Method of determining setting values for a preliminary draft in a regulated draw frame

Abstract

A method of determining an optimal preliminary draft of sliver running consecutively through a preliminary drafting field and a principal drafting field. The method includes the following steps: setting various levels for the preliminary draft; measuring quality-characterizing magnitudes of the sliver drafted at the various preliminary draft levels; deriving sliver number deviations from the quality-characterizing magnitudes; determining a function between the sliver number deviations and the respective preliminary draft levels; forming two approximated straight lines from the function; determining a value of a point of intersection between the two straight lines; and utilizing the value of the point of intersection for setting the optimal preliminary draft.

Dependencies are inferred from the claim text.