US3780897A

US3780897A - Stoppers

Info

Publication number: US3780897A
Application number: US00113244A
Authority: US
Inventors: V Wassilieff
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-02-18
Filing date: 1971-02-08
Publication date: 1973-12-25
Anticipated expiration: 1990-12-25
Also published as: FR2085289B2; DE2107855A1; GB1349481A; FR2085289A2

Abstract

A container closure has a body, transverse closure means, a liquid-tight element having an annular face designed to place itself below and facing a non-cylindrical annular area of a container neck, and means capable of resilient deformation resting on the end face of the neck, so as to exert an axial traction on the body and to maintain the said annular face and area in mutual contact. The closure may be formed from a one piece blank.

Description

United States Patent [191 Wassilieff STOPPERS [76] Inventor: Victor Wassilieff, 84, rue de lAssomption, Paris, France [22] Filed: Feb. 8, 1971 Appl. No.: 113,244

[30] Foreign Application Priority Data Feb. 18, 1970 France 7005737 Apr. 7, 1970 France 7012464 [52] US. Cl 215/41, 215/42, 215/46 A, 215/47, 215/DIG. 1

[51] Int. Cl 865d 41/22, B65d 41/20 [58] Field of Search 215/40, 41, 42, 46 A, 215/47, 55, DIG. 1; 220/42 L, 60 R [56] References Cited UNITED STATES PATENTS 3/1971 Livingstone 215/41 6/1962 Wieckmann... 215/DIG. 1 12/1964 Healy 215/41 8/1965 Plunkett 215/40 Dec. 25, 1973 3,042,242 7/1962 Abt 215/46 A FOREIGN PATENTS OR APPLICATIONS 1,463,103 11/1966 France 215/47 1,432,123 3/1969 Germany 54,898 3/1967 East Germany 801,540 12/1968 Gfiadfilll 215/47 554,079 1/1957 Italy Primary Examiner-William T. Dixson, Jr. Assistant Examiner-Stephen Marcus Attorney-Young & Thompson [5 7] ABSTRACT The closure may be formed from a one piece blank.

12 Claims, 23 Drawing Figures STOPPERS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to closures for containers of the type having a neck with an annular rim on the inside face of the neck. The invention also relates to one piece moulded blanks from which the closures are formed.

2. Description of the Prior Art There are at present in existence two main types of closures for containers of this kind. The closures of the first type have two elements, which are:- a thin-walled cap in resilient material, and a wrenchable metal cover, which guarantees non-interference and maintains the pressure between the bottom of the cap and the end face of the neck. As regards the closures of the second type, they consist in a single element having inner and outer cylindrical skirts, the outer skirt holding the closure in position by engagement and retaining the bottom against the edge of the neck. Non-interference is ensured by the need to pull off or to destroy partially the outer skirt. In this second type the inner skirt must be reinforced, which is generally done by forming it by moulding in two thicknesses, so as to increase the solidity of the closure and its liquid-tightness, as the liquid contained in the bottle may accidentally cause, through its own weight, the opening of the container.

These two types of closure are designed with a view to effecting liquid-tightness by contact with the inner cylindrical face and the end face of the neck. In practice, this tightness is not entirely satisfactory for, if the closure is too tight in the neck, it tends to spring off spontaneously, at least after replacement following removal of the closure. Furthermore, these known closures are costly, for they demand either as appreciable weight of moulding material, or the use of two elements. In addition, there are sometimes difficulties with the removal of the closure.

The present invention has for its object a closure for containers of the above-mentioned type, formed of a single element, more economical than the known closures and more liquid-tight, both before and after the first removal of the closure, easy to re-use, and easily adaptable to a fool-proof device.

SUMMARY According to one aspect of the invention a closure comprises a body, an annular face projecting radially on the circumference of the body and adapted to be placed below and facing an annular area formed on the inside face of a container neck by pushing the stopper down the neck, as well as a means able to perform a traction on the said body by resting on the neck, and to keep the said annular closure face against the said annular area of the neck.

