JPH021656B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] This invention relates to a template used when bonding plastic sheets (including films) by high-frequency induction heating using a high-frequency welder or external heating using a heat sealing machine. More specifically, it relates to a template used when simultaneously gluing separate plastic sheets that have areas that require bonding and areas that do not require bonding.

[Conventional technology]

Conventionally, the electrode mold plate (electrode mold) used for high-frequency bonding of plastic sheets has been integrated with the base and the plate surface that contacts the plastic sheet of the base so that it has the same shape as the adhesive surface of the plastic sheet, or The base and the pressurizing part are made of a rigid metal such as brass, for example, and a bulging pressurizing part provided through fixing means such as brazing.

[Problem to be solved by the invention]

When applying a high-frequency voltage, when pressing a template against a plastic sheet, if the pressure applied by the pressure section is not uniform, uneven high-frequency adhesion will result. must be formed.

For this reason, it cannot be manufactured by an amateur and requires processing by a specialist, which poses a problem in terms of price.

Also, due to its rigidity, it is not possible to conform the template to the surface of the plastic sheet.

This has caused problems when high frequency bonding is applied to a large number of plastic sheets stacked at once.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a template for adhering plastic sheets, which allows a pressurizing piece to be brought into close contact with the surface of the plastic sheet and which is easy to manufacture.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a template used for bonding plastic sheets by high-frequency induction heating or external heating, in which a flexible thin pressure piece is attached to the contact surface of the plastic sheet of a flexible thin plate base. are fixed to each other so that the shape of the overlapping portion of the base and the pressure piece is made equal to the shape of the adhesive surface, and at least one of the base and the pressure piece is made to be a conductor.

[Effect]

When a template is pressed against a plastic sheet when applying a high-frequency voltage, even if the template is slightly deformed, it will be corrected by the pressure because it is flexible.
The entire surface of the pressure piece is uniformly brought into close contact with the plastic sheet surface.

〔Example〕

Figures 1 and 2 show templates used in the production of polymeric gusseted bags, called accordion bags.

This template 1 is composed of a base 2 and a pressure piece 3 provided on the plate surface of this base 2.

In the embodiment, the base 2 is made of a thin rectangular duralumin plate with a thickness of 0.5 mm, but it is made of an electric moving body, has a certain strength, and can be flattened when pressed on a surface plate. As long as it has sufficient flexibility, its material and thickness do not matter. but,
As will be described later, the thinner the material, the better the work efficiency.

The pressure piece 3 is formed by fixing a narrow band-shaped FRP piece (about 1 mm thick in the example) on the base 2 in a U-shape using a heat-resistant adhesive. This pressure piece 3 also has the flexibility to become flat when pressurized together with the base 2, and the thickness and material can be arbitrary as long as it is an electrical non-conductor. Good. The shape of the pressure piece 3 is the shape of the intended sheet adhesion surface.

Note that 4 is a connecting piece provided on the base 2, which is a thin metal band for connecting to the electrode of the high frequency welder.

Next, a method for manufacturing a polymer for a gusseted bag using the above-mentioned template 1 will be described.

First, unit 5 that constitutes the polymer of the gusseted bag
As shown in FIG. 3, the rectangular sheet has gusset forming pieces 6 bent inward on three sides.

The template 1 is inserted into this unit 5 between each gusset forming piece 6 and the unit body (FIG. 4). The unit 5 into which the template 1 has been inserted in this way is placed on the surface plate 7.
Further, the unit 5' without the template 1 inserted is placed on the unit 5, and the template 1 and the surface plate 7 are made of the same polarity, and the electrode mold 8, which is made of different polarities, is rolled down and a high frequency voltage is applied. If the pressure is applied (FIG. 5), even if the template 1 is slightly curved, it becomes flat, so that the gusset forming pieces 6 of the unit 5 are evenly bonded to the back surface of the unit 5'.

Next, insert the template 1 into the unit 5', place the unit 5'' without inserting the template 1 on top of the unit 5' (Fig. 6), and perform the gluing process described above to form the gusset of the unit 5'. Piece 6' is glued to the back side of unit 5''. If the operations are continued in the same manner, a gusseted bag polymer 9 is formed (FIG. 7).

Next, another embodiment of the template 1 will be described.

As shown in FIG. 8, a rectangular through-hole 2' is provided in the base 2, and the through-hole 2' is closed.
The pressure piece 3 is fixed onto the base so that the overlapping portion has the shape of the desired sheet adhesion surface.

Further, in the embodiment shown in FIG. 9, a U-shaped notch 2'' is provided in the base 2, and a pressure piece 3 is attached to the edge of this notch 2''.
Furthermore, the embodiments shown in FIGS. 10 and 11 are
Although the pressure piece 3 is made of a non-conductor, the base 2 is made of a conductor, and the lower plate 10 is made of a non-conductor, the lower plate 10 can also be made of a conductor.

Note that for adhesion by external heating such as heat sealing, a heat source such as a filament may be attached to the conductor portion of the template, and adhesion similar to the above-mentioned adhesion method using a high frequency welder is possible.

〔effect〕

As described above, the template for adhering plastic sheets according to the present invention is composed of a flexible thin plate-shaped base and a flexible thin pressure piece fixed to the plate surface of the base. Because of this, the pressure piece can be brought into close contact with the surface of the plastic sheet.

Therefore, uniform pressure is applied, and there is no unevenness in high-frequency bonding.

Further, since the fitting work required for rigid metal templates is not required, it can be easily manufactured even by an amateur, and the cost can be significantly reduced.

[Brief explanation of drawings]

The drawings show a template according to the present invention and an example of how the template is used. Figure 1 is a plan view of the template, Figure 2 is a sectional view taken along the line A-A in Figure 1, and Figure 3 is a cross-sectional view of the template. Fig. 4 is a plan view of the gusset forming assembly unit, Fig. 4 is a plan view with a template inserted into the same as above, Figs. FIG. 8, FIG. 9, and FIG. 10 are plan views of other sheets of the template, and FIG. 11 is a sectional view taken along the line B--B in FIG. 10. 1...template, 2...base, 3...pressure piece.

Claims (1)

[Claims] 1. In a template used for adhering plastic sheets by high-frequency induction heating or external heating, a flexible thin pressure piece is fixed to the contact surface of the plastic sheet of a flexible thin plate base, and the base and pressure are applied. A template for adhering plastic sheets, characterized in that the shape of the overlapping part with the piece is made equal to the shape of the adhesive surface, and at least one of the base and the pressure piece is made of a conductor.