Apparatus for reducing fluid drawback through a medical valve

A medical valve for valving fluid, the medical valve having an open mode for permitting fluid flow through the valve, the medical valve also having a closed mode for preventing fluid flow through the valve, the medical valve comprising:

• a housing having an interior wall defining a variable volume fluid chamber for receiving fluid;
• a movable cannula forming at least a part of a fluid passageway through the housing, the cannula having an inlet with an opening, the opening having a size that is substantially the same size as at least a portion of the part of the fluid passageway through the cannula;
• a compressible member within the variable volume fluid chamber,
• the compressible member and interior wall defining a closed chamber volume within the fluid chamber when the valve is in the closed mode,
• the compressible member and interior wall defining an open chamber volume within the fluid chamber when the valve is in the open mode,
• the closed chamber volume being less than the open chamber volume.

A medical valve for valving fluid, the valve permitting fluid flow when in an open mode, the valve preventing fluid flow when in a closed mode, the valve comprising;

• a housing containing a fluid passageway;
• an interior wall defining a chamber, the chamber being within the fluid passageway;
• a compressible member within the chamber, the compressible member having a maximum volume and a minimum volume;
• and
• a movable cannula having an inner passageway that defines a part of the fluid passageway, the cannula having an inlet with an opening, the opening having a size that is substantially the same size as at least a portion of the part of the fluid passageway through the cannula;
• the compressible member having a volume equal to the maximum volume when the valve is in the closed mode;
• the compressible member having a volume equal to the minimum volume when the valve is in the open mode.

A medical valve for valving fluid, the medical valve comprising:

• a housing containing a fluid passageway for directing fluid through the valve, the housing also containing a valve chamber having an inlet for receiving fluid from the fluid passageway;
• movable cannula defining a part of the fluid passageway, the cannula having an inlet with an opening, the opening having a size that is substantially the same size as it least a portion of the part of the fluid passageway through the cannula;
• a compressible member within the chamber, the compressible member dividing the valve chamber into a fluid chamber and a member chamber, the fluid chamber receiving fluid from the inlet and having a fluid outlet for directing fluid to the fluid passageway, the member chamber being defined by the compressible member and a chamber wall;
• and
• a flexible gland member supporting the cannula within the housing.

A medical valve for valving fluid, the medical valve comprising:

• a housing containing a fluid passageway for directing fluid through the valve, the fluid passageway being formed at least in part by a movable channel means for channeling fluid, the movable channel means having an inlet with an opening, the opening having a size that is substantially the same size as at least a portion of the part of the fluid passageway through the movable channel means;
• a valve chamber defined by the housing and being in communication with the fluid passageway;
• and
• means for reducing the volume of the valve chamber.