Abstract:
A controller for use in a system employing selective permeable membrane technology to maintain a controlled atmosphere within a refrigerated container. The controller is electrically interfaced to an oxygen and carbon dioxide sensing device which is disposed within the container and capable of withstanding severe enviromental conditions to measure the levels of oxygen and carbon dioxide within the container. The controller maintains present levels of oxygen and carbon dioxide within the container and is adapted to calibrate the carbon dioxide and oxygen sensing devices as well as check for proper operation of the sensing devices and default to safety conditions when a failure is detected. The controller is further adapted to control the atmosphere maintenance system in a manner adapted not to increase the peak power requirements of the system.
Abstract:
A device for maintaining a controlled atmosphere within a sealed container. The device is utilized to control the oxygen and the carbon dioxide levels within the container and utilizes permeable membrane technology to control such levels. An oilless compressor is used in conjunction with the device so as to not subject the permeable membranes to the derogatory effects associated with the presence of oil within an airstream that circulates through the permeable membranes. Additionally, the compressor is preferably mounted within the sealed container so as to not subject the compressor to the effects of temperature variation and corrosive marine environments. The present device further includes an air sampling system which is used to periodically measure the oxygen and carbon dioxide levels within the container. Control logic is included with the system which is operable to adjust the oxygen and carbon dioxide levels in accordance with the particular readings obtained by the sampling system.
Abstract:
A modular multi-channel automated medical analyzer device is disclosed, characterized by use of an ion selective electrode and/or enzymatic electrode/wash cell system which permits rapid analysis of various substances of interest contained within undiluted body fluids such as whole blood, serum and/or plasma. The ion selective electrode and/or the enzymatic electrode are disposed upon a probe which automatically axially reciprocates downwardly in a simple manipulative motion between an open-ended reference wash cell and a sample cup bearing the body fluid specimen to be analyzed. The wash cell includes an inlet port and one or more outlet ports through which is circulated an aqueous solution bearing a known concentration of the substance to be measured to provide a reference calibration medium as well as a probe washing medium. The probe is lowered directly into the sample cup to physically contact the specimen to be measured and, after analysis, is lifted upwardly into the wash cell wherein any attendant portion of the specimen remaining on the probe is stripped off by suction and the aqueous solution flow through the wash cell is initiated to thoroughly wash the probe and establish a new calibration medium for subsequent specimen analysis. The wash cell/probe assembly is specifically designed to prevent any leakage or drooling of the aqueous solution from the wash cell into the sample cup throughout manipulation of the probe. Operation of each of the modules of the analyzer is facilitated through common processing and control electronics and test measurements are accomplished initially on a dual point calibration procedure and subsequently on a single point calibration procedure.
Abstract:
An improved enzymatic electrode and electrode module specifically adapted for use in a medical analyzer device is disclosed which permits rapid analysis of substances of interest contained within undiluted body fluids such as whole blood, serum and/or plasma. The enzymatic electrode is in fluid communication with an axially reciprocating probe which selectively transports either a quantity of a buffer aqueous solution or a calibrant aqueous solution presented at a wash cell or a body fluid specimen disposed within a sample cup to an active enzyme bearing membrane positioned adjacent the enzymatic electrode. The membrane comprises a composite membrane structure having a protective membrane layer adapted to prevent the passage of blood cells and other particulate or cellular substances therethrough as well as adjust the diffusion rate of the substance of interest desired to be measured into the membrane, an active enzyme layer adapted to convert the desired substance of interest to be measured into a detectable substance and a limiting membrane formed to prevent the passage of interfering low molecular weight substance therethrough. The membrane/reagent chemistry kinetics of the enzymatic electrode are specifically defined to enable a novel pseudo-rate/created peak measurement technique to be utilized which reduces measurement inaccuracies as well as signal data processing requirements. The membrane/electrode support structure and membrane/electrode solution flow path are specifically formed to permit rapid replacement of the composite membrane and aqueous solutions by non-professional personnel.
Abstract:
A water separator adapted for use in a gas monitor includes a gas inlet port, a gas outlet port, a two-stage gas/water separator section, and a fluid reservoir. The two-stage gas/water separator section includes a first portion defining a first chamber which communicates with the gas inlet and gas outlet ports via a connecting conduit, a second portion defining a second chamber which communicates with the first chamber and the fluid reservoir, and an intermediate portion interposed between the first and second portions and defining a constricted passage between the first and second chambers. The second chamber has a frusto-conical shape in longitudinal cross section.
Abstract:
The present invention relates to an assembly and method for introducing and transporting sample containers in a chemical analyzer, and in particular, to an assembly for organizing randomly loaded sample containers in a positively-identifiable fashion. The assembly additionally includes a means for sequencing the organization of sample containers and a novel means for dispensing measured amounts of sample therefrom.
Abstract:
The percentage gas concentration within a sample as measured in a conventional optical bench is derived from the composite signal of the reference beam and sample beam transmitted through a sample cell in the optical bench. The primary source, which generates the reference beam and the secondary source which generates the sample beam are driven ninety degrees out of phase. The composite signal derived from the detector in the optical bench is digitized and then integrated according to the quadrature of the primary component of the composite signal derived from the reference beam, and is also integrated according to the quadrature of the secondary component of the composite signal derived from the sample beam. What is obtained is the integral of the absolute value of the secondary component and the integral of the absolute value of the primary component of the composite signal over one cycle of the reference beam and sample beam. The ratio of these component signals is computed to obtain a signal which is related to the percentage concentration of reference gas contained within the sample.
Abstract:
A container for holding a small quantity of liquid. The container comprises an elongated housing having a fluid receptacle disposed in the upper end thereof. The dimensions of the receptacle are substantially less than the overall dimensions of the housing, thereby facilitating the handling of the container and inhibiting evaporation of the liquid therein.
Abstract:
A moisture sensor detects the presence of foreign matter in a fluid conducting conduit and produces an electrical signal which activates a pump to purge the conduit of the foreign matter. The moisture sensor includes a pair of conduits that may be formed of an electrically conductive material and a coupling for placing the pair of conduits in fluid communication. A pair of electrodes are mounted in the coupling and are insulated from one another until electrically conductive foreign matter bridges a gap between the electrodes. Bridging the gap between the electrodes causes a signal to be sent to a source of gas that injects gas in the conduits to remove the foreign material therefrom.