JPH05131573A - Method for heat sealing opening port of cylindrical plastic film bag and apparatus for the same - Google Patents

Abstract

PURPOSE:To prevent the generation of pinholes, wrinkles, breaks, etc., at the time of fusion by fusing firmly a port attached to the opening of a cyrindrical plastic bag. CONSTITUTION:The opening 1a of a cylindrical plastic bag 1 is opened widely to insert a cylindrical port 2 into the opening 1a. The bag opening at the both sides of an inserted port position is heat sealed with heaters 36, 36' having a form evading the peripheral body part of the port 2, and then the bag opening is heat sealed to the peripheral body part of the port 2 with heaters 44, 44' having a form conforming to the peripheral body part of the port 2, so that the port 2 is fixed firmly to the bag opening 1a keeping airtightness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention seals an opening of a bag and welds the port by inserting a port of a mouth component into an opening of a bag made of a tubular plastic film such as an inflation tube. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a port heat sealing method and apparatus for a tubular plastic film bag.

[0002]

2. Description of the Related Art A plastic container for enclosing various liquid substances, for example, an infusion container, is conventionally manufactured by blow molding because it needs to be freely deformable. However, in blow molding, a mold is used. Since it is molded in units of one piece, it is expensive in terms of cost, and since it is formed in a bulged form, there is a problem that it becomes bulky during transportation of the empty container.

Therefore, recently, a method of forming a bag-shaped container from a tubular plastic film (inflation tube, hereinafter simply referred to as a tubular film) which is continuously formed into a tubular shape has been adopted. In order to manufacture a bag-shaped container from such a material, generally, a tubular film is heat-sealed in the width direction of the tubular film with a predetermined interval in the longitudinal direction, and this is cut and one end is opened. In the case of forming a bag made of a flat tubular film with sealed ends and enclosing a liquid substance for infusion, for example, as shown in FIG. 12, hard polyethylene or the like is provided on the opening 1a side of the bag 1. Insert the port 2 consisting of the plastic cylinder of the
It is welded to the opening 1a of the above and is formed so as to serve as a spout of the liquid material at the time of use.

The port 2 as described above is connected to the opening 1a of the bag 1.
When it is inserted into the inside of the bag 1 and welded to the opening 1a of the bag 1, conventionally, as shown in FIG.
The heating elements 5 and 5 having the flat portions 4 and 4 on both sides of the opening 1a of the bag 1 are the outer peripheral portions of the port 2 and the opening 1a of the bag 1.
And are heated and welded at the same time.

[0005]

However, according to the above-mentioned conventional welding means, since the heat capacities of the port 2 and the bag 1 are remarkably different from each other, a difference occurs in welding conditions between the port 2 and the opening 1a of the bag 1 to cause breakage. There is a problem in that the occurrence rate of defective products becomes high due to the occurrence of pinholes, pinholes, and wrinkles in the welded portion.

In view of the above, the present invention has an object to provide a method and apparatus for heat sealing a mouth portion of a tubular plastic film bag which can surely weld the port without generating pinholes or wrinkles. It was made as.

[0007]

SUMMARY OF THE INVENTION In order to solve the problems of the prior art described above, the present invention expands the opening of a tubular plastic film bag and inserts a tubular port into the opening. Then, the bag openings on both sides of the port insertion position are heat-sealed by using a heating body having a shape that avoids the peripheral body of the port, and then a heating body having a shape conforming to the shape of the peripheral body of the port is used to attach to the peripheral body of the port. A mouth opening port heat sealing method for a tubular plastic film bag, characterized in that the bag opening portion is heat-sealed and the port is airtightly fixed to the bag opening portion. An expansion device for expanding the portion, a port insertion device for inserting a cylindrical port into the opening expanded by the expansion device, and a port insertion device sandwiching the opening of the bag in which the port is inserted. Of the peripheral body of the port And a first seal portion having a pair of heating bodies each having a substantially U-shaped cross section with a recess into which the portion can be loosely fitted, and the first seal portion is provided on the downstream side of the first seal portion so as to sandwich the port insertion position. A second one having a pair of heating elements provided with a semicircular recess into which the half of the peripheral body of the port can be fitted as closely as possible.
And a driving means for moving at least one heating element of each of the sealing elements in a direction in which the heating element separates from or comes into contact with the other heating element, the mouth port heat of the tubular plastic film bag. The sealing device is defined as claim 2.

[0008]

The opening of the bag is opened and the port is inserted, both sides of the port insertion position are welded at the first seal portion, and then the peripheral surface position of the port is welded at the second seal portion.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings.

