Abstract: A pneumatic conveyor draws particles of tobacco from a vibrating trough by causing an air stream to flow from its intake end, which is adjacent to the trough, to its intake end which is connected to a suction generating device. A cyclone separator is installed in the conveyor to segregate the particulate material from the air stream and to discharge such material into a duct which feeds the material by gravity to an intermittently operated cell wheel evacuator. The latter drops batches of particulate material into the magazine of the distributor in a cigarette rod making machine. The conveyor has an elongated diffusor which is disposed upstream of the cyclone separator to decelerate the air stream, and such diffusor is followed by an arcuate portion whose radius of curvature is greater than the radius of the cylindrical wall surrounding the chamber of the cyclone separator.

Abstract: Apparatus for making filter plugs wherein the extent to which the tow is stretched or the rate of transport of a uniformly stretched tow to the wrapping mechanism is controlled by a testing unit which determines the resistance of filter plugs to axial flow of air therethrough. Alternatively, the speed of the garniture belt in the wrapping mechanism is regulated as a function of changes in resistance to flow of testing air transversely across successive increments of a uniformly stretched tow.