PITOT CALIBRATED AIR VELOCITY MEASURING SYSTEM WITH TRANSDUCER

摘要

An air velocity measuring system having a probe adapted to be placed into a flow of air and coupled to a measuring apparatus. The measuring apparatus may be a flow meter having a moving vane which is responsive to the air passing through the probe or it may be an electrical transducer adapted to be responsive to a flow of air through the probe. In the preferred embodiment of the invention a range adjusting switch is coupled between the probe and the measuring apparatus and enables the system to have a plurality of ranges by placing a resistance, in the form of one of a plurality of needle valves, into the path of the air flow to the measuring apparatus. The probe is a conduit having means for adjusting the quantity of air flowing to the measuring apparatus. In the preferred embodiment, the probe, the range adjusting switch, and the measuring apparatus are calibrated as a system. Once calibrated, the individual elements of the system are interchangeable with the corresponding elements of another of similarly calibrated mass produced systems without requiring subsequent recalibration of each system. The means for adjusting the quantity of air flowing to the measuring device are adjustable during the calibration of the probes individually or as part of the air velocity measuring system.