JPH0694175B2 - Synthetic resin container manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a synthetic resin container used for storing or transporting a liquid or the like.

[Conventional technology]

Generally, various shapes have been proposed and implemented as containers used for storage and transportation of liquids, and one of them is a container manufactured by blow molding. As an example, as shown in FIG. 7, a molten synthetic resin is discharged from a nozzle 1 connected to a molding machine into a cylindrical parison 2 (FIG. 7 (a)), and the lower part of the parison 2 is discharged. Is sealed by the sealing device 3. Next, the seal part of the parison 2 is sandwiched in the mold 5 and air is injected from the hole 4 of the nozzle 1 to expand it to obtain a container material a ′ (intermediate body of container) having a predetermined container shape. (Fig. 7 (b)).

Then, the part of the parison 2 above the container material a ′ held in the mold 5 is cut by the heat cutter 6 (FIG. 7C).

After that, the mold 5 is closed, high-pressure air is supplied from the air supply pipe 8 to form the container material a ′, and the mold 5
Is cooled with water (Fig. 7 (d)).

After that, as shown in FIGS. 7 (e) and 7 (f), the mold 5 is opened to take out the container material a ', and the burr 10 formed around the container material a'is cut to obtain the structure shown in FIG. 7 (g). The container a is formed as shown.

[Problems to be Solved by the Invention]

By the way, when a container is manufactured by blow molding as described above, a container material having an approximate shape of the container is formed by expanding in a mold from a cylindrical parison, and at the same time, a nozzle is integrally formed from the container material. Due to this, many burrs are generated around the container. Since this burr is a useless material, not only the yield of raw materials is poor, but also the thickness of the container is thick and the accuracy is poor because of unevenness.

In addition, this blow molding includes a parison discharge step, a blow molding step, a nozzle section molding step, and a deburring step.
It is difficult to perform continuous molding in a short time because it involves a plurality of different processes, and it is particularly unsuitable for mass production because it is necessary to handle each container in the subsequent process. .

[Means for Solving the Problems]

The present invention is made in order to solve the conventional problems as described above, and a flat tube by double-folding a tube made of a synthetic resin sheet in the diameter direction,
In the widthwise central portion of the flat tube, the nozzle holes are opened by penetrating the tube at a predetermined interval in the longitudinal direction, and the nozzles are respectively positioned in the upper and lower nozzle holes opened in the two sheets, Each nozzle is welded to a tube, the flat portion of the flat tube is pulled, and the flat tube is flattened so that the flat tube is double-folded by changing the bending direction by 90 °. And a middle portion of each nozzle in the longitudinal direction is welded, and the welded portion of the tube is cut to produce a synthetic resin container.

[Action]

Make a hole for the nozzle in the tube made of flattened synthetic resin sheet, attach the nozzle to this hole respectively, change the flattening direction so that this nozzle is located at the edge of the tube, and change the center part of this tube Since the bottom is sealed, it is possible to efficiently manufacture a large amount of synthetic resin containers.

〔Example〕

An embodiment of the method for manufacturing a synthetic resin container according to the present invention will be described below with reference to FIGS. 1 to 6.

First, in FIG. 1, 11 is a flatly folded tube made of a synthetic resin sheet having a container thickness,
The width W of this tube 11 is selected to be at least twice the depth D (the length between the shoulder and the bottom) of the container 12 described below. A nozzle hole 13 is provided at the center of the flat tube 11 in the width direction, and a predetermined space L is provided in the longitudinal direction of the tube 11, that is, the width is the same as the width 1 of the container 12 shown in FIG. The nozzle holes 13 are opened at intervals L. Needless to say, this hole 13 is opened through the two sheets.

Between the nozzle holes 13 and the width l of the container 12
A plurality of feed holes 14 are formed at more deviated positions by a punching device (not shown) (first step).

A nozzle 15 having a sealable surface provided with a bendable flange is attached to each nozzle hole 13 penetrating the flat tube 11 by welding or the like.

Specifically, as shown in FIG. 2, the nozzle 15a is set in the nozzle hole 13a below the tube 11, and as shown in FIG. 3, it has a pedestal 16 and a heater 17 which are vertically movable. Further, the flange of the nozzle 15a is welded to the periphery of the nozzle hole 13a by a heat seal device including a heater table 18 that can move up and down.

Then, after that, the nozzle 15b having the same structure as that described above is set in the nozzle hole 13b located on the upper surface of the flat tube 11, and as shown in FIG. And the heater table 21 that can be moved up and down causes the nozzle 15b
The flange is welded around the nozzle hole 13b (second step).

