Patent Description:
Such closure systems comprise a stopper member made of an elastic material and having a plug portion configured to tightly fit into the opening of the container and a cover portion configured to abut a boundary surface adjacent to the opening of the container, and a cage member configured to be mounted to the container. The closure system is configured to be in an assembled state in which the plug portion of the stopper member is fitted into the opening of the container and the cage member is mounted to the container to hold the stopper member. Closure system of this type can be used for tightly and securely closing the opening of the container, in particular, with respect to liquids and gases.

In many chemical or pharmaceutical applications, liquid substances such as drug substances, chemical substances, substances of clinical trials or others are provided in specific containers such as vials, cartridges or the like. These containers typically have a hollow interior and an opening through which the interior is accessible. The opening typically is surrounded or limited by a boundary surface. The substances are filled into the interior of the containers and the openings are subsequently tightly closed.

For closing the containers, it is known to use elastomeric stoppers. Such stoppers may provide for tightly or even hermetically sealing the openings and additionally to allow retrieval of the substances out of the containers by piercing the stoppers with needles and introducing the needles into the substances.

Typically, stoppers have a plug portion and a cover portion, wherein the plug portion is dimensioned to tightly fit into the opening and the cover portion is shaped to abut the boundary surface of the opening. More specifically, the stoppers are pressed into the opening such that the cover portions are compressed to a certain extent to generate tightness. As required in many applications, stoppers and containers of the kind allow for an efficient aseptic filling and closing of the containers. Further, on an industrial scale, containers, such as particularly vials, and stoppers are often dimensioned in predefined sizes. Like this, automated processing with standard equipment can be efficiently implemented.

To achieve a sufficient tightness of the container after filling and closing, the stoppers have to be pressed into and/or onto surfaces of the containers. To hold the stoppers in such compressed state typically caps or cages are used which are arranged on and around the stoppers and openings. For example, it is known to arrange a rigid plastic cap around the head of a vial being closed with a stopper. Thereby, the head and at least part of the neck portion of the vial typically is completely covered by the plastic cap which holds the stopper in the pressed state. Or, it is known to crimp a partially formed metal cap about the head of the container and the cover portion of the stopper to fix and press the stopper to the container (crimp caps).

However, even though such capping systems allow for providing pushing the stoppers, typically it is difficult to accurately define the pressure applied to the stopper. And since the involved components such as vials, stoppers and the like usually involve manufacturing tolerances, automatic assembling of the closure system may result in differently or varyingly pressurizing the stoppers. Thereby, a too low pressure may impair long-term tightness of the closure. Further, a too high pressure may damage the stopper which again will decrease tightness. A closure system is known from <CIT>.

Therefore, there is a need for a device or system that allows for the tight closure of an opening of a container with a pressurized stopper, wherein predefined pressure applied to the stopper can efficiently be assured.

According to the invention this need is settled by a closure system as it is defined by the features of independent claim <NUM>, and by a kit as it is defined by the features of independent claim <NUM>. Preferred embodiments are subject of the dependent claims.

In one aspect, the invention is a closure system for closing an opening of a container. The container can be a container used in pharmaceutical or chemical research, development or production such as a cartridge. It can particularly be a vial.

The term "vial" as used herein can relate to vials in the literal sense, i.e. a comparably small vessel or bottle, often used to store pharmaceutical products or pharmaceuticals or medications in liquid, powdered or capsuled form. The vial can be made of a sterilisable material such as glass or plastic such as, e.g., polypropylene, a cyclic olefin copolymer or a cyclic olefin polymer.

The closure system comprises a stopper member, a cage member and a spring member. The term "member" in this connection and in the context of the following description can relate to a single piece unit. Such single piece unit can be embodied by fixing plural pieces or parts, e.g. made of different materials, together, to a monolithic element made of a single material, or a monolithic element made of one or more materials that are chemically or physically bonded in the manufacturing process such as molding an opaque polymer over a transparent substrate or vice versa.

The stopper member is made of an elastic material. It has a plug portion configured to fit, particularly to tightly fit, into the opening of the container and a cover portion configured to abut a boundary surface adjacent to the opening of the container.