FIG. 1 shows an outline of the port heat sealing step according to the present invention. The bag feeding step (a) for receiving the bag 1 shown in FIG. 12 and the opening for expanding the opening 1a of the bag 1. Expansion step (b), port insertion step (c), side heat sealing step (first sealing section) (d) for heat sealing the openings 1a on both sides of the port 2, peripheral surface of the port 2 and opening Port heat sealing process for heat sealing with the portion 1a (second sealing portion)
(E), and a step (f) of taking out the completed bag.

A bag mounting table 6 of which one is shown in FIG. 2 so as to go through each of the above steps is moved at regular intervals by engaging rollers 7 and 7 at both longitudinal ends with rails 8 and 8. The toothed belts 9, 9 to which both ends of the bag placing table 6 are fixed are wound around toothed pulleys (not shown), and the pulleys are driven to rotate the bag placing tables 6 endlessly. It is moved and stopped at each of the process positions.

On the upper surface of the bag mounting table 6, one hole 10 is formed at the center of the bottom of the bag 1 and holes 11 and 11 are formed near both ends of the opening 1a. The pins 12, 13, 13 for determining the mounting position of the bag 1 are projected upward, and these pins are fitted in the holes 10, 11 of the bag 1 as shown in FIG.

The pin 12 for positioning the rear end of the bag 1 is fixedly mounted on the bag mounting table 6, and the pins 13, 13 for positioning the opening end of the bag 1 are provided on the lower surface side of the bag mounting table 6 with an arm 14 having an intermediate portion axially attached thereto. ，
14 is provided at the tip of the bag placing table 6 and is formed so as to extend in the width direction of the bag placing table 6.
A tension spring 16 is suspended between the rear ends of the arms 14 and 14 so that the pins 13 and 13 are biased outward, and at that time, the pins 13 and 13 are aligned with the holes 11 and 11 of the opening 1a of the bag 1. It is designed to fit in. Therefore, the opening 1a
The opening 1 of the bag 1 when the port 2 is inserted and welded to
When a is width-shifted, the pins 13 and 13 are elongated holes 15 and 15
Along with each other.

A window hole 17 is formed in the longitudinal center near the one end of the bag mounting table 6, and rods 19 and 19 of left and right air cylinders 18 and 18 supported on the lower surface of the bag mounting table 6 are formed.
The opening 1a of the bag 1 in which the pin-shaped port holder 22 for externally fitting and supporting the port 2 on the supporting portion 21 protruding from the window hole 17 of the movable frame 20 connected to the bag 1 is placed on the bag placing table 6. The rods 19 and 19 extend and retract so that the movable rod 20 can be moved between the port setting position and the port inserting position.

The expanding means used in the opening expanding step (b) for expanding the opening 1a of the bag 1 for inserting a port is performed when the bag material has a large wall thickness or a thin wall thickness. In order to ensure the opening even when the opening width is small, a spreading means for gripping and opening the film is used as shown in FIGS. 4 (A) and 4 (B). That is, the bifurcated claws 23A and 23B are provided so as to face each other above and below the position of the opening 1a of the bag 1 placed on the bag placing table 6 so as to be movable toward each other. Since the bifurcated claws 23A and 23B have the same structure, the upper side will be described. A pair of rods having claws 24A and 24A at the tips and an intermediate part pivotally supported by a support member 25A by a shaft 26A to be openable and closable. Member 27
A, 27A and rollers 28A, 28 at the rear ends of the rod members 27A, 27A for opening and closing the rod members 27A, 27A.
The rod member 27A, which is split between A, and the claw portion 24A of 27A,
It is composed of a wedge member 29A for opening and closing 24A and an air cylinder 30A as an example of a driving means for moving the wedge member 29A forward and backward.

As shown schematically in FIG. 5, the claw portions 24A and 24B of the forked claws 23A and 23B which are paired with each other are arranged so that the claw portions 24A, 24A and 24B and 24B are displaced from each other. Claw portion 2 of one forked nail 23A
4A and 24A are claw portions 24B and 24 of the other forked claw 23B.
It is designed to get in between B. The wedge members 29A and 29B are rollers 28A, 28A and 28B,
The claws 24A, 24A and 24B, 24B are closed when they are split between the 28B, so that the films forming the bag 1 are grasped by each other.

In the port inserting step (c), the port 2 is mechanically or artificially fitted to the port holder 22 in advance, and the opening 1a of the bag 1 is opened in the opening expanding step (b). When opened, the air cylinders 18, 18 of the bag mounting table 6 are shortened to draw the moving frame 20 and the port 2 is inserted into the opening 1a to a predetermined depth.

