GB2042461A

GB2042461A - Improved transport container

Info

Publication number: GB2042461A
Application number: GB7907088A
Authority: GB
Original assignee: BLOWMOULDERS Ltd R
Current assignee: BLOWMOULDERS Ltd R
Priority date: 1979-02-28
Filing date: 1979-02-28
Publication date: 1980-09-24
Also published as: GB2042461B

Abstract

In order to provide a readily obtained large aperture, e.g. for insertion of an agitator, a blow moulded plastics drum (1) or similar container is provided with a zone 5 having a peripheral groove 6 by which the wall thickness is reduced to a value, e.g. 1.5 to 2.5 mm, which can be cut by a knife. The groove 6 may be formed by machining or it may be moulded-in. Beads 7 are provided by receive a snap-on closure. <IMAGE>

Description

SPECIFICATION Improved transport container This invention relates to transport containers, particular for liquids.

Such containers, particular in the form of drums, e.g. of 25 litre or similar capacity, are frequently used only for one journey so that their manufacturing cost has to be kept low.

With certain types of liquids, e.g. those with material in suspension therein, such as dyestuffs, it is necessary for the liquid to be mechanically stirred or agitated before it is poured out from its transport container, e.g. a drum.

The filling and pouring aperture of such a container has to be readily cleaned and tightly sealed, usually by a separate moulded screwin stopper and for reasons of design this is kept as small as possible. Accordingly, the aperture is not normally large enough for access by a suitable agitator and accordingly a further readily opened access point has to be provided. Hitherto, this has been provided by an opening, e.g. 15 cm in diameter, covered in a foil laminate secured by hot plate welding to a surrounding area of the container and covered by a snap-on cap. The laminate can be cut away with a knife for ready access to the contents of the container by an agitator or stirrer and the snap-on cap can be replaced to provide a temporary closure if the whole contents of the container are not required for immediate use.The use of a foii has the advantage that it can be readily cut by a knife so that no swarf is formed, which might find its way into the liquid within the container.

However, this procedure is expensive since with the usual blow-moulding process for such containers, the opening normally has to be cut by a separate operation and the cutting and welding operation of the laminate also leads to considerable cost and use of material.

It is now proposed, according to the invention, to provide a line of weakness, in the form of a groove for ready identification, in which the wall thickness is reduced around the required aperture to such an extent that the plastics material can be cut by hand using a knife. The groove may be formed by a machining operation or it may be moulded in.

In the preferred application of the invention, the container is blow moulded, but it will be appreciated that the invention is also applicable to containers made by other forms of moulding such as rotational moulding.

The invention will be further described with reference to the accompanying drawing, which shows a currently preferred embodiment of the invention, and in which: Figure 1 is a plan view a form of container to which the present invention has been applied; Figure 2 is a section, to an enlarged scale, taken along the line ll-ll of Fig. 1; and Figure 3 is a section, to the same scale as Fig. 2, taken along the line Ill-Ill of Fig. 1.

Fig. 1 shows a drum 1 which is blow moulded within a mould formed of two halves which come together along a line indicated at 2 in Fig. 1. The drum has a conventional filling and pouring aperture 3 which is bisected by the parting line 2, and is also provided with an eye 4 to receive a separate moulded carrying handle. The aperture 3 is threaded to receive a separately moulded threaded stop. It will be seen that this aperture is comparatively smail for reasons of economy security of sealing.

In order to provide a larger aperture for access to the content of the drum by mechanical agitator or other stirring device, a central disc 5, is provided. The wall thickness of this central disc is a conventional thickness as arises in blow moulding, e.g. 4 mm or more and in the region of the parting line 2, as indicated by Fig. 3, it is considerably greater than over the rest of its area, the thickness of which is shown in Fig. 2. In order to make the disc 5 readily removable without recourse to heavy cutting tools such as saws, which would generate swarf which might pollute the material carried within the drum 1 the disc 5 is provided with a peripheral groove 6 so that the wall thickness to the bottom of the groove is reduced to such an extent that the plastics material can be readily cut with a sharp knife.

A typical thickness is between 1 mm and 2.5 mm. It will be seen that in the region of the parting line 2, as illustrated in Fig. 3, the groove 6 is considerably deeper than in the section shown in Fig. 2 and this deeper section is illustrated at 6a in Fig. 1.

The groove 6 may be formed by a machining operation by presenting the drum 1 at an appropriate orientation to a tool pre-programmed to cut to the required depth and vary it in the region of the parting line 2 to provide the deeper zones 6a.

As an alternative, an appropriate formation may be provided on the mould halves within which the drum is originally moulded.

It will be seen from Figs. 1 and 3 that peripheral beads 7 are provided to receive a snap-on cap which normally covers the disc 5 and may be used, after the disc 5 has been replaced to provide temporary closure of the drum 1.

Various modifications may be made within the scope of the invention.