The term "elastic" in connection with the stopper member can relate to properties of the material the stopper member is made of. More specifically, such material properties can be elasto-plastic and, in particular, compressible. Advantageously, the material of the stopper member allows it to be sterilized and to maintain aseptic conditions. The stopper member can be embodied as one piece, i.e. as a monolithic element. The plug portion can be essentially cylindrical such that it matches the geometry of the opening. To allow the cover portion to abut the boundary surface, the cover portion typically laterally or radially projects over the plug portion. It can be more or less disc shaped.

The cage member is configured to be mounted to the container. The closure system is configured to be in an assembled state in which the plug portion of the stopper member is fitted into the opening of the container and the cage member is mounted to the container to hold the stopper member.

The cage member and the spring member are configured to position the spring member between the cover portion of the stopper member and the cage member such that the spring member is arranged to push the cage member away from the cover portion of the stopper member, when the closure system is in the assembled state.

The cage member and the spring member can be configured to position the spring member between the cover portion of the stopper member and the cage member by generating a free space when being in the assembled state. In particular, this free space can be designed to locate the spring member in it and, advantageously, in a predefined alignment such that the spring member acts as intended.

The term "arranged to push the cage member away from the cover portion" in this connection relates to a configuration of the spring member to apply a spring force to the cage member directed away from the cover portion, when the cage member contacts the spring member. Thereby, in particular in the detached position, the cage member can be distant from the spring member such that it does not apply any spring force to the cage member. However, in the fixed position the spring member contacts the cage member and applies the spring force such that the spring member is arranged to push the cage member. More specifically, in the detached position the cage member can be distant to or only touching the spring member and, when moving the cage member relative to the stopper member, the spring member directly or indirectly contacts the cage member and applies its spring force to the cage member, thereby pushing it away from the stopper member. In this state, the spring member applies or transmits a pushing force between the cage member and the cover portion of the stopper member.

By the spring member being arranged to apply a pressure or force to the cover portion of the stopper member in order to push the cover portion of the stopper member onto the boundary surface of the opening of the container, the spring member allows for providing an essentially constant predefined pressure or force onto the stopper member such that irrespective of the precise dimension of the cage member, the stopper member and/or the container, the force by which the cover portion of the stopper member is pressed to the edge of the opening of the container can be accurately set or defined. Such configuration allows for efficiently compensating tolerance variations of the involved components and, at the same time, ensuring tight closure of the container. The force applied to the cover portion of the stopper member can be in a range from about <NUM> Newton (N) to about to about <NUM> N depending on the material characteristics and geometry of the stopper member and other components. For example, it can be about <NUM> N. Like this, the stopper member can be compressed between the stopper push section of the cage member and the boundary surface of the container such that an appropriate tightness between stopper member and container can be achieved and maintained.

Preferably, the cage member has a locking structure configured to engage a corresponding structure of the container, a lid section and in intermediate section between the lid section and the locking structure. When the locking structure engages the corresponding structure, the cage member typically is locked or fixed to the vial. In contrast, when the locking structure disengages the corresponding structure, the cage member typically is not fixed to the vial such that it can be removed from the vial.

The corresponding structure of the container can be a groove or a similar indentation provided at an outer surface of the container. For example, in case the container has a body, a neck and a head with the opening of the container, the groove can be provided at a circumference of the head. Also, the corresponding structure can be an outer shape of the container such as a transition from the head to the neck.

Engaging the corresponding structure can, e.g., be implemented by clipping the corresponding structure. The term "clip" as used herein relates to snapping into or behind the corresponding structure, or a similar mechanism. Generally, such clipping typically involves an elastic deformation or dislocation of one element, such as the cage member, when moving two elements, such as the cage member and the container, together and then elastically deforming the one element back behind a structure of the second element once the two elements are properly positioned. More specifically, for allowing such clipping the clipping element of the cage member can be elastically deformed or bent relative to the other portions of the cage member.

The locking structure allows for providing a snap-fit connection between the cage member and the container. Once clipped or snap-fitted to the container, the cage element may be in a form fit connection with the container. Advantageously, when being clipped to the container or when engaging the corresponding structure of the container, the cage element cannot be removed from the container without being destroyed or broken.

Advantageously, the locking structure of the cage member is configured, in the assembled state of the closure system, to be in a detached position in which the locking structure of the cage member is disengaged from the container, and in a fixed position in which the locking structure engages a corresponding structure of the container. By being capable of assuming the detached and fixed positions, the cage member can efficiently and conveniently be processed, particularly also in an automated manner. For example, the cage member can be mounted to the vial first. In the detached position where it is possible to manipulate the closures system to compress the stopper member. Then, when accurately closing the vial, the locking structure can be changed into the final fixed position.