The sealing device used in the side heat sealing step (d) (first sealing section) and the port heat sealing step (e) (second sealing section) is shown in FIG.
FIG. 7B shows a structure in which a pair of upper and lower parts are taken out and shown in a side view in FIG. That is, the upper sealing device 3
1, a machine frame 34 is cantilevered so as to be vertically movable along a vertical guide rail 33 on a side surface of a frame 32 that is fixedly erected. A rod of the air cylinder 35 is connected, and a heating body 36 for heat sealing is provided in the lower part thereof. The heating body 36 is located at a position corresponding to the port insertion position of the bag 1 placed on the bag placing table 6. It is scented. Also this heating body 3
A port centering tool 39 is attached to a machine frame 38 which is provided on the corresponding front side of 6 and is vertically movable by an air cylinder 37 independently of the machine frame 34.

The port centering tool 39 has a V-shaped groove 40 into which the substantially half of the peripheral surface of the port 2 can be fitted into the opposing surfaces.
It has a pair of levers 41, 41 having 40, and these levers 41, 41 are designed to be opened and closed by a hand cylinder 42, and between the grooves 40, 40 of both levers 41, 41 near the outer end of the port 2. The port 2 is positioned at a predetermined position by sandwiching the under-neck portion thereof, and the port 2 is held stationary during heat sealing. The holding mechanism may have any other structure as long as it can center the port 2 and hold it at a predetermined position.

Since the lower sealing device 43 has the same structure as that of the heating element 36 of the upper sealing device 31, the reference numeral of the upper sealing device 31 is indicated by adding a dash, and the description thereof is omitted. To do.

As shown in FIG. 8, the heating element 36 of the sealing device 31, 34 in the side heat sealing step (d) has a U-shaped concave portion 36a into which the peripheral body portion of the port 2 can be loosely fitted, and both sides thereof. 9 is a heating portion 36b for heat-sealing the predetermined regions S ₁ and S ₁ on both sides of the port insertion position of the bag 1, as shown in FIG.
36b, so that heat is not applied to the peripheral body portion of the port 2.

As shown in FIG. 10, the heating element 44 used in the sealing device in the port heat sealing step (e) has a semicircular concave portion corresponding to the peripheral surface of the port 2 where the port 2 is inserted. The inner peripheral surface of this recess is a heating portion 44a for heat-sealing a predetermined area S ₂ corresponding to the peripheral surface of the port 2 inserted into the opening 1a of the bag 1 as shown in FIG.

In FIG. 6 (A), reference numeral 45 denotes a bag holder vertically provided on the machine frame 34 for supporting the heating body 36. When the machine frame 34 descends, it holds the essential parts of the bag 1 and when heat-sealing the bag. 1
This is for further preventing the slippage and for pressing the bag 1 so as not to come off from the pins 12 and 13 when the heating body is separated after sealing.

In the sealing devices 31 and 43, the object can be achieved by disposing at least one pair of the side heat seal heating body 36 and the port heat seal heating body 44. Along the moving trajectory of the above, 3 units were installed in series as the side heat sealing step (d) (first sealing section) and 3 groups as the port heat sealing step (e) (second sealing section), and 6 bags were installed. The number of installations is arbitrary, such as simultaneous sealing of each.

Next, the operation of the above embodiment will be described.

The bag 1 is supplied onto the bag placing table 6 and its pin 1
The holes 10, 11, 11 of the bag 1 are positioned and mounted so that the holes 2, 11, 11 fit into the bags 2, 13, 13 while the port 2 is fitted and supported by the port holder 22. Place this bag 1 and port 2
With respect to the support of, the automatic feeding and setting by hand or machine is possible.

When the bag placing table 6 on which the bag 1 is placed reaches the position of the opening expanding step (b) and stops, the supporting members 25A and 25B of the upper and lower bifurcated claws 23A and 23B drive the air cylinder or the like. By means of the means, the claw portions 24A, 24A of the bifurcated claws 23A, 23B are attached to the front and back surfaces of the opening 1a of the bag 1.
24B and 24B contact. Thereby, as shown in FIG. 5, the claw portions 24A, 24A and 24 of the bifurcated claws 23A and 23B are mutually connected.
Since B and 24B mesh with each other in an intersecting state, the film in that portion is in a wavy and folded state. After that, the air cylinders 30A, 30B are activated to operate the wedge members 29A,
29B enters between the rollers 28A, 28A, 28B, 28B, whereby the claw portions 24A, 24A and 24B,
Since 24B is closed, the front and back films that are folded in a corrugated shape are separated from each other by the claw portions 24A of the bifurcated claws 23A and 23B.
The openings 1a of the bag 1 are opened by moving the support members 25A and 25B in the separating direction after the gripping of 24A, 24B and 24B is completed and the gripping is completed.

After the opening 1a is widened in this way, the air cylinders 18, 18 of the bag placing table 6 are shortened and the moving frame 2 is moved.
0 is pulled toward the bag 1 side, and the port 2 fitted and supported by the port holder 22 is inserted into the opening 1a of the bag 1 together with the holder 22 to a predetermined depth, and then the hand cylinder 42 is extended. The centering tool 39 is lowered, the neck portion of the port 2 is positioned between the grooves 40, 40 of the levers 41, 41, and the levers 41, 41 are operated by the operation of the hand cylinder 42.
Is closed, the holder 2 is sandwiched between the grooves 40, 40, and the core is taken out and held.

