Abstract: The present invention relates to a sample filtration device of the type employing differential pressure. An outer container filled with a sample to be filtered slidably receives a hollow plunger having filter media disposed near one end and sealing means disposed in an annular groove about the periphery of the plunger. The annular groove of the plunger is formed by two components: an annular shoulder on a collector portion and the axial face of an annular ring formed in a retainer portion. The two portions are frictionally engaged to retain the filter in place and form the annular groove for the sealing means. This construction permits straight-pull molding of the component parts which eliminates mold mismatch flaws.

Abstract: The present invention relates to a sample filtration device of the type employing differential pressure. An outer container filled with a sample to be filtered slidably receives a hollow plunger having filter media disposed near one end and sealing means disposed in an annular groove about the periphery of the plunger. The annular groove of the plunger is formed by two components: an annular shoulder on a collector portion and the axial face of an annular ring formed in a retainer portion. The two portions are frictionally engaged to retain the filter in place and form the annular groove for the sealing means. This construction permits straight-pull molding of the component parts which eliminates mold mismatch flaws.

Abstract: Apparatus and method for analyzing a biological material such as blood serum to determine whether a substance indicative of disease is present. The apparatus utilizes a two-way valve construction for rinsing a cartridge containing the material under analysis at various operating stations.

Abstract: A disposable intravenous pump chamber assembly for an intravenous administration set which substantially reduces the problem of air bubble entrapment so that the amount of intravenous fluid delivered is effected in an accurate manner. The pump chamber assembly is specifically constructed to be utilized in conjunction with a diaphragm-type pump with external valving. The pump chamber cassette is held in the pump in a unique manner and includes a porting and fluid delivery arrangement which reduces the problem of air entrapment in the pump chamber.

Abstract: A flashback indicator which is integrally formed in a parenteral solution or blood set to serve as a patency check device. A length of clear plastic tubing having an enlarged portion is integrally connected in a parenteral fluid or blood set in such a manner that a patency check can be made without fear of the indicator becoming disconnected from the set during the supplementary administration of a drug such as by means of a hypodermic syringe. In a preferred manner, the flashback indicator is formed from bubble-like tubing wherein the wall thickness of the enlarged portion of the bubble is at least as large as that of the tubing in the set having a smaller and constant diameter.

Abstract: A high volume filter for use in an I.V. or blood administration set. A double filter unit is formed by folding a length of filter material into two portions to form pocket members with tubular inlets placed in each. These components are then sealed into a length of plastic tubing with an additional tubular member to form a filter unit. In a preferred embodiment, the filter unit is formed integrally with a drip chamber.

Abstract: A rotatable connecting device which provides for quick and positive interfitment between a venipuncture unit and an intravenous administration set without rotation or twisting of the venipuncture unit or intravenous tubing. A rotatable collar is provided on one of the members constituting the connecting device and is captively held thereon while permitting longitudinal movement. Frictional engaging means are disposed on the body member retaining the collar as well as the collar to provide an interference fitment. Internal threads are defined in the rotatable collar for engagement with a flange member disposed on the catheter hub. A luer lock fitment is afforded between the catheter member and the member carrying the rotatable collar.

Abstract: A screw top closure for a container opening defining a helically threaded neck, and a rotatable screw top positioned to permit rotation by the screw top between outward and inward positions on the neck. A sealing partition is positioned across the opening of the neck. In accordance with this invention, an aperture is defined in the sealing partition, the aperture being positioned in off-center relation to the rotational axis of the screw top. A sealing cap member is positioned across the aperture, with a rupturable seal, facing the screw top. A projection is defined on the side of the screw top facing the partition, being positioned to be longitudinally spaced from the sealing cap member when the screw top is in the outward position, and to engage the sealing cap member when the screw top is rotationally advanced to its inward position. Accordingly, the seal between the cap member and the partition may be ruptured in aseptic manner by the projection, to open the aperture.