EP1335864A1

EP1335864A1 - Child-resistant safety closure

Info

Publication number: EP1335864A1
Application number: EP01976362A
Authority: EP
Inventors: Didier Lancesseur; Roger Nobilet
Original assignee: Airsec SAS
Current assignee: Airsec SAS
Priority date: 2000-10-04
Filing date: 2001-10-04
Publication date: 2003-08-20
Anticipated expiration: 2021-10-04
Also published as: FR2814724B1; CA2424324C; CA2424324A1; JP2004526631A; FR2814724A1; DE60111416D1; EP1335864B1; DE60111416T2; AU2001295660A1; US20040045923A1; ES2243562T3; CN1478040A; WO2002028737A1; CN1258468C; ATE297350T1

Abstract

Safety screw-closure device for a container provided with an outer screw thread opening, which is made up of two coaxial caps, nested one inside the other, one of them, an outer cap, being able to turn the other, an inner one, by axial pressure and turning: the outer cap comprising, on the inner surface of one of its walls, mutual-engagement means; the inner cap comprising a screw thread on the inner surface of its cylindrical side wall and mutual-engagement means on the outer surface of its wall, facing the wall of the inner cap comprising the mutual-engagement means; and an elastic means disengaging the mutual-engagement means of the walls of the two inner and outer caps, placed between the upper end walls of the two caps, and made of a material of different composition from the composition of the caps.

Description

SECURITY CLOSURE FOR CHILD PROOF

Field of the invention

The invention relates to a safety closure device by screwing a container, the mouth of which is provided with an external screw thread, device resistant to a young child.

The invention relates more particularly to a screw-on safety closure device for a container, such as a bottle, comprising an internal plug to be screwed onto said container and an external coaxial plug completely covering the internal plug, the external plug having the capacity to drive the internal plug via a latching system when axial pressure and rotation are applied to the external plug.

State of the art

Safety devices resistant to young children, for the closure by screwing of containers with a screw thread mouthpiece, have appeared for many years.

These devices consist of two plugs / caps fitted one inside the other, each formed by a cylindrical side wall and an upper end wall closing the cylindrical wall.

The internal stopper comprises a thread of screws on the internal surface of its cylindrical wall allowing it to close off by screwing the container, and means on its walls external cylindrical and / or end allowing it to be driven in rotation by the external cap. The external cap coaxial with the internal cap which completely covers the internal cap, comprises, on its internal walls, means for driving, in rotation, the internal cap in the direction of closing or opening of the container, by axial pressure / rotation applied to the external plug, this pressure making it possible to mechanically engage the drive means of the external plug in the corresponding means of the internal plug, then to transmit the rotational movement of said internal plug.

One or the other of the two plugs also comprises elastic means allowing the mechanical disengagement of the drive means of the external and internal plugs, these elastic means being made of the same material as the plugs by injection-molding.

Such safety closing devices resistant to young children have been described in numerous patents, some of which are mentioned below by way of illustration.

A first device which has been the subject of European patent EP 0631943 relates to the safety closure (childproof) of a container comprising a screw thread, which consists of two fitted caps, one internal for closing said container, the other external for driving the internal plug for opening or closing the container, by a combined action of pressure and / or rotation.

In this device:

- the internal screw cap has, on the external surface of its cylindrical wall, a groove made up of successive ribs, in the form of strips, which extends on the external surface of its upper end wall, in the form of a radial groove the lamellae of which have a long side, oriented in the direction of rotation for opening, and a short side preferably situated in the plane containing the median longitudinal axis of the container closure;

- The external plug has, on the internal surface of its upper end wall which is deliberately convex (closing the cylindrical wall), projections, which engage in the grooving of the internal plug when an elastic deformation of the wall upper end of said outer plug is made by axial pressure on said wall.

Consequently, by axial pressure applied to the internal face of the convex end wall of the external plug, then rotation imparted to said plug, a torque is transmitted to the radial grooving of the internal plug, by the projections of the external plug, such so that the inner cap is unscrewed from the container.

The device also comprises, as already said, the grooving in lamellae oriented on the. cylindrical external wall of the internal plug, the function of which is to facilitate the rotation of the internal plug to be screwed into the external plug, when the projections of the external plug are not engaged in the oblique lamellas of the radial grooving of the internal plug.

The device also comprises a second system for driving the internal plug in rotation by the external plug in the screwing direction, independent of the first drive system, so that the external plug drives the internal plug in the closing operation. , by a simple rotation, without there being any need to apply an axial pressure on the convex external wall of the end of the external plug: this drive system is constituted by means placed on the internal cylindrical wall of the external plug, as designated by "front surfaces" and means placed on the external cylindrical wall of the internal plug, as designated as projections.

This closing device, known as a safety device, for children has drawbacks which can be revealed during its operation.

For example, the outer plug (like the inner plug) is made of a single polymer material having a more or less elastic property and the projections of the inner face of the upper end wall of the outer plug are made of the same material and are obtained by injection-molding in superstructure of said internal face of said plug: as the upper end wall of the external plug is convex and stressed many times by the practice of the axial pressure-rotation couple for the opening of the container, the memory elastic of the constituent material weakens and the deformation of this upper end wall can become quasi-permanent due to the effect of fatigue of the material, so that the projections can be engaged in a relatively permanent manner and that the internal plug can be rotated in either of the screwing or unscrewing directions.

