Bottle Cap

Abstract

One piece plastic bottle cap is characterized by a reinforcing ring which projects below the external skirt of the cap and has a frusto-conical external profile which decreases in radius toward the bottom. It is particularly adapted to capping bottles containing carbonated liquids or deformable bottles of plastic material.

Description

SUMMARY OF THE INVENTION

This invention relates to a new type of telltale bottle cap which is made in one piece from plastic material and provided with a reinforcing ring for its retaining ring, which may be used as a removing ring after breaking the webs connecting said reinforcing ring to the outer skirt of the cap, which webs are positioned opposite a hinge connecting these two components.

Other types of telltale bottle caps which are particularly adapted for containers holding carbonated beverages have been described in various French patents. These prior devices have disclosed the provision of weakened areas in the retaining ring for these caps and also in the cap itself so as to cause tearing of the cap during removal thereof, which tears constitute visible evidence of prior opening when the caps are replaced on the bottles.

The new type of telltale cap according to the present invention comprises various improvements making it possible to eliminate certain disadvantages of the prior art devices.

One of these improvements resides in the fact that the reinforcing ring, the radial thickness of which is at its maximum at the top of said hinge and of said retaining ring extends downwardly below the retaining ring and tapers to a decreased thickness at its lower edge. The thickness at the bottom of the ring is as thin as possible and the lower edge of the reinforcing ring is so close to an external enlargement of the neck of said bottle beneath the groove cooperating with said retaining ring as to make it impossible to remove the cap by exerting pressure against the lower part of this reinforcing ring on the same side as said hinge so as to avoid breaking the connecting webs. This new arrangement thus eliminates one of the methods used to circumvent previously known devices.

Another characteristic of the cap is that, on the side remote from the hinge, where it is necessary to act on the ring to rupture the connecting webs, so as to use the reinforcing ring as a cap-removing ring, there is either a recess, which is preferably ribbed, formed in this ring, or a horizontally projecting ridge having a variable radial thickness in the form of an arc or cross so as to facilitate the swinging of said ring.

This recess may advantageously have at its top a horizontal flat portion having a radial thickness sufficient to constitute an effective fingerhold for the finger of the operator, which makes it possible to use less material than in the case of the horizontal rib previously mentioned.

Another possible characteristic of the new one-piece cap resides in the provision of notches in the lower part of the reinforcing ring on opposite sides of the hinge which prevent the remounting of this ring in a horizontal position after normal cap removal. This ring remains, on the contrary, a little raised on the side opposite the hinge with an oblique orientation constituting a readily visible indication that the bottle has already been opened.

As a consequence of the elimination of the possibility of fraud the scorings provided in the embodiments heretofore described, and the use of a retaining ring having a variable thickness, have been eliminated so as to permit a better retention of the cap on the bottle by the combined action of the retaining ring and its reinforcing ring.

In order to obtain a better internal seal with the cap it has already been proposed to provide an internal skirt having two walls of different thickness, the outermost of which cooperates with the inside of the neck of the bottle and is provided at its lower part with a rib forming a sealing member and affording on the other hand, at the top of the neck of the bottle the possibility of inserting between the external skirt of the cap and the internal skirt of compressible plastic sealing member made, for example, of a plastisol and capable of increasing this internal fluid tightness.

In one of the embodiments of the invention the applicant has provided a simple internal sealing skirt having a single wall provided at its lower part with a deformable incurved bottom edge and a lip normally inclined toward the center which can be straightened toward a vertical position so as to be pressed against the neck of the bottle during the closing of the bottle, the internal skirt having an external diameter substantially greater than the internal diameter of the said bottle so that it cannot be inserted in the neck except by exerting a force on the bottom of said skirt sufficient to simultaneously modify the curvature of the bottom, the external diameter of the skirt and the orientation of said lip.

Moreover the said lower incurved part is connected with the lip by a neck facilitating the straightening of the lip into a vertical position in alignment with the upper part of this skirt.

