| 摘要 |
<p>PURPOSE:To decrease the power consumption of a heat emission part and sense the flow speed with high sensitivity by locating the wider portion of the resistance pattern of the heat emission part a cartain distance apart from the major portion of the heat emission part. CONSTITUTION:Wider portion 4a-4d, 5a-5d, 6a-6d of each resistance pattern of a heater element, 4, an upstream sound-measuring resistance element 5, and a downstream temp. measuring resistance element 6 is located a certain distance apart from the major portion of respective element and is provided only around the boundary between a diaphragm 3a and the large wall thickness part of a semiconductor lease board. This lessens the heat amount running away to the semiconductor base board through respective resistance pattern having a thermal conductivity several times as large as the material of diaphragm 3a. which is thus given a very good heat insulation. Therefore, the power consumption lessens in the element 4 while the sensing sensitivity is enhanced in the upstream temp.-measuring resistance element 5 and downstream temp.- measuring resistance element 6, and also dislocation of zero point resulting from different thermal conductivity of gases and shift of the sensitivity relative to the rate of flow by volume are lessened.</p> |