Thus, when the fatigue effect of the material occurs, the upper end wall of the external plug no longer deviates sufficiently from the external surface of the end wall of the internal plug: the device is no longer d 'absolute safety, because the snap-fastening of the two plugs can occur independently of the necessary axial pressure-rotation.

Another device which has been the subject of European patent EP0602925 relates to the closure, inviolable by a child, a container comprising a screw thread which also consists of two plugs fitted one inside the other, one internal intended for closing said container, the other external intended to drive the first for opening or closing the container by the action of an axial pressure and / or a rotation.

In this device:

- The external plug has, on the internal face of its upper end wall, oblong snap-in bars oriented radially and an elastic means in its central part, to keep apart the upper end wall of the external plug from the wall upper end of the inner plug;

- The internal screw cap has, on the internal surface of its cylindrical wall, a screw thread and on its upper end wall oblong and radially oriented latch bars. These bars have inclined faces (in the direction of screwing of the internal plug) and abut on the latching bars of the external plug, when said external plug is subjected to rotation in the screwing direction by driving the internal plug. However, when said plug is subjected to rotation in the unscrewing direction, without the prior application of an axial force on the upper end wall of the external plug, the bars of the internal face of the upper end wall of the external plug slide on the inclined faces and the internal plug is not driven.

Thus, it follows that the unscrewing of the internal plug is obtained by the successive application of an axial pressure on its upper end wall, which brings said wall closer to the upper end wall of the internal plug and causes 1 ' snap-fastening the bars of the upper end wall of the external plug into the bars of the end wall upper inner plug, the inner plug then being rotated by the outer plug.

As soon as the pressure applied to the upper end wall of the external plug is released, the snap-on bars of the external plug disengage from the snap-on bars of the internal plug, thanks to the elastic system which causes the uncoupling of the two plugs.

However, this closing device, known as a safety device, for children comprising two plugs, also has drawbacks which are revealed only in use.

Regarding, for example, the external plug, its means constituted by the latching bars of the external plug and its elastic means present on the internal surface of the upper end wall of said plug, are produced (by mold injection) by means of a single polymer material having a certain natural elasticity. More specifically, the elastic means is formed by four vertical tongues secured by one of their ends to the internal surface of the upper end wall of said plug. These four tabs form a virtual cylindrical wall, coaxial with the external plug. When applying pressure to the upper end wall of the outer plug, these four tabs tend to move apart from each other, in their lower end, then crash into the upper end wall of the internal plug, throughout the application of the above pressure.

By releasing said pressure, the tabs must return to a vertical position. But in practice, the repetition of the axial forces (axial pressure-rotation), on the external plug for unscrewing the device, causes fatigue of the constituent polymer materials which is manifested by a almost permanent deformation of the elastic means and possibly its rupture in whole or in part.

Thus, the upper end faces of the two plugs are no longer sufficiently spaced from one another at rest and their close relative position tends to cause one accidental snap of the drive teeth of the outer plug with the teeth of internal plug drive. The closing device, called security, for children is therefore no longer absolutely secure.

Another device which is the subject of European patent EP 0725012, proposes a closure considered as inviolable by a child of a container comprising a screw thread which is composed:

S ^• an inner cap having a cylindrical side wall and an end wall, to be driven,

^• an external cylindrical envelope for driving open so that the upper opening of this cylindrical envelope has a diameter slightly greater than the diameter of the barrel of the internal plug, which allows the internal plug to emerge above said envelope cylindrical external. '

Once inserted into the external cylindrical envelope, the internal plug retains said cylindrical envelope, in the lower part by a crown on which it abuts, and in the upper part by an external crown on which abuts its upper perimeter surface.

The external cylindrical drive envelope has on its internal surface latching means which can also be means for guiding the internal plug. As for the internal plug, its only latching means allowing it to be driven by the cylindrical envelope is present on the external lateral wall of said plug. The mechanical driving of the internal plug by the external cylindrical casing is therefore carried out by means of the latching means of the cylindrical casing and the snap-on means of said internal plug when a mechanical pressure torque is applied to the 'envelope to bring it down and snap, and rotation of the envelope to drive the internal plug.

The elastic uncoupling means is formed by blades of the lower crown of the internal plug, these blades being of the same composition and integral with said lower crown by one of their ends and finding accommodation in said crown when pressure is exerted from above. below on the outer cylindrical casing.

Thus, it appears that the means used in this device make it difficult to drive the internal plug because they require the application of a vertical force on the external cylindrical envelope, first requiring the complete perimeter grip of said envelope. according to an awkward movement, and then the application of the vertical force on the perimeter of the envelope to cause the locking of said envelope and of the plug and finally the driving of the internal plug by rotation of the external cylindrical envelope.

It also appears that the elastic uncoupling means is placed on the lower crown of the internal plug and is made with the same material (composition) constituting the plug and the external cylindrical envelope, material which, when frequently used, can lose part of its elastic capacity, and can reach a state of fatigue such that it can crack and lose its elasticity, or even break.

Finally, another device which was the subject of GB patent 2,209,156, describes a safety closing device for the fire hydrants for water supply. This device includes an internal plug in technical polyamide and an external plug in aluminum alloy.

