JPH10101027A - Method and apparatus for sealing packaging film in vertical bag-making, filling and packaging machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extremely easily realize an appropriate lateral seal by applying to a vertical bag-making, filling and packaging machine. SOLUTION: A pair of lateral heater blocks 5, 6 are adjusted to hold a predetermined distance at the time of laterally sealing, and a packaging film is held and laterally sealed with the distance. If a predetermined gap is thus kept between the respective lateral heater blocks 5, 6 at the time of laterally sealing the packaging film, the packaging film may not be excessively pressed irrespective of a film sealing pressure at this time. In addition, the lateral heater blocks 5, 6 press the packaging film to a certain thickness with the above distance, whereby the packaging film can be reliably heat-welded and a lateral seal free from a sealing failure can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for sealing a packaging film in a vertical bag making and filling machine for horizontally sealing a supplied packaging film using a pair of horizontal heater blocks. .

[0002]

2. Description of the Related Art A vertical bag making and filling machine for forming a band-shaped packaging film into a bag shape and filling an object to be packaged therein is widely used in various industries including the food industry.

FIG. 8 is a perspective view showing a schematic structure of a vertical bag making and filling machine. The outline of the vertical bag-making filling and packaging machine will be described with reference to the drawing. The belt-shaped packaging film 100 unwound from the winding drum 1 is wound around the outer peripheral surface of a cylindrical forming tube 2 while the unwinding belt 3 is wound. To be transported downward. A vertical sealing heater 4 is provided on the side of the forming tube 2 so as to be opposed thereto, and the overlapping side end 100a of the packaging file 100 wound around the forming tube 2 is thermally fused by the vertical sealing heater 4 (vertical sealing). Then, the packaging film 100 is formed into a cylindrical shape.

Further, a pair of horizontal heater blocks 5 and 6 are provided at predetermined positions below the forming tube 2 so as to be opposed to each other with the transport path of the packaging film therebetween, and the packaging is fed downward by a feeding belt. The film is sandwiched between the horizontal heater blocks 5 and 6, and is heat-sealed (horizontal seal) to form a bag.

[0005] Thereafter, the inside of the packaging film conveyed further downward is filled with an article to be packaged through the hollow portion of the forming tube 2, and the upper end is again heat-sealed (horizontally) by the horizontal heater blocks 5 and 6. At the same time, the horizontal seal portion 100b is vertically cut by a cutter (not shown) attached to the horizontal heater blocks 5 and 6.

In the vertical bag making and filling machine of the above construction, the pair of horizontal heater blocks 5 and 6 for performing the horizontal sealing of the packaging film 100 are formed by the cylindrical packaging film 1.
Heat sealing (horizontal sealing) is carried out by sandwiching 00. At this time, if the pressing force (film sealing pressure) on the packaging film 100 is too large, the packaging film 100 is excessively crushed and coated on the inner surface of the packaging film. The existing heat-fusible resin is pushed out from the polymerization side end 100a and adheres to the heater surface 6a of the horizontal heater block 6 to prevent the bag from falling. In addition, the heat shrinkage and deformation of the packaging film 100 may be large and impair the aesthetic appearance. Furthermore, there is a possibility that the packaging film is broken by the network-like irregularities (knurls) provided on the heater surfaces 5a and 6a, thereby impairing the sealing property and causing poor sealing. On the other hand, if the film sealing pressure is too small, it takes a long time to perform the heat sealing (lateral sealing), and thus the horizontal sealing is not completely performed within the set time.
There was a possibility that defective sealing might occur partially.

[0007] As described above, due to poor adjustment of the film seal pressure by the horizontal heater blocks 5 and 6, an appropriate horizontal seal may not be realized. Therefore, conventionally, in order to apply an appropriate film sealing pressure to the horizontal heater blocks 5 and 6, a configuration in which the horizontal heater blocks 5 and 6 are opened and closed by using a pneumatic actuator such as an air cylinder having a cushioning property as a driving source. It was generally put to practical use.

[0008]

The opening and closing mechanism of the horizontal heater blocks 5, 6 driven by a pneumatic actuator has a merit that the structure is relatively simple and the manufacturing cost can be reduced. . However, since the supply pressure and flow rate of the compressed air for driving the actuator generally fluctuate easily, if the driving time is prolonged, the film seal pressure fluctuates, which may cause a drop failure or a seal failure. Had problems with stability. In addition, there has been an increasing demand for high-speed operation in recent vertical bag making and filling machines, and it has been pointed out that pneumatic actuators cannot cope with this high-speed operation.

