METHOD AND INSTRUMENT FOR MEASURING FLUID VELOCITY

摘要

PURPOSE:To increase the strength of a sensor constituted of a small piece of a single crystal body consisting of germanium and to improve the measuring accuracy thereof by impressing a voltage to the sensor, maintaining a constant temp. and detecting the temp. change as a result of contact with fluid to be measured. CONSTITUTION:The sensor 1 made into a rectangular parallelepiped shape consisting of a single crystal body of germanium is fixed to a bar-shaped support 2 formed of an inorg. material such as ceramics or glass having an electric insulating characteristic and excellent heat insulating characteristic by means of an adhesive agent layer 3 at one end in the longitudinal direction of the sensor 1. An insulating layer 4 consisting of silicon dioxide, etc. is provided to one side face on the long side of the sensor 1 except one end thereof. A metal having small electric resistance is deposited by evaporation over the entire part on the side face having the layer 4 to constitute a lead wire 5A. A lead wire 5B is fixed to the other side face of the sensor 1. A voltage is impressed to the sensor 1 to maintain the sensor at the constant temp. The fluid flow rate is measured from the change in the resistance.