In another embodiment the incurved bottom is eliminated and replaced by a flat part of substantially constant thickness closing said sealing skirt at its upper end in which case the height of the skirt is such that its lower part terminates beyond the lower part of the external skirt carrying the retaining ring.

This external skirt itself preferably extends downwardly beyond the retaining ring so as to improve the effectiveness of the reinforcing ring before it is swung to permit it to serve as a removing ring, and also to permit an increase in the thickness of material in the neighborhood of the hinge and consequently the strength of the connection between the removing ring and the cap proper, the upper part of which connection is limited at the top of the retaining ring to facilitate its swinging.

The internal sealing skirt provided in the second embodiment is generally cylindrical in shape and has a lower part of reduced thickness which permits the more ready introduction of said skirt into the inside of the neck, and a thicker upper part which can be inserted in said neck only by the application of considerable force so as to insure the necessary seal and permit this cap to resist the pressure of the gases contained in the bottle being closed by said cap. The two parts of the internal sealing skirt have different thicknesses, and while the internal wall of said skirt is generally cylindrical, the two parts are connected to each other by an externally frusto-conical portion positioned preferably at the level of the retaining ring.

The invention also encompasses a process of capping a bottle with the first embodiment of the new cap, characterized by the fact that it utilizes a capping head of a particular shape, the central part of which acts on the incurved end of said capsule so as to deform it while reducing the diameter of the internal sealing skirt to permit capping and cause straightening of the lip to a vertical position, said capping head then causing the assembly of said cap to descend until it abuts against the top of the neck of the bottle so as to provide a quasi-continuous internal seal from the retaining ring to the bottom of the straigtened lip along the length of the two internal and external walls of the neck.

Of course, when the second embodiment of the new cap is used, it suffices to exert sufficient force on the top of the cap to cause simultaneous penetration of the inner sealing skirt into the neck of the bottle and the retaining ring into the external groove in the bottle neck.

The characteristics of the new cap will be better understood from a reading of the following description of a preferred embodiment of the invention, which description is given purely by way of illustration and example, with reference to the accompanying drawings in which:

FIG. 1 is a diametral sectional view through a first embodiment of the new cap before it is placed in position on a bottle;

FIG. 2 is a bottom view of the cap of FIG. 1;

FIG. 3 is a diametral sectional view illustrating the cooperation between the capping head and cap before it is placed on the neck of the bottle;

FIG. 4 is a diametral sectional view of the assembly consisting of the neck of the bottle, the cap and the capping head after the cap has been placed on the neck of the bottle; and

FIG. 5 is a diametral sectional view of the second embodiment of the new cap taken in a plane passing through the middle of the hinge and the arcuate lifting projection.

FIG. 1 shows that the reinforcing ring 1 has a downwardly extending frusto-conical portion 1a which extends for a certain distance beneath the normal external retaining ring 2 having a constant radial thickness, so as to make it impossible to effectively lift the lower part 1b of the retaining ring on the side remote from the recess 3 provided to permit pivoting of the reinforcing ring 1 about a part 4 acting as a hinge, and by means of which the reinforcing ring is attached to the cap 5 proper.

In effect, as will be hereinafter seen, after capping, this lower part extends so close to an enlargement beneath the recess in the neck of the bottle that the insertion of a finger between this enlargement and the reinforcing ring to raise the latter becomes very difficult since the conical profile of the lower part of the ring also prevents any effective grip on the lower part of the ring 1.

The bottom plan view of FIG. 2 also shows the thin lower edge 1b of the ring 1.

As has already been said, the lower part 1a of the ring 1 beneath the retaining ring 2 is pierced by two notches 6 visible on FIGS. 1 and 2, which are located preferably adjacent the ends 4a and 4b of the hinge 4. The reinforcing ring 1, the larger part of which is visible in particular on FIG. 2, is connected in a conventional manner to the outer skirt 7 of the cap 5 by webs 8 which combine with the notches 6 to insure the inviolability of the cap.

