Method for e.g. determining degree of wear i.e. blunting, of rotary blade in field chopper in agricultural field, involves determining reduction of width of blade back side and distance from blade to counter blade from parameters of curve

摘要

The method involves transmitting sensor values to an evaluation unit during transit of a blade through a measuring field (4) of an analog inductive sensor (3). Signals e.g. voltage signal and current signal, of the inductive sensor are converted into a curve i.e. u-shaped voltage-time-curve. Reduction of width of blade back side and distance from a blade (11) to a counter blade (2) are determined from two characterizing parameters e.g. sensor voltage, of the curve. Sharpness of the blade is determined from the characterizing parameters of transit time and change of minimum voltage. An independent claim is also included for a device for determining degree of wear of a rotary blade and/or change of distance from the blade to a counter blade of a straw cutter.