Abstract
The heat pulses produced by cutting grains in the grinding zone are measured by some kinds of pyrometers in order to investigate the influence of their response speed on the output. In the infrared radiation pyrometers (I. R. P.), InAs and PbS cells are used as detectors, and the heat signal is received by an optical fiber at the bottom of a small hole which extended nearly to the ground. surface. The results are as follows. Since the thermocouple formed by spot welding is inferior in res ponse speed, it cannot catch faithfully the heat pulses and its signal trace versus time is observed as a smooth curve without peaks. However, thetrace observed by InAs I. R. P. with the highest speed response has many sharp peaks, because this pyrometer can respond the rapid change of temperature. Moreover, the surface temperature estimated by extrapolation of measured values is higher in the latter. The thermocouple method devised by Peklenik can also catch the change of temperature, but it is considered to be basically impossible to respond it correctly. As an application of InAs I. R. P., the grinding temperature distribution in fine ceramic Si3N4 is measured. The peak temperature at 5 pm deep below the ground surface is about 550°C, but the surface temperature cannot be estimated because its gradient is very steep near the ground surface.
