| 摘要 |
An ionization detector unit innovatively adapted to provide mobility to the unit and to render it especially suitable for convenient "field-use" in point-source sampling and monitoring of the compositional characteristics of a gaseous medium such as, for example, the ambient atmosphere, and in emitting a discernible electrical signal which in response to a perceptible change in the compositional characteristics in the medium being monitored by the detector will be altered sufficiently to activate, or trigger, a suitable alarm or warning mechanism. The detector unit includes an ionization sensor cell for emitting an output signal and is powered by a suitable electrical source such as, for example, a miniature power source, and means for delivering or feeding to the sensor cell a representative stream or flow of the gaseous medium to be ionization monitored, and features a method and means for effectively compensating for variations and/or fluctuations in the electrical output signal emitted by the sensor cell as a consequent result of variations and/or fluctuations occurring in the rate of flow of the medium being delivered to and monitored thereby. The featured means is in the form of a low-voltage, battery-operated, bias device having a selectively predetermined, optimum, electrical resistance and a diode controlled voltage output operationally interconnected between one terminal or electrode of the sensor cell and an electrical ground. An innovative process and apparatus also are disclosed for determining the most effective bias voltage and preselected resistance to be provided by the biasing means.
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