A CLOSURE FOR A CONTAINER, SUCH AS AN INFUSION BOTTLE

Abstract: A closure for containers, especially for containing liquid infusion or injection mediums, comprises a perforable, elastic sealing body (13) engaging with the neck (10) of the container, and an annular metal cap member (17) for retaining the sealing body on the container neck. In order to prevent the sealing body (13) from being pressed up through the central opening of the cap member (17) when an overpressure is generated within the container, for example during autoclaving, the inner rim portion (23) of the cap member is bent axially inwards into engagement with a radially inwardly directed surface part (24) formed on the upper surface of the sealing body (13). The inner rim of the cap member may then receive the axially directed tension forces, which are generated in the sealing body (13) when overpressure within the container occurs.

Description: A CLOSURE FOR A CONTAINER, SUCH AS AN INFUSION BOTTLE The present invention relates to a closure for closing an opening in a container and comprising a sealing body of a perforable, elastic material, and an annular cap member for compressing and retaining a rim portion of a sealing body between a container sealing surface surrounding the container opening and the cap member- Closures of this type, which may, for example, be used for infusion bottles and for containers adapted to contain an injection medium, are adapted to tightly seal the container opening and to allow discharge of the liquid contents of the container through a hollow needle or cannula of some type, by means of which the elastic sealing body may be perforated . The elastic sealing body may, for example, be of rubber or a suitable plastic material . I n the known closu res of the above type the sealing body comprises a stopper part whjch may be inserted into a container neck so as to tightly engage with the inner surface of the neck, and a flange-shaped rim, which may be com¬ pressed and retained between the annular cap member and the upper edge portion of the container neck defining the container opening. As the sealing body is retained at its rim part only, the stopper part of a conventional cJosure is given a relatively long axial length in order to prevent the sealing body from being pressed upwards through the opening of the annular cap member when a superatmospheric pressure is generated in the container, for example, during autoclaving, or to prevent the sealing body from being pressed downwards into the container neck when perforated by a hollow needle or an infusion set. Furthermore, the bottom side of the stopper part of a conventional closure is formed with an upwardly arched, almost hemispherical sur¬ face assisting in pressing the peripheral outer surface of the stopper part against the adjacent inner surface of the container neck when a superatmospheric pressure occurs in the inner of the container, so as to counteract expulsion of the sealing body from the container neck. OMFL. When such conventional sealing bodies are inserted into the necks of containers filled with an infusion or injection medium, the relatively long stopper parts cause such a compression of the amount of air or gas remaining in the filled container that the overpressure caused by the compression tends to completely or partly expel the stopper part of the sealing body from the container opening, before the sealing body has been fastened to the container neck by means of the annu¬ lar cap member. Especially when the closures are mounted in auto¬ matically operating filling and closing systems, such problems may give rise to serious malfunction . Furthermore, the arched shape of the upper side of the stopper part, which is necessary to avoid expulsion of the sealing body in case of substantial overpressure in the container as mentioned above is, however, disadvantageous in other respects, as the arched shape of the stopper part means an increase of the surface part of the sealing body which may come in direct contact with the liquid contents of the container. This also increases the risk of contamination of the con¬ tainer contents by particles and components which - especially when the sealing member is made from rubber - are inevitably "washed out" during autoclaving from the part of the sealing member surface defining the inner space of the container. In many countries the number of foreign bodies, which may be present in the contents of infusion and injection bottles, are severely restricted. Therefore, it is desirable that the area of the sealing body which may come into direct contact with the container contents, is reduced to a minimum. The present invention provides a closure of the above type, wherein the above disadvantages may be eliminated or reduced, because the length of the stopper part of the sealing body may be reduced to a minimum and possibly totally eliminated, and wherein the part of the sealing body surface which may come into contact with the container contents, may have a flat or substantially plane shape. The closure according to the invention is characterized in that a recess or depression is formed in the outer surface of the sealing body, and that a radially inner rim portion of the annular cap member is bent axially inwards so as to engage with a radially inwardly directed surface part of said recess or