Centerless grinding apparatus and work grinding condition monitoring method

A work grinding condition monitoring method for monitoring a grinding condition of a work in centerless grinding apparatus that includes:

• a grinding wheel;
• a regulating wheel;
• a blade disposed between the grinding wheel and the regulating wheel;
• a work rest which supports the blade;
• a stress sensor disposed on the work rest;
• a first drive mechanism which drives the regulating wheel in at least a horizontal direction;
• a second drive mechanism which drives the grinding wheel in at least the horizontal direction;
• and a controller which controls operations of each of the first drive mechanism and the second drive mechanism, wherein a work is supported by the grinding wheel, the regulating wheel and the blade, and the grinding wheel and the regulating wheel are rotated thereby to grind the work,
• a pair of stress sensors acting as the stress sensor each being disposed at different places in the blade or the work rest in a longitudinal direction of the blade, the work grinding condition monitoring method comprising:
• a load measurement step of measuring a load acting on the blade based on outputs of each of the pair of stress sensors and according to correlation information indicating a correlation between the load acting on the blade and the outputs of each of the pair of stress sensors;
• a frequency analysis step of determining whether a component of a designated frequency, which is extracted by performing a frequency analysis of a time series of the load measured by the load measurement step, exceeds a threshold value;
• and
• a designation processing step of carrying out designation processing for setting the component of the designated frequency to the threshold value or less in a case where it is determined in the frequency analysis step that the component of the designated frequency exceeds the threshold value.