AN INJECTION SYRINGE FIXTURE WITH AN ADAPTER MEANS FOR PREPARATION CONTAINERS.
A fixture for receiving an injection syringe and of the type adapted to cooperate with an adapter device, which is integral with the fixture, for coupling with a container means, such as a vial or a cartridge.
Various devices are known for use in connection with mixing of preparations and solvents. An example is a product having the name Soluject^, which consists of an assembled and closed unit comprising preparation, solvent and syringe. This structure is intended to pro¬ vide a completely sterile system to ensure correct volume, concentration and thus dosage.
This structure includes a so-called intermediate member which connects syringe and container means, and the overall unit thus adapted also serves as a disposable package.
Known are likewise devices which are adapted to receive the injection syringe itself, the devices being re-usable by repeated coupling with optionally different forms of preparation containers.
However, so far it has been a problem that injection of solvent into the vials may cause formation of foam, and it will be appreciated that this is extremely un¬ desirable and may be downright dangerous. Since, following substantially homogeneous mixing, preparation and solvent are sucked back into the injection syringe via the needle, any present air bubbles will tend to be entrained in the suction flow into the injection syringe, which reduces the dosage accuracy, and which may likewise cause severe discomfort to patients in the following injection.
The object of the invention is to provide a fixture which ensures correct cooperation between injection and prepa¬ ration container so that the risk of foam formation when mixing preparation and solvent is avoided.
This object is achieved by providing a fixture as defined in the characterizing portion of claim 1. When the adapter of the fixture is formed with an opening inclined with respect to the axis of the injection syringe, the needle of the injection syringe, when penetrating the associated preparation container, will be placed against the plug or sidewall of said container so that the ray path of the solvent is interrupted. The risk of foam formation is thus eliminated completely.
The adapter device of the fixturecan of course be formed in various ways in connection with temporary attachment of varying embodiments of vials, cartridges as well as other container types.
Such a structure where a fixture retains and mutually positions an injection syringe and a vial provides a safeguard precisely against the drawbacks and risks which are known e.g. from the US Patent Specification 3 332 421, which describes an injection syringe and a container unit where the former in the package or storage state is coupled with the container. In the mixing operation the syringe is removed and passed manually through a casing/cover means. It is readily evident that the use of this device does not in any way prevent formation of foam. E.g., the position of the injection needle with respect to the container will be arbitrary. Moreover, this structure has quite clearly problems in terms of strength when the injection needle is engaged with the container, which may quite evidently interfere with injec¬ tion and backward suction so that foam formation easily occurs.
The invention will be explained more fully by the follow¬ ing description of a preferred embodiment with reference to the drawing, in which
fig. 1 is a lateral, longitudinal, partially sectional view of a fixture according to the invention, in which an injection syringe is positioned, and which has mounted thereon a vial, and
fig. 2 is a top, likewise partially sectional view of the fixture illustrated in fig. 1.
The figures show a fixture 1 according to the invention, and it appears that the preferred embodiment shown here consists of two parts, namely an internal fixture part 3 and an external fixture part 2. The two fixture parts are mutually slidable in the longitudinal direction, and are adapted to receive an injection syringe 7; it will be appreciated that mounting of the injection syringe in the fixture requires initial extension of the internal fixture part 3 from the fixture part 2, so that the injec¬ tion syringe is placed on the inner fixture part with its bottom firmly engaged with the rear member 4 of the outer fixture part.
It will likewise be seen that the fixture 1, at its oppo¬ site end, is provided with an adapter device 9 for re¬ ceiving a container means 13, such as a vial or a cart- ridge, adapted to cooperate with the needle 8 of the injection syringe. For mixing of preparation substance and solvent, it will therefore be appreciated that the internal fixture part 3 is moved into the external fixture part 2 until the needle 8 of the injection syringe 7 has penetrated the seal 12 of the vial and the needle has assumed a position in the immediate vicinity of the internal sidewall 14 of the vial 13. In this mutual po¬ sition of injection needle and vial the two parts of
the fixture are locked, the side faces of said parts being provided with mutually cooperating snap locking means 5 and 6 to provide the proper conditions for the mixing process.
In this mutual position of the parts the introduction of solvent from the injection syringe to the vial may be initiated, and since the adapter means 9 is provided with an angularly displaced opening 10, it will be seen that the needle is disposed in the above-mentioned posi- tion close to the internal container wall 14. During transfer of solvent in the container 13 the solvent will contact said wall immediately after emerging from the needle point of the injection syringe 7. Thus, no dis¬ turbing movements are imparted to the solvent, which may cause foam formations and air bubbles which, when the preparation solution is subsequently sucked up, may be extremely dangerous in connection with subsequent injection of patients.
The adapter device of the fixture may be provided in various ways within the scope of the invention so that it is optionally adapted to various forms of preparation containers, and also the inclination of the adapter ope¬ ning may be adapted to these various embodiments.