Electromagnetic field perturbation sensor and methods for measuring water content in sheetmaking systems

摘要

A system and method of producing a paper product from a wetstock solution using a sensor for sensing resistive impedance changes of the wetstock on the support web of the system. The resistive impedance changes are used to measure physical characteristics such as water weight of the wetstock on the support web of a sheetmaking system. The system includes a fixed impedance element coupled in series with a sensor portion between an input signal and ground. The sensor portion is an electrode configuration which includes at least two electrodes with a portion of the wetstock residing between and in close proximity to the electrodes. The sensor exhibits a variable impedance resulting from changes in the physical characteristics of the wetstock. The fixed impedance element and the variable impedance of the sensor portion form a voltage divider network such that changes in impedance of the sensor portion results in changes in voltage which are measured, converted to impedance changes of the wetstock, and which are then related to water weight of the wetstock.