In order to cope with such circumstances, Japanese Patent Publication No.
Japanese Patent No. 25542 discloses that a servo motor is used as a drive source of a horizontal sealer (horizontal heater block) and the servo motor is controlled to a constant rotation torque value so that the film seal pressure by the horizontal sealer is maintained at an appropriate pressure. A horizontal seal control method is disclosed. According to the prior art disclosed in the publication, the use of a servomotor as a drive source of the horizontal sealer makes it possible to cope with a high-speed operation of the vertical bag making and filling machine. However, in order to maintain the film seal pressure properly and to keep the rotation torque value of the servomotor constant, a complicated control system is required as described in the publication.

When the control system is installed in a vertical bag making and filling machine, not only does the product cost increase, but also the maintenance management requires specialized knowledge of the system, and the maintenance management is also performed by the manufacturer. Will depend on you. Therefore, there is a problem that not only must the user bear the cost required for the maintenance management, but also it is not possible to quickly adjust and repair malfunctions and failures. The present invention has been made in view of such problems of the related art, and has as its object to realize an appropriate horizontal seal extremely easily.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is to wrap a band-shaped wrapping film around the outer peripheral surface of a cylindrical forming tube, and vertically seal the overlapping side end of the wrapping film. While forming into a cylindrical shape,
A predetermined position of the packaging film is sandwiched between a pair of horizontal heater blocks that are opened and closed by using a servo motor as a drive source, and the packaging film is horizontally sealed to form a bag-like package, and the packaged object is passed through a forming tube inside the package. The vertical bag making and filling machine for filling is characterized in that a pair of horizontal heater blocks are adjusted so as to maintain a predetermined interval at the time of horizontal sealing, and the packaging film is sandwiched at the interval to perform horizontal sealing.

Since the horizontal heater block opens and closes using the servo motor as a drive source, it can cope with high-speed operation without any trouble. And this invention is a simple method of adjusting the interval at the time of the horizontal sealing of the horizontal heater block,
The proper horizontal seal is realized.

That is, by keeping the interval between the horizontal heater blocks at the time of the horizontal sealing constant, the packaging film sandwiched between the horizontal heater blocks has a constant thickness.
In the prior art described above, the horizontal seal was optimized by paying attention to the film sealing pressure on the packaging film.However, if a certain gap is maintained between the horizontal heater blocks during the horizontal sealing of the packaging film, Regardless of the film sealing pressure at that time, the packaging film will not be crushed beyond a certain thickness. Further, by crushing the packaging film to a certain thickness at the time of the horizontal sealing, the horizontal sealing portion is reliably heat-sealed by the horizontal heater block, so that a horizontal sealing without sealing failure can be realized. This has been confirmed by experiments by the present inventors.

The distance between the horizontal heater blocks at the time of the horizontal sealing can be set, for example, with the position where a pair of horizontal heater blocks are brought into contact with each other as the origin.
Further, for example, an interval at the time of the horizontal sealing of the horizontal heater blocks may be set based on a stroke from a position where the pair of horizontal heater blocks are in contact with each other to a fully opened position.

Next, the packaging film sealing device of the present invention comprises a servomotor as an open / close drive source for a pair of horizontal heater blocks, and a driving force of the servomotor to rotate or reciprocate around a spindle. And a driven link member that opens and closes each horizontal heater block in conjunction with the driven link member, and an interval adjusting unit that adjusts an interval at the time of horizontal sealing of each horizontal heater block. This seal device can realize an appropriate horizontal seal without requiring a complicated control system only by adjusting the horizontal seal interval by the interval adjusting means.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention applied to a vertical bag making and filling machine will be described in detail with reference to the drawings. FIG. 1 is a front view showing a packaging film sealing device according to an embodiment of the present invention. The packaging film sealing device includes a cylindrical packaging film 100 sent out of the forming tube 2 along the transport path.
(See FIG. 8) by horizontally opening and closing the pair of horizontal heater blocks 5 and 6.

That is, a pair of horizontal heater blocks 5, 6
Are slidably mounted on sliders 10 and 11, respectively. The pair of horizontal heater blocks 5 and 6 have heater surfaces 5 a and 6 a with the transport path of the packaging film 100 interposed therebetween.
Are facing each other, and the cylindrical packaging film 100 sent out from the forming tube 2 is
Heat sealing (horizontal sealing) is carried out by the closing operation along 0 and 11.