The locking structure of the cage member preferably comprises at least one positive form lock element configured to be deformed to engage the corresponding structure of the container. Such positive form lock element allows for efficiently and safely securing or locking the cage member to the container. In particular, the at least one positive form lock element may be elastically movable in a radial or outward direction.

Thereby, the at least one positive form lock element of the locking structure of the cage member preferably comprises a tongue portion. The tongue portion can be configured to be radially or centrally moved from the detached position to the fixed position. Such tongue portion allows for providing an efficient and safe locking or fixing of the cage member to the container by engaging the corresponding structure of the container. In particular, a rigidity and elasticity of the locking structure can be suitably configured by means of such a tongue portion.

The tongue portion of the at least one positive form lock element of the locking structure of the cage member preferably extends from the cylindrical intermediate section of the cage member. Such configuration allows for efficiently implementing the locking structure.

The tongue portion of the at least one positive form lock element of the locking structure of the cage member preferably is elastically movable relative to the intermediate section of the cage member. In particular, the positive form lock element can be elastically movable by being at least partially deformed in an elastic manner, i.e., tending to move back to the original shape and/or position. The positive form lock element may allow for some normal relaxation due to material properties.

Advantageously, in order to allow a uniform locking or fixing, the locking structure comprises plural positive form lock elements with or without tongue portions. The number of positive form lock elements or tongue portions can be in a range of about four to twelve, of about four to eight or of about six. Thereby, each of the positive form lock elements or tongue portions can be elastically movable relative to the intermediate section of the cage member. In particular, the cage member can be configured such that, when being fixed to the container, the intermediate section is essentially not deformed but the positive form lock elements or tongue portions are elastically moved. The elastic movability of the positive form lock elements or tongue portions, e.g., can be provided by the positive form lock elements or tongue portions outwardly bending and/or by the positive form lock elements or tongue portions being tilted about a joint portion.

Preferably, the cage member is made of a shape-retentive material. The term "shape retentive" as used in this context relates to a material or structure being capable of maintaining its form when no force is applied. In particular, the shape-retentive material can be dimensionally stable. Typically, shape-retentive materials are comparably rigid. Particularly, the material of the cage member can be more rigid than the material of the stopper member. Also, the shape-retentive material advantageously is sufficiently elastic to allow deformation as described below. Such shape-retentive material can be a plastic or a metal such as, in particular, a steel or stainless steel.

Preferably, the spring member has essentially linear spring characteristics such that it advantageously obeys Hooke's law. The spring characteristics can be essentially linear in this connection when they are linear in a range of compression of the spring member which may be involved in the closure system. By having linear spring characteristics, the spring member has a constant or uniform spring rate more or less independent from its compression. This allows for ensuring a predefined and relatively low range of force to be applied to the stopper that is far less dependent on tolerance variation and the relatively high rate of compression of the stopper (that results in a relative high range of forces).

The intermediate section of the cage member preferably is configured to surround the spring member and at least a portion of the cover portion of the stopper member and/or a head portion of the container, when the closure system in the assembled state. In case the container is a vial or a similar container, the intermediate section can be configured to surround a head of the vial which at least partly comprises the opening and the boundary surface. Thus, the intermediate section of the cage member preferably is configured to surround a head portion of the container. This allows for efficiently holding the stopper in or on the vial and for efficiently mounting the cage member to the container.

The intermediate section of the cage member preferably is essentially cylindrical. Like this, the intermediate section can efficiently be designed to surround the head portion of the container or for other reasons such as asymmetry of interfacing connecting systems such as vial transfer devices. In particular, the intermediate section can have the shape of a small cylinder or ring. The term "small" in connection with the cylinder may relate to a cylinder having a height or axial length which is smaller than a diameter. The cylinder can particularly have a circular cross section.

Preferably, the lid section of the cage member comprises an aperture such that the cover portion of the stopper member is accessible through the aperture of the lid section when the closure system is in the assembled state. The aperture of the cage member can particularly be located adjacent to a surface of the cover portion of the stopper member being in correspondence with the opening of the container when the closure system is in the assembled state. Thereby, the aperture can be aside the section of lid section abutting the surface of the cover section of the stopper member being opposite to the surface contacting the boundary surface of the container. Like this, the accessible portion of the stopper member can be easily accessed and cleaned, e.g., by alcohol swabbing. For example, the aperture of the stopper push section can be a circular central aperture of the stopper push section being a flat ring.