A closure thus formed is liquid-tight, as the product tending to escape has the effect of compressing the annular face against the neck. It is economical, for the body, called upon to work in axial traction, and not needing to be tightly clamped by the neck, has not to be rigid. It is easy to remove and to replace, as a result of the free play it is possible to provide between the body and the neck. It is easily adaptable to include interference-proof devices,'as will be described below.

The characteristic means affording such advantages are not limited only to containers provided with a noncylindrical annular area on the inside face of the neck, but are also adaptable to the containers the neck of which has such an annular ring on its outer face.

Therefore, according to another aspect of the invention a container closure has a skirt and transverse closure means, characterised in a liquid-tightness annular area formed radially projecting from the inside face and adapted to be placed below and facing a noncylindrical annular area of the outer face of the container neck by a capping movement of the stopper on the neck, as well as by means able to effect an axial traction on the skirt, resting on the end face of the neck, and of holding the said area and annular area in mutual, surface or linear contact.

Such a closure is distinguished from existing capping closures by its method of liquid-tightness, which is the result of a contact performed in an axial, and no longer radial, direction, and held tensioned between the neck and the closure. The pressure at the sealing joint therefore increases with the pressure of the container contents which makes it possible, in fact, to achieve selftightness. Accordingly, axial tension on fitting may be reduced, and savings in raw material may thus be made. This saving of raw material is all the more appreciable as, for a given force of compression exerted on an annular sealing joint in a specific closure, the stresses created in the closure are appreciably weaker when this force is the outcome of an axial tension than in the case where it originates from radial expansion.

As regards the axial traction exerted on the skirt, this is necessarily accompanied by the deformation of one or more elements of the cork. The invention thus provides for arrangements intended to facilitate such a deformation and to ensure the permanence of this axial traction. It is known, indeed, that unlike certain materials said to be perfectly resilient, plastics materials exhibit elasticity only for a part of the total deformation imparted to them, the remaining portion constituting a residual deformation, which subsists after removal of the stresses. The residual deformation increases at a lower rate than the total deformation, and it is therefore desirable to increase total deformation to increase the relative importance of the purely elastic deformation, this being the only one to ensure the presence of a permanent axial traction on the skirt of the closure. In addition, stresses being equal, the deformations by bending are more pronounced than the deformations by traction or pure compression, and the invention provides arrangements making it possible to deform by bending one or more elements of the closure, which facilitates the positioning of the closure while ensuring the achievement of the desired axial traction, in spite of the tolerated size variations which may be exhibited in practice by container necks and stoppers.

In one form of the invention, the closure is made resiliently deformable in an axial direction by giving the transverse closure means a non-flat shape, for example a cupshaped section.

The closure may be made resiliently deformable in the axial direction, between the two supports constituted by the neck end face and the sealing annular area, by providing on the inner face of the transverse closure means one or more projections adapted to come in contact with the end face of the neck and, preferably, to curve resiliently in the radial direction, when the stopper is fitted on the container.

The invention also provides a blank moulded in one piece, intended to make a closure as described above, the blank comprising transverse closure means, a skirt connected to said transverse closure means, and an underskirt formed sprung back in relation to the skirt, the skirt and the under-skirt being joined together by a thin cord of moulding material along their respective lower and upper edges, the under-skirt being designed to turn over radially inwards by folding down around the said cord, and to apply itself against the inner face of the skirt, and the said liquid-tight annular face of the, closure being formed on the free edge of the under-skirt.

