Pressure gauge for indicating small pressure changes

摘要

A pressure gauge for indicating small pressure changes includes a sac of thin flexible film material communicable with and inflatable by the pressure to be indicated, during use. The sac is supported by a base so that the sac effectively inflates in a generally vertical direction, during use. A transmission plate is pivotally mounted to the base and bears against the sac under the influence of its own weight. A pointer is directly connected to the transmission plate to indicate the position thereof under the influence of pressure in the sac to effect the indication of that pressure.