JPS6234612B2 - - Google Patents

Description

Detailed Description of the Invention A. Purpose of the Invention (Field of Industrial Application) This invention relates to a package made of a plastic cylindrical packaging film, in which the film is welded to the film in order to make it easier to tear the film and take out the contents. This invention can be used in a cut tape welding method and device.

(Prior Art) Packaging products in which food products such as ham, sausage, cheese, etc. are filled into a cylindrical plastic packaging film and both ends of the packaging film are ligated are widely used.
In such packages, the packaging film is torn to remove the contents, but since it is difficult to tear the film as it is, a cut tape is welded to the packaging film and the cut tape is moved away from the package, i.e. horizontally. The packaging film is torn and opened by pulling it.

FIG. 1 shows an example of such a plastic film package 14, in which a cylindrical packaging film 2 with cut tape 1 longitudinally welded to the side surface is filled with contents such as sausage, cheese, etc., and the open ends on both sides are The two ends are crimped and tightened with ligature fittings 3, 3. The cut tape 1 is a thin plastic film having a constant width of about 3 to 4 mm, and is welded to the packaging film 2, mostly strongly and partly weakly. The strength of the weld can be determined visually by the shade of the weld line, so it is possible to tear the packaging film and open it by pulling the weak part of the weld line sideways.

Conventionally, the cut tape 1 is welded to the packaging film 2 as shown in FIG. 2. Fig. 2 shows a film 2a unwound from a raw film 2b on which a long strip-shaped film 2a is wound, passed through guide rolls 4, 4 with a damper function, and a cut tape 1 is unwound from a raw film 1a on which a long cut tape is wound. Then, it is overlapped with the film 2a from the middle and sent to the forming plate 5 to form a cylindrical shape. A metal staff nozzle 6 for supplying the contents passes through the forming plate 5, and a positive electrode 7 for high-frequency electric welding, which uses this nozzle as a negative electrode, is stacked in a cylindrical shape on both sides of the strip film 2a. The edges are seam-welded in the longitudinal direction to form a cylindrical packaging film 2. A positive electrode 8 for high-frequency electric welding of the cut tape is placed next to the positive electrode 7, and the cut tape 1 is welded to the packaging film 2 using the staff nozzle 6 as a negative electrode. The contents sent by the pump 9 and flowing down the staff nozzle 6 are filled into the cylindrical packaging film 2, and after some of the contents have been pushed out by the squeezing roll 10, the packaging film is passed through the ligating machine. 11, the metal fittings 3 are tightly attached to each packaged product 14.

The applicant has developed and implemented a method of welding the cut tape 1 to the packaging film 2 as described above to facilitate the removal of contents.
No literature describing this technique is found.

(Problem to be Solved by the Invention) However, when the positive electrode 8 for cut tape welding is provided next to the positive electrode 7 for forming the packaging film, both electrodes 7 and 8 interfere with each other, resulting in poor welding. becomes unstable, and good welding cannot be performed. Moreover, this effect becomes particularly large when the contents are at a high temperature. Since the cut tape 1 intermittently varies the high-frequency electrical output to create a difference in welding strength to the packaging film 2, the above-mentioned interference makes it possible to adjust the seam welding of the packaging film and the welding strength of the cut tape, respectively. This is extremely inconvenient as it can no longer be done independently.

The present invention has been made in order to eliminate such inconveniences.

(Means for solving the problem) Conventionally, it was considered to use the staff nozzle 6 in common as the negative electrode for packaging film welding and the negative electrode for cut tape welding, so the positive electrodes 7 and 8 were close to each other. However, this invention breaks away from this concept of electrode configuration, and the welding of the cut tape 1 is performed at a position far away from the seam welding position of the packaging film to the extent that both electrodes do not interfere with each other. This eliminates the above inconvenience.

(Function) Since the positive electrode and negative electrode for cut tape welding are separated from the electrode for packaging film welding, the electrodes of both welding parts interfere with each other, making it possible to easily adjust the degree of welding at each electrode.