The invention further provides a closure made from a blank as described above, in which the skirt is composed of two layers, the said annular area being formed on the upper edge of theinner layer, the lower edge of the latter being connected to, or engaged in, the outer layer.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 represents in axial section, by way of example, a stopper type closure according to the invention placed above a container neck;

FIG. 2 represents these same elements assembled together;

FIGS. 3, 4, 5 and 6 represent in axial cross-section alternatives of the stopper of FIGS. 1 and 2;

FIGS. 7 and 8 represent in elevation and crosssection respectively a stopper according to the invention provided with an interference-proof device;

FIGS. 9 and 10 represent another interference-proof device shown in axial cross-section and plan view respectively;

FIG. 1 1 represents in axial cross-section a third interference-proof device associated with a stopper according to the invention;

FIG. 12 represents in axial cross-section a container neck having a cap type closure or stopper according to the invention, before the final placing of the stopper;

FIG. 13 represents the stopper of FIG. 12 in final closing position; 1

FIG. 14 represents another type of stopper according to the invention in partial axial cross-section;

FIG. 15 represents the stopper of FIG. 14, fitted on a container neck in closing position;

FIGS. 16 and 17, corresponding to FIGS. 14 and 15, relate to an alternative;

FIG. 18 and FIG. 19 represent two other alternatives;

FIG. 20 represents a method of manufacture of a stopper according to the invention, by moulding in plastics;

FIG. 21 represents an alternative of FIG. 20;

FIG. 22 represents a fragmentary view, in initial closure position (that is to say before the first removal of the stopper) of a stopper made with the blank of FIGS. 20 or 21; and I FIG. 23 represents the stopper of FIG. 22, after resealing of the container.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In each embodiment the various elements will be described and qualified in the positions they occupy on the drawings, that is to say with containers and stoppers with vertical axis, the containers being opened upwards and the stoppers oriented in closing position.

Referring to FIG. 1, a container neck, of known type, and frequently made in relatively rigid plastic material, has a flat end face 2 and has on its outer surface, under face 2 a re-entrant annular ring 1 the effect of which is to form on the inner face of the neck an annular zone in the shape of a truncated cone 3 flaring out downwards and oriented towards the bottom of the container, an annular zone in the shape of a truncated cone 4 flaring out upwards and oriented towards the opening, and a cylindrical area 5 connecting areas 3 and 4 by 1 their respective small diameter edges, i.e., their upper and lower edges respectively. A stopper 6 is composed of a body 7 made of a cylindrical skirt closed by a bottom 8 along its lower edge, of a collar 9 in the shape of a truncated cone, starting at the line of junction of the skirt and of the bottom, and flaring out downwards from that line, and of an upper second collar. The latter is composed of a part in the shape of a truncated cone or of dished shape 10 which flares out downwards from the upper edge of the skirt with which it is integral, and of a cylindrical edge 11 directed downwards from the bottom edge of part 10.

FIG. 2 represents the stopper 6 fitted in the neck in closing position. The stopper introduced itself in the neck by resilient deformation of the collar. The collar 9 slides, while undergoing deformation, along the inclined area 4 of the neck, goes beyond area 5, and comes to lodge itself by snapping out below area 3, the stopper being thus held in the neck. The part 10 in the shape of a truncated cone of the upper collar has become deformed upwards as it flattened against the flat face 2 of the neck, which is surrounded by the cylindrical edge 11 of this collar. The permanent upward deformation thus imparted to the portion of collar 10 has for its effect the exertion of an axial traction on skirt 7, and to hold the upper face of the lower collar 9 applied against the inner face 3 of the neck. Moreover, the liquid-tightness thus obtained can only be improved under the pressure likely to be exerted by the contents of the container, and it is not dependent upon a clamping effect on skirt 7, which makes it possible to allow play between the skirt 7 and face 5 on the neck, and thus to facilitate the operations of removal and re-insertion of the stopper. The stopper thus formed requires only a small weight of moulding plastics material, as the deformations needed require no compression effect and are made, more precisely, by flexion of the collars with the placing of the skirt under axial traction.

The method of embodiment of FIG. 3 differs from the foregoing in the elimination of the lower collar and in its replacement by a ridge l4 projecting on the outer face of skirt-7, at its lower portion. This ridge has an upper face 12 in the shape of a truncated cone 12 flaring out downwards and slanting slightly from the horizontal, and a lower face 13 in the shape of a truncated cone, converging downwardly and slanting slightly from the vertical. The lower face 13, therefore, facilitates the penetration of the stopper in the neck of the container, and the positioning by snapping out of the face 12 against face 3 of the neck.

