GB2166122A

GB2166122A - Snap-action closures

Info

Publication number: GB2166122A
Application number: GB08525363A
Authority: GB
Inventors: Sally Margaret Langton
Original assignee: Schema Ltd
Current assignee: Schema Ltd
Priority date: 1984-10-17
Filing date: 1985-10-15
Publication date: 1986-04-30
Also published as: DE3537068A1; GB8525363D0; GB2166122B

Abstract

A body 1 and a hinged lid 2 therefor are formed as a one-piece moulding in plastics. the lid 2 having a snap-action to the open and closed positions characterised in that the moulding has a portion thereof adjacent the hinge 10 which promotes the snap-action, said portion, during opening or closing of the lid 2, reversing its configuration as it passes from an unstrained condition, through a strained condition, to a reversed unstrained condition. <IMAGE>

Description

SPECIFICATION Snap-action closures INTRODUCTION This invention relates to snap-action clo sures.

There are numerous types of containers such as bottles and the like which are de signed to hold fluids or granular materials and which are provided with a lid which may form part of the container itself or form part of a cap to be retained on the container. The lid in the closed position forms a seal with the container or cap and, when opened, permits the contents of the container to be dispensed.

It is particularly useful to be able to open or close the lid using only one hand and it is also useful for the lid to be retained in its open position during dispensing of the contents. For these reasons, it is known to so design the lid and container or cap that the lid has a snap-action to the open and closed positions.

OBJECT OF THE INVENTION It is the main object of this invention to provide a closure for a container which has a snap-action and which is of less complicated construction and which is cosmetically more suited to closures than hitherto designs.

STATEMENTS OF INVENTION According to the present invention there is provided a body and hinged lid therefor formed as a one-piece moulding in plastics, the lid having a snap-action to the open and closed positions, characterised in that the moulding has a portion thereof which promotes the snap-action, said portion, during opening or closing of the lid, reversing its configuration as it passes from an unstrained condition, through a strained condition, to a reversed unstrained condition.

The invention also includes a body and hinged lid therefor formed as a one-piece moulding in plastics, the lid having a snapaction to the open and closed positions by virtue of the hinge, characterised in that the hinge is a thin section defined by two unbroken lines each extending from one hinge end to the other.

DRAWINGS Figure 1 is a cross-sectional view through a closure constructed according to the invention; Figure 2 is a plan view of Fig. 1; Figure 3 is a scrap view looking in the direction of arrow Ill in Fig. 1; Figure 4 is a enlarged view of Fig. 3; Figure 5 is a cross-sectional view on the line V-V of Fig. 4; Figure 6 is a cross-sectional view on the line VI-VI of Fig. 4; Figure 7 is a cross-sectional view on the line VIl-VIl of Fig. 4; Figures 8 to 11 are diagrammatic cross-sectional views through the hinge part of a closure according to the invention; Figure 12 is a sectional view on the line XII-XII of Fig. 8; Figure 13 is a sectional view on the line XIll-Xlll of Fig. 11; Figures 14 to 16 are diagrammatic views equivalent to Figs. 8, 9 and 11 illustrating the snap-action; and Figures 17 to 19 are diagrammatic plan views in the direction of arrows A, B and C of Figs. 14, 15 and 16 respectively.

SPECIFIC DESCRIPTION Referring first to Figs. 1 and 2, a closure comprises a body 1 and a lid 2 all moulded as a one-piece unit in plastics. The body is a cap having a skirt 3 with internal nibs 4 which enable the cap to be attached to a bottle or other container with the skirt 3 outside the neck of the bottle and a plug 5 entering the neck to form a seal. The cap has a crown 6 with an opening 7 through which the contents of the bottle may be dispensed.

The lid 2 is dish-shaped with part 8 of the rim thereof projecting to enable the finger or thumb of the user of the bottle readily to open the lid when it is shut tight. Projecting from the base of the lid is a plug 9 which, when the lid is in the closed position, enters and seals the opening 7.

Joining the cap and lid is a hinge generally indicated at 10, the cap, lid and hinge all having been moulded in one-piece. It is the precise shape of this hinge 10 which enables the snap-action to be achieved and its precise shape will first be described with reference to Figs. 3 and 4.

