JPH0339822B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a cylindrical body for a folding box by gluing the ends of a folding box original sheet.

As shown in FIG. 8, a sheet of paper or plastic is punched into a predetermined shape, and a folding box original sheet 5 with folding lines 53 attached thereto is folded into a cylindrical shape and the ends are glued together to form a cylindrical body for a folding box. A so-called folding box is widely used, in which the cylindrical body is kept in a folded state and then unfolded when filling with contents and assembled as shown in FIG. 9. In recent years, there has been an increase in the production of the above-mentioned folding boxes especially from plastic sheets, but because plastic sheets are more easily scratched than paper and generate static electricity, conventional paper sheet manufacturing processes require long processes. Problems due to scratches and static electricity are likely to occur, and the solvent used for adhesion evaporates during the long process, so it is not possible to form a cylinder by gluing the ends of the original sheets together. The problem was that it was difficult.

The present invention aims to solve the above-mentioned problems and provide a method for highly efficient gluing the edges of plastic folding box base paper, and will be described in detail below with reference to the drawings.

FIG. 1 is a schematic plan view showing an example of an apparatus used for carrying out the method for bonding the edges of folded box original sheets of the present invention, and FIG.
The figure is a schematic front view, Figures 3 to 7 are enlarged cross-sectional views to - enlarged cross-sectional views of the original sheet placed in Figure 1, and Figure 8 shows an example of the original folding box sheet. The developed view shown in FIG. 9 is a perspective view showing a state in which the original sheet shown in FIG. 8 is assembled. In addition, in FIGS. 3 to 7, the thickness of the original sheet is exaggerated for easy understanding.

As shown in FIGS. 1 and 2, the present invention includes an adhesive applicator 2 that sequentially applies a solvent-based adhesive along the sides of a belt conveyor 1 in the direction of movement of the belt conveyor, This is carried out by a folding box original sheet edge bonding device which is equipped with a folding device 3 and a pair of adjoining endless belts 41 and 42 equipped with a heater 43 that pressurizes and heats the edges of the original sheet.

Belt conveyor 1 is driven by pulleys 11 and 12.

And on the top surface is a folding box original sheet 5 to be conveyed.
The guide 13 is placed in contact with the upper surface of the belt conveyor to prevent the original sheet from shifting left and right, and the presser belt 14 is placed in contact with the upper surface of the belt conveyor to prevent the original sheet from shifting vertically and horizontally between the adhesive applicator 2 and the endless belts 41 and 42. It is preferable to install it as follows.

On the side of the belt conveyor 1, an adhesive applicator 2, an adhesive folding device 3, and a pair of adjoining devices are installed so that the end portion of the raw sheet 5 to be conveyed that protrudes to the side of the belt conveyor passes in sequence. It is necessary to install the endless belts 41 and 42 one after another.

As shown in FIG. 4, the adhesive application device 2 can be one that applies the adhesive by rotating an application roller 21 attached to an adhesive container. Instead of the roller 21, a cotton-like material may be dipped in the adhesive and applied by sliding the adhesive (not shown).

The adhesive folding device 3 may be any device that gradually bends the adhesive strip 51 of the original sheet coated with adhesive, folds it in about 180 degrees, and folds it over the other end 52 of the original sheet. Figure 1, Figure 2, Figure 5
As shown in FIG. 6, a folding guide 31 supports the original sheet from below and determines the folding position.
A folding roller 32 pairs with this guide and rotates and presses the adhesive strip 51 from above to bend it approximately 90 degrees, and as shown in FIG. 6, it guides the adhesive strip 51 bent at 90 degrees. Folding guide 33 for folding deeper into approximately 180 degrees
can be used. Here, instead of the bending roller 32, a plate-like body (not shown) having an oblique end surface extending from above to below the glue strip 51 and capable of pressing the glue strip can be provided. good.

A pair of endless belts 41 and 42 are connected to a first
As shown in FIG.
The end of the original sheet 5 is squeezed between 2 and pressurized.
It presses the folded adhesive strip 51 and the other end 52, and is preferably disposed as close as possible immediately after the adhesive strip folding device 3 in order to quickly narrow the folded adhesive strip 51 and the other end 52. Then, it is necessary to provide a heater 43 in order to heat the end portions in this press-contact state to completely bond them. Specifically, as shown in FIG. 2, the endless belts 41 and 42 are made of metal bands such as steel belts, and heaters 43 are arranged on both sides of their contacting parts, so that the heat transmitted through the belts 41 and 42 is It is possible to use a device which can heat the end portion of the original sheet which is compressed by being pinched by the belt.

The belt conveyor 1, presser belt 14, and endless belts 41, 42 are connected to and driven by a power unit 6 via respective pulleys, as shown in FIG.

Next, a process of forming the original sheet 5 into a cylindrical body using the above-mentioned folding box original sheet edge bonding device will be described.

