Medical valve with positive flow characteristics

Abstract

A medical valve device for use in selectively establishing a fluid flow between first and second medical implements is disclosed. The valve has a body defining a passage from a first port to a second port. The valve defines a first fluid volume when both medical implements are connected thereto, and a second, smaller volume when one of the implements is disconnected, thereby causing a positive flow of fluid from the valve to the second medical implement when the first implement is disconnected.

1 . A medical valve for controlling the flow of fluid between a first medical implement and a second medical implement, said valve comprising a housing having a passage configured for communication with a second medical implement and an opening adapted to receive the first medical implement, a rigid piston positioned within the housing and movable between a first position in which fluid flow is impeded through the housing and a second position in which fluid flow through the housing is facilitated, the passage including a fluid space which automatically and reversibly increases in size when the first medical implement is connected to the valve and which contracts in size when the first medical implement is disconnected to generate a positive flow of fluid in the direction of the second medical implement, the piston further including two o-rings.  
   
   
       2 . The medical valve of  claim 1 , wherein the piston additionally comprises a neck and a head, the neck having a reduced cross-sectional width as compared to the head.  
   
   
       3 . The medical valve of  claim 1 , wherein the passage comprises a first end and a second end, the first end having a smaller diameter than the second end.  
   
   
       4 . The medical valve of  claim 1 , wherein a ledge is positioned within the passage.  
   
   
       5 . The medical valve of  claim 4 , wherein the piston comprises a shoulder which engages the ledge when the sealing element is in the first position.  
   
   
       6 . The medical valve of  claim 1 , wherein the housing comprises at least one screw thread for detachably securing the first medical implement to the valve.  
   
   
       7 . The medical valve of  claim 6 , wherein the at least one screw thread is located on an outside surface of the housing.