The heater surface 5 of each of the horizontal heater blocks 5 and 6
a and 6a are heated to a predetermined temperature by an electric heater (not shown). Note that one of the horizontal heater blocks 5 or 6
Has a built-in cutter (not shown) that can come and go from the heater surface 5a or 6a, and has a configuration in which the horizontal seal portion is vertically cut by the cutter. Further, the seal device is provided with a servomotor 12 as a drive source for opening and closing the horizontal heater blocks 5 and 6, and the driving force of the servomotor 12 is transmitted via a winding power transmission mechanism 13 and a link mechanism 14. The information is transmitted to the horizontal heater blocks 5 and 6.

The wrapping power transmission mechanism 13 includes the driving pulley 2
0, first and second intermediate pulleys 21 and 22, driven pulley 2
3 and first and second power transmission belts 24 and 25. The drive pulley 20 is fixed to the drive shaft 12a of the servomotor 12, and rotates (or reciprocates) integrally with the coaxial 12a. The first and second intermediate pulleys 21 and 22
Each is fixed to the support shaft 26, and both rotate integrally with the support shaft 26 (or reciprocate). In addition, the driven pulley 23
Is fixed to another support shaft 27. In addition, each support shaft 26,
Reference numeral 27 is rotatably supported by the body of the sealing device.

A first power transmission belt 24 is wound between the driving pulley 20 and the first intermediate pulley 21, and a second power transmission belt 25 is wound between the second intermediate pulley 22 and the driven pulley 23. It is hung. Thus, when the drive shaft 12a of the servo motor 12 rotates (or reciprocates), the drive pulley 20 rotates (or reciprocates) integrally with the drive shaft 12a, and the rotation (or reciprocates) is changed to the first position. The power is transmitted to the support shaft via the first power transmission belt 24, the first intermediate pulley 21, the second intermediate pulley 22, the second power transmission belt 25, and the driven pulley 23.

On the other hand, the link mechanism 14 comprises a driving link member 30, first and second intermediate link members 31 and 32, and first and second driven link members 33 and 34. The base end of the driving link member 30 is fixed to the support shaft 27 described above, and rotates (or reciprocates) integrally with the driven pulley 23. The first intermediate link member 31 is fixed to another support shaft 35. This support shaft 35 is also rotatably supported by the main body of the sealing device. First intermediate link member 31
Have link pieces 31a, 31b, 31c extending in three directions
One end of a second intermediate link member 32 is rotatably connected to one of the link pieces 31a. The other end of the second intermediate link member 32 is rotatably connected to the tip of the driving link member 30.

One end of each of the first and second driven link members 33 and 34 is rotatably connected to the remaining two link pieces 31b and 31c extending from the first intermediate link member 31, respectively. The other end of the first driven link member 33 is rotatably connected to one of the horizontal heater blocks 5, and the other end of the second driven link member 34 is rotatably connected to the other horizontal heater block 6. I have.

The link mechanism 14 includes a type in which the driving link member 30 rotates in one direction (hereinafter, referred to as a rotation type) and a type in which the link member 30 reciprocates (hereinafter, referred to as a reciprocating rotation type). ) Can be appropriately configured. FIG. 2 and FIG. 3 are schematic views showing the operation when the link mechanism 14 is configured as a rotary type.
FIGS. 4 and 5 are schematic views showing the operation when the link mechanism 14 is configured as a reciprocating rotation type. In these drawings, the servo motor 12 and the wrapping power transmission mechanism 1 are shown.
3 is omitted.

As shown in FIGS. 2 and 3, in the rotating type, two dead points exist during one rotation of the driving link member 30, and the first intermediate link member 31 is fixed at these dead points. It reciprocates in the angle range. Then, with the reciprocating rotation of the first intermediate link member 31, each of the horizontal heater blocks 5, 5 connected to the first and second driven link members 33, 34, respectively.
6 move close to each other (ie, open and close). Here, when the driving link member 30 is located at one dead center (the position in FIG. 3), the horizontal heater blocks 5 and 6 are in the most closed state, and when the horizontal heater blocks 5 and 6 are located at the other dead center (the position in FIG. 2). , The horizontal heater blocks 5 and 6 are in the most opened state.

On the other hand, as shown in FIGS. 4 and 5, in the reciprocating rotation type, the driving link member 30 reciprocates in a certain angle range. With the reciprocating rotation of the driving link member 30, the first intermediate link member 31 also reciprocates within a certain angle range. Then, with the reciprocating rotation of the first intermediate link member 31, the horizontal heater blocks 5, 6 connected to the first and second driven link members 33, 34 move closer to each other (ie, open and close).