The internal plug has a screw thread on its internal wall which engages on the screw thread of the nose of the water outlet.

The external plug is held in a coaxial position with the internal plug by means of a perimeter ring which constitutes the guide means, holding the two plugs coaxially constituting the elastic means for uncoupling the two plugs.

S A spring is located between their opposite upper faces, supported in appropriate coaxial circular grooves.

The pressure-rotation drive means of the internal plug by the external plug consists of:

X three teeth placed on the internal surface of the upper end of the external plug which engage, when pressure-rotation is carried out, in three cavities present on the external surface of the upper end of the internal plug.

However, it is obvious that such a device is difficult to operate because:

^{• If} it requires a relatively precise mechanical maneuver which consists of an axial pressure to make exactly and simultaneously enter the three teeth into three cavities with a diameter very slightly greater than that of the teeth, which requires good manual skill and a lot of effort so that the opening or closing drive can be carried out;

S the elastic uncoupling means which is a metal spring is calibrated for a very long service life, but few manipulations due to this very particular application, requiring significant human force and particular manual skill when handling it;

this security closure proves to be totally unsuitable for closing containers such as bottles.

Objectives of the invention

Many objectives are therefore assigned to the device according to the invention, so that it can best eliminate the aforementioned drawbacks and that it provides solutions which are improved and improved compared to the various means used in the closure devices. known security.

A first object of the invention is to provide a device for securely closing a container by screwing, child-proof when unscrewing, this device consisting of two plugs of thermoplastic polymers fitted one into the 'other, operating by a means of latching the outer plug on the inner plug by applying an axial pressure-rotation couple, on the upper end wall of the device.

Another object of the invention is to provide a device for securely closing a container by screwing, child-proof when unscrewing, this device comprising a means immediately uncoupling the external driving plug from the internal driving plug, as soon as the pressure exerted on the upper end wall of the device ceases.

Another object of the invention is to produce a device for securely closing a container by screwing, child-proof when unscrewing, the means for which engage and disengage the external drive cap. with the internal plug driven do not undergo, in whole in part, fatigue, permanent deformation or rupture by the repeated application of the torque axial pressure-rotation on the upper end wall of said device.

Another object of the invention is to produce a device for securely closing a container by screwing, child-proof when unscrewing, the means for which engage and disengage the external drive cap. and driven inner cap compensate for adjustment or wear clearances between the outer and inner caps, and give them an excellent cohesion when they are encl ^'iquetés and independence, without play, when they désencliquetés.

Summary of the invention

All the objectives set out above can be achieved by the closure device, object of the invention.

According to the invention, the safety closing device by screwing a container provided with an opening with an external screw thread, is composed of two coaxial plugs, made of thermoplastic polymer materials fitted one inside the other, the one external, the other internal, each formed by a cylindrical side wall and a wall upper end closing the cylindrical side wall,

- The external plug comprising, on its internal surface, latching means allowing it to drive the internal plug in rotation, by the application of a mechanical couple of axial pressure-rotation;

the internal plug comprising a screw thread on the internal surface of its cylindrical side wall and latching means corresponding to those of the external plug on its external surface, allowing it to be driven in rotation by the external plug when the latter is subjected to a mechanical torque of axial pressure-rotation;

- an elastic means for uncoupling the latching means of the internal and external plugs when the application of the mechanical torque axial pressure-rotation on the external plug stops;

means for guiding the internal and external plugs ensuring their coaxiality,

which is characterized in that the elastic means of uncoupling:

- is placed between the upper end walls of the internal and external plugs,

- And is formed from a thermoplastic polymer material with shape memory of different composition from the compositions of the materials constituting the plugs themselves.

More specifically, and according to a first variant, the safety closing device by screwing a container provided with an opening with an external screw thread, which consists of two coaxial plugs made of thermoplastic polymer materials, one inside the other, one external, the other internal, each formed by a cylindrical side wall and an upper end wall closing the wall lateral cylindrical, consists in that:

- The external plug comprises, on the internal surface of its upper end wall, latching means enabling it to rotate the internal plug, by applying a mechanical couple of axial pressure-rotation;

- the internal plug has a screw thread on the internal surface of its cylindrical side wall and latching means corresponding to those of the external plug, on the external surface of its upper end wall, - allowing it to be driven in rotation by the external plug when the latter is subjected to a mechanical torque of axial pressure-rotation; -

- means for guiding the internal and external plugs ensuring their coaxiality and '

- an elastic means for uncoupling the latching means of the upper end walls of the internal and external plugs when the application of the mechanical torque of axial pressure and rotation ceases on the external plug, this elastic means of uncoupling:

• being placed between the upper end walls of the inner and outer caps,

• and being formed of a thermoplastic polymer material with shape memory of composition different from the compositions of the materials constituting the plugs themselves.

