Patent ID: 8074652
Filing Date: 2011-12-13
Classification: A61M

Abstract:
1. A method of forming a cannula comprising the steps of: assembling a cannula mandrel assembly comprising separable engageable parts including a facepiece mandrel and a pair of mouthpiece/nasal mandrels, an intermediate section of the facepiece mandrel being provided with a pair of spaced apart through holes for each receiving a remote free end of one of the mouthpiece/nasal mandrels and allowing the facepiece mandrel to slide along the pair of mouthpiece/nasal mandrels, and each of the mouthpiece/nasal mandrels having a stop feature, with a larger transverse cross section, which prevents further sliding movement of the facepiece mandrel along the pair of mouthpiece/nasal mandrels and while also avoiding flow of a polymeric material between the facepiece mandrel and the mouthpiece/nasal mandrels; heating the cannula mandrel assembly to a desired temperature; providing an uncured polymeric material in flowable state; applying at least one coating of the uncured polymeric material to the cannula mandrel assembly to provide a desired material thickness coating on the cannula mandrel assembly; at least partially curing the coating of the polymeric material on the cannula mandrel assembly to form the cannula; disassembling the cannula mandrel assembly by first sliding both the facepiece mandrel and the formed cannula along the mouthpiece/nasal mandrels toward the remote free ends of the mouthpiece/nasal mandrels until the facepiece mandrel and the partially cured cannula are completely removed from the pair of mouthpiece/nasal mandrels; and then withdrawing the facepiece mandrel from the formed cannula.