ALL PLASTIC CANNULA
A dispensing system is formed entirely from plastic materials. The system allows for the closed loop transfer of fluid from a vial to a syringe relying a diaphragm that is captured between a frame and a connector element. The connector element includes a bellows sleeve with a resilient top panel that is penetrated by a cannula and/or needle when fluid is withdrawn, whereas the diaphragm may expand or contract in response to pressure differentials created as the fluid is transferred.
1 . A dispensing system for closed loop dispensing of fluids, the system comprising:
a fitment with a first facing configured to hermetically seal to an opening in a fluid container and an opposing facing configured to receive a syringe;
wherein the fitment comprises:
a frame having a base section axially separated from a closure cap by a plurality of arms;
a connector having: i) a bellows sleeve engaging an aperture in the closure cap by way of a resilient end panel, ii) an outer skirt configured to be coaxially received within the base section, and iii) an inner skirt configured to releasably couple to the syringe;
a diaphragm positioned between the frame and the connector and configured to contract and/or expand between interstices between the arms in response to pressure differentials within the system; and
a cannula coaxially received within the inner skirt and a portion of the bellows sleeve; and
wherein a central aperture is formed in each of the frame, the connector, and the diaphragm so as to allow for movement of components therethrough.
2 . The system of claim 1 wherein the frame and the connector are snap-fitted.
3 . The system of claim 1 wherein the fitment is constructed entirely from non-metallic components.
4 . The system of claim 3 wherein the non-metallic components consistent of thermoplastics and/or elastomers.
5 . The system of claim 1 wherein the frame further comprises a trocar element positioned coaxially within and extending axially out of the closure cup.
6 . The system of claim 1 further comprising a sealing assembly engaging the first facing of the fitment.
7 . The system of claim 6 wherein the sealing assembly includes at least one of a plug and an overcap.
8 . The system of claim 6 wherein the closure cap includes coupling features engaging the sealing assembly.
9 . The system of claim 1 wherein the cannula includes attachment flanges positioned on a main body section of the cannula opposite from a probe section.
10 . The system of claim 1 wherein at least three arms are spaced apart equally and curve upwardly and radially inwardly to connect to the closure cap.
11 . The system of claim 1 wherein the connector includes a mounting extension.
12 . The system of claim 1 wherein a tip of the syringe engages the cannula and advances the cannula so as to penetrate the end panel to allow for fluid to be drawn into the syringe, with the interior volume enclosed by the diaphragm preventing leakage or vaporization loss of the fluid to the ambient environment.