More precisely also and according to a second variant, the safety closing device by screwing a container provided with an opening with an external screw thread, which consists of two coaxial plugs made of thermoplastic polymer materials, fitted one into the the other, one external, the other internal, each formed by a cylindrical side wall and an upper end wall closing the cylindrical side wall, consists in that:

- The external plug comprises, on the internal surface of its cylindrical side wall, latching means allowing it to rotate the internal plug, by the application of a mechanical couple of axial pressure-rotation;

- the internal plug has a thread of screws on the internal surface of its cylindrical side wall and latching means corresponding to those of the external plug, on the external surface of its cylindrical side wall, allowing it to be driven in rotation by the external plug, when the latter is subjected to a mechanical torque of axial pressure-rotation; ,

means for guiding the internal and external plugs ensuring their coaxiality and

- an elastic means of uncoupling of the latching means of the cylindrical lateral walls of the internal and external plugs when the application of the mechanical torque of axial pressure and rotation ceases on the external plug, this elastic means of uncoupling: • being placed between the upper end walls of the internal and external plugs,

and being formed of a thermoplastic polymer material with shape memory of composition different from the compositions of the materials constituting the plugs themselves.

Detailed description of the invention

The device according to the invention consists of two plugs, fitted one inside the other, each of these plugs being provided in superstructure with means such as the external plug, when it is subjected to an axial pressure, then a rotation, moves vertically by a downward movement, snaps into the internal plug and drives it in an opening or closing movement on demand.

As soon as the axial pressure ceases on the external plug, the device, to be truly safe, must ensure the reverse upward movement of the external plug, causing the uncoupling of the external and internal plugs: as soon as the external plug is in its disengaged position , and that it is subjected to a single rotation action, it can no longer drive the internal plug in an unscrewing movement.

Such a device is very safe with regard to young children whose coordination of gestures, to simultaneously create the axial pressure-rotation couple necessary for the opening of the device, has not yet been acquired.

The external and internal plugs of the device according to the invention are produced by the methods of plastics processing adapted to their production, using materials which are thermoplastic polymers, such as for example that polyethylenes, polypropylenes, ethylene / propylene copolymers and their mixtures, polyamides, polystyrenes (PS), acrylonitrile-butadiene-styrene copolymers (ABS), styrene-acrylonitrile copolymers (SAN) ), polyvinylchlorides (PVC), polycarbonates (PC), polymethyl methacrylate (PMMA), polyethyleneterephthalates (PET).

According to the invention, and with the great difference from the state of the art, the elastic means with shape memory allowing the opening of the external and internal plugs, as soon as the application of an axial pressure on the external plug stops. followed by a rotation, is formed from an elastic thermoplastic polymer material with shape memory, a composition different from the compositions of the materials used for the manufacture of the external and internal plugs.

The elastic shape memory means can be produced by using at least one thermoplastic elastomer of natural or synthetic origin. The elastomer (s) used may preferably be chosen from the group consisting of elastomers of the natural rubber or synthetic rubber type, in particular the rubbers of mono-olefins, such as, for example, isobutylene / isoprene, ethylene polymers. -vinyl acetate (EVA), ethylene-propylene (EPR), ethylene-propylene-diene (EPDM), ethylene acrylic esters (EMA-EEA), fluorinated polymers, diolefin rubbers, such as, for example, polybutadienes, butadiene-styrene copolymers (SBR), rubbers based on condensation products such as, for example, polyester and polyurethane thermoplastic rubbers, silicones, styrene-styrene-butadiene-styrene (SBS) and styrene rubbers isoprene-styrene (SIS) and others, used alone or as a mixture. The elastic shape memory means can also be produced by means of a thermoplastic polymer foam.

The elastic shape memory means according to the invention may have the form of a volume, preferably of substantially cylindrical, frustoconical, cylindro-frustoconical, cylindro-hemispherical - or hemispherical - type, the diameter of which is adapted to that of the device and whose the height is at least equal to the minimum distance necessary so that the latching means of the external and internal plugs are not in the engaged position.

As already said, the elastic shape memory means according to the invention may have a different volume. This volume can be full and, in this case, be illustrated by a disc, a truncated cone, a dome, or else can be hollow, and in this case, illustrated by a capsule, a truncated cone, a cap, this volume being able to be perforated to limit the effects of suction cup when is practiced, then released the axial pressure (followed by a rotation) on the external plug.

The elastic means according to the invention is placed between the upper end walls of the two plugs: it can be inserted freely between these two walls, or else be equally adherent to the internal surface of the upper end wall of the external plug or to the external surface of the upper end wall of the internal plug, by bonding to the surface of the plug or by overmolding on said plug.

The elastic shape memory means according to the invention, produced by means of thermoplastic polymer materials, can be obtained by one of the means specific to the plastics processing making it possible to manufacture said means.

The latching means are generally known, but must be adapted in their shape according to their location area, due to the presence of the means elastic for uncoupling said latching means according to the invention, placed between the upper end walls of the internal and external plugs.

In the case where the implantation of the latching means is done on the internal surface of the cylindrical side wall of the external plug and on the external surface of the cylindrical side wall of the internal plug, the latching means are generally of known type and do not undergo any transformation: they are, for example, formed:

- blades with a square, rectangular, triangular or other section, present over at least part of the height of said side wall and installed along the generatrices,

- notched crowns present in perimeter on said surfaces concerned.

In the case where the implantation of the latching means takes place simultaneously on the surfaces facing the cylindrical side walls and on the upper end surfaces of said plugs, the latching means are often of known types, such as by example of blades. Such blades, which are described in European patent EP 0631943, form a groove consisting of successive ribs in the form of lamellae extending at least on one of the appropriate surfaces of the upper end walls, in the form of a groove radial, the radial length of each blade must be limited to create a reserve surface, coaxial with the plugs, necessary for the implantation of the elastic means according to the invention.