In FIG. 4, the skirt 7 has neither a collar 9 nor a ridge 14 but is extends downwards, beyond bottom 8, by means of a crinoline 15 having two

outer faces

12, 13 which play the same part as those of FIG. 3. The inside face of crinoline 15 is connected by gusset straighteners 16 to the lower face of bottom 8.

In the embodiment of FIG. 5, the skirt 7 is provided with an upper bottom 17 which has the appearance of a dome'shaped protruding roof. The protruding part acts as the upper collar of the foregoing examples. The skirt 7 is provided at its lower portion with a ridge 14 similar to that of FIG. 3, with, in addition, an annular groove 18 hollowed out on its outer face, immediately above face 12 of the ridge, the clearance thus created above this face having the effect of facilitating its application against face 3 of the neck, while making it possible, as an additional precaution, to provide tight contact between the outer face of the skirt and face 5 of the neck.

In the alternative embodiment of FIG. 6, the skirt 7 has an upper bottom 17'similar to that of FIG. 5, but provided with a downwardly directed cylindrical edge 11. The skirt bears on its outer surface a ridge 14, similar to those previously described, and has above the latter an annular throat 19 of trapezoidal outline in crosssection, adapted to receive the outline of the same shape constituted by the neck faces 3, 4 and 5.

The material in which the closure device according to the invention is made, and the dimensions adopted give it the characteristics of flexibility and deformability required to make it possible to extract the stopper without destroying it, with a view to its reuse, by the sliding of its

part

9, 14 or along the neck face 3, and its radial compression as it passes along the neck face 5. An experienced technician will easily be able to choose as a function of such requirements a suitable manufacturing material from among those currently available, and size the stopper as a function of the dimensions of the neck.

The removal of the stopper is particularly easy when, according to the example chosen, the sliding face 3 is a smooth face made of plastic material, and has the shape of a downwardly flaring truncated cone.

Moreover, the flexibility of the sealing element, required to make the removal of thestopper easy, promotes the compression of this element against the face 3 of the neck, under the pressure of a gas or liquid content, in a bottle laid flat or upside down.

Referring to FIGS. 7 and 8, a stopper according to the invention is provided with an edge 11 which extends downwards to cover the throat I of the container neck. The edge 11 has on its inner face, at two diametrically opposed points, two projections 20 inserted into the throat I, and it is provided, on its outer face, with two tabs 21, aligned on the inner projections 20 and directed downwards. Two tear-off lines 22, formed in the edge 11 starting from its lower edge and located on either side of each of the tabs 21, extend upwards as far as a horizontal reinforcement 23, formed so as to project from the outer face of edge 11. To remove the stopper from the container, it is necessary to cause the projections 20 to come out of the throat 1, by swivelling the tabs outwards around the reinforcements 23, which gives rise to the tearing off of the edge along lines 22.

In FIGS. 9 and 10, the bottom 8 integral with the skirt 7 of the stopper has, hanging down, on its lower face, a crinoline 15 composed of, in succession from top to bottom, a cylindrical portion 24, located recessed in relation to skirt 7, a portion in the shape of a truncated cone flaring out downwards and slanting slightly from the horizontal, and finally a portion in the shape of a truncated cone 26 converging downwards and slanting slightly from the vertical. The outer faces of

parts

25, 26 play respectively the parts of

faces

12, 13 described above, and the recessed position of part 24 in relation to skirt 7 forms a clearance which facilitates contact between part 25 and face 3 of the neck. The skirt 7 is provided with an upper collar formed of a part 10 applied on the end face 2 of the neck, and of a cylindrical edge 11, provided with a tab 27 radially directed outward. A slit 28 in the shape of an arc of a circle is made between

parts

10 and 11 perpendicularly to tab 27, and these two

parts

10, 11, are joined, on the remainder of their circular connection line, by a tearable joint 29. To remove the stopper from the container, the stopper is pulled by part 11, the only one accessible. The effect of this is to separate it from part 10, which, becoming in its turn accessible, may be gripped to extract the stopper.

