Abstract: In the preferred embodiment of the present invention, a television camera is oriented with respect to a conveyor belt such that the direction of the scanning lines of the television camera are perpendicular to the direction of motion of the conveyor belt. Material containing foreign bodies is introduced on the conveyor belt and passes under the television camera and a light source. The television camera detects the reflected and/or radiant light and produces a video signal in accordance therewith. The image component of the video signal for each of the scanning lines is divided into signal portions. Like signal portions of respective scanning lines are successively integrated in an integration circuit to provide a non-zero signal when a foreign body is detected by the television camera. The output of the integration circuit is applied to a threshold switch, which produces a logical one when the value of the output of the integration circuit is equal to or exceeds an adjustable reference value.

Abstract: Particles of a continuous tobacco stream are intimately contacted with and thus conditioned by finely distributed solid or fluid additives in a rotary drum into which the additives are supplied by one or more spray nozzles. Tobacco particles are propelled into the drum by a rotary winnower or by an impeller nozzle which discharges a current of compressed air. The flight spans of tobacco particles can be varied by changing the speed of the winnower or by changing the pressure of air which issues from the impeller nozzle. The weight of tobacco which is being fed to the winnower or impeller nozzle per unit of time is measured, and the results of such measurements are used to regulate the flight spans of propelled tobacco particles and the quantity of additives which are admitted into the drum per unit of time.