This radial length is at most equal to the radius of the face of the upper end wall of the external and internal plugs, minus the radius of the base surface. of the geometric volume of the elastic means according to the invention.

In the case where the implantation of the latching means is done on the internal surface of the upper end wall of the external plug and on the external surface of the upper end wall of the internal plug, these means are formed, by example, teeth in a crown, blades with a square, rectangular, triangular or other section, in a radial position, the radial dimension of which is limited to create a reserve surface coaxial with the plugs, necessary for the implantation of the elastic means according to invention.

This radial dimension is preferably at most equal to the radius of the face of the upper end wall of the external and internal plugs, minus the radius of the base surface of the geometric volume of the elastic means according to the invention.

If the latching means are installed on the internal surface of the upper end wall of the external plug and on the external surface "of the upper end wall of the internal plug, these means are formed, for example, teeth in a crown, blades with a square, rectangular, triangular or other section, in a radial position, the radial length of which is limited to create a reserve surface coaxial with the plugs, necessary for the implantation of the elastic means according to the 'invention.

According to the invention, it is possible to install snap-fastening means on the facing surfaces to be provided with them, which have:

- the same morphology as for example teeth mounted in a crown, or radial blades on each of the surfaces of the end walls caps, or perimeter crowns notched on the facing surfaces of the cylindrical side walls of the caps;

- different morphologies, such as for example teeth mounted in a crown on the internal surface of the upper end wall of the external plug and radial blades on the external surface of the upper end wall of the internal plug.

According to a particular variant of the invention, the latching means placed facing each other on the internal surface of the upper end wall of the external plug and on the external surface of the upper end wall of the internal plug are formed on each of these surfaces, by a crown of teeth, the apparent diameter of which is less than that of the plugs, is preferably the same for both of the crowns.

The teeth forming one and the other of the crowns are spaced apart from each other, so that the teeth of the crown of the external plug can easily fit between the teeth of the crown of the internal plug when the external plug is subjected to axial pressure and then to a rotation initiation.

The teeth of the crowns allowing the clipping of the external plug with the internal plug have a form of:

parallelepiped ending at their mechanical engagement end by two oblique, symmetrical planes, separated from each other by a horizontal plane,

parallelepiped or cylinder ending at their end of mechanical engagement by a hemisphere or a truncated cone. This particular shape of the teeth is designed in such a way that the external plug, when not subjected to axial pressure, but only subjected to a rotational movement, can rotate in one direction or the other without causing the internal plug, the teeth of the crown of the external plug being able to slide on the teeth of the crown of the internal plug, if they are in contact with them, without snapping into each other;

- The number of teeth present in each crown essentially depends on the diameter of these crowns: the preferred number of teeth is at least four teeth per crown. Preferably, the ratio of the number of teeth to the diameter in mm of the crown is between 0.15 (4/24) and 0.5 (12/24).

According to the invention, the means for guiding the external plug with respect to the internal plug, to ensure excellent coaxiality, can be present on one and / or the other of the cylindrical side walls of one and the other of the plugs, on the external surface of the internal plug and / or on the internal surface of the external plug.

The guide means can be constituted by blades with square, rectangular, triangular and other sections, presented over all or part of the height of the cylindrical side wall and implanted according to generatrices of said wall.

When these guide means only intervene for this single guide function, they are present on one and / or the other of the cylindrical lateral walls of the external and internal plugs and their height intervenes over all or part of the height of said means. side walls. According to the invention, these guide means can have two functions simultaneously, the first being that of guiding, the second being that of a means for driving the internal plug in the only direction of screwing, by the external plug.

So that these two functions can be performed simultaneously, the blades, constituting the guide and drive means in the screwing direction, are preferably present over the entire height of the cylindrical side walls of the two plugs. These blades have in section substantially the shape of a wave of triangular, rectangular section, the origin of which is located on a generatrix of the cylindrical lateral surfaces, and the end of which is oriented in an oblique plane:

- in the direction of centripetal tendency, when the blades are on the internal surface of the cylindrical side wall of the external plug,

- in the direction of centrifugal tendency, when the blades are on the external surface of the cylindrical side wall of the internal plug.

Thus, when the external plug is subjected to a rotation in the direction of screwing, without any axial pressure, the ends of the guide blades of the external plug come into abutment with the ends of the guide blades of the internal plug and drive the internal plug in the direction of screwing.

Conversely, when the external plug is subjected to a rotation in the direction of unscrewing without any axial pressure, the oblique planes of the guide blades of the external plug slide on the oblique planes of the guide blades of the internal plug without causing said plug internal in the direction of unscrewing. Apart from the only elastic means, which is produced independently of the plugs or by overmolding one of the two plugs, by means of a material different from that used for the plugs, the external and internal plugs, the screw thread , the latching and guiding means are simultaneously produced by mold injection with a polymer material conventionally used for such products.

The invention will be better understood thanks to the numerical description of the figures mentioned below, these figures having only one nonlimiting illustrative nature of a particular device of the invention.

- Figure 1 is a perspective view of the outer plug.

- Figure 2 is a perspective view of an elastic means according to the invention.

- Figure 3 is a perspective view of the internal plug according to the invention.

- Figure 4 is a perspective view of a means for closing a tank containing a moisture-absorbing material.