FIG. 11 represents a stopper whose skirt 7 has a cylindrical lower portion 30 situated retracted in relation to the remainder of the skirt. The latter is provided with an upper collar composed of a part 10, applied on the end face 2 of the neck, a cylindrical part 11 surrounding the neck, and a flat part 31 forming an annular edge radially directed outwards, on the circumference of part 11. A ring 32, having outside an upper face 33, placed in contact with neck face 3, and a lower face 34 in the shape of a truncated cone converging downwards and slightly inclined on the vertical, is connected to the lower edge of the skirt by a tear-off joint. The traction effort exerted on the edge 31 to remove the stopper gives rise to the separation of ring 32, which thus constitutes an element of guarantee, i.e., proof against interference, as long as it remains connected to the remainder of the closure.

In the embodiment of FIG. 12, a neck 101 of a glass container has a flat end face 102 which is connected by a rounded portion 103 to a lateral face which has, in turn from top to bottom, an annular ring or throat 104, an annular ridge 105, and a cylindrical face 106..

A stopper 107 has a principal body composed of a skirt 108 and a closing bottom 109, connected together by a rounded-off portion.vThe stopper 107 is provided with a sealing guarantee ring of known type 110, connected to the skirt by a breakable joint. The skirt 108 has on its inner face an annular projection with a sawtooth outline, the sharp edge of which is denoted by the reference numeral 111. As regards the cover 108, this has a cup-shaped outline. The guarantee ring 110 ends at its bottom edge in an annular projection 112 with saw-tooth outline, directed radially inwards.

As shown in FIG. 12, the stopper 107 rests freely on the neck 101 before being permanently fixed thereto, the closing bottom being located at a distance from the end face 102 of the neck, and the guarantee ring 110 resting by its lower edge 112 on the side of the neck which connects the throat 104 to the ridge 105.

FIG. 13 represents the whole of the stopper 107 fixed in closing position on the neck by a downwardly directed axial movement. During this movement, the closing bottom 109 comes in contact with the end face of the neck, then straightens up resiliently by adopting an appreciably flat shape, whereas the bottom portion of the skirt 108 expands radially sliding on the rounded-off portion 103, then returns on a snapping movement to its initial diameter, the annular edge 111 then coming in contact with the face of throat 104'. This contact is maintained under axial tension by virtue of the tendency which the closing bottom 109 has to reassume its initial cup-shape. At the same time, the lower edge 112 of the guarantee ring 110 expands radially sliding downwards on the ridge 105, then returns by snapping, and is immobilised, under this ridge.

' As will be clear from FIG. 13 any pressure exerted on the inner face of the closing bottom 109, resulting from the pressure of the container or from the carrying of the container in inclined position or upside down, will have the effect of increasing the contact pressure between the sharp edge 111 and the face of throat 104, which ensures liquid-tightness automatically. Moreover, in this embodiment, skirt 108 need not have any permanent radial deformation, and is not called upon to exert any radial pressure on the neck, its essential role being to act as a connecting tie between the bottom 109 and the element-111. There results an appreciable saving of raw material. It should be pointed out, moreover, that the linear or sharp edge contact between the stopper and the neck at the sealing joint increases the efficiency of this joint.

It is not necessary to give to the stopper, at the level of edge 1 11, a diameter appreciably lower than that of the container neck, as liquid-tightness is not dependent upon the annular pressures of the stopper at that level.

Referring to FIG. 14, the closing bottom 109 of the stopper 107 has an integrally moulded fiat shape, and has on its lower face an annular rib 113, the outer face 114 is straight throughout its length, while its inside face 1 ends with a bottom roundedoff portion. Moreover, the stopper of FIG. 14 is similar to that of FIGS. 12 and 13 as regards its other constructional details and its method of fixing to a container neck. FIG. 15 represents the stopper in closing position, that is to say fixed to the neck 101. In this position the rib 113, having come in contact with the end face 102 of the neck, became crushed against this face and bent radially outwards, the clamping of the stopper on the neck keeping the stopper resiliently compressed and bent in the manner of a spring. There results a permanent axial traction on the skirt 108 and a permanent compression at the sealing joint that is formed by edge 111 with the face of the throat 104. Moreover, the rib 113 constitutes an additional sealing joint on the end face of the neck.

