Key technique for Inner Hole Diameter Measure with Capacitive Probe

摘要

The capacitive probe for inner hole diameter measuring was introduced, the equipotential guard ring technique was adopted to eliminate edge effect of capacitive probe effective measuring electrode, the driving cables technique was used to reduce the influence of parasitic capacitance, and then we realize the precision measurement in any section of inner holes for diameter from Φ1.85 mm to Φ7 mm.