Abstract: An implantable infusion device includes a housing having opposite first and second walls and a relatively large blind passage extending into the housing from the first wall toward the second wall. A first self-sealing septum blocks the passage at the first wall and a second self-sealing septum blocks the passage at a location therein spaced from the first septum thereby defining an infusate chamber between the first and second septa and a blind chamber between the second septum and the housing second wall. A fluid pathway containing a normally closed valve extends from the infusate chamber to the exterior of the housing and a lever connected to the valve is located in the blind chamber. That lever may be depressed to open the valve only by a needle inserted through the two septa into the blind chamber which needle has a side opening aligned with the infusate chamber when such depression occurs.

Abstract: An improved infusion device is of the type which can be implanted for drug delivery within a patient's body, and supplied with infusate without the need for surgical removal. The infusion device has a housing forming a chamber and an entry port into the chamber. The entry port is closed by a septum. The septum has a convex top section extending from the housing, and a frusto-conical section which matingly engages a similarly shaped interior surface of the housing. The interior surface can be provided with a plurality of notches with which the septum engages by material flexure. This arrangement improves retention of the septum and operation of the infusion device, and permits advances in the method by which such devices are manufactured.