Adjustable open-split interface for a gas chromatograph and a mass spectrometer

Analytical apparatus comprising:

• at least one gas chromatograph;
• a detecting device;
• and
• an interface including a junction means connecting said gas chromatograph to said detecting device;
• said junction means comprising:
• a conduit having a first end and a second end;
• at least one inlet at said first end connected to said at least one chromatograph for receiving a chromatograph effluent;
• a supply means connected to said junction means through a port located at said second end for introducing an inert auxiliary fluid within said junction means to form a mixture comprising said effluent, said inert fluid or a combination thereof;
• an exhaust port located between said first and second ends and connected to an aperture means for controlling fluid pressure within said junction means;
• a bellows affixed to said conduit at said second end;
• an actuating lever having a driven end connected to said bellows and a driver end connected to a driver means for providing a reciprocal motion to at least one transfer member by actuation of said bellows by said driver means;
• said at least one transfer member including an outlet portion, perpendicular to said conduit, said outlet portion being connected to said detecting device for conveying said mixture to said detecting device, said transfer member being disposed partially within and having an inlet portion parallel to said conduit and being selectively positionable between a first position and a second position such that when said transfer member is in said first position said mixture is directed to said exhaust port and when said transfer member is in said second position said mixture is directed to said outlet;
• and
• said driver means directing said transfer member to said first position or to said second position.