- Figure 5 is a vertical section of the device according to the invention consisting of external and internal plugs.

- Figure 6 is a horizontal section on B-B of the device according to the invention.

- Figure 7 is an internal view of the external plug of the device according to the invention. - Figure 8 is a vertical section of the external plug of the device according to the invention.

- Figure 9 is a perspective view of a tooth belonging to the latching means according to the invention.

According to FIGS. 1 to 4, the safety closing device according to the invention consists of an external plug (1), an elastic means with shape memory (20), an internal plug (40) and means for closing (60) a reservoir of a hydrophilic material, absorbing the internal humidity of the container (not shown).

The outer plug (1) consists of a cylindrical side wall (2) and an upper end wall (3), closing the cylindrical side wall. On the inner surface of its upper end wall (3) is a latching means (Figure 7) formed of a crown

(4), having a diameter smaller than that of the plug, comprising twelve teeth (5). On the internal surface of the cylindrical side wall, are placed (FIGS. 5, 6, 7) centering means constituted by blades (6) playing simultaneously, in this illustrative case, two functions:

- The first of these functions is that of coaxially guiding the movement of the external plug (1) relative to the internal plug (40), when is applied, then released the axial pressure on the external plug (1);

- The second of these functions is that of participating in a means for driving the internal plug in rotation in the one direction of screwing of the device, in the absence of any axial pressure on the external plug. As illustrated in Figure 6, the blades (6) have substantially, in section, an elongated rectangular shape, the inclination according to the trace of the plane (7) gives an orientation (according to the arrow), in the direction to centripetal tendency and forms an angle "α" with the plane of tangency (8) at the birth of the blade (6).

The internal plug (40) also consists of a cylindrical side wall (41) and an upper end wall (42) closing the cylindrical side wall. On the outer surface of the upper end wall

(42), there is a latching means (Figure 3) formed of a crown (43), of a diameter less than that of the internal plug, but identical to the diameter of the crown

(4) placed on the internal surface of the upper end wall of the external plug (1). The crown (43) has the same number of teeth as the crown (4).

On the external surface of the cylindrical side wall (41), are also placed guide means constituted by blades (45) playing simultaneously (in this illustrative case) two functions:

the first of these functions is that of coaxially guiding the movement of the external plug (1) relative to the internal plug (40),

- the second of these functions is that ^'to participate in a drive means in rotation of the inner cap only in the direction of screwing of the device, in the absence of any pressure axial to the outer cap. As illustrated in Figure 6, the blades (45) have substantially, in section, a triangular shape whose trace of the front plane (46) gives an orientation

(according to the arrow) in the direction of centrifugal tendency and forms an angle "β" with the plane of tangency (47) at the birth of the blade (45).

The shape of the teeth (5, 44) of the crowns (4, 43) is of the rectangular parallelepiped type (FIG. 9) comprising side walls (90, 91) extending at their end of mechanical engagement, during the latching by cut sides (oblique planes) (92, 93), separated from each other by a horizontal plane (94).

This tooth shape is such that, in the absence of axial pressure on the external plug, but during a rotational movement applied to said external plug, the oblique planes (92, 93) of the teeth (5) of the crown (4) and teeth (44) of the crown (43) can slide on each other (in the case of an accidental approach causing their contact), without the teeth of said crowns being able to snap into place and cause 1 drive of the internal plug by rotating the external plug.

Between the upper end walls of the outer and inner plugs is the elastic shape memory means (20) according to the invention (Figure 2). Said elastic means (20) is of the hollow cylindrical-frustoconical type, consisting of a circular crown (21), a cylindrical-frustoconical side wall (22) and a perforated upper end wall comprising a spider ( 23) and openings (24).

The diameter of the elastic shape memory means is smaller than the internal diameter of the snap rings (4) and (43), so that it is easily inserted therein.

The elastic shape memory means, produced by injection molding using a mixture of thermoplastic elastomers, is placed in the operating position between the two walls (3) and (42) of the upper end of the plugs.

The thickness of the elastic shape memory means (20) is very slightly greater than the distance between the end walls (3) and (42), so that, apart from any axial pressure, the external plug ( 1) can be subjected to a rotational movement (in the direction of opening) without driving the internal plug (40).

During an axial pressure on the external plug (1), the elastic shape memory means (20) is compressed, deforms while remaining contained within the limits of the crowns (4) and (43). The deformation by compression of the elastic shape memory means expels the air present in the area allowing the two crowns (4) and (43) to snap into place.

The external plug can rotate the internal plug, in particular in the direction of unscrewing. When the axial pressure ceases, the elastic means with shape memory regains its initial volume, in particular by recovering its initial volume of air. The two plugs, moving away from each other, disengage: the external plug can no longer drive the internal plug, in particular, in the direction of unscrewing.

Complementing the device according to the invention, a cap (60) is present, intended for closing the reservoir (48) (forming part of the internal stopper (40)) into which is introduced a material having specific properties, such as for example to adsorb the internal humidity in the container (not shown) closed by said device.

