Improved automatic mechanical hysteresis correctors for pressure gauges influenced by the characteristics of a medium or adapted to measure these characteristics

摘要

472,565. Pressure-gauges. ETABLISSEMENTS E. JAEGER. Aug. 14, 1936, No. 22481. Convention date, April 14. [Class 106 (ii)] An automatic mechanical hysteresis corrector for diaphragm and Bourdon gauges comprises the combination with at least one body deformable under the pressure of a medium of at least one enclosure having deformable walls included in the movement transmitting mechanism and in which is stored a fluid, this enclosure communicating, by a pipe having a predetermined calibrated outflow section, with a reservoir which may be the atmosphere. In the altimeter shown in Fig. 1, the main box 1 is connected to a support 2 and communicates its movements to a needle 4 by a gearing up system 5. The correcting box 6 with outflow opening 7 is interposed between the main box 1 and the gearing. As the instrument installed'on a plane rises, the box 6 is distorted under the air it contains, but the air escapes at such a rate that compensation is effected for hysteresis lag in the main box. Several forms are described in which the compensating box is mounted below, or immediately on the top of the main box having a common wall therewith, or in one link of the transmission mechanism. In another form for a pressure gauge, the pressure is admitted to the interior of the box and the movement of the common wall affects the pressure in the compensating box. In the form shown in Fig. 6, the compensator is formed by a rigid bowl 10 to the top of which is secured a diaphragm 11 carrying a fork 12, the leakage taking place through a flattened tube 7. Abutments 15, 16 limit movement of the diaphragm in each direction. In Fig. 8, a tube 1K and a compensating tube 6K having a leak 7 are shown. Instead of the tube 6K, a capsule with a leak may be fitted. A tube with a leak may be fitted in the transmission mechanism from an aneroid box. The box may be filled with a liquid other than air when the compensating box will open into a tank containing a reserve of the fluid.