As described above, the first intermediate link member 31
The operation of the horizontal heater blocks 5 and 6 does not change depending on the type. The structural difference between the rotary type and the reciprocating rotary type is that the driving link member 30
In the rotary type, the driving link member 30 is formed relatively short, while in the reciprocating rotation type, the driving link member 30 is formed relatively long.

Each of the horizontal heater blocks 5 and 6 is adjusted in advance so as to maintain a constant interval when in the closed position. Next, each horizontal heater block 5 in this closed position
The means for adjusting the interval between 6 will be described. As shown in FIG. 1, screw portions 33a, 33b, 34a, 34b are formed at both ends of the first and second driven link members 33, 34, and the screw portions 33a, 33b, 34a, 34b are respectively formed. When the nuts 36, 37, 38, and 39 are screwed together, the first and second driven link members 33 and 34 are connected to the first intermediate link member 31 and the horizontal heater via the nut members 36, 37, 38, and 39. It is connected to blocks 5 and 6. Then, by appropriately adjusting the screwing amounts of the screw portions 33a, 33b, 34a, 34b into the nut members 36, 37, 38, 39, the horizontal heater blocks 5,
The distance between the connection points between the first intermediate link member 6 and the first intermediate link member 31 can be adjusted.

In the case of the rotation type described above, the first and second
Screw portions 3 formed at both ends of driven link members 33 and 34
3a, 33b, 34a, 34b and nut members 36, 3
The mechanism for adjusting the distance between the connection points by 7, 38 and 39 constitutes an interval adjusting means between the horizontal heater blocks 5 and 6. That is, by changing the distance between the connection points between the horizontal heater blocks 5 and 6 and the first intermediate link member 31, the horizontal heater block in the case where the first intermediate link member 31 reciprocates in a predetermined angle range. The slide amount and slide position of 5, 6 change.

Therefore, in a state where the packaging film 100 is not interposed between the horizontal heater blocks 5 and 6, the horizontal heater blocks 5 and 6 are placed at the most closed positions, and the nut members 36, 37, 38 and 39 are placed. , The screw portions 33a, 33b, 34a, 3 of the first and second driven link members 33, 34
4b by adjusting the screwing amount of each horizontal heater block 5,
6 heater surfaces 5a and 6a are brought into contact. In this state, the first and second nut members 36, 37, 38, 39
Screw portions 33a, 33 of second driven link members 33, 34
By adjusting the screwing amounts of b, 34a and 34b, the space between the horizontal heater blocks 5 and 6 is expanded to set an appropriate interval.

On the other hand, in the case of the reciprocating rotation type, the interval between the horizontal heater blocks 5 and 6 can be adjusted by adjusting the angle range in which the servo motor 12 rotates. That is, the servo motor 12 is placed in a state where the packaging film 100 is not interposed between the horizontal heater blocks 5 and 6.
Is rotated in one direction to bring the heater surfaces 5a and 6a of the horizontal heater blocks 5 and 6 into contact with each other. Subsequently, the servo motor 12 is rotated in the reverse direction to move each of the horizontal heater blocks 5 and 6 to the fully open position. The fully open position is determined by the sliders 10, 11
May be arbitrarily set in advance in consideration of the total length of the image.

Thus, the horizontal heater blocks 5, 6
The stroke from the position where the heater surfaces 5a and 6a are in contact with each other to the fully open position is detected, and the angle range in which the servo motor 12 rotates is adjusted based on this stroke. For example, an encoder is attached to the servo motor 12 as a means for adjusting the interval between the horizontal heater blocks 5 and 6, and the encoder is provided between the position where the heater surfaces 5a and 6a of the horizontal heater blocks 5 and 6 are in contact and the fully open position. The number of pulses P output from is counted.

Further, the number Q of encoder output pulses corresponding to the interval to be maintained by each of the horizontal heater blocks 5 and 6 during the horizontal sealing is set. If the servo motor 12 is driven from the fully open position of the horizontal heater blocks 5 and 6 until the encoder counts the number of pulses of P-Q, the horizontal heater blocks 5 and 6 stop at the position where the set interval is maintained. Can be done.

Next, at the time of horizontal sealing, the horizontal heater blocks 5 and 5 are used.
Consider the proper spacing that 6 should hold. As shown in the plan view of FIG. 6, the tubular packaging film 100 is fed to an intermediate portion between the pair of horizontal heater blocks 5 and 6.
Subsequently, the tubular packaging film 100 is sandwiched between the horizontal heater blocks 5 and 6 as shown in the plan view of FIG. At this time, the cylindrical packaging film 100 is 2
The horizontal heater blocks 5 and 6 may hold an interval D (= 2d−α) narrowed by an arbitrary crush amount α from the thickness 2d of the sheet.