Thereby, the closure system preferably comprises a cover member reversibly mountable to the lid section of the cage member to close the aperture of the lid section of the cage member. Such cover member allows for protecting the cage member. It can be configured to cover the aperture of the cage member when being mounted to the cage member. The cage member can be provided with the aperture to access the cover portion of the stopper member when the closure system is in the assembled state.

Preferably, the cover portion of the stopper member has an edge section with a front face configured to abut the boundary surface of the opening of the container and a back face opposite to and corresponding to the front face of the edge section, wherein the spring member is configured to abut the back face of the edge section of the stopper member when the closure system is in the assembled state. Particularly, the spring member can be configured to abut the essentially complete back face of the edge section of the stopper member. Such complete abutting allows for an efficient and homogenous compression of the stopper member.

Preferably, the cage member is configured to end essentially adjacent to the locking structure when the closure system is in the assembled state. When the container is equipped with a head portion having the boundary surface adjacent to the opening passing over into a neck portion, the cage member can be configured essentially not to extend over the neck portion of the container or to end at the neck portion of the container. Like this, it can be achieved that the neck is kept free which allows an efficient handling of the closed container and attachment to standard or legacy accessories such as transfer kits, and an appropriate optical inspection of the complete interior of the container including the neck.

Preferably, the spring member has an abutting section and at least one elastic lamella, wherein the abutting section is configured, in the assembled state, to abut the cover portion of the stopper member and the at least one lamella to extend from the abutting section to the cage member. In particular, the at least one lamella can extend from the abutting section towards the lid section of the cage member.

Providing the spring member with the abutting section allows for efficiently abutting the stopper at a predefined portion thereof. Thereby, the abutting section can be essentially disk shaped which allows for uniformly and planarly providing the spring pressure to the stopper member.

The abutting section of the spring member can be equipped with an opening. In particular, the opening can be embodied in correspondence with the aperture of the lid section of the cage member such that, in the assembled state, the stopper member can be accessed through the cage member and the spring member.

Preferably, the at least one elastic lamella comprises a plurality of lamellas to allow a more or less spring force distribution towards the stopper member. Furthermore, the lamella(s) can be designed to be bent or collapse when being pushed by the cage member such that, e.g. due the elasticity of the material of the spring member, pushes abutting section away from the cage member towards the stopper member.

Another aspect of the invention is a kit comprising a container and a closure system as described above. The container comprises an opening for accessing an interior of the container and a boundary surface adjacent to the opening.

By means of the kit according to the invention the effects and benefits described above in connection with the closure system according to the invention and its preferred embodiments can efficiently be achieved.

The closure system and kit according to the invention are described in more detail hereinbelow by way of exemplary embodiments and with reference to the attached drawings, in which:.

In the following description certain terms are used for reasons of convenience and are not intended to limit the invention. The terms "right", "left", "up", "down", "under" and "above" refer to directions in the figures. The terminology comprises the explicitly mentioned terms as well as their derivations and terms with a similar meaning. Also, spatially relative terms, such as "beneath", "below", "lower", "above", "upper", "proximal", "distal", and the like, may be used to describe one element's or feature's relationship to another element or feature as illustrated in the figures. These spatially relative terms are intended to encompass different positions and orientations of the devices in use or operation in addition to the position and orientation shown in the figures. For example, if a device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be "above" or "over" the other elements or features. Thus, the exemplary term "below" can encompass both positions and orientations of above and below. The devices may be otherwise oriented, and the spatially relative descriptors used herein interpreted accordingly. Likewise, descriptions of movement along and around various axes include various special device positions and orientations.

<FIG> shows a first embodiment of a kit <NUM> according to the invention comprising a glass or plastic vial <NUM> as container and a first embodiment of a closure system <NUM> according to the invention. In <FIG> the kit <NUM> and closure system <NUM> are depicted in an assembled state where the closure system <NUM> is mounted to the vial <NUM>. The closure system <NUM> is in a detached position.