depression in the mounted condition of the closure. When an overpressure is generated within the container, for example during autoclaving, and the sealing body is caused to bulge out¬ wards, the radially directed tensions, which are thereby generated in the sealing body, may be received by the inwardly bent rim portion of the cap member, and the rim of the sealing body is thus prevented from being pulled out from the space defined between the cap member and the container sealing surface surrounding the container opening. The additional locking of the sealing body thus provided allows a reduction of the axial length of the stopper part and possibly a total elimination of the stopper part of the closure. Furthermore, the inner surface or lower surface of the sealing body may be substantially plane, which reduces the risk of contamination of the container con¬ tents owing to the reduced contacting surface area. The radially inwardly directed surface part of the sealing body engaging with the inner rim portion of the cap member may possibly consist of a plurality of separated surface portions which may be peripherally spaced along the rim of the sealing body, and the inner rim portion of the cap member may then be divided into a corres¬ ponding number of flaps or fingers, each of which is bent into engagement with a corresponding surface portion . In the preferred embodiment, however, the radially inwardly directed surface part of the recess or depression is annular, because the best guarantee against extraction of the sealing body rim from the space between the cap member and the container sealing surface is obtained thereby. The recess or depression in the outer surface of the sealing body may, for example, be in the form of a central depression or recess having a peripheral, preferably circular, side wall forming the radially inwardly directed surface part, which is normally substan¬ tially cylindrical or conical, but may alternatively have any other curved or angular shape. However, an especially heavy interlocking between the inner rim portion of the cap member and the sealing body is obtained, when the depression or recess is in the form of a channel and a corresponding channel-shaped rib is formed in the inner rim portion of the cap member, and when the walls of this corresponding channel-shaped rib are tightly received in the channel-shaped depression or recess . As mentioned above, the inner surface of the portion of the sealing body covering the container opening is preferably substantially plane, because it is thereby possible to reduce the risk of contamination of the container contents. In case- this advantage is of less importance, the inner side of the sealing body may be shaped in any desired manner and may, for example, have an arched shape like the known closures . Thereby it is possible to reduce the thickness of the sealing body, which has to be perforated when the container content is to be discharged. However, a similar effect may be obtained when a central depression or recess is formed in the outer surface of the sealing body as mentioned above. If the recess or depression receiving the inner rtm portion of the cap member is formed as an annular channel, one or more recesses or depressions may be formed in the central part of the upper surface part of the sealing body, and the position or positions at which the hollow needle or needles is/are to be inserted through the sealing body. The invention will now be further described with reference to the drawings, wherein Fig. 1 shows a side view and partially sectional view of the neck of a container or bottle provided with a closure of the known type, Fig. 2 shows a side view and partially sectional view of the neck of a container or bottle provided with a first embodiment of the closure according to the invention, and Fig. 3 shows a side view and partially sectional view of the neck of a container or bottle, which is provided with a second embodiment of the closu re according to the invention . The drawings show the neck 10 of a container or bottle, for example for containing an infusion or injection medium. The container neck OMPI defines a container opening 11 , which is closed by means of a closure 12 comprising a sealing body 13 made from rubber, soft plastic or another perforable, elastic material . The sealing body has a stopper part 14 projecting into the container neck 10, and a flange-like rim portion 15 engaging with the upper surface 16 of the container 10. An annular cap member 17, which is made from metal, such as alumi¬ nium, or from another suitable material, sealingly retains the sealing body 13 within the container opening, as the upper part 18 of the cap member engages with the upper surface of the sealing body 13, while the lower rim portion 19 of the cap member 17 is bent under a bead 20 formed on the outer surface of the container neck 11 . In the known closure shown in Fig. 1 the stopper part 14 has a relatively long axial length, which means that the sealing member 13 projects quite far into the container neck 10. In the known structure, the underside of the stopper part 14 has a heavily arched shape so as to substantially form a hemispherical surface 21 . Thereby a rela¬ tively small wall thickness is nevertheless obtained at the central portion of the sealing body 13, whereby perforation of the sealing body is facilitated, and, furthermore, the closure is better suited to resist overpressure within the container as explained above. As immediately seen from Fig. 1 , the arched shape of the sealing body means that the container contents may come into contact with a rela¬ tively big surface area of the sealing body 13, which is disadvan¬ tageous as explained above. In the embodiments of the closure according to the invention shown in Figs . 