Thermal flow sensor e.g. for air intake of vehicle IC engine - has thermal resistance with heat generating section, non-heat generating section and insulating base part

摘要

The flow sensor includes a thermal resistance with a heat generating section formed on an insulating base part. The ratio of the area of the heat generating section to the total area of the resistance in contact with the measurement fluid, including the heat generating section, is in the range from 0.65 to 0.85. The thermal resistance has a heat generating section (A), a section (B) which generates no heat and a base section (C) carried by a supporting part (S). The heat generating section and the section which generates no heat are arranged in the measurement fluid. ADVANTAGE - Improved response to change in flow speed of measurement fluid.