JPS6288777A - Manufacture of cylindrical body - Google Patents

Abstract

PURPOSE:To remove bulges at both end edges generated on a belt-shaped body by forming a cylindrical body made of a plastic molding material by extrusion molding into the belt-shaped body with a folding roll and pressing both end edges of the belt-shaped body with a pressing roll. CONSTITUTION:A plastic material is injected through the hopper 11 of an extrusion molding machine 1 and extruded through a dice 12 as a cylindrical body 3. This cylindrical body 3 is folded by a folding roll to form a belt-shaped body 3A, and further bulges at both end edges of the belt-shaped body 3A are crushed by pressing both end edges with a pressing roll 10. At this time, the center section of the belt-shaped body 2A is somewhet separated. Then, predetermined positions are fused and sealed and cut to produce a plastic bag. Since this bag has no bulges at both end edges, no dislocation occurs even if many bags are stacked.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a plastic cylindrical body used for food packaging and the like.

[Conventional technology]

Conventional examples are shown in FIGS. 6 and 7. In the figure (1)
is an extrusion molding machine, and a plastic molding material (2) such as polyethylene or polypropylene is charged into the hopper aυ, heated by a heating mechanism installed inside the extrusion molding machine (1), and then extruded. It is extruded from the die as a cylindrical body (3) by a screw installed in the machine (1). Dice 02 is equipped with an air inlet,
By blowing air into the cylindrical body (3) from the air inlet as shown by the arrow in FIG. 6, the cylindrical body (3) is expanded and cooled. After that, the cylindrical body (8) is folded into a row/l/<
Guide conveyors (6), (6) suspended between 4), (4) and auxiliary rolls (5), (5)
) while being guided by folding holes (4) and (4) to form a strip (3)A, which is then melt-sealed at a predetermined location c3η and cut from the dotted line location as shown in Figure 7. It is said to be a bag (7).

[Mark while the invention is trying to solve]

In the above conventional method, the cylindrical body (3) is folded by folding rolls (4), as shown in FIG.
When this happens, bulges appear on both edges. Hence the bag (7)
Even when the bags (7) are stacked, one inch of the bulge remains, and as shown in Fig. 9, the bulges of the upper and lower bags (7) interfere with each other, causing the stacking positions to shift. Therefore, as shown in Fig. 10, when the stacked bags (7) are supported by the handles (8) and opened by the tea bag opening machines (9), (9), food etc. are filled into the bags (7). However, there was a problem in that the position at which the bag (7) is gripped by the handle (8) is shifted and the bag (7) comes off from the handle (8).

[Failure to solve the problem]

As a means to solve the above conventional problems, the present invention manufactures a cylindrical body (3) by extruding a plastic molding material (2) using an extrusion molding machine (1). is folded with a folding roll (4) to form a band-shaped body, and both ends of the band-shaped body (3) A are pressed with a pressing roller/L'OI.

[For production]

The effects of the present invention are as follows.

It is extruded into a plastic molding material using an extrusion molding machine to form a cylindrical body. The cylindrical body is folded by folding rollers to form a band-shaped body, with bulges at both ends.

Next, when both ends of the strip are pressed with pressure rolls, the bulge is crushed and the center of the strip is separated.

〔Effect of the invention〕

Therefore, in the present invention, even if the strips or bags made from the strips are stacked, the bulges will not interfere with each other and the positions of the strips or bags will not shift, so when filling the strips with food etc. Or the bag will never come off the handle.

〔Example〕

The present invention will be explained with reference to an embodiment shown in FIGS. 1 to 4. In the figure, (1) is an extrusion molding machine, in which polyethylene and polypropylene are processed from a hopper 〇υ.

Plastic materials (2) such as modified polyvinyl alcohol and polyamide are introduced into the extrusion F+llj type machine (1).
It is heated by a heating mechanism installed inside the extruder (1), and extruded from the die as a cylindrical body (3) by a screw installed inside the extrusion molding machine (1). As shown in Fig. 2, the die U is provided with a gap Q3A for extruding the cylindrical body (3) and an air blowing port (2B). (3) is expanded and cooled by blowing air into it from the air inlet 02B.Then, the cylindrical body (3) is folded into the folding row A/(4), (4) and the auxiliary row 5. ) and (5) are folded by the folding rolls (4) and (4) while being guided by the guide conveyors (6) and (6) suspended at 1' @ to form the band-shaped body (3) A. , by pressing both ends of the strip (3) A between the pressure rolls 110.01.
) Squeeze the bulges on both edges of A.

Then, as shown in FIG. 4, the center portion of the strip (3) A is slightly separated. Band-shaped body obtained in this way (3)
As shown in FIG. 7 of the conventional example, A is melt-sealed at a predetermined location C31) and cut from the dotted line location to form a bag <7). Even if a large number of mounts (7) are stacked, there is no bulge on both edges, so they can be stacked without shifting their positions, and as shown in Figure 1O, when filling food etc. There is a small amount (vacuum opening machine (9) because it is in the field),
(9) makes it easy to open, and JA (7) has a handle (8).
).

In addition to the above-described embodiments, for example, as shown in Figure ff15, the bulges at both ends of the strip +3)A may be crushed between the suppression roll 00A and the folding roll I-4).

[Brief explanation of drawings]

'$J Figures 1 to 4 show an embodiment of the present invention. Figure 1 is a process explanatory diagram, Figure 2 is a front view of the die, and Figure 3 is a die front view.
The figure is a perspective view of a folding roll part, FIG. 4 is a plan view of a strip, FIG. 5 is a schematic diagram of a folding roll part of another embodiment, and FIGS. 6 and 7 show a conventional example. Figure 6 is a process explanatory diagram,
FIG. 7 is a perspective view of the band in a melt-sealed state, FIG. 8 is a plan view of the band obtained in the conventional example, FIG. 9 is a view of the stacked bags, and FIG. In the figure, (1)... Extrusion molding machine, (2)... Plastic molding material, (3)... Cylindrical body, (3) A
... Band-shaped body, (4) ... Fold a-/L/, (I
I, QOA...Jp pressure o-tv patent applicant
Makoto Okumura; l-3 figure 4 figure 5 Roo 6 figure bu 8 figure ====:;

Claims (1)

[Claims] A cylindrical body is manufactured by extruding a plastic molding material using an extrusion molding machine, the cylindrical body is folded with a folding roll to form a band-shaped body, and both edges of the band-shaped body are pressed with a pressure roll. Characteristic manufacturing method of cylindrical body