The vial <NUM> has a body <NUM> with a hollow interior <NUM> and a neck <NUM> passing over into a head <NUM> (not visible in <FIG>) as head portion. The closure system <NUM> is mounted to the head <NUM> of the vial <NUM> such that the head <NUM> is covered. The closure system <NUM> comprises a metal cage <NUM> as cage member and a lid-like cover <NUM> as cover member.

Further, as best visible in <FIG>, the vial <NUM> has a circular or cylindrical opening <NUM> at its head <NUM> which allows to access the interior <NUM> of the body <NUM>. A boundary surface <NUM> adjacent to the opening <NUM> is designed as a flat upwardly oriented surface.

In <FIG> and <FIG> a stopper <NUM> as stopper member and a spring plate <NUM> as spring member of the closure system <NUM> of the kit <NUM> is shown. The stopper <NUM> has an essentially disk- shaped cover portion <NUM> and a plug portion <NUM>. The cover portion <NUM> has a flat top surface onto which the spring plate <NUM> is positioned. In the assembled state, the plug portion <NUM> is tightly fitted into the opening <NUM> of the vial <NUM> provided through the head <NUM> of the vial <NUM>. More specifically, the plug portion <NUM> is dimensioned such that it is radially compressed when being pushed into the opening <NUM> thereby tightening the opening of the vial <NUM>. At the same time, the cover portion <NUM> abuts the boundary surface <NUM> of the vial <NUM>. For ensuring a tight connection between the plug portion <NUM> and the opening <NUM>, the plug portion <NUM> is provided with a circumferential bulge at its outer boundary.

The spring plate <NUM> has has an essentially disk-shaped abutting section <NUM> and six elastic lamellas <NUM>. The abutting section <NUM> is positioned on the flat surface of the cover portion <NUM> of the stopper <NUM> such that it abuts the cover portion <NUM> of the stopper <NUM>. The lamellas <NUM> extend from the abutting section <NUM> more or less diagonally away from the cover portion <NUM>.

As can be seen in <FIG>, the lamellas <NUM> are formed by cutting out sections of the disk of the abutting section <NUM> and bending the thereby formed lamellas <NUM>. In particular, the lamellas <NUM> comprise three outer lamellas <NUM> extending in a counterclockwise radial direction and three inner lamellas <NUM> extending in a clockwise radial direction. Centrally, the abutting section <NUM> is provided with circular opening allowing to access the stopper <NUM> when the spring plate <NUM> is positioned on the cover portion <NUM> of the stopper <NUM>.

The closure system <NUM> of the kit <NUM> further comprises a lock activation formation. <FIG> shows a surrounding member <NUM> of the lock activation formation arranged on the cage <NUM>.

The cage <NUM> of the closure system <NUM> is made of a rigid but to a certain extent elastic metallic material such as stainless steel. It has a more or less disk-shaped lid section <NUM> with a central aperture <NUM> and a plurality of positive form lock elements as a locking structure, each having a downwardly extending tongue <NUM>. Further, the cage <NUM> has a detent structure with a plurality of downwardly extending clamping elements <NUM> configured to clamp the head <NUM> of the vial <NUM> in the assembled state of the closure system <NUM>. More specifically, from the lid section <NUM>, an essentially cylindrical intermediate section <NUM> (not visible in <FIG>) downwardly extends which in turn passes over into downwardly extending tongues <NUM> and the downwardly extending clamping elements <NUM>. The tongues <NUM> and the clamping elements <NUM> are regularly and alternately distributed about the intermediate section <NUM>.

The surrounding member <NUM> is essentially crown-shaped. In particular, it consists of a ring <NUM> from which six blades <NUM> upwardly extend. The blades <NUM> correspond to the through holes <NUM> of the cover <NUM>. The surrounding member <NUM> is made as one piece of stainless steel. The blades <NUM> of the surrounding member <NUM> are aligned with the clamping elements <NUM> of the cage <NUM>. Accordingly, the tongues <NUM> are arranged at the sections of the ring <NUM> not being provided with the tongues <NUM>.

As can be best seen in <FIG> and, particularly, <FIG>, the cover <NUM> has a ring portion <NUM> dimensioned to partially surround the cage <NUM> when being mounted to the vial <NUM>, and a circular disk portion <NUM> dimensioned to close a top side of the cage <NUM>. The disk portion <NUM> radially projects over the ring portion <NUM> such that a flange portion <NUM> is established. Adjacent to the flange portion <NUM> six slit-like through holes <NUM> are regularly arranged around the cover <NUM>. Further, the disk portion <NUM> is provided with a central indentation <NUM> to receive a portion of the cage <NUM> as described in more detail below.