The fragmentary FIGS. 16 'and 17, corresponding to FIGS. 14 and 15, represent an alternative thereof which consists in providing a bottom rounded-off portion on the outer face 114 of the rib 113, and not on its inner face 115, in such arnanner as to enable it to bend radially inwards by compression against the end face 102 of the neck 101 (FIG. 17).

The fragmentary view of FIG. 18 represents an alternative of the device in FIG. 16, and according to which the rib 113 has an end in the form of a bevel, adapted to come in linear contact with the end face 102 of the neck, and to bend radially inwards to assume the position shown in dotted lines. In the same way as the embodiment of FIG. 16, that of FIG. 18 has, in relation to the device of FIG. 14, the advantage of exposing the inner face 115 of the rib to the pressure of the contents of the container, the effect of which is to increase the contact pressure between the opposite outer face 114 and the neck, and thus to achieve an additional joint which ensures self-sealing, starting from the end face 102 of the neck.

FIG. 19, relating to an alternative of the embodiment of FIG. 18, represents a stopper according to the invention the closing bottom 109 which is provided, on its inner face, with three concentric annular ribs 113, with bevel-shaped ends, which constitute three lines of defence against leaks.

FIG. 20 represents a blank 107A, moulded in one piece, intended to make in its final form a stopper according to the invention. The blank 107A has a closing bottom 109, a skirt 108 A directly connected to the bottom 109, and a skirt 108 B formed sprung back in relation to the skirt 108A, the

skirts

108A and 108B being joined together by their respective lower and upper edges. The upper edge 116 of the sub-skirt 108B is tapered, so that the two skirts are connected together only by a thin cord of moulding material, along the circumferential line 117. To form the stopper from that blank, the under-skirt 108 B is turned in the direction of the arrows F, by causing it to pivot towards the inside in relation to line 117, in such a way as to apply it against the inside face of skirt 108A and to give it the position shown on FIG. 22. The

unit

108A, 108B thus made, is equivalent to the skirts 8 of the foregoing embodiments, the free edge 118 of the underskirt 108B performing the role of the above-mentioned annular projection 11. I

In FIG. 20, the closing bottom 109 is provided on its bottom face with a saw-tooth profile annular rib 113, through which it comes in contact with the end face 102 of the neck only along a line or an annular area of reduced thickness.

Skirt 108A has at its base an annular gripping flange 1 19 on its outer face, and a recessed portion or corner of angular shape on its inner face.

FIG. 22 shows the stopper formed with the blank of FIG. 9, fixed in closing position on a container neck 101. The annular rib l 13 is in contact with the end face 102 of the neck, and the free edge 118 of the underskirt 1083 is in contact with face 104 of the neck throat, this contact being maintained under tension by deformation of the sealing bottom 109 and by the axial traction created in the skirt 108A. To effect the first removal of the stopper from the container thus closed, the unit 108A to 109 is gripped by the flange 1 19, and it is separated from element 108B along the cord 117, the latter thus forming a guarantee bond. To re-stopper the container, the stopper is put back into place on the neck (FIG. 23) and the skirt 108A is pulled downwards until the engagement is effected in its recess 120 of the lower bevelled end 116 of the under-skirt 1088 which has remained fixed to the neck at the time of the first unstoppering. The sealing effect achieved by contact under tension between the edge 118 of the under-skirt 108B and the face 104 of the neck is thus preserved both before and after the breaking of the breakable joint.

In the alternative of FIG. 21 there is allowed to remain between the skirt 108A and the under-skirt 1088 a thick non-breakable part 121, occupying a small angular sector and adapted to create between the skirt and the under-skirt a permanent connection effecting a swivelling joint, and enabling the opening part 108A to 109 of the stopper to be connected to the neck of the container after unstoppering.