Fig. 3 illustrates the hinge looking in the direction of arrow III in Fig. 1 and it will be noted that part of the hinge can be defined as two unbroken lines 11 and 12 which each extend from one end 13 to the other end 14 of hinge 10. The line 11 is straight (as viewed in the direction of arrow will) and the other line is an arc 12 of the circle centre 15 and radius 16. These two lines may both be curved when viewed in other directions. Indeed, the invention foresees that these two lines which define this part of the hinge may be of much more complicated shape.

For a more detailed description of the configuration of the hinge 10, reference will be made to Figs. 5, 6 and 7 and it will be seen that at the extremities 13 and 14 of the hinge part 10 (Fig. 7) the side wall 17 of the lid 2 merges naturally at 18 with the hinge part 10.

At the centre of the hinge part 10 (Fig. 5) there is present a distance of material-indicated at 19 in Fig. 4-which is not present at the hinge ends, this material progressively diminishing from the hinge centre to the hinge ends. An intermediate section between the centre and hinge ends is illustrated in Fig. 6.

To assist in understanding the manner in which the snap-action of the hinge 10 operates, reference is made to Figs. 8 to 19. In Figs. 8 to 11 a systematic representation of movement of the lid 2 from the open to the closed position is illustrated. In Fig. 8, the lid 2 is in the open position in relation to the closure 1 with the hinge 10 and that part 19 of the hinge which promotes the snap-action in an unstrained condition. It will be noted from Fig. 14 (which corresponds with Fig. 8) that the portion 19 of the hinge which promotes snap-action lies on one side of the theoretical hinge line 20. In Figs. 14 to 16, the centre of the portion which promotes snap-action is indicated at 21.

As the lid is moved from its fully open position as illustrated in Figs. 8 and 14 towards the closed position, it passes through the position illustrated in Figs. 9 and 15. The line 19 remains on the same side as the theoretical hinge 20 but the part 19 is strained and therefore deforms. A stage is reached when the position of the lid in relation to the position of the closure is such that the centre 21, in seeking to return to the unstrained condition of the hinge part 19, moves to the other side of the theoretical hinge 20, as illustrated in Fig. 10. The portion of the hinge which has been subjected to these forces, thus reverses its configuration.

Eventually, when the lid is in the fully closed position as illustrated in Figs. 11 and 16, the hinge part 19 is again in the unstrained condition.

Obviously, when the lid is moved from the closed to the open position, a similar although reversed set of conditions will apply.

It will thus be seen that when the lid is moved from the closed to the open position or from the open to the closed position, part of the hinge changes from an unstrained condition, through a strained condition-to provide the snap-action-and then to an unstrained condition, that part of the hinge which has been responsibe for the snap-action reversing its configuration during this movement.

Claims

1. A body and a hinged lid therefor formed as a one-piece moulding in plastics, the lid having a snap-action to the open and closed positions characterised in that the moulding has a portion thereof adjacent the hinge which promotes the snap-action, said portion, during opening or closing of the lid, reversing its configuration as it passes from an unstrained condition, through a strained condition, to a reversed unstrained condition.

2. A body and hinged lid therefor formed as a one-piece moulding in plastics, the lid having a snap-action to the open and closed positions by virtue of the hinge, characterised in that the hinge is a thin section defined by two notional lines each extending from one hinge end to the other, with the line 11 describing the axis of hinging.

3. A moulding according to Claim 2 in which one line maintains a fixed shape while the second line changes its shape during the snap-action.

4. A moulding according to Claim 2 or 3 in which one line is an arc which remains unchanged while the second line is a curve which changes its shape during the snap-action.

5. A moulding according to any one of claims 2 to 4, in which the distance of material between the two lines diminishes from the hinge centre to the hinge ends.

6. A moulding according to any one of claims 2 to 5 in which the size of the hinge section and the shape of the line of fixed shape are capable of forcing the portion of the moulding promoting snap-action to reverse its configuration during opening or closing of the lid.

7. A moulding according to any one of the preceding claims in which the portion promoting the snap-action forms part of the body of the moulding.

8. A moulding according to any one of the preceding claims in which the portion promoting the snap-action forms part of the lid of the moulding.

9. A moulding according to any one of the preceding claims in which the body forms a part or the whole of a container.

10. A moulding according to any one of claims 1 to 8 in which the body forms a part or the whole of a cap to be retained on a container.

11. A moulding substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.