WO1987007241A1

WO1987007241A1 - A collapsible container

Info

Publication number: WO1987007241A1
Application number: PCT/FI1987/000066
Authority: WO
Inventors: Svjatoslaf Gratschew; Pekka Piippo; Matti MÄKINEN; Markku Santala
Original assignee: Piippo Oy
Priority date: 1986-05-21
Filing date: 1987-05-14
Publication date: 1987-12-03
Also published as: EP0305392A1; FI75536B; FI75536C; DK21688D0; DK21688A; FI862130A0; FI862130L

Abstract

Container, such as a barrel, made of a fibrous material, which container comprises a body (1) and a cover and a bottom plate (2, 3) fastened detachably to the body by means of hoops (4). The storing and transporting of empty barrels is expensive due to the fact that they require plenty of room. This disadvantage can be eliminated by providing the body (1) with an axial slit (7) and a hinge (8) extending in the same direction as and opposite to the slit, around which hinge body portions (9, 10) can be turned to an open position for transportation.

Description

A collapsible container

This invention relates to a collapsible container comprising a tubular body made of wound paperboard and comprising an axial slit and an axial hinge dividing the body into two curved portions, end plates closing the ends of the body; and means for detachably fastening the end plates to the ends of the container. The invention is also concerned with a method for the manufacture of the container. Various bulk goods such as powder-like metallurgical products are often transported and stored in barrels the body of which is made of wound paper and the cover and bottom plates of a plastic or fibrous board. The outer surface of the body is provided with a groove adjacent to the edges, by means of which groove the cover and the bottom plate can be fastened to the body with a hoop having a U-shaped cross-section. The hoop which fastens the cover plate is provided with locking means by means of which the cover plate can be fastened detachably to the body, whereas the hoop of the bottom plate is generally fixed. Barrels of this type are light and durable. Due to their high price they are not disposable but are returned to the sender after they have been emptied. It is obvious that such return transports increase considerably the total cost of the package, and the same naturally applies to the storing of empty barrels.

U.S. Patent Specifications 3 064 870 and 3 982 681, for instance, disclose containers intended for reducing the return costs. In these containers the tubular body is formed by two curved portions. The axial edges of the body portions are provided with means for interconnecting the portions to form a container. In U.S. Patent Specification 3 064 870 these means are formed by hinges by means of which the body portions can be interconnected and which also allow the body to be opened by turning the portions around the pin of one of the hinges. The transport of such known containers when empty- is extremely cheap, because the body portions can be de- tached from each other and piled one upon another similarly as the end plates. However, the containers also have a few disadvantages. They are complicated in construction; this concerns the hinges in particular, since the hinge halves have to be fixed firmly to the body and the hinges require separate hinge pins for locking the body portions to each other. The hinge halves are usually fastened to the body portions by means of rivets extending through the wall of the body, which naturally deteriorates the strength of the body. The leakproofness of the container may also deteriorate in the long run adjacent to the hinges after the container has been disassembled and assembled many times. The object of the present invention is to provide a collapsible container which is simpler and more durable than corresponding known containers. The container according to the invention is characterized in that the hinge is a score formed in the wall of the body. By providing the body with a score acting as a hinge a major advantage is obtained in that the tubular body of the container can be made of a single piece so that the hinge means used in known containers can be omitted. The body can be locked into a tubular shape by means of hoops provided with locking means so that the walls of the body do not need to be pierced with rivets. In addition, the container according to the invention is more steady than known containers, since the body is formed of a single piece instead of two, as in prior containers. Also, it is obvious that the hinge according to the in- vention is considerably simpler and cheaper to manufacture than hinges used previously in this type of barrels.

The score performs the function of a hinge in the best possible way if it is formed by an inwardly curved body zone; however, in large containers in particular the score may advantageously be curved outwards.

According to the invention it is essential to the durability of the container that the score is substantially perpendicular to the fibre direction of the paperboard so that the fibres of the paperboard extend in the transverse direction of the score, by virtue of which the score withstands a great number of bendings.

The invention is also concerned with a method for the manufacture of a collapsible container, in which method a paper web is wound into a tubular paperboard body, the body is split in the axial direction and provided with an axial hinge in order to form two curved body portions, and the container is provided with end plates and means for detachably fastening the end plates to the ends of the container.

The method according to the invention is characterized in that the body is provided with a hinge by forming an axial score in the body.

One preferred embodiment of the container according to the invention will be described in the following in more detail with reference to the attached drawing, wherein

Figure 1 is an axonometric view of a barrel according to the invention.

Figure 2 is a perspective view of the opened body, and

Figure 3 is a cross-sectional view of the body in the area of the hinge.

Figure 1 shows a cylindrical barrel comprising a tubular body 1 made of a fibrous material, such as wound paperboard, the ends of the body being closed by means of a cover plate 2 and a bottom plate 3. The body is preferably made of a so called kraftliner paperboard comprising e.g. twelve paper layers glued together, as a result of which the wall of the body is substantially rigid. The thickness of the wall is, for instance, about 4 mm. The plates 2, 3 are fastened to the body by means of hoops 4 having U-shaped cross-section the edges of which extend on to the outer surface of the plates and into a groove formed on the outer surface of the body by means of a metal band 5. The hoops 4 are cut off at one point, and a locking means 6 is provided at this point for slackening off and tightening the hoop.