In the illustrative case mentioned above of the device according to the invention, the device according to the invention is closed by means of the blades (6) and (45) which come into abutment when the external plug (1) is subjected to a single rotational movement in the direction of screwing: the blades (6) of the external plug, driven in the direction of the arrow (49), come into contact with the blades (45) of the internal plug (40) by their abrupt face and drive said internal plug in the closing direction. In the opposite way, the external plug (4) being subjected to a single rotational movement in the direction of unscrewing, according to the arrow (50), the blades (6) slide by their oblique plane (7) on the oblique plane ( 46) of the blades (45): the internal plug is not driven in the unscrewing movement.

In order for the device according to the invention to open by unscrewing, the external plug (1) must be subjected to axial pressure followed by rotation in the direction of unscrewing. In this context, the external plug (1) approaches the internal plug by compressing the elastic shape memory means (20).

The teeth of the crown (4) of the external plug (1) snap into the teeth of the crown (43) of the internal plug (40): the internal plug is then rotated by the external plug (1) and the closure device is easily unscrewed and separated from the container (not shown).

According to another variant (not shown), the safety closing device comprises all the means described in the first illustrative case, except that only the blades (6) exist on the external plug (1) or (45) on the internal plug. (40), blades which intervene for their sole guide function. In this case, the device according to the invention is closed and opened by axial pressure on the external plug followed by an appropriate rotation, causing the crowns (4) and (43) to snap into place and the internal plug (40) to be driven in the direction of application of the rotation on the external plug (1).

Claims

claims

1. Safety closing device by screwing a container provided with an opening with an external screw thread, which consists of two coaxial plugs made of thermoplastic polymer materials, fitted one inside the other, one external, the other internal, each formed by a cylindrical side wall and an upper end wall closing the cylindrical side wall:

the internal plug comprising a screw thread on the internal surface of its cylindrical side wall and latching means corresponding to those of the external plug on its external surface, allowing it to be driven in rotation by the external plug, when this the latter is subjected to a mechanical torque of axial pressure-rotation;

means for guiding the internal and external plugs ensuring their coaxiality,

characterized in that the elastic means of uncoupling: - is placed between the upper end walls of the inner and outer caps,

- Is formed from a thermoplastic polymer material with shape memory, of a composition different from the compositions of the materials constituting the plugs themselves.

2. Safety closing device by screwing a container provided with an opening with an external screw thread, which consists of two coaxial plugs made of thermoplastic polymeric materials, fitted one inside the other, one external, the other internal, each formed by a cylindrical side wall and an upper end wall closing the cylindrical side wall consists in that:

- The internal plug has a screw thread on the internal surface of its cylindrical side wall and latching means corresponding to those of the external plug, on the external surface of its upper end wall, allowing it to be driven in rotation by the external plug, when the latter is subjected to a mechanical torque of axial pressure-rotation;

- means for guiding the internal and external plugs ensuring their coaxiality;

an elastic means for uncoupling the latching means from the upper end walls of the internal and external plugs when ceases the application of the mechanical torque axial pressure-rotation on the external plug, this elastic means of uncoupling:

• being placed between the upper end walls of the internal and external plugs,

• and being formed of a thermoplastic polymer material with shape memory of different composition from the compositions of the materials constituting the plugs themselves.

3. Safety closing device by screwing a container provided with an opening with an external screw thread, which consists of two coaxial plugs made of thermoplastic polymer materials, fitted one inside the other, one external, the other internal, each formed by a cylindrical side wall and an upper end wall closing the cylindrical side wall consists in that:

- the internal plug has a thread of screws on the internal surface of its cylindrical side wall and latching means corresponding to those of the external plug, on the external surface of its cylindrical side wall, allowing it to be driven in rotation by the external plug, when the latter is subjected to a mechanical torque of axial pressure-rotation;

- means for guiding the internal and external plugs ensuring their coaxiality; - an elastic means of uncoupling of the latching means of the cylindrical lateral walls of the internal and external plugs when the application of the mechanical torque of axial pressure and rotation ceases on the external plug, this elastic means of uncoupling:

• and being formed from a thermoplastic polymer material with shape memory different from the compositions of the materials constituting the plugs themselves.

4. Device according to one of claims 1 or 2 or 3, characterized in that the elastic shape memory means is separated from one and the other of the surfaces of the upper end walls.

5. Device according to one of claims 1 or 2 or 3, characterized in that the elastic means with shape memory is integral with one or ^'other of the surfaces of the upper end walls.

6. Device according to one of claims 1 or 2 or 3 and at least one of claims 4 or 5, characterized in that the elastic means with shape memory is produced by means of at least one of the elastic materials with shape memory, chosen from the group consisting of at least one elastomer.

7. Device according to claim 6, characterized in that the elastic shape memory means is produced from materials chosen from the group consisting of elastomers of the rubber type natural and synthetic rubbers used alone or as a mixture.

8. Device according to claim 7, characterized in that the elastic means is preferably made from materials chosen from the group of elastomers formed of isobutylene / isoprene, ethylene-vinyl acetate (EVA), ethylene-propylene (EPR) , ethylene-propylene-diene monomer (EPDM), ethylene-acrylic esters (EMA-EEA), fluoropolymers, polybutadienes, butadiene-styrene copolymers (SBR), polyester and polyurethane rubbers, silicones, styrene rubbers styrene-butadiene-styrene (SBS) and styrene-isoprene-styrene (SIS), used alone or as a mixture.

