| 摘要 |
A pump for a gas sampling or analyzing system includes a pump body having walls impervious to the gas and an electrical coil within body. The pump is coupled in series with a gas sensor and a gas volume containing the gas to be sampled or analyzed. By varying the amplitude of either AC or DC current supplied to the coil, the temperature of the coil and, hence, the temperature of the gas within the pump can be varied, causing the pump to "inhale" upon lowering the temperature of the gas within the pump and "exhale" upon raising the temperature of the gas within the pump, thereby enabling the gas from the gas volum to be drawn periodically into and expelled from the sensor for sampling. |