(Embodiment) FIG. 3 shows an embodiment of the present invention, and parts equivalent to those of the conventional example in FIG. 2 are given the same reference numerals and will be described below without explanation.

In this embodiment, a positive electrode 12 and a negative electrode 13 for welding the cut tape are provided in the middle of the belt-shaped film 2a, which becomes the cylindrical packaging film 2, and the cut tape 1, which are fed together by guide rolls 4, 4. The films 1 and 2a are seam welded intermittently with differences in strength.

Strip-shaped film 2a welded with cut tape 1
The forming plate 5 is formed into a cylindrical shape, and is seam-welded into the cylindrical shape by a positive electrode 7 with a staff nozzle 6 as a negative electrode, as in the conventional case.

In this way, the positive electrode 12 for cut tape welding,
Since the negative electrode 13 is separated from the packaging film welding electrode, there is no possibility that it will be difficult to adjust the degree of welding of both electrodes to each other or that welding defects will occur, and the cut tape can be welded well.

C. Effects of the invention (1) Since the packaging film welding electrode and the cut tape welding electrode are provided apart from each other to the extent that they do not interfere with each other, the welding degrees of packaging film welding and cut tape welding can be adjusted in conjunction with each other. There is no need for this adjustment, and this adjustment can be easily performed independently.

(2) Therefore, the packaging film can be reliably welded to prevent contents from leaking or spoiling due to defects.

(3) The cut tape can be easily welded to a state where it can be easily opened.

[Brief explanation of the drawing]

FIG. 1 is a perspective view illustrating a plastic film package, FIG. 2 is a schematic side view illustrating a conventional plastic film package manufacturing apparatus, and FIG. 3 is a schematic side view illustrating an embodiment of the same apparatus according to the present invention. It is a diagram. 1: Cut tape, 1a: Original fabric, 2: Packaging film, 2a: Strip film, 2b: Original fabric, 3: Ligation fitting, 4: Guide roll, 5: Forming plate, 6: Staff nozzle, 7, 8: Positive electrode, 9: Pump, 10: Straining roll, 11: Ligating machine, 12: Positive electrode, 13: Negative electrode, 14: Packaged product.

Claims (1)

[Scope of Claims] 1. A plastic film strip 2a pulled out from an original film 2b is sent to a forming plate 5 via a plurality of guide rolls 4, 4 having a damping effect, and is formed into a cylindrical shape surrounding a staff nozzle 6. When forming a cylindrical packaging film 2 by seam welding the overlapped side edges of the cylindrical film with a high-frequency electric welding positive electrode 7 with the stud fan nozzle 6 as a negative electrode, tape is applied in advance. A plastic cut tape 1 of a narrow constant width is pulled out from the original film 1a and overlapped on the strip film 2a, and is continuously cut at a position where it does not interfere with the packaging film welding electrode while passing through the guide roll 4 and reaching the forming plate 5. A cut tape welding method for a plastic film package, characterized in that continuous welding is carried out with a strip film 2a while the plastic film package is being moved, with a difference in welding strength in the longitudinal direction. 2. It has a plurality of guide rolls 4, 4 that apply a damping effect to the plastic film strip 2a that is pulled out from the original film strip 2b and sent to the forming plate 5.
In a plastic packaging machine equipped with a positive electrode 7 that seam-welds the overlapped side edges of a cylindrical film strip 2a with high-frequency electricity using a staff nozzle 6 as a negative electrode, the raw material of the plastic cut tape 1 is A cut tape 1 of a narrow constant width is pulled out from the film strip 1a, overlapped with the film strip 2a, and passed through the guide rolls 4, 4. During continuous movement, a high frequency wave is applied to the film strip 2a with alternating strengths and weaknesses in the length direction. Positive electrode 12 for electric welding
and a negative electrode 13 are provided at a position that does not interfere with the packaging film welding electrode between the guide roll 4 and the forming plate 5.