The folding box original sheet 5 as shown in FIG.
And as shown in FIG.
A folding ruled line 53 is formed so as to protrude outward from 2.
1, and place it on the upper surface of the belt conveyor 1 so that the glue allowance piece 51 is located above the other end 52. At this time, the position of the original sheet 5 on the belt conveyor 1 is regulated by the guide 13, and as the original sheet 5 is conveyed in the direction of the arrow 7, the adhesive strip 51 accurately passes through the adhesive applicator 2. Adjust accordingly. Subsequently, the original sheet 5 is held between the belt conveyor 1 and the belt conveyor 1 by the presser belt 14, and is fixed and conveyed so as not to shift.

When the raw sheet 5 being conveyed passes through the adhesive coating device 2, the lower surface of the adhesive strip 51 is brought into contact with the coating roller 21 as shown in FIG.
Move while rotating. At this time, roller 2
Since the lower part of the roller 21 is immersed in adhesive, the adhesive adhered to the roller 21 is accurately applied to the adhesive strip 51.

The adhesive used at this time is preferably a solvent for the plastic sheet constituting the raw sheet 5; for example, in the case of a polyvinyl chloride raw sheet, tetrahydrofuran can be used.

Next, as shown in FIG. 5, while the position of the folding ruled line 532 of the original sheet 5 is supported from below by the folding guide 31, the glue margin piece 51 is gradually pressed from above by the rotation of the folding roller 32, so that the original sheet 5 is bent by about 90 degrees. Fold it up to a certain degree. Furthermore, as shown in FIGS. 1 and 6, the adhesive strip 51 is pushed in from the outside by the contact surface 34 of the folding guide 33 that bites diagonally inward below the original sheet 5, and folded deeper into the lower surface of the other end 52. .

Next, as shown in FIGS. 1 and 7, due to the elasticity of the plastic, the deeply folded adhesive strip 51 is quickly narrowed from above and below by a pair of opposing endless belts 41 and 42 before it can be folded back. Find it and apply pressure to press the other end 52 of the glue margin piece 51. Furthermore, in this pressed state, the glue margin piece 51 and the other end 52 are heated by the heater 43 to completely adhere them, thereby completing a cylindrical body for a folding box.

Here, a raw sheet made of transparent hard polyvinyl chloride with a thickness of 0.2 mm was used, tetrahydrofuran was used as an adhesive, the conveyance speed was set to 6 m/min, and endless belts 41 and 42 made of steel with a thickness of 0.15 mm were used. When gluing the heater 43 with a length of 10 cm, the heater temperature was set to approximately 80°C.
A cylindrical body for a folding box with good transparency at the adhesive part and sufficient strength for practical use was obtained. FIG. 9 shows a state in which this is unfolded and assembled by folding from each ruled line 53.

As described in detail above, according to the folding box original sheet edge adhesion method of the present invention, the folding box original sheet 5 is folded in half with the glue margin piece 51 protruding and conveyed. Since the solvent-based adhesive is applied, the glue strips are folded, and the glue strips are heat-pressed in sequence, the solvent evaporates by quickly folding only the glue strips coated with the solvent-based adhesive. There is no fear. Also, since only the narrow adhesive strip is bent, the solvent will not scatter and adhere to other parts.

Further, since the original sheet portion other than the adhesive sheet is conveyed without being subjected to any processing while being placed on the belt conveyor, static electricity and scratches do not occur even if the sheet is made of plastic. Since the series of steps is applied only to the adhesive strip of the original sheet, the device is small and inexpensive, and can perform bonding at high speed, which is preferable.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing an example of an apparatus used for carrying out the method for bonding the edges of folded box original sheets of the present invention, and FIG.
The figure is a schematic front view, and Figs. 3 to 7 show the state in which the original sheet is placed in Fig. 1.
8 is a developed view showing an example of the original sheet for folding boxes, and FIG. 9 is an enlarged view of each cross section.
FIG. 3 is a perspective view showing the assembled state of the original sheet shown in the figure. 1... Belt conveyor, 2... Adhesive applicator, 3
...Glue allowance folding device, 41, 42...Endless belt, 4
3...Heater, 5...Folding box original sheet, 51...Glue allowance piece, 52...Other end of folding box original sheet.

Claims (1)

[Claims] 1. The folded box original sheet 5 folded so that the glue margin piece 51 protrudes outward from the other end 52 is placed and conveyed so that the glue margin piece and the other end protrude to the side of the belt conveyor 1. The adhesive coating device 2 installed on the side of the belt conveyor 1 coats the adhesive strip 5.
1 is coated with a solvent-based adhesive, and then only the adhesive piece 51 is bent by the adhesive piece bending device 3 installed on the side of the belt conveyor 1 and overlapped with the other end 52, and then A pair of adjoining endless belts 4 equipped with heaters 43 installed in
1. A method for adhering an edge of a folding box original sheet, characterized in that the glue margin piece and the other end are welded together under heat and pressure.