The body 1 is provided with an axial slit 7 extending from end to end. In other words, the body is split at one point over the whole length thereof. A hinge 8 is formed on the other side of the body, opposite to the slit 7. The metal bands 5 are cut off at the slit 7 and at the hinge 8.

The slit 7 and the hinge 8 divide the body into two body portions 9 and 10 equal in width and having a semi-circular cross-section. These body portions are provided with locking means at the slit 7 for interconnecting the body portions 9, 10 over the slit 7 when the container is in the assembled condition. A locking plate 12 is provided, at the free axial edge of the body portion 10, which plate extends beyond the edge and is fastened to the inner surface of the body e.g. by means of clasps.

According to the invention the hinge of the body is a score 8 formed in the paperboard; in the embodiment described the score is formed by an inwardly curved body zone, see Figure 3. The body is thus formed of one relatively rigid piece of paperboard which can be bent at a point opposite to the slit 7 by virtue of the score 8. The paper layers forming the body are wound in the peripheral direction so that the score is substantially perpendicular to the fibre direction of the paperboard.

The container according to the invention functions in the following way. When a full container arrives at its destination, the locking means 6 is released, so that the cover plate 2 and, if desired, also the hoop 4 attached thereto can be detached from the container. After the container has been emptied, the lower locking means 6 is released and the hoop and the bottom plate 3 are detached. Thereafter the locking means 11 are released, so that the body portions 9, 10 can be turned around the score 8 to a position shown in Figure 2, in which the portions are positioned side by side. A desired number of bodies so opened can be piled one upon another. The container is returned to the sender with the body in the position shown in Figure 2.

When the container is reassembled, the body 1 is closed, so that the locking plate 12 is positioned at the slit 7 on the inner surface of the body. The locking means 11 are closed, and the cover and the bottom plate 2, 3 are fastened in place by means of the hoops 4 and the locking means 6.

The container according to the invention is manufactured by winding a paper web in several layers around a roll into a tubular paperboard body, whereafter the body is split in the axial direction and a score 8 is pressed in the wall of the body opposite to the splitting point. The container is also provided with end plates 2, 3, hoops 4 for fastening the end plates to the body and locking means 11 for locking the container in the assembled condition. It is essential to the invention that the paper web is wound on the roll in the peripheral direction in order that the fibres in the paper would be positioned transversely with respect to the score 8. It is to be noted that because both the cover and the bottom plate are fastened detachably, the volume of the container can be increased by placing two or more bodies 1 upon each other. The bodies are thereby fastened to each other by means of hoops extending from one groove of the body to a corresponding groove in the adjacent body. Consequently, the locking means 11 can be fastened to the body or, alternatively, they can be positioned in the hoops which extend around the body. The latter alternative has the advantage that the wall of the body does not thereby need to be pierced with rivets or the like. In order to simplify the transport of the container, parallel boards can be fastened on the outer surface of the lower end plate 3 so that the container can be lifted by means of a truck fork. The lower end plate thereby functions as a pallet.

Claims

Claims:

1. A collapsible container comprising a tubular body (1) made of wound paperboard and comprising an axial slit (7) and an axial hinge (8) dividing the body into two curved portions (9, 10); end plates (2, 3) closing the ends of the body; and means (4) for detachably fastening the end plates to the ends of the container, c h a r a c t e r i z e d in that the hinge is a score (8) formed in the wall of the body.

2. A container according to claim 1, c h a r a c te r i z e d in that the score (8) is formed by an inwardly or outwardly curved body zone.

3. A container according to claim 1, c h a r a c te r i z e d in that the score (8) is substantially perpendicular to the fibre direction of the paperboard.

4. A container according to claim 1, in which the end edges of the body are shaped by means of a metal band (5), c h a r a c t e r i z e d in that the metal bands (5) are cut off at the slit (7) and at the score (8) of the body.

5. A container according to claim 1, c h a r a c te r i z e d in that a locking plate (12) is provided at the free axial edge of one (10) of the body portions, which plate extends beyond the edge and is fastened on the inner surface of the body (1).

6. A container according to claim 1, c h a r a c te r i z e d in that parallel boards are provided on the outer surface of the lower end plate (3) for forming a pallet.

7. A method for the manufacture of a collapsible container, wherein a paper web is wound into a tubular paperboard body (1), the body is split in the axial direction and provided with an axial hinge (8) for the formation of two curved body portions (9, 10), and the con tainer is provided with end plates (2, 3) and with means (4) for fastening said end plates detachably to the ends of the container, c h a r a c t e r i z e d in that the body (1) is provided with a hinge by forming an axial score (8) in the body.

8. A method according to claim 7, c h a r a c t e r i z e d in that the score (8) is formed in the body by pressing a body zone inwards or outwards in such a manner that the obtained score has a curved cross-section,

9. A method according to claim 7, c h a r a c t e r i z e d in that a paper web is wound into a tubular body so that the fibres of the web are positioned substantially perpendicular to the score (8).