<FIG> shows the closure system <NUM> near the head <NUM> of the vial <NUM> in the assembled state, wherein the closure system <NUM> is in the detached position. There, the clamping elements <NUM> clamp the head <NUM> of the vial <NUM> such that the closure system <NUM> is held on the vial <NUM>. The plug portion <NUM> of the stopper <NUM> is fitted into the opening <NUM> of the vial <NUM>. It is equipped with a dome-shaped downwardly open cavity. The cover portion <NUM> of the stopper <NUM> abuts the boundary surface <NUM> of the vial <NUM>. In the detached position, the spring member <NUM> located on the top surface of the cover portion <NUM> does not contact the cage <NUM> or its lid section <NUM>, respectively. Thus, the cover portion <NUM> of the stopper <NUM> is not pushed by the cage <NUM> such that it is not compressed between the lid section <NUM> and the boundary surface <NUM>. In this situation, the cover portion has a first height H<NUM>.

The surrounding member <NUM> of the lock activation formation <NUM> is positioned around the intermediate section <NUM> of the cage <NUM>. More specifically, the ring <NUM> of the surrounding member <NUM> is dimensioned to fit to the cage <NUM> such that it is held by friction on the cage <NUM>. The cage <NUM> is in the detached position in which it is not fixed but releasably held to the vial <NUM>. In this detached position, the tongues <NUM> of the locking structure downwardly protrude the surrounding member <NUM> and do not engage or do disengage the vial <NUM>. Further, the tongues <NUM> are essentially L-shaped having a straight leg section and a straight foot section. The leg section downwardly extends from the intermediate section <NUM> of the cage <NUM>. Thereby, the leg sections of the tongues are not parallel to an axis of the vial <NUM> but aligned at an acute angle relative to the axis. Each leg section of the tongues <NUM> passes over into the foot section at its bottom end, wherein the foot sections and the leg sections are more or less at a right angle relative to each other.

The ring portion <NUM> of the cover <NUM> is arranged around the surrounding member <NUM> of the lock activation formation <NUM>, wherein it is dimensioned to be held by friction. At a lower face of the disk portion <NUM> the indentation <NUM> receives a corresponding circular bulge <NUM> of the lid section <NUM> of the cage <NUM> surrounding the circular aperture <NUM>.

<FIG> shows that the lock activation formation further comprises an activator <NUM>, here in a non-activating position. The activator <NUM> has a plate-like base equipped with downwardly extending clipping arms <NUM> and downwardly extending blades <NUM> adjacent to and corresponding to the six through holes <NUM> of the cover <NUM>. In the assembled state, the clipping arms <NUM> are clipped or snap-fitted behind the flange portion <NUM> of the cover <NUM> such that the activator <NUM> is secured to the cover <NUM>. By having the blades <NUM>, the activator <NUM> is shaped to access the surrounding member <NUM> of the locking structure through cover <NUM>. The blades <NUM> of the surrounding member <NUM> extend bottom up through the through holes <NUM> of the cover <NUM>. The blades <NUM> of the activator <NUM> are positioned adjacent to and on top of the blades <NUM> of the surrounding member <NUM>. Further the activator <NUM> is equipped with four downwardly extending inclined or diagonal lamellas (not visible in the Figs. ) as spring or support members. The lamellas are positioned between the activator <NUM> and the cover <NUM> such that the activator <NUM> is pushed away from the cover <NUM> and the cage <NUM>.