The recess 3 is provided with ribs 3a which prevent the finger from sliding so as to permit it to lift the reinforcing ring 1 by exerting force near the retaining ring 2 at a point at which the enlarged portion of the ring 1 does not prevent such action, and causing it to pivot about the hinge 4.

The internal sealing skirt 9 has, as indicated above, and as will be seen in FIG. 3, an external diameter substantially larger than the internal diameter of the neck of the bottle with which the cap is to cooperate.

The incurved lower part of this sealing skirt is provided at its periphery, at the point of connection to the vertical skirt 9, with lip 11 which is conical in shape. The lower part 11a of this lip of which is visible on FIGS. 1 and 2.

The narrow inner part of the retaining ring 2 is shown at 2a on FIGS. 1 and 2, and the bottom of this retaining ring defines a corner 12 also shown on FIGS. 1 and 2. The ribbed recess 3 may also define at its upper end a horizontal ledge forming a sharp angle with the cylindrical wall of said recess carrying the grooves 3a and the diameter of the reinforcing ring 1 may be increased adjacent to this recess so as to constitute an arcuate ridge facilitating the pivoting of the reinforcing ring before its use as a removing ring.

A neck 11b is formed at the junction between the skirt 9 and the incurved bottom 10 so as to facilitate the straightening of the lip 11 to the vertical during removal of the cap.

Referring now to FIGS. 3 and 4 it will be seen that the capping head 13 matches the profile of the upper part of the cap 5 while always remaining above the upper part 1c of the reinforcing ring 1.

The head 13 is provided with a hollow central projection 13a pierced by a central hole 13b adapted to facilitate the operation of automatic capping machinery through connection to a vacuum pump so as to insure the adherence of the incurved part 10 of the cap to the capping head 13 before the cap is mounted on the neck 14 of the bottle.

It is easy to understand from FIG. 4 that the central projection 13a simultaneously deforms the bottom 10 to the position 10a as shown on FIG. 4 at the same time that the flat part 13c of the capping head is applied to the upper part of the cap 5. The diameter of 9 is thus so substantially reduced as to permit it to enter the neck 14. The lip 11 then assumes at 11c the vertical position shown on FIG. 4 in which this lip is applied against the inside of the neck 14.

In this manner a substantially continuous seal is provided from the retaining ring 2 to the lower edge of the lip 11 and especially at the level of the upper part of the cap 5. This seal is obtained because of the difference in diameter between the skirt 9 and the inside of the neck of the bottle and because of the necessity of deforming it to impart thereto an increased height by straightening the lip 11 to the vertical and applying it to the inside of said neck.

The action of the retaining ring 2 having a constant radial thickness and the reinforcing ring 1 prevents in practice any possibility of removing the cap by acting on the part 1b of the ring 1 on the side remote from the recess 3 since the shape of the enlargement 14a of a neck of the bottle makes it impossible to exert sufficiently great and long lasting force against the cap by inserting a finger between this enlargement and the part 1b of the reinforcing ring in view of the conical profile of the lower part 1a of the ring 1.

On the contrary, the lifting of the ring 1 and the rupture of the connecting webs 8 is very easily produced by placing the index finger in the ribbed recess 3.

FIG. 5 shows a reinforcing ring 1d the section of which is comparable to that of the ring shown on FIGS. 1, 3 and 4, except for the fact that the connecting hinge 4c connecting the ring and capsule proper 5a of an increased height, as is the cap 5a itself which extends to a level 12a lower than that of the retaining ring 2. The recess 3 and the ribs 3a visible in particular on FIG. 1 are replaced by a rib 3b having a variable thickness in the shape of an arc and projecting radially from the side opposite the hinge 4c. FIG. 5 does not show the notches 6 visible on FIGS. 1 and 2, but these could also be provided in this case.

