| 摘要 |
<p>PURPOSE:To minimize fluctuation of gas flow measuring accuracy, by attaching two resistance wires, which constitute an electric heater and a thermo-electric resistance, in a stripe pattern and in such a direction that they cross one another as seen from the front side. CONSTITUTION:An electric heater 10 to be provided in a flow-measuring tube 9 is to consist of platinum resistance wire 10b attached on a ring-like print board 10a in an equal-spaced lateral stripe pattern. On the other hand, No.1 and No.2 temperature dependence resistances 11 and 12, which are located on the downstream of and in the vicinity of the electric heater 10 and on the upstream side of and apart from the electric heater 10 in the dlow measuring tube 9 are made in such a manner that platinum resistance wires are attached on ring-like print boards 11a and 12a in an equal-spaced lateral stripe pattern. By attaching the resistance lines to the electric heater 10 and also to No.1 and No.2 thermo-electric resistances 11 and 12 in such a manner that they cross one another, it becomes possible to eliminate an extremely small heat distribution from the flow-measuring tube and also to minimize fluctuation of flow measuring accuracy to such an extent as not to cause any problem to the actual operation.</p> |
