In-process measurement of topography change of grinding wheel by using hydrodynamic pressure

This paper deals with an in-process measurement method for topography change of a grinding wheel, which can apply to wet grinding. A pressure sensor is set beside a grinding wheel with a small gap. When grinding fluid is dragged into the gap, hydrodynamic pressure, which corresponds to the gap length and the topography, can be measured. This method is applied to a cylindrical grinding machine. No electromagnetic properties of a workpiece and a grinding wheel affect measured results. The pressure is decreased with the increase of the gap length when the grinding fluid is supplied in the tangential direction of the grinding wheel. Spectra of the pressure are measured with an FFT analyzer. Higher frequency components are increased with the progress of grinding because of turbulent flow. Loading and dulling of a grinding wheel can be detected by the proposed method as well as its wear.