After that, the air cylinders 35 and 35 'of the upper and lower sealing devices 31 and 43 are actuated to move the machine frames 34 and 34' closer to each other, and the heating elements 36 and 36 'are inserted into the opening 1a of the bag 1. The heating part 3 so that it straddles the port 2
6b and 36b are in contact with the upper and lower surfaces of the bag 1, and the predetermined regions S ₁ and S _{1 on} both sides of the port 2 are heat-sealed. At this time, the film in the opening 1a is pulled to the left and right, but since the portion in which the port 2 is inserted is not heat-sealed, it freely expands and contracts and does not cause pinholes or tears.

When the heat sealing of both sides of the port 2 is completed, the heating elements 36, 36 'are restored, the centering tool 39 releases the holding of the port 2, and the ascent is restored. Then, the bag mounting table 6 moves, and the process proceeds to the next port heat sealing step (e).

In this step, the sealing devices 31, 43 are
The heating device 44, 4 of FIG.
The predetermined area S ₂ corresponding to the peripheral surface of the port 2 is heat-sealed at 4 ′, whereby all heat-sealing of the opening 1 a is completed. After that or at a required time before that, the air cylinders 18, 18 of the bag placing table 6 are extended to retract the moving frame 20, the port holder 22 is pulled out from the port 2, and the bag placing table 6 is further advanced to complete the finished product. The bag is taken out. The empty bag mounting table 6 is circulated to the start side again by the endless rotation of the toothed belts 9 and is used for the above process.

[0032]

As described above, according to the present invention, both sides of the port inserted into the opening of the bag are heat-sealed, and then the peripheral surface of the port is heat-sealed. It is possible to enhance the safety of an infusion container without giving an excessive tensile force or local elongation, without causing pinholes, wrinkles, or breaking.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an outline of a process according to the present invention,

FIG. 2 is a perspective view showing one of the bag placing tables,

FIG. 3 is an explanatory view showing an engaged state of the bag and the bag placing table,

4 (A) and 4 (B) are front views showing an example of the opening expanding means of the bag,

5 is an explanatory view showing the operation of FIG. 4,

6A and 6B are perspective views showing an example of a sealing device,

FIG. 7 is a side view of the same,

FIG. 8 is an explanatory view showing the relationship between the heating element and the port used for the first sealing portion that seals the port side portion of the bag opening.

9 is an explanatory view showing a heat sealing area by the heating element of FIG. 8;

FIG. 10: Second seal for sealing the port peripheral surface of the bag opening
Explanatory diagram showing the relationship between the heating element and the port used in the seal portion of

FIG. 11 is an explanatory view showing a heat sealing area by the heating body of FIG.

FIG. 12 is a plan view showing an example of a tubular plastic bag obtained by the present invention,

FIG. 13 is an explanatory view of a conventional heat sealing device.

[Explanation of symbols]

 1 Bag 1a Open Port 2 Port 6 Bag Loading Table 9 Toothed Belt 12 Pin 13 Pin 20 Moving Frame 22 Port Holder 23A Bifurcated Claw 23B Bifurcated Claw 24A Claw 24B Claw 31 Upper Seal Device 36, 36 'First Seal Part heating unit 39 Port centering tool 43 Lower sealing device 44,44 'Second sealing unit heating unit

Claims (2)

[Claims] 1. A shape in which an opening portion of a tubular plastic film bag is expanded and a cylindrical port is inserted into the opening portion, and bag opening portions on both sides of the port insertion position avoid the peripheral body portion of the port. It is characterized in that it is heat-sealed using the heating body of No. 1, and then the bag opening is heat-sealed to the peripheral body of the port using a heating body having a shape conforming to the shape of the peripheral body of the port, and the port is airtightly fixed to the bag opening. A method for heat sealing the mouth port of a tubular plastic film bag. 2. An expansion device for expanding the opening of a tubular plastic film bag, a port insertion device for inserting a cylindrical port into the opening expanded by the expansion device, and this port A first seal portion having a pair of heating bodies having a substantially U-shaped cross section, the first seal portion being opposed to each other with the opening of the bag inserted, and having a recess into which a half portion of the peripheral body portion of the port can be loosely fitted; A second heating element having a pair of heating bodies provided on the downstream side of the seal portion, sandwiching the port insertion position, and provided with a semicircular recess into which a half portion of the peripheral body portion of the port can be fitted as closely as possible. A mouth port heat seal for a tubular plastic film bag, comprising: a seal part; and a drive means for moving at least one heating body of the respective sealing parts in a direction in which the heating body separates from and comes into contact with the other heating body. apparatus.