Page 123 - Mechanical Engineers' Handbook (Volume 2)
P. 123
112 Bridge Transducers
capacitive or inductive elements. While resistance bridge-type transducers typically possess
resonant frequencies in the tens or hundreds of kilohertz range, ac impedance bridge trans-
ducers typically possess resonant frequencies of less than 10 kHz. The larger physical size
of ac impedance bridge transducers makes them environmentally more fragile but improves
their performance by increasing their sensitivity to low-level measurands.
8.1 Inductive Bridges
Figure 34 shows an example of how variable-reluctance sensing elements can be incorporated
into an ac bridge transducer. A differential pressure transducer containing a magnetically
permeable stainless steel diaphragm as the mechanical flexure is portrayed. This diaphragm
Figure 34 Variable reluctance sensing in a bridge transducer. (Courtesy of Validyne Engineering Cor-
poration.)
