Catheter assembly with seal member

Abstract

A catheter assembly includes a catheter hub defining an interior cavity and a catheter tube extending distally thereof. A rigid actuator extends proximally in the interior cavity and supports a seal member thereon. The seal member includes a central membrane, a distal portion, and a proximal portion. An hourglass shaped actuator cavity is formed in the distal portion and receives a barbed end of the actuator. The outer surface of the seal member is in partial circumferential engagement with the catheter hub to define an air path that allows fluid communication between areas of the interior cavity distal and proximal of the seal member. A punch tool is provided to form a tri-slit in the membrane of the seal member.

Having described the invention, what is claimed is: 
     
         1 . A punch tool for forming a tri-slit of a membrane of a seal member, the punch tool comprising:
 a three-sided pyramid having a base at one end and a pointed tip at an opposite end, the base having three corners;   a shaft extending from the base and having three straight, sharpened edges and generally planar lands between respective pairs of edges, each of the edges being generally axially aligned with a respective one of the three corners of the base.   
     
     
         2 . A method of forming a tri-slit in a membrane of a seal member comprising:
 placing the seal member in a bore of a fixture;   obtaining a punch tool having a three-sided pyramid having a base at one end and a pointed tip at an opposite end, the base having three corners and a shaft extending from the base and having three straight, sharpened edges and generally planar lands between respective pairs of edges, each of the edges being generally axially aligned with a respective one of the three corners of the base;   inserting the punch tool into the fixture to engage the membrane with the pointed tip; and   continuing to insert the punch tool into the fixture to push at least a portion of the pyramid of the punch tool through the membrane.