GB2041891A

GB2041891A - Container Closures

Info

Publication number: GB2041891A
Application number: GB7904381A
Authority: GB
Original assignee: Bakelite Xylonite Ltd
Current assignee: BXL Plastics Ltd
Priority date: 1979-02-07
Filing date: 1979-02-07
Publication date: 1980-09-17
Also published as: GB2041891B

Abstract

A closure moulded from plastics materials or plastics laminated foil comprises a wall (8) having an aperture (10), and an integrally formed bar (18) adapted for pivotal movement about a flexible hinge (16) the bar being provided with a plug (20) which on closing enters the aperture (10), the plug acting to clear the aperture of residual material dispensed from the container. <IMAGE>

Description

SPECIFICATION Container Closures The invention relates to containers and closures therefor.

Containers intended to be used to store and dispense flowable liquids powders or pasty material, for example toiletry materials such as creams and lotions, are required to have closure means capable of resealing the dispensing aperture thereof a large umber of times during the use of the container. It is also advantageous if the closure and its resealing means are integral with one another so as to avoid the risk of mislaying a portion. thereof. It has been suggested that a closure means moulded from plastics material may comprise a plug attached to the closure member by means of a strip or finger of plastics material, the closure being achieved by deforming the web or finger so that it permits the plug to enter the aperture.As a subsequent step to the manufacture of the closure means, accurate deformation of the strip so that the plug is aligned with the aperture for ease of entry, is a relatively costly matter.

It is also necessary that the plug is an efficient seal to prevent undue degradation of the flowable material due to contact with the air.

The invention therefore provides a closure means for a container, said closure means being moulded from suitable plastics material, and comprising a wall member having an aperture therein, an integrally formed bar portion adapted for pivotal movement about a flexible hinge portion the bar portion being provided with a plug member at a region spaced from the hinge portion by a distance similar to the distance between the aperture and the hinge portion, the plug being adapted to enter and occupy the aperture in a closing condition, the plug acting to clear the aperture of residual material dispensed from the container.

Advantageously, the plug is provided with an end portion having projection(s) or shoulders to that these engage the underside of the wall member in the region of the lips of the aperture to assist in the retention of the plug in place in the aperture.

In examples of containers having closure means as described in accordance with the invention, the container and the wall member of the closure means are formed integrally with one another, the container being in the form of a tube having either flexible or rigid walls. The walls may be formed of any suitable plastics material or from plastics laminated foil. The wall member of the closure means provides an end wall of the tube which may be crimp-closed at its opposite end in a conventional manner after filling. Alternatively, the open end may be provided with a suitable plug.

It is advantageous if the closure means is manufactured using a moulding technique in which the plug-bearing bar member is formed in a position perpendicular to the plane of the wall member by the supply of molten plastics material into a cavity defined by a plurality of mould members. A subsequent manufacturing step involves moving the bar member pivotally about the plastics hinge so that the plug automatically enters the aperture, An example of the manufacture of a container with a closure member according to the invention will now be described with reference to the accompanying drawings.

It will be understood that thadescription is given by way of example only and not by way of limitation of the invention. ~ In the drawings:~ Figure 1 is a side view partly in cross-section of a a container with a closure means in an open condition; Figure 2 is a similar view to Figure 1 showing the closure means in a closed condition; Figure 3 shows a top view of the container of Figure 2; Figure 4 shows a vertical section through a mould arrangement suitable for making the container and closure means of Figures 1 and 2.

Figure 1 shows a container 2 having flexible side walls 4 integrally formed with a ciosure means 6 including an end wall member 8. An aperture 10 comprising an outlet for the contents of the container when manual pressure is applied to the walls 4. The aperture is provided in a first portion 12 of the wall member 8 which is recessed compared with the main portion 14. A flexible plastics hinge 16 is formed along a portion of boundary region of the portions 12 and 14, and provides for pivotal movement of a bar member 18 between an open position shown in Figure 1 and a closed position shown in Figure 2 in which a plug member 20 on the bar member 18 enters the aperture 10. The distances between the plug member 20 and the hinge 16 and between the aperture 10 and the hinge 16 are such that the plug is automatically aligned with and enters the aperture in the closing operation.

The plug member 20 is of a length greater than the depth of the aperture 10 so that an end portion 22 projects into the chamber of the container. This end portion 22 is provided with a projecting ridge 24 which engages with the underside of the wall member portion 12 at the lip of the aperture to assist in retaining the closed position.

It will be appreciated that the flexible nature of the plastics material from which the closure means is moulded permits the plug to be forced into the aperture fairly easily and in entering and occupying the aperture, it effectively clears it of residual material which may otherwise degrade, resulting in its unsightly appearance the next time the container is used.

An outer end portion of the bar member will be seen from Figure 2 to project from the recessed wall portion 12. This facilitates opening of the closure means by finger-tip pressure in the direction of arrow A.

An example of a moulding assembly suitable for use in the manufacture of the above closure will now be described. Figure 4 shows a composite moulding device comprising a core portion 26 on which is supported a length of polythene tubing 28 in the manner of a mandrel.

An outer mould member 30 surrounds the core 26 and clamps against the tubing 28.

A further mould member comprising two abutting portions 32, 34 are supported by the mould member 30 so that sloping surfaces 35 are pressed firmly against complementary sloping surfaces 36 of a third mould member 38 which surrounds an inlet member 40 for a nozzle of an injection moulding machine (not shown).

Although the two portions 32 and 34 are normally spring-biassed apart, their arrangement so that they abut one another under pressure results in the virtual absence of the formation of flash.

Thus a mould cavity is formed into which polythene is injected so as to form a closure means for the tubing 28 to the edge of which it fuses to produce an integral construction.

When the moulding operation is complete, the mould members are released, the abutting portions 32, 34 moving apart under the influence of springs (not shown) and the surfaces 35 sliding with respect to the surface 36 to free the newly moulded bar member 18 and allow the cone member 26 to be withdrawn.

The core merflber 26 is provided with a springbiassed rod 42 which projects into the mould cavity to form the aperture 10. When the core and the rod are removed from the moulding, the next step in the manufacturing process is to close the aperture 10 by pivotally moving the bar member 18 about the hinge so that the plug 20 enters the aperture. This may be achieved by a suitable reciprocating-pressure applying device since no special alignment is required.

Claims

Claims

1. A closure means for a container, said closure means being moulded from suitable plastics material, and comprising a wall member having an aperture therein, an integrally formed bar portion adapted for pivotal movement about a flexible hinge portion the bar portion being provided with a plug member at a region spaced from the hinge portion by a distance similar to the distance between the aperture and the hinge portion, the plug being adapted to enter and occupy the aperture in a closing condition, the plug acting to clear the aperture of residual material dispensed from the container.