Patent ID: 7309036

Claim:
A control system for a refiner, the refiner comprising a housing having a chamber, a support in said chamber, a material-admitting inlet and an outlet; a nonrotating refining member mounted on said support, and a rotary refining member disposed in said chamber adjacent said non-rotating refining member and defining there between a path for the movement of material from said inlet to said outlet, said rotary refining member and said non-rotating refining member being coaxial with each other, the control system comprising a sensor mounted in direct mechanical connection to the non-rotating refining member so that said sensor is responsive to axial vibration movement of said support, an analog to digital converter directly connected without filtering without filtering to the output of said sensor, and a controller connected to said analog to digital converter and responsive to said analog to digital converter to compare the amplitude of the output signal from the sensor to a baseline value based on the level of vibration associated with the pulp refiner when it is operating without plate clashing, and when the signal exceeds the baseline value, take an action intended to help alleviate the plate clashing.