In <FIG> the closure system <NUM> is shown near the head <NUM> of the vial <NUM> in its assembled state, wherein the cage <NUM> is in a fixed position. The cover <NUM> is pressed on the cage <NUM> which in turn pushes the spring member <NUM> located on the top surface of the cover portion <NUM> of the stopper <NUM>. Thereby, the elastic lamellas <NUM> are continuously bent towards the cover portion <NUM> of the stopper <NUM>, i.e. the lamellas are collapsing, wherein the linear spring characteristics of the spring member <NUM> assure that the spring force applied by the abutting section <NUM> of the spring member <NUM> to the cover portion <NUM> of the stopper <NUM> is constant and independent from a level of collapse of the lamellas <NUM>. Like this, it is achieved that independent of the exact level of pushing the cage <NUM> relative to the stopper <NUM>, a predefined compression force, which corresponds to the spring force of the spring member <NUM> and which may be about <NUM> N, is applied to the cover portion <NUM> of the stopper <NUM>. Thus, the cover portion <NUM> is compressed to a predefined extent between the lid section <NUM> of the cage <NUM> and the boundary surface <NUM> of the vial <NUM>. When being compressed like this, the cover portion <NUM> of the stopper <NUM> has a second height H<NUM>, which is smaller than the first height H<NUM>. Like this, the spring member <NUM> compensates manufacturing tolerances potentially involved in any of the components of the kit <NUM> such that an appropriate tightness between the vial <NUM> and the stopper <NUM> can be established and it can be assured that the stopper <NUM> is not damaged due to excessive compression.

The tongues <NUM> of the locking structure of the cage <NUM> are downwardly moved relative to the vial <NUM> and the surrounding member <NUM> of the lock activation formation <NUM> is downwardly moved relative to the cage <NUM>. Thereby, the surrounding member <NUM> interacts with the tongues <NUM>, i.e. contacts the tongues <NUM> and inwardly bends them towards the axis of the vial <NUM> being aligned with an axis of the closure system <NUM>. More specifically, the tongues <NUM> are deformed such that their leg sections are essentially parallel to the axis of the vial <NUM> and their foot sections grip or engage the lower end of the head <NUM> of the vial <NUM> as corresponding structure of the vial <NUM>. The surrounding member <NUM> holds and secures the tongues <NUM> in this position. Thereby, a form-fitted connection between the cage <NUM> and the vial <NUM> is generated such that the cage <NUM> is locked on the vial <NUM> and the stopper <NUM> is secured in the compressed state.

<FIG> shows that, for locking the closure system <NUM> to the vial <NUM>, the activator <NUM> of the lock activation formation <NUM> is downwardly pushed from the non-activating position into an activating position. Thereby, the lid section <NUM> of the cage <NUM> is moved towards the cover portion <NUM> of the stopper <NUM> as described above. The activator <NUM> is downwardly moved relative to the cage <NUM> and vial <NUM>. Thereby, the blades <NUM> of the activator <NUM> are moved top down into the through holes <NUM> of the cover <NUM>. The blades <NUM> of the surrounding member <NUM> are contacted such that the surrounding member <NUM> is downwardly moved relative to the cage <NUM> which in turn inwardly moves the tongues <NUM> to lock the cage 32on the vial <NUM> as described above. Like this, the lock activation formation <NUM> interacts with the cage <NUM> to change the cage <NUM> from the detached position to the fixed position.

This description and the accompanying drawings that illustrate aspects and embodiments of the present invention should not be taken as limiting-the claims defining the protected invention. In other words, while the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. In some instances, well-known circuits, structures and techniques have not been shown in detail in order not to obscure the invention. Thus, it will be understood that changes and modifications may be made by those of ordinary skill within the scope of the appended claims.

Claim 1:
A closure system (<NUM>) for closing an opening (<NUM>) of a container (<NUM>), comprising
a stopper member (<NUM>) made of an elastic material and having a plug portion (<NUM>) configured to fit into the opening (<NUM>) of the container (<NUM>) and a cover portion (<NUM>) configured to abut a boundary surface (<NUM>) adjacent to the opening (<NUM>) of the container (<NUM>), and
a cage member (<NUM>) configured to be mounted to the container (<NUM>),
wherein the closure system (<NUM>) is configured to be in an assembled state in which the plug portion (<NUM>) of the stopper member (<NUM>) is fitted into the opening (<NUM>) of the container (<NUM>), the cover portion (<NUM>) of the stopper member (<NUM>) abuts the boundary surface (<NUM>) of the container (<NUM>) and the cage member (<NUM>) is mounted to the container (<NUM>) to hold the stopper member (<NUM>),
characterized by further comprising a spring member (<NUM>)
wherein the cage member (<NUM>) and the spring member (<NUM>) are configured to position the spring member (<NUM>) between the cover portion (<NUM>) of the stopper member (<NUM>) and the cage member (<NUM>) such that the spring member (<NUM>) is arranged to push the cage member (<NUM>) away from the cover portion (<NUM>) of the stopper member (<NUM>), when the closure system (<NUM>) is in the assembled state.