Of course the reinforcing ring 1d is connecting to the outer part of the peripheral skirt 7a, having a slightly increased height as compared to the skirt 7 visible on FIGS. 1, 3 and 4, by connecting webs comparable to those shown at 8 on FIG. 2.

It will be noted that, in the two embodiments described, the upper part of the ring 1 or 1d is separated from the external skirt of 7 or 7a by a groove 7b in the vicinity of the connecting hinge 4 or 4c between these two members. The inner sealing skirt 9a of FIG. 5, which replaces the skirt 9 having an incurved bottom shown on FIGS. 1, 3 and 4, has no bottom comparable to the deformable bottom 10 shown on FIGS. 1, 3 and 4 and does not have the lip 11a and neck 11b shown on FIG. 1.

This skirt 9a has, on the contrary, at its lower part, a thinner portion 15 terminating in a frusto-conical part 16 connected to a cylindrical part 17 of increased thickness, the external diameter of which is sufficient to compensate for any probable variation in the internal diameter of the necks of the bottles with which this second embodiment of the cap is adapted to cooperate.

It is obvious that, in the case of the embodiment of FIG. 5, when sufficient pressure is exerted on the top 18 of this cap, this will cause the skirt part 17 having an increased thickness to penetrate into the neck of the bottle and the retaining ring into the external groove in said neck.

It will of course be appreciated that the embodiments which have just been described may be modified as to detail without thereby departing from the basic principles of the invention.

Claims

What is claimed is:

1. In a one-piece bottle cap made of plastic material having a depending external skirt, an internally projecting retaining ring on said external skirt, and a reinforcing ring encircling said retaining ring which may be used as a cap-removing ring and is attached to said cap by an integral hinge, the improvement according to which said reinforcing ring projects downwardly beyond the lower edge of the external skirt of said cap, and the external surface of the lower part of said reinforcing ring tapers inwardly toward a thin lower edge adapted to approach an enlarged section of the neck of a bottle carrying said cap, so as to inhibit the insertion of a finger between said edge of said reinforcing ring and said bottle neck.

2. Bottle cap as claimed in claim 1 which comprises an inner sealing skirt the upper part of which has an unstressed external diameter greater than the maximum diameter of the neck of the bottle to be closed by said cap.

3. Bottle cap as claimed in claim 2 in which said sealing skirt defines an upwardly open central cup having an incurved bottom, while the lower part of said sealing skirt has a frusto-conical external profile which decreases in diameter toward said bottom and terminates in a circular lip below said bottom, the lower part of said skirt being shaped to permit said circular lip and lower part to straighten to a vertical position when pressure is exerted on said bottom to increase its convexity and correspondingly reduce the diameter of the upper part of said sealing skirt until it can enter a bottle neck having a diameter smaller than the unstressed diameter of said upper part.

4. Bottle cap as claimed in claim 2 having a flat cover part which closes the top of said sealing skirt, which skirt has a cylindrical internal profile, the outer diameter of said sealing skirt being constant near its upper part while its lower part is frusto-conical and decreases in thickness toward its bottom, terminating in a thin part of constant radial thickness facilitating the penetration of said internal skirt into said neck.

5. Bottle cap as claimed in claim 1 in which the external skirt extends beyond the bottom of the retaining ring so as to increase the thickness of the hinge, the upper edge of which stops at a sufficient distance from the upper edge of the reinforcing ring to form between said external skirt and the upper part of said reinforcing ring a groove facilitating the swinging of the reinforcing ring to the position required for its use as a cap-remover.

6. Bottle cap as claimed in claim 1 in which the lower part of the reinforcing ring is provided with at least two notches positioned on opposite sides of the hinge.

7. Cap as claimed in claim 1 in which the reinforcing ring is provided on the side opposite said hinge with abutment means extending radially from the median part of the said ring to facilitate swinging of said reinforcing ring and the rupture of webs connecting said reinforcing ring to the external skirt on the side of said cap remote from the hinge.