9. Device according to one of claims 1 or 2 or 3 and 4 to 8, characterized in that the elastic shape memory means has the shape of a volume, of substantially cylindrical, frustoconical, cylindro-frustoconical, cylindro type. - hemispherical - or hemispherical - the diameter of which is adapted to that of the device and the height of which is at least equal to the minimum distance necessary so that the latching means of the external and internal plugs are not in the engaged position.

10. Device according to claim 9, characterized in that the volume of the elastic shape memory means is a full volume.

11. Device according to claim 9, characterized in that the volume of the elastic shape memory means is a hollow volume.

12. Device according to claim 11, characterized in that the hollow volume of the elastic shape memory means is perforated.

13. Device according to one of claims 1 or 2 or 3 and according to at least one of claims 5 to 12, characterized in that the elastic means with shape memory is made integral with one or other of the upper end walls by gluing or overmolding.

14. Device according to one of claims 1 or 2 or 3 and according to at least one of claims 4 or 5 and 8 to 13, characterized in that the elastic shape memory means is produced with a thermoplastic polymer foam .

15. Device according to one of claims 1 or 2 or 3 and according to at least one of claims 4 to 14, characterized in that the thermoplastic polymer material used in the formation of the internal and external plugs is chosen from the group consisting of: polyethylenes, polypropylenes, ethylene-propylene copolymers and mixtures thereof, polyamides, polystyrenes (PS), acrylonitrile-butadiene-styrene (ABS) copolymers, styrene and copolymers acrylonitrile (SAN) polyvinylchlorides (PVC), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethelene terephthalates (PET).

16. Device according to one of claims 1 or 2 and according to at least one of claims 4 to 15, characterized in that, when the implantation of the latching means is done on the internal surface of the wall upper end of the outer plug and on the outer surface of the upper end wall of the inner plug, these means are chosen from those consisting of teeth placed in a crown, blades of square, rectangular, triangular section, in radial position whose radial length is at most equal to the radius of the surface receiving the latching means less the radius of the surface of base of the geometric volume of the elastic means.

17. Device according to one of claims 1 or 2 and according to at least one of claims 4 to 15, characterized in that, when the implantation of the latching means is done simultaneously on the facing surfaces of the side walls cylindrical and on the upper end surfaces of the inner and outer stoppers, the latching means are successive ribs forming blades extending radially on at least one of the appropriate surfaces of the upper end walls of the stoppers in the form a radial groove whose radial length is at most equal to the radius of the surface receiving the latching means minus the radius of the base surface of the geometric volume of the elastic means.

18. Device according to one of claims 1 or 3 and according to at least one of claims 4 to 15, characterized in that, when the implantation of the latching means is done on the internal surface of the cylindrical side wall of the external plug and on the external surface of the cylindrical side wall of the internal plug, the latching means are chosen from the group consisting of blades with square, rectangular, triangular section, present over at least part of the height of said side wall and implanted according to the generators or notched rings present in perimeter on said surfaces concerned.

19. Device according to one of claims 1 or 2 or 3 and according to at least one of claims 4 to 18, characterized in that the latching means located on the facing surfaces of the external and internal plugs are likewise morphology or different morphology.

20. Device according to one of claims 1 or 2 and according to at least one of claims 4 to 16, characterized in that the latching means placed opposite on the internal surface of the upper end wall of the external plug and on the external surface of the upper end wall of the internal plug are formed on each of these surfaces, by a ring of teeth, the apparent diameter of which is less than that of the plugs, is preferably the same for one and the other of the crowns.

21. Device according to claim 20, characterized in that the teeth of the snap-in crowns have the shape of a parallelepiped ending at their mechanical engagement end by two symmetrical oblique planes, separated from each other by a horizontal plane.

22. Device according to claim 20, characterized in that the teeth of the snap-on crowns have a parallelepipedal or cylindrical shape, ending at their end of mechanical engagement by a hemisphere or a truncated cone.

23. Device according to at least one of claims 20 to 22, characterized in that, preferably, the number of teeth present in each crown is at least four teeth per crown, and the ratio the number of teeth at the diameter in mm of the crown is between 0.15 and 0.5.

24. Device according to one of claims 1 or 2 or 3 and according to at least one of claims 4 to 23, characterized in that the means for guiding the external plug with respect to the internal plug are present on the one and / or the other of the cylindrical side walls of one and the other of the plugs, on the external surface of the internal plug and / or on the internal surface of the external plug.

25. Device according to claim 24, characterized in that the guide means consist of blades with square, rectangular, triangular section, present on the cylindrical side wall and implanted according to generatrices of said wall.

26. Device according to one of claims 1 or 2 or 3 and according to at least one of claims 4 to 23, characterized in that the means for guiding the external plug with respect to the internal plug are also and simultaneously drive means in the only direction of screwing the internal plug by the external plug and are preferably present over the entire height of the cylindrical side walls of the two plugs.

27. Device according to claim 25, characterized in that the simultaneous guide and drive means in the direction of screwing of the internal plug by the external plug, are blades having the appearance of a wave of triangular or rectangular section , whose origin is located on a generatrix of the cylindrical lateral surfaces, and whose end is oriented in an oblique plane: - in the direction of centripetal tendency, when the blades are on the internal surface of the cylindrical side wall of the external plug,

- in the direction of centrifugal tendency when the blades are on the external surface of the cylindrical side wall of the internal plug.