Abstract:
A method of and device for calibrating infrared radiation transducers. A concentration factor representing the ratio of a data signal to a reference signal for a known concentration of a designated gas in a sample containing that gas is generated. The concentration factor is stored and used during subsequent calibration procedures. The calibration device has a zero cell and a span cell with windows for transmitting infrared radiation and radiation reflecting or absorbing material in the span cell. The span cell therefore provides a known and consistent level of radiation absorption.
Abstract:
Infrared radiation emitter units for gas analyzers and other applications. The emitter has a substrate with a film of electrically resistive, emissive material on one of its surfaces. The emitter is so mounted on an emitter unit base that it can freely expand as the emitter heats up. A lead frame commutator, employed to electrically connect the emitter to an external power source, also facilitates the assembly of the unit. A component with a plated, parabolic surface collimates and focuses into an appropriate beam the energy generated by the emitter.
Abstract:
An integrated airway adapter capable of monitoring any combination of respiratory flow, O2 concentration, and concentrations of one or more of CO2, N2O, and an anesthetic agent in real time, breath by breath. Respiratory flow may be monitored with differential pressure flow meters under diverse inlet conditions through improved sensor configurations which minimize phase lag and dead space within the airway. Molecular oxygen concentration may be monitored by way of luminescence quenching techniques. Infrared absorption techniques may be used to monitor one or more of CO2, N2O, and anesthetic agents.
Abstract translation:能够监测呼吸流量O 2浓度的任何组合以及CO 2 2 N 2 N 2 N 2中的一种或多种的浓度的组合气道适配器, O和麻醉剂实时呼吸。 可以通过改进的传感器配置在不同入口条件下通过差压流量计监测呼吸流量,从而最小化气道内的相位滞后和死区。 可以通过发光淬灭技术监测分子氧浓度。 红外吸收技术可用于监测一种或多种CO 2,N 2 O和麻醉剂。
Abstract:
A transducer for nondispersive infrared radiation (NDIR) gas analysis and a passive device for verifying the calibration of the transducer. The calibration verification device can be mounted on a cable by which the transducer is attached to an associated signal processing-control-display unit (SPCDU) or monitor. Calibration parameters for the transducer are stored in a plug at the monitor end of the cable. The transducer includes an integrated subassembly of an infrared radiation source unit, an infrared radiation detector unit, and a flex connector and may be employed with an airway adapter preferably maintained by a thick film heating element at an above-dewpoint temperature to ascertain the concentration of a specie potentially present in gases flowing through the adapter. The transducer may also be employed for other purposes.
Abstract:
Apparatus or systems which employ luminescence quenching to produce an oxygen concentration indicative signal. Components of such systems include: (1) an airway adapter, sampling cell, or the like having a sensor which is excited into luminescence with the luminescence decaying in a manner reflecting the concentration of oxygen in gases flowing through the airway adapter or other flow device; (2) a transducer which has a light source for exciting a luminescable composition in the sensor into luminescence and a light sensitive detector for converting energy emitted from the luminescing composition as that composition is quenched into an electrical-signal indicative of oxygen concentration in the gases being monitored; and (3) subsystems for maintaining the sensor temperature constant and for processing the signal generated by the light sensitive detector. Sensors for systems of the character just described, methods of fabricating those sensors, and methods for installing the sensors in the flow device.
Abstract:
Apparatus or systems which employ luminescence quenching to produce an oxygen concentration indicative signal. Components of such systems include: (1) an airway adapter, sampling cell, or the like having a sensor which is excited into luminescence with the luminescence decaying in a manner reflecting the concentration of oxygen in gases flowing through the airway adapter or other flow device; (2) a transducer which has a light source for exciting a luminescable composition in the sensor into luminescence and a light sensitive detector for converting energy emitted from the luminescing composition as that composition is quenched into an electrical signal indicative of oxygen concentration in the gases being monitored; and (3) subsystems for maintaining the sensor temperature constant and for processing the signal generated by the light sensitive detector. Sensors for systems of the character just described, methods of fabricating those sensors, and methods for installing the sensors in the flow device.
Abstract:
Gas analyzer systems which include: (1) a transducer for outputting a signal indicative of the concentration of a specified gas in a sample which may contain that gas, and (2) an airway adapter or cuvette with a flow passage for confining the sample to a particular path traversing the transducer. The cuvettes feature radiant energy transmitting windows which are flush mounted in apertures on opposite sides of the cuvette flow passage and are fabricated from a polymer such as biaxially oriented polypropylene which is malleable, yet resistant to wrinkling, warping, and other forms of distortion. Retainer rings keep the windows flat and distortion free with an accurately reproducible spacing between the windows.
Abstract:
Sampling attachments or systems for infrared gas analyzers of the non-dispersive type. Major components of the system include a sampling device or cuvette, a vacuum pump for effecting a flow of the gases to be analyzed through the cuvette, a microprocessor based pump control, and a switch which is closed and allows the pump to be turned on only if an appropriate sampling cuvette is connected up to the pump. The sampling attachments are designed for medical applications--to provide readings of tidal carbon dioxide, for example. They have a minimally invasive nasal cannula for collecting the gases which are to be subjected to analysis; viz., those exhaled by a patient. These gases are conducted to the cuvette through a line which is gastight but allows moisture to escape, thereby keeping moisture mixed with the gases being analyzed from corrupting the readings outputted by the gas analyzer. The attachment can be easily and quickly disassembled and the components disposed of or sterilized and recycled if they become contaminated. Provision is made for collecting the gases after they have been discharged from the cuvette so that they will not be discharged into and perhaps contaminate the ambient surroundings.
Abstract:
Gas analyzers of the non-dispersive infrared radiation type which are designed to measure the concentration of one gas in a mixture of gases containing that gas. A novel, electrically modulated, stable, thick film infrared radiation emitter is employed to emit a beam of collimated, focused energy; and two electrically biased detectors are preferably used so that a ratioed, error eliminating output signal can be supplied to the failsafe, signal processing circuitry of the analyzer. The latter, and a conventional analog-to-digital convertor, supply information to a microcomputer which: (1) turns the infrared radiation emitter on and off; (2) controls a heater which keeps the infrared radiation detectors at a constant, precise temperature; and (3) controls displays of a variety of information concerning the gas being measured and the status of the gas analyzer. The microcomputer also accepts ambient temperature, barometric pressure, and other compensation factors. Typically, a disposable airway adapter will be included in the gas analyzer to confine the mixture of gases being analyzed to a path having a transverse dimension of precise and specific length and to provide an optical path across that stream of gases between the infrared radiation emitter and the infrared radiation detectors. The emitter and detectors are incorporated in a transducer head which can be detachably fixed to the airway adapter.