PROCESSES FOR DETECTING PERIODIC DEVIATIONS OF TEXTILE THREAD SENSING SIGNALS

摘要

The method is used for determining periodic fluctuations of the transverse dimension of a running yarn, particularly on open-end spinning machines for detecting the moiré effect. The electrical scanning signal (F') is transformed into a sequence of needle pulses (S') this pulse sequence (S') is compared with a reference pulse sequence (Z') of a particular preselected period (p). The mutual phase relationship of the pulse sequences (S' and Z') is changed in small steps, the number of coincidences of pulses within a number of such steps assuming either a maximum or not indicating any pronounced maximum. Two criteria for determining a maximum are specified. The first criterion is met when the number for T exceeds a particular minimum value the second criterion applies when the sum of such excessive T values in successive test steps is greater than a further minimum value.