| 摘要 |
<p>A flueric partial pressure sensor includes a flueric bridge having two bridge legs (12, 13) adapted for sensing a reference-gas and sample-gas mixture. A linear resistor (24, 23) and an orifice resistor (26, 25) are incorporated in each of the bridge legs (12,13) which are conjoined to discharge from a single outlet. The resistors (24,23,26,25) are arranged to provide an asymmetric balance of the flow rates through the bridge legs (12,13). The asymmetric balance is selected so that in operation a constant pressure output signal is generated for a chosen partial pressure of a constituent gas of the sample-gas mixture in varying absolute pressure conditions such as changes in altitude.</p><p>Respective pressure signal outlets (22,21) connected one with each bridge leg (12, 13) at a position between the linear resistor (24, 23) and the orifice resistor (26, 25), are used to effect control of a flueric laminar flow proportional amplifier (11). Outputs from the flueric amplifier (11) may be used to regulate a fluid mixing valve (51) shown in Figure 3, or to effect switching of an indicator device (81 shown in Figure 4.</p> |
