Auto leveler

Abstract

An apparatus for maintaining sliver thickness uniform whereby the web from a carding machine is gathered by a trumpet and passed between a grooved driven roller and a sensor roller riding in the groove so that the movements of the sensor roller vary as a function of sliver density. The sensor roller is mechanically connected to a magnetic core so that movement of the sensor roller varies the coupling between a primary transformer winding and a pair of secondary windings. The voltages induced in the secondary windings are applied, after a delay, to a first differential amplifier whose output in turn is connected to a second differential amplifier which is periodically rendered operative by a pulse generator and to which is also connected a potentiometer for adjusting desired density. The output of the second amplifier is connected to a pair of relay coils, one responsive to positive excursions and the other to negative. Each relay controls a switch connecting a power source to a motor coil for rotating the motor which in turn controls a variable speed drive for controlling, for example, the feed roll of a conventional card.

Dependencies are inferred from the claim text.