JP3348876B2 - Flexible container manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible container for accommodating or storing powder or granules, and more particularly to a manufacturing method suitable for mass production of such a flexible container.

[0002]

2. Description of the Related Art In general, as shown in FIG. 3, a flexible container of this type has a body portion 10 made of a flexible bag material and a central opening at the upper and lower ends of the body portion 10, respectively. It comprises a cylindrical inlet 12 and outlet 14 which are also made of a flexible bag material to be joined. Therefore, the flexible container thus configured can be appropriately folded when not in use, which is convenient for transportation and storage. In addition, reference numeral 16 indicates a hanging handle used during transportation.

[0003]

However, the conventional flexible container requires a complicated operation as described below in its manufacture, that is, in joining the inlet and the outlet to the body.

[0004] That is, the above-mentioned joint needs to have a sealing property against leakage of the contained matter and entry of foreign matter, and a joining strength against the load of the contained matter. Conventionally, however, the following welding method is adopted. It had been.

For example, as shown in FIG. 4, first, a cylindrical heating electrode mold 20 is inserted outside the cylindrical injection port 12, and the lower end 12a of the injection port 12 is connected to the heating electrode mold. The lower end portion of the injection port 12 is overlaid on the opening edge 10a of the central opening of the upper end surface of the body portion 10 by pulling it outward by a predetermined dimension from the lower end portion of the body 20. Thereafter, as shown in the figure, heating electrode molds 20 disposed vertically on both sides of the lower end 12a of the overlapped injection port 12 and the opening edge 10a of the body 10, respectively.
22 are pressed and contacted with each other to join the overlapped portions by welding. In this case, since the tip of the lower end portion 12a of the injection port 12 cannot be completely welded for the convenience of processing work, for example, it is coated in advance with a resin tape or the like, and is shown in FIG. As described above, the distal end of the lower end portion 12a is bent, and another heating electrode mold 24 is used in place of the heating electrode mold 20 to perform the joining by welding of the distal end portion. The same welding method is applied to the discharge port 14.

However, according to the conventional welding method,
Prior to the welding operation by the heating electrode molds 20 and 22, a manual operation for inserting a cylindrical heating electrode mold 20 having an inner diameter substantially the same as the outer diameter of the injection port 12 into the outside of the injection port 12 is performed. The lower end 12a of the entrance 12 is connected to the opening edge 1 of the body 10.
In order to overlap with 0a, it is necessary to perform manual operations for performing proper drawing and bending, and these manual operations are extremely complicated. Also, in the welding operation using the heating electrode dies 20, 22, when the pair of dies 20, 22 are pressed against each other, the lower end portion 1 of the injection port 12 is pressed.
In addition to the welding being performed while wrinkles are formed on the lower end 2a, it is necessary to perform the welding and bonding especially using the separate heating electrode mold 24 also on the front end portion of the lower end portion 12a. The number of such containers has increased, and there has been a problem in that the production of this type of container requires a lot of time.

SUMMARY OF THE INVENTION It is an object of the present invention to quickly and surely join an opening provided in a body to one end of a cylindrical inlet and outlet, and to improve the sealing performance of the joint. It is an object of the present invention to provide a method for manufacturing a flexible container capable of sufficiently securing bonding strength.

[0008]

In order to achieve the above object, a method for manufacturing a flexible container according to the present invention comprises:
A flexible body formed by joining the joining ends of a cylindrical inlet and an outlet, also made of a flexible bag material, to the central opening at the upper and lower ends of the body portion made of the flexible bag material. In the method for manufacturing a container, a heating electrode mold having an outer diameter substantially equal to the inner diameter of an inlet and an outlet is inserted into the central opening, and the edge of the opening is forcibly bent slightly outward. Then, one end of the inlet and the outlet is applied to the edge of the bent opening and overlapped with the edge, and thereafter, from the outside of the overlapped inlet and outlet. The overlapped portion is welded by pressing and pressing a heating electrode mold.

