Anti-drawback medical valve
A medical valve has an open mode that permits fluid flow, and a closed mode that prevents fluid flow. Among other things, the medical valve includes a housing forming an interior having a fluid chamber, and a valve mechanism within the interior. The valve mechanism has a movable member that includes a needle (e.g., a hypetube). The needle may extend into the fluid chamber when the valve is in the open mode.
1. A medical valve having an open mode that permits fluid flow, and a closed mode that prevents fluid flow, the medical valve comprising:
a housing forming an interior having a fluid chamber;
a valve mechanism within the interior,
the valve mechanism having a movable member,
the movable member including a needle that extends into the fluid chamber when the valve is in the open mode, the entire needle moving as the valve transitions from the open mode to the closed mode,
wherein the valve has neither a positive push nor a drawback when the valve transitions from the open mode to the closed mode.
2. The medical valve as defined by claim 1 wherein the movable member forms a fluid channel that is open when in the open mode, and closed when in the closed mode.
3. The medical valve as defined by claim 1 wherein the needle is a tube.
4. The medical valve as defined by claim 1 wherein the needle is at least a part of a cannula.
5. The medical valve as defined by claim 1 wherein the needle has a side wall that terminates at a closed distal end, the side wall forming a hole that is occluded by the valve mechanism when in the closed mode.
6. The medical valve as defined by claim 5 further including a member that occludes the hole when in the closed mode.
7. The medical valve as defined by claim 1 further wherein the valve mechanism includes a gland circumscribing at least a portion of the movable member.
8. The medical valve as defined by claim 1 wherein the housing forms a proximal port, the valve mechanism forming a seal at the proximal port when in the closed mode, the valve mechanism also forming a seal within the interior of the housing when in the closed mode.
9. The medical valve as defined by claim 1 wherein the needle is a hypotube.
10. The medical valve as defined by claim 1 wherein the entire needle moves longitudinally as the valve transitions from the open mode to the closed mode.
11. A medical valve having an open mode that permits fluid flow, and a closed mode that prevents fluid flow, the medical valve comprising:
a housing forming a proximal port and a distal port, the housing also having a fluid chamber positioned closer to the distal port than to the proximal port;
a valve mechanism between the proximal port and distal port,
the valve mechanism having a movable member with a movable needle that extends into the fluid chamber when the valve is in the open mode,
the needle having a side wall that terminates at a closed distal end, the side wall forming a hole that is normally occluded by the valve mechanism,
the valve having neither a positive push nor a drawback when the valve transitions from the open mode to the closed mode.
12. The medical valve as defined by claim 11 further including a proximal seal adjacent the proximal port, the proximal seal being substantially flush with the proximal port.
13. The medical valve as defined by claim 11 wherein the needle is a tube.
14. The medical valve as defined by claim 11 wherein the valve mechanism includes a member that occludes the hole when in the closed mode.
15. The medical valve as defined by claim 11 further wherein the valve mechanism includes a gland circumscribing at least a portion of the movable member.
16. The medical valve as defined by claim 11 wherein the entire needle moves longitudinally as the valve transitions from the open mode to the closed mode.