JP2520912Y2 - Multi-bag container mold structure - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-bag container molding die structure, and more particularly to a novel improvement for sealing a connecting portion between bags in the same step during hollow molding.

[0002]

2. Description of the Related Art Conventionally, in the case of hollow molding of a multi-bag container of this type which has been conventionally used, a pair of mold parts 1 shown in FIG. 5 is generally used and extruded by an extruder (not shown). The formed parison (not shown) is hollow-molded by the cavity 2 for the first bag, the connection cavity 3 and the cavity 4 for the second bag of this mold portion, and the molded hollow molded product (not shown) is molded into the mold. The multi-bag container was manufactured by taking out from the part 1 and sealing the connecting part of each bag of the hollow molded product using a sealing machine.

[0003]

Since the conventional multi-bag container molding die structure is constructed as described above, the following problems exist. That is, in the case where the parison is put in the mold part and hollow-molded, the air supplied into the parison is supplied from the cavity for the first bag to the second cavity via the connecting cavity.
Since it is guided into the bag cavity, the ventilation hole is also formed in the connection part of the hollow molded product corresponding to the connection cavity after molding, and the connection part of the hollow molded product taken out from the mold part is sealed. Since it has to be sealed by a machine and the number of steps is increased, it is impossible to avoid the production efficiency and cost increase. In addition, since the resin still swells from the sealed state in the sealed portion, the vicinity of the boundary between the sealed portions is extremely thin, and the reliability of the product remains a problem.

The present invention has been made in order to solve the above problems, and in particular, a multi-bag container molding die structure capable of sealing a connecting portion between bags in the same process during hollow molding. The purpose is to provide.

[0005]

A multi-bag container molding die structure according to the present invention is a multi-bag container molding die structure in which a parison is hollow-molded into a required shape using a pair of openable and closable mold parts. In at least a first bag cavity and a second bag cavity formed in the mold part, a connecting cavity for connecting the cavities, and a piston provided in the mold part and configured to be retractable. And a cylinder that has a structure in which the piston seals the connecting portion of the hollow molded product in the connecting cavity.

[0006]

In the multi-bag container molding die structure according to the present invention, since the cylinder having the piston that can freely move in and out is provided in the mold part, the parison extruded from the extruder is sandwiched between the mold parts, When air is supplied into the parison for hollow molding, a plurality of bags are formed along the inner wall of each bag cavity and a connecting portion is formed between the bags. By pressing with, the connecting portion is sealed, and the bags do not communicate with each other. Therefore,
In the molding process of the same process, molding of each bag and sealing of the connecting portion are simultaneously performed. That is, since the hollow molded product is sealed before being cooled and solidified in a swelled state, the change in wall thickness is reduced, the occurrence of pinholes is suppressed, and a high-quality multi-bag container can be obtained.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a multi-bag container molding die structure according to the present invention will be described in detail below with reference to the drawings. Note that the same or equivalent parts as those in the conventional example will be described using the same reference numerals. 1 to 4 show a multi-bag container molding die structure according to the present invention, FIG. 1 is a plan view showing one mold portion, FIG. 2 is a side view of FIG. 1, and FIG. FIG. 4 is a sectional view showing the cylinder of FIG. 4, and FIG. 4 is a side view showing the hollow molded product after the hollow molding.

In FIG. 1, reference numeral 1 designates a pair of second mold parts 10 and a first mold openable and closable.
A mold part, and a mold 11 composed of these mold parts 1 and 10.
The extruder 1 for extruding the parison 12 is located above
3 are provided.

Each of the mold parts 1 and 10 has a first bag cavity 2, a connecting cavity 3 and a second bag cavity 4.
A cylinder 15 having a piston 14 is formed in the first mold part 1 corresponding to the connection cavity 3.
Is provided with a seal portion 16.

The seal portion 16 is constructed as shown in FIG. 3, and the cylinder 15 is formed with a first hole 18 and a second hole 17 for supplying air or oil. The seal portion 16 is not limited to the pneumatic or hydraulic cylinder type, but may be an electromagnetic cylinder type.

The tip 14a of the piston 14 is constructed so as to project into the connecting cavity 3, and the piston 14 can be moved in and out through the holes 17 and 18 of the cylinder 15 by, for example, supplying air pressure. And the piston 14 has a stroke L shown in FIG.

Next, in the above-described structure, first, the seal portion 16 is operated to retract the piston 14 by the stroke L, and the die portions 1 and 10 are opened. The parison 12 is hung from the mold, and when the parison 12 is positioned in the mold 11, the mold parts 1, 1
When the mold 0 is closed, the parison 12 becomes
Located within 3,4.

In this state, when air is supplied into the parison 12 through a supply unit (not shown), the parison 1
2 is hollow-molded along the inner walls of the cavities 2, 3 and 4, and in the mold 11, a shape of a multi-bag container having a pair of bags 20 and 21, a connecting portion 22 and inlet portions 23 and 24 is formed. The hollow molded product 30 is molded as shown in FIG.

In this case, at the same time as this molding, before the hollow molded article 30 is cooled and solidified, air pressure is sent to the seal portion 16, the piston 14 moves forward, and the tip 14a of the piston 14 moves to the connecting portion 22 (this The state before sealing has a thickness shown by the dotted line in FIG. 4), so that the piston 14
As a result, the connecting portion 22 is thinned from a dotted line to a solid line, and at the same time, a communication hole (not shown) formed inside is crushed to seal between the bags 20 and 21.

Therefore, by performing the above-mentioned hollow molding and sealing operation at the same time, as shown in FIG. 4, a hollow molded article 30 having a pair of bags 20 and 21 and having completed sealing,
Obtained by one and the same step.

In the above embodiment, the pair of bags 20,
Although the case of the mold 11 having the pair of bag cavities 2 and 4 for molding 21 has been described, it is also possible to form, for example, one or more bags.

[0017]

Since the multi-bag container molding die structure according to the present invention is constructed as described above, the following effects can be obtained. That is, since a piston that can freely move in and out of the mold is provided, it is possible to simultaneously seal the connecting portion during hollow molding in the same process, eliminating the sealing process that was a separate process in the past, and eliminating the manufacturing process. The efficiency can be greatly improved. In addition, since the hollow molded product is sealed before being cooled and solidified in a swelled state, the change in wall thickness after sealing is reduced, and a high quality hollow molded product without problems such as pinholes can be obtained.

[Brief description of drawings]

FIG. 1 is a plan view showing one mold part of a multi-bag container molding mold structure according to the present invention.

FIG. 2 is a side view of FIG.

3 is a cross-sectional view showing the cylinder of FIG.

FIG. 4 is a side view showing a hollow molded product after the hollow molding.

FIG. 5 is a side view showing one conventional mold portion for hollow molding.

[Explanation of symbols]

 1 1st metal mold part 2 1st bag cavity 3 Connection cavity 4 2nd bag cavity 10 2nd metal mold part 12 Parison 14 Piston 15 Cylinder 22 Connection part 30 Hollow molding

Claims (1)

(57) [Scope of utility model registration request] 1. A multi-bag container molding die structure in which a parison (12) is hollow-molded into a required shape by using a pair of openable and closable mold portions (1, 10). , 10) at least a first bag cavity (2) and a second bag cavity (4), a connection cavity (3) for connecting the respective cavities (2, 4), and the mold. A cylinder having a piston (14) that is provided in the parts (1, 10) and is configured to be able to move in and out
(15), and the piston (14) is the connection cavity
(3) A multi-bag container molding die structure, characterized in that it is configured so as to seal the connecting portion (22) of the hollow molded product (30) inside.