In this case, the opening diameter of the central opening of the body is set smaller than the inner diameter of the inlet and the outlet.

In the above-mentioned method for manufacturing a flexible container, the heating electrode mold inserted into the center opening of the body is fixed, and the edge of the opening and one end of the inlet and outlet are fixed. The heating electrode mold which presses and abuts from the outside of the injection port and the discharge port with respect to the overlapping portion with the above can be appropriately reciprocated while rotating in the circumferential direction.

[0011] The heating electrode mold inserted into the central opening of the body is rotated around the center axis together with the body, the injection port and the discharge port, so that the end of the opening is in contact with the edge of the opening. The heating electrode mold which presses and abuts from the outside of the inlet and the outlet to the overlapped portion with one end of the inlet and the outlet may be reciprocated as appropriate.

[0012]

According to the manufacturing method of the present invention, a heating electrode mold having an outer diameter substantially the same as the inner diameter of the inlet and the outlet is inserted into the center opening of the body, so that the edge of the opening is formed. Of the opening by forcibly bending it slightly outward, and then attaching one end of the inlet and the outlet to the edge of the bent opening. The inlet and one end of the outlet can be overlapped. Thereafter, by pressing and pressing the heating electrode mold from the outside of the overlapped injection port and discharge port, the overlapped portion can be welded simply and reliably.

[0013]

Next, an embodiment of a method for manufacturing a flexible container according to the present invention will be described in detail with reference to the accompanying drawings. 3 and 4 for convenience of explanation.
The same reference numerals are given to the same components as those in the conventional structure shown in FIG.

First, the structure of the flexible container applied to the manufacturing method of the present invention is the same as that of the above-mentioned conventional container. That is, in FIGS. 1 and 2, a flexible container is composed of a body 30 made of a flexible bag material, and a flexible bag joined to a central opening of the upper and lower end surfaces of the body 30, respectively. It comprises a cylindrical inlet 32 and an outlet (not shown, but configured exactly the same as the inlet 32) made of body material.

In this embodiment, however, as shown in FIGS. 1 and 2, the central opening 31 at the upper end surface of the body 30 has an outer diameter substantially equal to the inner diameter of the cylindrical inlet 32. A fixing heating electrode mold 34 having a cylindrical body and a frustum-shaped tip is inserted. In this case, as shown in FIG. 2, the opening 31 of the body 30 has an opening diameter dimension p smaller than the outer diameter dimension P of the fixing heating electrode mold 34, and the fixing heating electrode mold 34 has a smaller diameter. When inserting the electrode mold 34,
As shown in FIG. 1, a part of the edge 30a of the opening 31 is forcibly bent outward. In addition,
In this case, when a fiber-reinforced synthetic resin sheet is used as the flexible bag material, if the direction of the fibers is set as shown in FIG. 2, the bending process is easily performed by bias expansion of the fibers. be able to.

Next, the opening edge portion 30a of the body portion 30 into which the fixing heating electrode mold 34 has been inserted and bent.
A lower end portion 32a of the injection port 32 is attached to the outside thereof, and is overlapped with the edge portion 30a. Thereafter, as shown in FIG. 1, the moving heating electrode mold 36 is pressed and abutted on the outside of the lower end portion 12 a of the overlapped injection port 32, and the heating electrode mold 36 is fixed to the fixing heating electrode mold 34. Bonding is performed by welding the overlapped portions.

When the fixed heating electrode mold 34 and the moving heating electrode mold 36 are joined by welding the overlapped portion, the moving heating electrode mold 34 is fixed and the moving heating electrode mold 34 is fixed. The mold 36 alone is appropriately reciprocated while sequentially turning in the circumferential direction of the injection port 32,
This can be achieved by making contact with and separating from the overlapping portion. Further, as another method, for example, the heating electrode mold for fixing 34 is set so as to be pivotally driven about the center axis thereof together with the body portion 30 and the injection port 32, and the heating electrode mold for moving 36 is reciprocated as needed to be overlapped. It can also be made to contact and separate from the part.

