Fluid transfer devices with sealing arrangement
The present invention is directed toward fluid transfer devices including a vial adapter having a top wall and a cannula with a cannula tip, and an elastic O-ring like sealing element sealingly encircling the cannula and initially disposed towards the cannula tip and spaced apart from the top wall, the sealing element being brought into initial contact with the vial stopper subsequent to the cannula tip contacting the vial stopper at a puncture site and thereafter being slidingly urged towards the top wall and continuously sealing the puncture site during snap fit mounting the vial adapter on the vial.
1. A fluid transfer device for use with a medicinal vial having a longitudinal vial axis and including a vial body having a vial interior for storing a medicament, a vial rim defining a vial opening, a narrow neck intermediate the vial body and the vial rim, a vial stopper sealing the vial opening and having a stopper thickness T close to the vial axis, the vial stopper having an uppermost stopper surface, the fluid transfer device comprising:
a) a vial adapter having a longitudinal adapter axis and including a top wall transverse to said adapter axis, a downward depending skirt with flex members configured to be snap fitted onto the vial rim for concentric mounting of said vial adapter on the vial, a tubular cannula having a pointed tip configured to initially contact the vial stopper at a puncture site and puncture therethrough for establishing flow communication with the vial interior on said snap fit mounting, and a flow communication channel in flow communication with said cannula; and
b) an elastic O-ring like sealing element sealingly encircling said cannula and being slidably disposed on said cannula, said sealing element being initially disposed along said cannula and spaced apart from said top wall and said pointed tip to leave a first exposed cannula length L between said sealing element and said pointed tip and a second exposed cannula length between said sealing element and said top wall, said first exposed cannula length L being shorter than said stopper thickness T such that said sealing element contacts the vial stopper prior to said cannula puncturing therethrough, said sealing element being configured to be brought into initial contact with the vial stopper subsequent to said pointed tip contacting the vial stopper at said puncture site and to be thereafter slidingly urged on said cannula toward said top wall and continuously seal said puncture site during said snap fit mounting of said vial adapter on the vial.
2. The device according to claim 1 , wherein said sealing element includes a tubular main body and a converging tubular leading section facing towards said pointed tip.
3. The device according to claim 1 , wherein said sealing element deforms in a radial direction when axially compressed between said top wall and the uppermost stopper surface.
4. The device according to claim 1 , wherein said sealing element has a hardness rating less than 50 Shore A.
5. The device according to claim 1 , wherein said sealing element has a hardness rating in a range of 5 to 35 Shore A.
6. A fluid transfer device for use with a medicinal vial having a longitudinal vial axis and including a vial body having a vial interior for storing a medicament, a vial rim defining a vial opening, a narrow neck intermediate the vial body and the vial rim, a vial stopper sealing the vial opening and having a stopper thickness T close to the vial axis, the vial stopper having an uppermost stopper surface and an opposing bottommost stopper surface, the fluid transfer device comprising:
a) a vial adapter having a longitudinal adapter axis and including a top wall transverse to said adapter axis, a downward depending skirt with flex members configured to be snap fitted onto the vial rim for concentric mounting of said vial adapter on the vial, a tubular cannula having a pointed tip configured to initially contact the vial stopper at a puncture site and puncture therethrough to establish flow communication with the vial interior on said snap fit mounting, and a flow communication channel in flow communication with said cannula; and
b) an elastic O-ring like sealing element sealingly encircling said cannula and being configured to slide on said cannula, said sealing element being initially disposed along said cannula and spaced apart from said top wall and said pointed tip to leave an exposed cannula length L between said sealing element and said pointed tip, said sealing element being configured to be brought into initial contact with the vial stopper subsequent to said pointed tip contacting the vial stopper at said puncture site and to be thereafter slidingly urged on said cannula toward said top wall and continuously seal said puncture site during said snap fit mounting of said vial adapter on the vial, such that said sealing element is configured to contact the uppermost stopper surface before the pointed tip pierces the bottommost stopper surface to prevent vacuum leakage.
7. The device according to claim 6 , wherein said sealing element includes a tubular main body and a converging tubular leading section facing towards said pointed tip.
8. The device according to claim 6 , wherein said sealing element deforms in a radial direction when axially compressed between said top wall and the uppermost stopper surface.
9. The device according to claim 6 , wherein said sealing element has a hardness rating less than 50 Shore A.
10. The device according to claim 6 , wherein said sealing element has a hardness rating in a range of 5 to 35 Shore A.