1. A container of plastics material having a readily removable zone in a wall thereof to allow access to the contents of the container, in which a peripheral portion of the said zone is formed with a groove so as to reduce the wall thickness at the groove to such an extent that the plastics material may be cut by hand

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improved transport container This invention relates to transport containers, particular for liquids. Such containers, particular in the form of drums, e.g. of 25 litre or similar capacity, are frequently used only for one journey so that their manufacturing cost has to be kept low. With certain types of liquids, e.g. those with material in suspension therein, such as dyestuffs, it is necessary for the liquid to be mechanically stirred or agitated before it is poured out from its transport container, e.g. a drum. The filling and pouring aperture of such a container has to be readily cleaned and tightly sealed, usually by a separate moulded screwin stopper and for reasons of design this is kept as small as possible. Accordingly, the aperture is not normally large enough for access by a suitable agitator and accordingly a further readily opened access point has to be provided. Hitherto, this has been provided by an opening, e.g. 15 cm in diameter, covered in a foil laminate secured by hot plate welding to a surrounding area of the container and covered by a snap-on cap. The laminate can be cut away with a knife for ready access to the contents of the container by an agitator or stirrer and the snap-on cap can be replaced to provide a temporary closure if the whole contents of the container are not required for immediate use.The use of a foii has the advantage that it can be readily cut by a knife so that no swarf is formed, which might find its way into the liquid within the container. However, this procedure is expensive since with the usual blow-moulding process for such containers, the opening normally has to be cut by a separate operation and the cutting and welding operation of the laminate also leads to considerable cost and use of material. It is now proposed, according to the invention, to provide a line of weakness, in the form of a groove for ready identification, in which the wall thickness is reduced around the required aperture to such an extent that the plastics material can be cut by hand using a knife. The groove may be formed by a machining operation or it may be moulded in. In the preferred application of the invention, the container is blow moulded, but it will be appreciated that the invention is also applicable to containers made by other forms of moulding such as rotational moulding. The invention will be further described with reference to the accompanying drawing, which shows a currently preferred embodiment of the invention, and in which: Figure 1 is a plan view a form of container to which the present invention has been applied; Figure 2 is a section, to an enlarged scale, taken along the line ll-ll of Fig. 1; and Figure 3 is a section, to the same scale as Fig. 2, taken along the line Ill-Ill of Fig. 1. Fig. 1 shows a drum 1 which is blow moulded within a mould formed of two halves which come together along a line indicated at 2 in Fig. 1. The drum has a conventional filling and pouring aperture 3 which is bisected by the parting line 2, and is also provided with an eye 4 to receive a separate moulded carrying handle. The aperture 3 is threaded to receive a separately moulded threaded stop. It will be seen that this aperture is comparatively smail for reasons of economy security of sealing. In order to provide a larger aperture for access to the content of the drum by mechanical agitator or other stirring device, a central disc 5, is provided. The wall thickness of this central disc is a conventional thickness as arises in blow moulding, e.g. 4 mm or more and in the region of the parting line 2, as indicated by Fig. 3, it is considerably greater than over the rest of its area, the thickness of which is shown in Fig. 2. In order to make the disc 5 readily removable without recourse to heavy cutting tools such as saws, which would generate swarf which might pollute the material carried within the drum 1 the disc 5 is provided with a peripheral groove 6 so that the wall thickness to the bottom of the groove is reduced to such an extent that the plastics material can be readily cut with a sharp knife. A typical thickness is between 1 mm and 2.5 mm. It will be seen that in the region of the parting line 2, as illustrated in Fig. 3, the groove 6 is considerably deeper than in the section shown in Fig. 2 and this deeper section is illustrated at 6a in Fig. 1. The groove 6 may be formed by a machining operation by presenting the drum 1 at an appropriate orientation to a tool pre-programmed to cut to the required depth and vary it in the region of the parting line 2 to provide the deeper zones 6a. As an alternative, an appropriate formation may be provided on the mould halves within which the drum is originally moulded. It will be seen from Figs. 1 and 3 that peripheral beads 7 are provided to receive a snap-on cap which normally covers the disc 5 and may be used, after the disc 5 has been replaced to provide temporary closure of the drum 1. Various modifications may be made within the scope of the invention. CLAIMS

1. A container of plastics material having a readily removable zone in a wall thereof to allow access to the contents of the container, in which a peripheral portion of the said zone is formed with a groove so as to reduce the wall thickness at the groove to such an extent that the plastics material may be cut by hand using a knife.

2. A container as claimed in claim 1, in which the wall thickness at the base of the groove is between 1 mm and 2.5 mm.

3. A carrier as claimed in claim 1 or 2, in which the container is formed by a blow moulding operation.

4. A container as claimed in claim 3, in which mould halves used to form the container have left an area of increased wall thickness running across the said zone, and in which the groove is made deeper where it crosses the said area of increased wall thickness.

5. A container as claimed in any of the preceding claims, in which the groove is formed by a machining operation after moulding.

6. A container substantially as hereinbefore described with reference to the accompanying drawing.

6. A container as claimed in any of claims 1 to 4, in which the groove is moulded-in.

7. A container substantially as herein be fore described with reference to the accompanying drawing.

CLAIMS (8 April 1980)

1. A container blow moulded of plastics material and having a readily removable substantially planar zone in a wall thereof to allow access to the contents of the containers, in which a peripheral portion of the said planar zone is formed with a groove so as to reduce the wall thickness at the groove to such an extent that the plastics material may be cut by hand using a knife.

3. A container as claimed in claim 1 or 2, in which mould halves used to form the container have left an area of increased wall thickness running across the said zone, and in which the groove is made deeper where it crosses the said area of increased wall thickness.

4. A container as claimed in any of the preceding claims, in which the groove is formed by a machining operation after moulding.

5. A container as claimed in any of claims 1 to 3, in which the groove is moulded-in.