Nozzles 15a and 15b are attached to the nozzle holes 13a and 13b formed through the flatly folded tube 11 in this way along the same axis, and then the tube 11 is moved to the left in FIG. To be done.

On the other hand, the nozzle 15a along the transfer line of this tube 11,
Guide rails 22 and 23 are provided in the moving direction of 15b, and the guide rails 22 and 23 hold the necks of the nozzles 15a and 15b attached to the front and back surfaces of the tube 11, respectively. The guide rails 22 and 23 are arranged so that the distance gradually increases from the entrance to the exit. So this tube
When the tube 11 advances, the central portions of both sides of the tube 11 are pulled to form a double fold with the 90 ° bending position changed. In this state, the nozzle is placed in the opposite direction of both edges of the flat tube 11.
15a and 15b are installed.

Next, as shown in FIG. 5, the central portion 24 in the width direction of the tube 11 whose bending direction is changed and the nozzles 15a, 15 in the longitudinal direction are formed.
The central portion 25 of b is fixed by means such as welding (third step).

The central portion 24 will form the bottom of the container 12 and the central portion 25 will form both sides of the container 12.

Then, by cutting the welded central portion 24 and central portion 25, the synthetic resin container 12 is manufactured as shown in FIG.

Although the process of attaching the nozzle to the tube and welding as means for adhering the positions corresponding to the bottom and side of the container have been described as welding, this adhering method includes heating and melting, ultrasonic wave, high frequency wave, hot It is also possible to adopt a method of using a melt material, or a method of using an adhesive capable of adhering in a short time in some cases.

A sheet-like flange is formed on the nozzle attachment part, but this flange needs to be flexible enough to be folded in two. Since it is fixed on the front and back surfaces, the processing method is simple. Further, since two containers whose bottoms are combined are manufactured at the same time, the containers can be manufactured extremely efficiently.

〔The invention's effect〕

As is clear from the above description, according to the method for manufacturing a synthetic resin container of the present invention, a tube made of a synthetic resin sheet is double-folded to form a nozzle hole, and the nozzle is attached to the hole portion and then folded. A synthetic resin container can be manufactured by changing the direction by 90 ° to form a double-folded flat tube, and welding and cutting the positions corresponding to the bottom and side of the container 12.

Therefore, a plurality of synthetic resin containers can be simultaneously manufactured by this extremely simple means, and since many burrs are not generated unlike in blow molding, the yield of raw materials is good and the quality is improved. be able to. Since a container can be manufactured from a continuous tube, it is suitable for continuous molding, and is particularly suitable for mass production of containers.

[Brief description of drawings]

1 to 6 illustrate an embodiment of a method for manufacturing a synthetic resin container according to the present invention. FIG. 1 is a perspective view of a tube having holes such as nozzle holes, and FIG. It is explanatory drawing of the state which changes a nozzle attachment and the position of the edge part of the double fold of a tube. 3 and 4 are side views of main parts of the nozzle welding device, FIG. 5 is an explanatory view of welding at a predetermined place, and FIG. 6 is a side view of a container. Further, FIGS. 7A to 7G are explanatory views of an example of a conventional method for manufacturing a synthetic resin container. DESCRIPTION OF SYMBOLS 1 ... Nozzle, 2 ... Hollow cylindrical parison 3 ... Sealing device, 4 ... Hole 5 ... Mold, 6 ... Heat cutter 8 ... Inlet part, 9 ... Container nozzle 10 ... Burr, 11 ... Tube 12 ... Container, 13 ... Nozzle Holes 14… Feed holes, 15… Nozzles 16, 19… Receiving stand, 17,20… Heater 18,21… Heater stand, 22,23… Guide rails 24… Center part, 25… Central part.

Claims (1)

[Claims] 1. A flat tube made by double-folding a tube made of a synthetic resin sheet in a diameter direction, and a nozzle hole penetrating the flat tube at a predetermined interval in the longitudinal direction at a central portion in the width direction of the flat tube. , And position the nozzles in the upper and lower nozzle holes opened in the two sheets, weld each nozzle to the tube, pull the flat portion of the flat tube, flatten the bent portion, and The flat tube is made into a double fold with the bending direction changed by 90 °, and the tube is welded to the middle part in the width direction and the middle part of each nozzle in the longitudinal direction, and the synthetic resin obtained by cutting the welding part of the tube Manufacturing method of container.