It is preferable that an appropriate value of the crushing amount d is determined in advance by an experiment in accordance with the material of the supplied packaging film 100 and the like. As described above, by adjusting the interval between the horizontal heater blocks 5 and 6 at the time of the horizontal sealing, there is no possibility that the packaging film 100 is crushed too much, and the horizontal sealing can be appropriately performed with an appropriate crush amount α.

The present invention is not limited to the above-described embodiment. For example, the method of sealing a packaging film of the present invention can be applied to a sealing device in various vertical bag making / filling / packaging machines other than the above embodiment. Can be applied.
Further, the packaging film sealing device of the present invention is not limited to the one having the mechanism as shown in FIG.

[0036]

As described above, according to the present invention,
By adjusting the interval between the horizontal heater blocks at the time of the horizontal sealing, an appropriate horizontal sealing can be easily realized.

[Brief description of the drawings]

FIG. 1 is a front view showing a packaging film sealing device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an operation when the packaging film sealing device shown in FIG. 1 is configured as a rotary type.

3 is a schematic diagram showing an operation when the packaging film sealing device shown in FIG. 1 is configured as a rotary type, similarly to FIG. 2;

FIG. 4 is a schematic diagram showing an operation when the packaging film sealing device shown in FIG. 1 is configured as a reciprocating rotation type.

FIG. 5 is a schematic diagram showing an operation when the packaging film sealing device shown in FIG. 1 is configured as a reciprocating rotation type, similarly to FIG. 4;

FIG. 6 is a plan view showing a state before a horizontal heater block and a packaging film are horizontally sealed.

FIG. 7 is a plan view showing a state when the horizontal heater block and the packaging film are horizontally sealed.

FIG. 8 is a perspective view showing the entire structure of the vertical bag making and filling machine.

[Explanation of symbols]

 1: winding drum 2: forming tube 3: feeding belt 4: heater for vertical sealing 5, 6: horizontal heater block 10, 11: slider 12: servo motor 13: winding power transmission mechanism 14: link mechanism 20: drive pulley 21: first intermediate pulley 22: second intermediate pulley 23: driven pulley 24: first power transmission belt 25: first power transmission belt 26, 27: support shaft 30: driving link member 31: first intermediate link member 32: Second intermediate link member 33: first driven link member 33a, 33b, 34a, 34b: screw portion 34: second driven link member 35: support shaft 36, 37, 38, 39: nut member

Claims (4)

[Claims] 1. A band-shaped wrapping film is wrapped around the outer peripheral surface of a cylindrical forming tube, and the overlapping side end of the wrapping film is vertically sealed to form a cylindrical shape.
A bag-shaped package is formed by sandwiching a predetermined position of the packaging film with a pair of horizontal heater blocks that are opened and closed using a servomotor as a drive source, and formed into a bag-like package, and the package is passed through the forming tube inside the package. In a vertical type bag making / filling / packing machine for filling an object, the pair of horizontal heater blocks are adjusted so as to maintain a predetermined interval at the time of horizontal sealing, and the packaging film is sandwiched at the interval to perform horizontal sealing. Packaging film sealing method. 2. The method for sealing a packaging film according to claim 1, wherein a position at which the pair of horizontal heater blocks are brought into contact with each other is set as an origin, and a horizontal sealing interval of the horizontal heater blocks is set. To seal the packaging film. 3. The packaging film sealing method according to claim 1, wherein a horizontal sealing interval of the horizontal heater block is set based on a stroke from a position where the pair of horizontal heater blocks are in contact with each other to a fully opened position. A method for sealing a packaging film. 4. A band-shaped wrapping film is wound around the outer peripheral surface of a cylindrical forming tube, and the overlapping side end of the wrapping film is vertically sealed to form a cylindrical shape.
A vertical type in which a bag-like package is formed by sandwiching a predetermined position of the packaging film between a pair of horizontal heater blocks that open and close to form a bag-like package, and the inside of the package is filled with the packaged object through the forming tube. In the bag making and filling machine, a servomotor as an opening / closing drive source of the pair of horizontal heater blocks, a driving link member that rotates or reciprocates around a spindle by obtaining a driving force of the servomotor, A sealing member for a packaging film, comprising: a driven link member that opens and closes each of the horizontal heater blocks in conjunction with a link member; and an interval adjusting unit that adjusts an interval of each of the horizontal heater blocks during horizontal sealing. apparatus.