above, according to the sealing device for a packaging machine according to the present invention, a pair of sealing means are arranged opposite to each other with the overlapping edge portion of the film interposed therebetween, and heating is performed from the facing surfaces. Since the pressure air is ejected, it is possible to seal the film while passing the overlapping edge portion of the film between the both sealing means. That is, since it is possible to secure a sealing region for the length of the sealing means, it is possible to obtain sufficient sealing strength while setting the sealing temperature lower than that of the conventional sealing roller system, and it is possible to obtain a good appearance. A good seal is possible.

Further, since the feed roller group is constructed so as to be tiltable in the film feeding direction, the feeding line at the overlapping edge portion of the tubular film passing through the sealing means can be kept constant. Moreover, by tilting the downstream side of each feed roller set downward, the width of the tubular film can be narrowed down, and it is possible to wrap the film "tight" with respect to the object to be packaged. There is also.

Further, since the heating pressure air discharged from the sealing means can be kept at substantially the same temperature over the entire area in the longitudinal direction, efficient sealing can be performed. Further, since the pressure air heated by passing through the first passage is heated by the cartridge heater arranged in the region close to the air discharge hole, the temperature drop can be extremely reduced.

Further, it is possible to prevent the generation of an unsealed portion due to the stop of the film feeding and the excessive heating of the film, and it is possible to prevent the generation of a defective packaged product due to a defective sealing.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a main part of a sealing device according to an embodiment, which is disassembled and partially cut away.

FIG. 2 is a side view of the sealing device according to the embodiment.

FIG. 3 is a plan view of the sealing device according to the embodiment.

FIG. 4 is a schematic perspective view showing a feed roller group in the sealing device according to the embodiment.

FIG. 5 is an explanatory diagram showing a tilted state of a feed roller group.

FIG. 6 is an explanatory view showing the operation of the seal block in the sealing device.

FIG. 7 is a graph showing the relationship between the temperature of heating pressure air discharged from the seal block of the sealing device according to the embodiment and the set temperature with respect to the flow rate.

[Explanation of symbols]

 10 Sealing Device 12 Seal Block 12a Sealing Surface 14 Feed Roller 16 Feed Roller Set 18 Packaging Film 18a Polymerization Edge 20 First Passage 24 Second Passage 27 Air Supply Stop Control Valve 28 Guide Member 30 Cartridge Heater 32 Air Discharge Hole 34 Cartridge Heater 50 air cylinder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunihiko Ito 4-380, Nakaodai, Nishi-ku, Nagoya-shi, Aichi Fujikikai Co., Ltd. Nagoya Plant (72) Inventor Yasuo 4-380, Nakaodai, Nishi-ku, Nagoya-shi, Aichi Fuji Co., Ltd. Fujikikai Nagoya factory

Claims (3)

[Claims] 1. A sealing device for sealing a superposed edge portion extending in a feeding direction of a tubular film.
A pair of sealing means, which are disposed opposite to each other across a predetermined length on both sides of the overlapping edge portion of the tubular film, and from which the heating pressure air can be discharged, and the upstream of the sealing means. And a feed roller group that is disposed downstream and that rotates in opposite directions with the overlapping edge portion of the tubular film interposed therebetween and that can tilt in the film feeding direction. It is configured such that the superposed edge of the tubular film passing between the pair of sealing means in a state of being sandwiched by the feed roller group is sealed by blowing heated pressure air from the facing surfaces of both sealing means. A sealer for a packaging machine. 2. A sealing device for sealing a superposed edge portion extending in a feeding direction of a tubular film.
A pair of seal blocks that are arranged opposite to each other across a predetermined length on both sides of the overlapped edge portion of the tubular film, and substantially the entire length in the longitudinal direction along the overlapped edge portion of the seal block. A first passage, which is bored and communicates with a supply source of pressure air at one longitudinal end thereof, and is inserted into the first passage, and has a spiral shape between an outer surface of the first passage and an inner wall of the first passage. A guide member that defines a passage, a first heating unit that is inserted over the entire length of the guide member and that heats the pressurized air that moves in the spiral passage, and a substantially entire length of the seal block in the longitudinal direction. The first hole
A second passage communicating with an end opposite to the end communicating with the supply source of pressure air, and a seal block formed in the seal block so as to communicate with the second passage and facing the other seal block. A plurality of air discharge holes that are open in the surface, a second heating means that is disposed close to the second passage and that extends over substantially the entire length of the seal block in the longitudinal direction, and upstream and downstream of the seal block. And a feed roller group composed of a pair of feed rollers that rotate in opposite directions with the overlapping edge portion of the tubular film interposed therebetween. 3. A sealing device for sealing a superposed edge portion extending in a feeding direction of a tubular film.
A pair of seal blocks, which are opposed to each other across a predetermined length of the tubular film for a predetermined length and are arranged so as to be movable toward and away from each other, and capable of ejecting heated pressure air from the opposed surfaces. Related to the seal block, a unit that is disposed between the seal block and an air supply source connected to the block and that stops the air supply when the supply of the tubular film is stopped. Is installed in
When the feeding of the tubular film is stopped for a set time or longer,
A feed roller composed of a means for moving both seal blocks away from each other and a pair of feed rollers arranged upstream and downstream of the seal block and rotating in mutually opposite directions with the overlapping edge portion of the tubular film interposed therebetween. A sealing device for a packaging machine, characterized in that it is composed of a set.