I claim:

1. A container closure for a container provided with a neck having an end face and an internal side face with a re-entrant annular area, said closure being formed as a one-piece molding of resilient material comprising an axially extending body for insertion into the neck, transverse closure wall means, means integral with the body and capable of resiliently flexing in an axial direction by bearing upon said end face, a portion integral with the body and having an annular sealing face axially spaced below said resilient means, the flexion range of the latter being such that insertion of said portion and body into the neck and engagement of the resilient means with the end face of the container, followed by a downward axial thrust applied to the closure, is operative in flexing upwardly relatively to the body said resilient means bearing upon said end face to the extent required for enabling the annular sealing face to move down and take a position below and facing said reentrant annular area, subsequent release of said thrust tending to raise the annular sealing face and causing it to sealingly engage the annular area, with said resilient means remaining flexed and said body maintained under axial traction. I

2. The closure of claim 1, wherein the body is radially dimensioned to be substantially free from contact with the internal side face of the container neck.

3. A closure according to claim 1, in which the sealing face is the upper face of a collar in the shape of a truncated cone flaring out downwards and connected to the body along its small base.

4. A closure according to claim 1, in which the body has on its outer face a part in the shape of a truncated cone flaring out downwards and comprising the abovementioned sealing face, and also a part in the shape of a truncated cone converging downwards and located below the sealing face to facilitate the insertion of the closure.

5. A closure according to claim 4, in which the outer face of the body has an annular throat situated immediately above the sealing face.

6. A closure according to claim 5, in which the throat has an outline designed to receive an element of corresponding outline, comprising a ridge formed on the internal side face of the container neck.

7. A closure according to claim 1, in which the body is of hollow shape, and has a skirt, extending over at least part of its height.

8. A closure according to claim 1, further having an outer skirt designed to surround the container neck and provided on its inside face with at least one projection designed to enter a recess formed on the outer face of said neck, the said skirt, provided on its outer face with a tab located perpendicularly to the projection, being provided with two tear-off lines on either side of the tab.

9. A closure according to claim 1, including a grip-' ping edge hidden by a wrenchable tear-off ring.

10. A closure according to claim 1, in which the body comprises two upper and lower portions joined together by a circular tear joint, the lower portion providing the sealing face of the closure.

11. A closure according to claim 1, in which the sealing face of the closure is formed of a compressible material, and is able to conform to the shape of the annular area of the container neck, under the action of an internal pressure exerted by the contents of the container.

12. A closure according to claim I, mounted on a container having said neck, the annular area of the neck having a shape flaring out downwards.

Claims

1. A container closure for a container provided with a neck having an end face and an internal side face with a re-entrant annular area, said closure being formed as a one-piece molding of resilient material comprising an axially extending body for insertion into the neck, transverse closure wall means, means integral with the body and capable of resiliently flexing in an axial direction by bearing upon said end face, a portion integral with the body and having an annular sealing face axially spaced below said resilient means, the flexion range of the latter being such that insertion of said portion and body into the neck and engagement of the resilient means with the end face of the container, followed by a downward axial thrust applied to the closure, is operative in flexing upwardly relatively to the body said resilient means bearing upon said end face to the extent required for enabling the annular sealing face to move down and take a position below and facing said re-entrant annular area, subsequent release of said thrust tending to raise the annular sealing face and causing it to sealingly engage the annular area, with said resilient means remaining flexed and said body maintained under axial traction.

4. A closure according to claim 1, in which the body has on its outer face a part in the shape of a truncated cone flaring out downwards and comprising the above-mentioned sealing face, and also a part in the shape of a truncated cone converging downwards and located below the sealing face to facilitate the insertion of the closure.

9. A closure according to claim 1, including a gripping edge hidden by a wrenchable tear-off ring.

12. A closure according to claim 1, mounted on a container having said neck, the annular area of the necK having a shape flaring out downwards.