Endoscope valve assembly
An air-water valve assembly is provided for regulating the flow of both water and air through an endoscope. The valve assembly includes a tripartite stem having a plurality of seals disposed thereon and a hub configured to releasably couple the valve assembly to an endoscope for an endoscopic procedure. The stem includes a lower stem member, an upper stem member, and a cap that may be coupled together in a variety of configurations. Each of the lower stem member, upper stem member, and the cap may include a channel or bore extending therethrough to permit fluid communication between a distal opening of the lower member and an aperture of the cap once the stem is assembled.
1 . An endoscope having an air-water endoscope valve assembly, said assembly comprising:
a tripartite stem comprising:
a lower stem member having an axially oriented proximal opening, a transversely oriented distal opening, and a channel extending therebetween, and further having a lower stem shoulder disposed between said axially oriented proximal opening and said transversely oriented distal opening, and a distal extension having a proximal seal seat and a distal seal seat;
an upper stem member having an axial bore extending therethrough, and further having an upper stem shoulder and an upper stem seal seat, wherein the upper stem member is configured to receive the lower stem member within the axial bore to couple the upper stem member thereto; and
a cap integrally coupled to the upper stem member, the cap including an aperture permitting fluidic communication with the transversely oriented distal opening of the lower stem member via the axial bore of the upper stem member;
a hub surrounding at least a portion of the tripartite stem, the hub including a retaining shelf supported by the upper stem shoulder; and
a resilient member disposed between the cap of the tripartite stem and the retaining shelf of the hub, wherein the resilient member is configured to bias the hub against the upper stem shoulder;
wherein a first seal is seated in the upper stem seal seat, a second seal is seated proximal the lower stem shoulder, a third seal is seated in the proximal seal seat, and a fourth seal is seated in the distal seal seat, the transversely oriented distal opening between the second seal and the third seal;
said endoscope having an insufflation mode and an irrigation mode, the endoscope including a valve assembly receiving seat, an interior wall portion, a gas outlet disposed between the first seal and the second seal, including a separate liquid outlet disposed between the third seal and the fourth seal;
wherein the second seal is configured to yield inwardly to a reduced diameter on application of pressure to permit air to flow about the second seal and escape in a direction toward the first seal when said endoscope is in the insufflation mode, said second seal configured to abut the interior wall portion of the endoscope to thereby inhibit air flow towards the first seal when said endoscope is in the irrigation mode.
2 . The air-water endoscope valve assembly of claim 1 , wherein the hub includes at least one distal resilient portion having a retaining boss configured for coupling to an endoscope.
3 . The air-water endoscope valve assembly of claim 1 , wherein at least one of the first seal, the second seal, the third seal, and the fourth seal is overmolded onto the tripartite stem.
4 . The air-water endoscope valve assembly of claim 1 , wherein the cap is coupled to the upper stem member via a snap fit connection.