MICRO GAS FLOW METRE WITH PRESET SENSITIVITY Russian patent published in 2009 - IPC G01F1/69 G01F1/698 

FIELD: instrument making.

SUBSTANCE: proposed flow metre comprises the components that follow, i.e. tight casing 1 with heat exchanger 2 and gas distribution chamber 3. The latter is tightly connected with identical measurement 4 and thermal-compensation 5 channels to accommodate identical indirect-heating thermistors 6, 7. The latter make the control components of circuits 8 and 11, i.e. measuring thermistor thermal conditions stabilisation and heat carrier thermal conditions stabilisation circuits, respectively. Load resistor R_load is connected in series with the spiral of measuring thermistor 6. Voltage drop at aforesaid resistor, triggered off by indirect heating current, makes the flow metre output signal.

EFFECT: higher accuracy of measurement, preset sensitivity irrespective of gas type under control.

1 dwg