CURRENT VELOCITY DETECTION METHOD AND CURRENT VELOCITY DETECTOR EMPLOYING HEAT SIGNAL

摘要

A current velocity detection method employing a heat signal by which an accurate measurement of a current velocity is ensured by eliminating the cause of a measurement error. In the current velocity detection method employing a heat signal where a heat signal of temperature variation is written on medium moving through a channel (1) and detected by a heat signal detection means provided remotely from the writing position in order to measure the moving velocity of the medium, first temperature sensor (20A) and second temperature sensor (20B) of the heat signal detection means are arranged at a predetermined interval (L) downstream the writing position, and the moving velocity is calculated from the difference in heat signal detection time between these two temperature sensors (20A, 20B) and the interval (L).