A tilting micromanometer with continuous sensitivity control

A null-reading liquid manometer is described in which the meniscus is returned to the reading position by varying the angle of slope. Sensitivity automatically decreases as the applied pressure increases; it is highest at zero readings and its absolute level can be continuously varied. A magnification factor can be employed by using different reading positions on the tube which is 0.1 in. bore, pivoted near the reservoir and tilted at its distal end by a standard micrometer-head, so keeping the construction simple and not critical. The prototype, which is wall-mounted, reads easily at air-speeds of 7.5 ft/s with a Pitot-static tube; the highest limits of accuracy assessed are ± 0.2 dyn/cm2, i.e. 6.5 ft/s ± 0.5%. The upper reading limit is about 0.7 in. w.g. (50 ft/s). RESP-3445