In this embodiment, it is preferable that the edges of the opening of the inlet and the outlet of the outlet are covered with a resin tape or the like in advance, as in the prior art.

The preferred embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and many design changes can be made without departing from the spirit of the present invention.

[0020]

As described above, according to the method of manufacturing a flexible container according to the present invention, the flexible bag is also provided at the center opening of the upper and lower end surfaces of the body made of the flexible bag material. At the time of joining the joining ends of the cylindrical injection port and the discharge port made of a material, a heating electrode mold having substantially the same outer diameter as the inner diameter of the injection port and the discharge port is inserted into the central opening to open the opening. The edge of the opening is forcibly bent slightly outward, and then one end of the inlet and the outlet is attached to the edge of the bent opening and overlapped with the edge. Thereafter, the heating electrode mold is pressed against the outside of the overlapped injection port and discharge port to weld the overlapped portion, so that the joining of the overlapped portion is easier and faster than in the related art. Can be achieved. That is, according to the method of the present invention, the manual operation before the welding operation using the heating electrode mold is remarkably simplified, and the work efficiency can be improved and the sealing property and the joining strength of the welded joint can be sufficiently ensured. Therefore, according to the present invention, the effect of contributing to the improvement of the quality and the mass production of this kind of flexible container as well as its productivity is extremely large.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of a method for manufacturing a flexible container according to the present invention.

FIG. 2 is a schematic plan view showing a configuration of a central opening provided in a body used in the method for manufacturing a flexible container according to the present invention.

FIG. 3 is an external perspective view showing a general configuration of a flexible container.

FIG. 4 is a schematic cross-sectional view showing a conventional method for welding a joint portion of a flexible container.

FIG. 5 is a schematic sectional view showing a conventional method of welding a joint portion of a flexible container.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Body part 10a Edge part 12 Injection port 12a Lower end part 14 Outlet 16 Hanger 20 Core cylinder 20, 22, 24
Heating electrode mold 30 Body 30a Edge 31 Opening 32 Inlet 32a Lower end 34 Heating electrode mold for fixing 36 Heating electrode mold for movement

Claims (4)

(57) [Claims] 1. A joining end of a cylindrical inlet and a tubular outlet also made of a flexible bag material are respectively formed at upper and lower central openings of a body portion made of a flexible bag material. In the method for manufacturing a flexible container which is joined, a heating electrode mold having an outer diameter substantially equal to an inner diameter of an inlet and an outlet is inserted into the central opening, and an edge portion of the opening is slightly outward. Forcibly bend, then apply one end of the inlet and the outlet to the edge of the bent opening and overlap with the edge, and then the overlapped inlet and A method for manufacturing a flexible container, wherein a heating electrode mold is pressed and abutted from the outside of a discharge port to weld the overlapped portion. 2. The opening diameter of the central opening of the body is:
2. The method for producing a flexible container according to claim 1, wherein the diameter is set smaller than the inner diameter of the inlet and the outlet. 3. A heating electrode mold inserted into a center opening of a body portion is fixed, and a heating electrode mold is fixed to an overlapping portion of an edge of the opening and one end of an inlet and an outlet. 2. The method for manufacturing a flexible container according to claim 1, wherein the heating electrode mold pressed and contacted from the outside of the injection port and the discharge port is reciprocated as needed while rotating in the circumferential direction. 4. A heating electrode mold inserted into the central opening of the body is driven to rotate with the body, the inlet and the outlet about the central axis thereof, and the edge of the opening is in contact with the edge of the opening. 2. The method for manufacturing a flexible container according to claim 1, wherein the heating electrode mold which presses and abuts from the outside of the injection port and the discharge port with respect to the overlapped portion with one end of the inlet and the discharge port is reciprocated as appropriate.