METHOD OF MANUFACTURING A USABLE CONTAINER CONSISTING OF A STIFF OUTER CONTAINER AND A DEFORMABLE INNER BAG

Abstract

A method of manufacturing a usable container that includes supplying, by a first screw conveyor, a first thermoplastic plastic material for the outer container to an extruder, supplying, by at least one second screw conveyor, at least one second thermoplastic plastic material for the inner bag to the extruder, cutting at least two, preferably diametrically opposed, holes in the outer container at a lower edge region of a shoulder section, inserting pins vertically through the holes, between the inner bag and the outer container to loosen the inner bag from the inner wall of the outer container, exerting an increased pressure from an exterior through the holes onto the inner bag, or producing a reduced pressure in the inner bag to detach the inner bag from an inner wall of the outer container.

Claims

1. A method of manufacturing a usable container consisting of a stiff outer container and a deformable inner bag, the method comprising: supplying, by a first screw conveyor, a first thermoplastic plastic material for the outer container to an extruder; supplying, by at least one second screw conveyor, at least one second thermoplastic plastic material for the inner bag to the extruder, which coextrudes a preform, which is arranged between the open halves of a blow mold of a blow molder, wherein the blow mold is closed when the preform has a length necessary for the manufacture of the container, wherein excess material in a base region of the container to be manufactured is squeezed out and a web is formed from material of the outer container, in which the welded base seam of the inner bag is clamped, and wherein the preform is inflated by a pressure medium into engagement with the wall of the blow mold, the excess material beneath the weld seam is severed and the container is removed from the blow mold; cutting at least two, preferably diametrically opposed, holes in the outer container at a lower edge region of a shoulder section; inserting pins vertically through the holes, between the inner bag and the outer container to loosen the inner bag from the inner wall of the outer container; exerting an increased pressure from an exterior through the holes onto the inner bag, or producing a reduced pressure in the inner bag to detach the inner bag from an inner wall of the outer container.

2. A method as claimed in claim 1, wherein the pins are introduced a short distance of about 5 to 15 mm between the inner bag and the outer container.

3. A method as claimed in claim 1, wherein the pins are used with rounded head ends.

4. A method as claimed in claim 1, wherein an increased pressure is applied externally.

5. A method as claimed in claim 1, wherein a reduced pressure is applied in the inner bag.

6. A method as claimed in claim 1, wherein the cutting and inserting are performed in a cutting station of a detaching machine.

7. A method as claimed in claim 1, wherein the producing is performed in a detaching station of the detaching machine.

8. A method as claimed in claim 1, wherein the detaching machine is connected to the blow molder so that containers which are still warm may be further processed in the detaching machine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1A is a side view of an outer container 1 with a hole 3 cut in the outer container 1 at the lower edge region of the shoulder section 2. The sectional view B-B of FIG. 1B shows that two such holes 3 are cut situated diametrically opposite to one another in the lower edge region of the shoulder section 2. An ejector pin 4 is shown above the holes 3 in a starting position. In FIG. 2A, the pin 4 is advanced through a hole between the inner bag and the outer container, whereby the inner bag is detached in this region from the inner wall of the outer container. This is shown in the sectional view A-A of FIG. 2B.

DETAILED DESCRIPTION

[0017] FIG. 1A is a side view of an embodiment of an outer container.

[0018] FIG. 1B is a cross-sectional view of the outer container of FIG. 1A taken along line B-B in the direction generally indicated.

[0019] FIG. 2A is a side view of the outer container of FIG. 1A having a pin advanced through a hole between an inner bag and the outer container.

[0020] FIG. 2B is a cross-sectional view of the outer container of FIG. 2A taken along line A-A in the direction generally indicated.