Automatic fluid injector, and magazine therefor

In a fluid injector, or apparatus, for withdrawing fluid specimens from septum type vials for repetitively measuring and injecting preselected quantities of fluid specimens into a medium such as an inlet to an analytical instrument, the combination comprising

• a base plate, constituting a portion of a housing, which can be mounted adjacent the inlet to the analytical instrument,
• a slide plate reciprocably, unidirectionally movable upon said base plate,
• means for reciprocation of said slide plate,
• (a) a fluid injector sub-assembly mounted upon said slide plate, inclusive of
• a syringe barrel,
• a hollow needle mounted on the end of the barrel providing an opening from the dispensing end of said needle through said barrel and needle, the needle being sealed, and slidably mounted within the end of the barrel so that the barrel is movable relative to said needle for dispensing the fluid specimen by displacement thereof through the dispensing end of the needle, the hollow needle being affixed to said slide plate,
• a valve located at the opposite end of said barrel for opening the barrel to permit ingress of a fluid specimen into said barrel and needle, and means for moving said valve and barrel upon said slide plate relative to said affixed needle on closure of said valve,
• (b) an injector feed sub-assembly mounted on said base plate, inclusive of a probe assembly characterized as one which is comprised of
• a pair of concentric hollow conduits, one of which serves as a gas supply conduit inclusive of a gas inlet and gas outlet, and the other of which serves as the fluid specimen supply conduit inclusive of a fluid specimen inlet, and a fluid specimen outlet wich is operatively connected through the valve at the rearward end of the barrel of said fluid injector sub-assembly, the outer conduit being shaped in the form of a needle with the pointed end faced downwardly to provide means for puncturing the septum of a septum type vial delivered thereto so that the supply conduits of the probe can enter into said vial, and
• means for actuation and reciprocation of said probe assembly to puncture the septum of the vial for removing a fluid specimen from said septum type vial,
• (c) a magazine sub-assembly, inclusive of
• a floor plate mounted within said housing below said base plate and probe assembly,
• a plurality of sprockets, with gear teeth, rotatably mounted upon said floor plate, the plane of rotation of said sprockets being parallel to the plane of orientation of said floor plate,
• a flexible closed loop roller chain comprised of a series of links aligned in tandem, each link of the chain including a pair of parallel aligned, spaced apart rollers equal in length and vertically oriented with respect to said floor plate, secured together by a plate mounted on each side of said pair of rollers, the openings in the chain between the rollers being meshed with and guided upon said sprockets,
• a plurality of open end vial transport containers, vertically oriented with the open ends facing upwardly, mounted upon upwardly facing plates which form the links of the roller chain, within which septum type vials filled with fluid specimens can be placed with their septum ends faced upwardly,
• a motor mounted on said base plate, the output shaft of which can be geared to at least one of said sprockets for drivings said roller chain through its closed fixed path,
• a means for stopping each of said vial transport containers in sequence at a pick-up station below, and in the path of said probe assembly for penetration of the septum of a vial by the pointed end of said probe assembly,
• whereby a pressurized fluid can be injected through the probe into a vial to pressurize the fluid specimen contained therin, the fluid specimen then transferred from the vial via the hollow probe to the barrel of said fluid injector sub-assembly for cleaning, purging and filling said fluid injector with a preselected quantity of the fluid specimen for subsequent injection into the inlet of the analytical instrument by actuation of said means for reciprocation of said slide plate on which said fluid injector sub-assembly is mounted to thrust the dispensing end of the needle into the inlet of said analytical instrument.