Abstract: A method for preparing a volume of blood for cellular analysis in a hematology instrument includes the step of gently mixing the blood sample with a reagent and/or diluent using a stream of air. Preferably, the air stream is directed at the liquid(s) to be mixed at a relatively steep angle, preferably less than about 10 degrees from the normal to the liquid surface. A mixing vessel adapted for use in a hematology instrument for carrying out the method of the invention comprises a cap that supports an air jet for directing the air stream at an angle in keeping with the method of the invention.

Abstract: An apparatus for analyzing a population of particles is set forth. The apparatus includes an emitter adapted to generate a beam of electromagnetic radiation, such as from a laser, and a particle chamber disposed in a path of the electromagnetic radiation beam. The apparatus also includes a sensor to detect electromagnetic radiation scattered by or otherwise received from the particle chamber. A sensor alignment unit supports the sensor along a detection axis and allows adjustment of the position of the sensor along orthogonal axes lying in a plane that is generally perpendicular to the detection axis. In one embodiment, the sensor alignment unit includes a first support platform and a first adjustment mechanism disposed to adjust the position of the first support platform along a first orthogonal axis. The sensor alignment unit also includes a second support platform that supports the sensor.

Abstract: A method and apparatus for aspirating a liquid (e.g., blood) from a container uses an electrically biased thermistor element, mounted proximate the tip of a liquid-aspirating probe, to determine that the probe is safely submerged within a body of liquid to be aspirated at all times during the aspiration process. Also disclosed are different aspiration probe assemblies that are useful in the method and apparatus of the invention.

Abstract: A method and apparatus for aspirating a liquid (e.g., blood) from a container uses an electrically biased thermistor element, mounted proximate the tip of a liquid-aspirating probe, to determine that the probe is safely submerged within a body of liquid to be aspirated at all times during the aspiration process. Also disclosed are different aspiration probe assemblies that are useful in the method and apparatus of the invention.

Abstract: A method for preparing a volume of blood for cellular analysis in a hematology instrument includes the step of gently mixing the blood sample with a reagent and/or diluent using a stream of air. Preferably, the air stream is directed at the liquid(s) to be mixed at a relatively steep angle, preferably less than about 10 degrees from the normal to the liquid surface. A mixing vessel adapted for use in a hematology instrument for carrying out the method of the invention comprises a cap that supports an air jet for directing the air stream at an angle in keeping with the method of the invention.

Abstract: A self-adjusting pick-up tube assembly for aspirating liquid from containers of varying heights. Such assembly comprises (a) a platform member adapted to be positioned in contact with the bottom of a container when the pick-up tube is being used to aspirate liquid from such container; (b) a disk-shaped member adapted to be retained in a position proximate the container's liquid filling aperture when the pick-up tube is in use; (c) a flexible conduit interconnecting respective liquid passageways in the platform and disk-shaped members, and (d) a telescopic mount for enabling relative movement between the platform and disk-shaped members to accommodate containers of different height.

Abstract: The invention provides a tube adapter for use on a plurality of different types of tubes. The tube adapter includes a sleeve in which to receive smaller diameter tubes. The sleeve preferably includes a bar code reader slot to allow reading of bar codes on the tubes through the sleeve. The sleeve includes a spring portion biased to retain tubes in the tube adapter. The sleeve also preferably includes a key for aligning the tube adapter in a tube cassette. The tube adapter can include a clip to prevent the tube adapter from inadvertently being removed, rotated or dropped from the tube cassette.

Abstract: A method for sampling, metering and delivering precise microliter volume aliquots of a liquid blood sample to mixing and testing means of an electronic blood analysis system for analysis using a sampling and metering valve assembly in which is defined plural through fluid flow paths, one of the flow paths including a loop for metering and isolating a sample aliquot therein, the method comprising the steps of defining first and second dedicated passages within the valve assembly displaced one from the other and from the loop containing the isolated aliquot, introducing an inert gas to the loop to force the aliquot therein to said first dedicated passage at the displaced location thereof, placing the first and second dedicated passages in communicating relationship and introducing lyse reagent to the second dedicated passage to force the isolated aliquot from the first dedicated passage with the lyse reagent to a location exterior of the valve assembly without contaminating any flow paths which has been travers

Abstract: A liquid metering and transfer valve assembly having the capability of metering, isolating, transfering and delivering precise microliter volume aliquots of a blood sample, from a source thereof, to mixing and testing chambers of an electronic blood analysis system for analysis, and further, carrying a loop for metering and isolating an additional sample aliquot within the valve assembly in the loop, a first dedicated passageway for introducing a first fluid to the loop to force the additional aliquot from its isolated location to a first dedicated portion of the valve assembly displaced from the loop and a second dedicated portion of the valve assembly to establish a flow path for introducing a lysing reagent to the first dedicated portion to force the additional aliquot from its displaced disposition, as a lyse reagent/aliquot mixture, to a selected additional mixing and testing chamber exterior of the valve assembly without contaminating any interior flow path traversed by a blood sample and associated dil

Abstract: For use in automated or semi-automated hematology analysis apparatus, a method of introducing a volume of blood from a source thereof along a conduit leading to a sampling, metering and transfer valve assembly of the apparatus comprising the steps of drawing a predetermined volume of blood sample from the source, causing the drawn blood sample to travel along the conduit toward the valve assembly, providing detectors adjacent the inlet and outlet of the valve assembly and using vacuum to position the drawn blood sample so that it passes through the valve assembly and is disposed in metering condition within the valve assembly, the positioning being responsive to signals provided by the detectors.