2 and 3, the stopper shaped portion 14 has a relatively short axial length , and the underside 22 of the stopper part is substantially plane or slightly arched, if desired . Thus, the surface area of the sealing body 13 which may come into direct contact with the container contents is substantially reduced, and the plane shape gives the best possibilities for lackering or any other surface treatment of the underside of the stopper part, whereby the risk that foreign matter is transferred from the sealing body to the container contents is further reduced . OMPI In the embodiments shown in Figs . 2 and 3 the inner rim portion 23 of the cap member 17 is formed so that it is in engagement with a radially inwardly directed surface part 24 formed on the upper side of the sealing body 13. Thereby the rim portion 23 of the cap member may receive the radially inwardly directed tensions generated in the sealing body 13 when overpressure is caused in the inner of the container, for example during autoclaving, whereby it is prevented that the rim portion 15 of the sealing body is pulled from the space defined between the upper side 16 of the container neck and the cap member 18, that the sealing body 13 is pressed through the central opening in the cap member 17, and that the sealing body is pressed downwards into the container when the sealing body is perforated by a hollow needle or cannula. In the embodiment shown in Fig . 2 the surface part 24 forms the outer peripheral wall of a channel 25 formed in the upper surface of the sealing body 13, and a corresponding channel-shaped rib 26, which is tightly received within the channel 25, is formed in the inner rim portion 23 of the cap member. In order to facilitate perforation of the sealing body 13, depressions or recesses 27 indicating where perforation of the sealing body must be made when the container contents is to be discharged through a hollow needle or cannula, may also be formed in the upper surface of the sealing body. In the embodiment shown in Fig. 3 the radially inwardly directed surface part 24 forms a peripheral wall of a central depression or recess 28 defined in the upper surface of the sealing body 13, and the inner rim portion 23 of the cap member is then bent into this depression to as to tightly engage with the surface part 24. As indicated in Fig . 3, depressions or recesses 27 serving to facili¬ tate perforation of the sealing body and/or to indicate where such perforation has to be made, may also be present in this embodiment. It should be understod that various modifications of the embodiments shown in the drawings made be made within the scope of the present invention . Thus, it is possible to completely omit the stopper part 14, even though such stopper part is preferred, because it facilitates the OMPI ^*Z radial positioning of the sealing body in relation to the container neck. Furthermore, the radially inwardly directed surface part 24 on the upper surface of the sealing body 13 may be replaced by a plura¬ lity of separated surface portions positioned peripherally spaced, and these surface portions may cooperate with bent flaps formed on the inner rim portion 23 of the cap member 17.

Claims: CLAIMS 1. A closure for closing an opening (11 ) in a container and com¬ prising a sealing body (13) of a perforable, elastic material, and an annular cap member (17) for compressing and retaining a rim portion (15) of the sealing body (13) between a container sealing surface (16) surrounding the container opening (11 ) , and the cap member (17) , characterized in that a recess or depression (25, 28) is formed in the outer surface of the sealing body (13) , and that a radially inner rim portion (23) of the annular cap member (17) is bent axially inwards so as to engage with a radially inwardly directed surface part (24) of said recess or depression in the mounted condition of the closure. 2. A closure according to claim 1 , characterized in that the radially inwardly directed surface part (24) of the recess or depression (25, 28) is annular. 3. A closure according to claim 1 or 2, characterized in that the depression or recess is in the form of a channel (25) , that a corresponding channel-shaped rib (26) is formed in the inner rim portion (23) of the cap member (17) , and that the walls of this corresponding channel-shaped rib (26) are tightly received in the channel-shaped depression or recess (25) . 4. A closure according to any of the claims 1 -3, characterized in that the inner surface of the part of the sealing body (13) covering the container opening (11 ) , is substantially plane. 5. A closure according to any of the claim 1 -4, characterized in that the container is adapted to contain a liquid infusion or injection medium.

Inventors: LUNDBYE EINAR WITTUS, LUNDBYE, EINAR, WITTUS
Applicants: SCHUBERT & CO A S, SCHUBERT & CO. A/S
Application year: 1983
Main classification: B65D41
IPC codes: B65D51