Abstract: The moving parts of a tobacco cutting machine and the conveyor or conveyors which transfer tobacco to the cutting machine are driven by a variable speed motor whose speed is regulated in dependency on the volume of tobacco in a duct from which the conveyor or conveyors draw or receive tobacco for transfer into the machine. The height of the pile of tobacco in the duct is monitored by photoelectric cells which transmit signals to a speed regulator for the motor so that the speed of the motor increases and decreases when the height of the pile respectively increases and decreases. The duct receives tobacco from a magazine. Fluctuations of the height of tobacco pile in the duct are due to variations in the rate of tobacco feed from the magazine and/or to changes in size, moisture content and/or temperature of tobacco which is being supplied to the duct.

Abstract: The moisture content of tobacco, particularly greenleaf tobacco, is reduced to an accurately determined value by conveying a continuous tobacco stream through three successive sections of a transporting system wherein the tobacco is contacted by air currents. In accordance with a first embodiment, a relatively hot current of air is conveyed countercurrent to the direction of tobacco transport in the first section of the transporting system; in the second section, the flow of hot air is concurrent with the direction of tobacco transport; in the third section, the tobacco is contacted by relatively cool air having a relatively high moisture content. The air which is conveyed through the third section can be withdrawn from the first section, and the temperature of air in the second section is regulated as a function of deviations of moisture content of partially or completely conditioned tobacco from a desired moisture content.

Abstract: Shredded tobacco is blended with expanded tobacco on the foraminous bottom wall of an elongated vibratory conveyor which receives overlapping streams of shredded and expanded tobacco at one end of the bottom wall in such quantities that the ratio of shredded tobacco to expanded tobacco remains constant. Blowers are provided to supply compressed hot and cool air against the underside of the bottom wall whereby streamlets of air pass through the perforations of the bottom wall and travel across the particles of tobacco in the vibratory conveyor to convert such particles into a fluidized bed of substantially constant height which advances toward the other end of the bottom wall. The speed of streamlets is reduced above the fluidized bed to prevent the ascending streamlets from entraining appreciable quantities of particles from the bed. The particles which form the fluidized bed are intimately mixed with each other before they leave the conveyor.

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.

Abstract: The moving parts of a tobacco cutting machine and the conveyor or conveyors which transfer tobacco to the cutting machine are driven by a variable speed motor whose speed is regulated in dependency on the volume of tobacco in a duct from which the conveyor or conveyors draw or receive tobacco for transfer into the machine. The height of the pile of tobacco in the duct is monitored by photoelectric cells which transmit signals to a speed regulator for the motor so that the speed of the motor increases and decreases when the height of the pile respectively increases and decreases. The duct receives tobacco at a constant rate from a metering unit. Fluctuations of the height of tobacco pile in the duct are due to changes in size, moisture content and/or temperature of tobacco which is being supplied by the metering unit. The latter can supply tobacco to the ducts of two or more discrete cutting machines and then includes a distributor which feeds tobacco to all ducts at an equal rate.

Abstract: Tobacco particles, particularly Burley tobacco, which form a continuous stream are conditioned during transport by a series of vibratory conveyors. The foremost conveyor receives tobacco particles from a unit which contacts the particles with an atomized liquid, especially casing, and the conveyors thereupon transport the particles seriatim through preconditioning, heating, cooling and moisturizing units. The preconditioning unit has a housing consisting of one or more coiled steam pipes having orifices which discharge currents of steam against the underside of the tobacco stream at a pressure which suffices to enable the currents to form a cushion for the moving tobacco particles. The currents condense on contact with the relatively cool tobacco particles whereby the particles entrain the condensate into the heating unit wherein the particles are relieved of nitrogen and the casing is caused to penetrate into the fibrous structure of each particle with attendant roasting of the casing.

Abstract: Moist tobacco is conveyed through a rotating drum which is heated by steam circulating coils and wherein a current of hot air is caused to flow counter to the direction of tobacco transport. The moisture content of conditioned tobacco is monitored by a detector which produces a first signal when the monitored moisture content deviates from a desired moisture content. The first signal is used to rapidly change the temperature of the air current from a standard temperature by adjusting the position of a valve which mixes hot air with cooler air whereby the extent of adjustment corresponds to the extent of deviation of monitored moisture content from desired moisture content. A second signal whose intensity is indicative of the extent of valve adjustment is transmitted to the input of a proportional-plus-integral amplifier which immediately changes the steam pressure in the coils and additionally changes the steam pressure while the temperature of the hot air current deviates from the standard temperature.

Abstract: Particles of a tobacco stream are first expanded by passing through a liquid bath with attendant increase in volume. The thus expanded particles of the tobacco are thereupon conveyed through a drying zone wherein the particles are externally heated by hot air for a short period of time to thus effect rapid drying of strata immediately adjacent to external surfaces of the particles and to thereby stabilize the particles against shrinkage. In the last step, the tobacco stream is forcibly cooled with air to effect a condensation of vaporized moisture in the capillaries.

Abstract: The particles of a continuous tobacco stream are conditioned during transport through a vibratory conveyor having a bottom wall located above a stationary chamber which receives conditioned air from one or more blowers. The bottom wall is formed with apertures through which the air passes across the tobacco stream in the form of pulsating currents which agitate the particles of the stream to insure a pronounced energy exchange between tobacco particles and air. The currents pulsate due to vibration of the bottom wall relative to the chamber, and the latter is provided with transversely extending baffles which insure that the tobacco stream is traversed by air currents having different intensities. The same result can be achieved by forming the bottom wall with larger and smaller apertures.

Abstract: Particles of a tobacco stream are first expanded by passing across a high-frequency field wherein they are exposed to the action of electromagnetic waves which effect a vaporization of moisture in the capillaries with attendant increase in volume. The thus expanded particles of the tobacco are thereupon conveyed through a drying zone wherein the particles are externally heated by hot air for a short period of time to thus effect rapid drying of strata immediately adjacent to external surfaces of the particles and to thereby stabilize the particles against shrinkage. In the last step, the tobacco stream is forcibly cooled with air to effect a condensation of vaporized moisture in the capillaries. The expansion of tobacco can be enhanced if the tobacco stream is caused to pass through a bath containing freon or another organic fluid having a boiling point lower than water before the tobacco stream is conveyed across the high frequency field.

Abstract: The arrangement determines the moisture content of tobacco, in either leaf- or comminuted form, tobacco substitutes, other smokers' products, filter materials, cigarette and cigar papers and wrappings, related and analogous fibrous and other materials, and the like. The material in question is supported by a supporting arrangement. First and second electrodes are connected to an A.C. voltage source to form a capacitor. The electrodes are so disposed that the electric field joining the electrodes travels through the material being supported. The moisture of the material is determined by determining the effect upon the capacitor of the moisture in the material being supported and penetrated by the electric field. An arrangement is provided for compressing the material in question while the material is actually being supported and penetrated by the electric field.

Abstract: The moisture content of a stream of tobacco leaves is increased during travel through a rotary drum wherein the leaves are contacted by and exchange heat and moisture with a current of hot humid air which flows concurrent with the leaves. The moisture content of air is regulated in dependency on deviations of the final moisture content of tobacco leaves from a desired final moisture content by varying the temperature of a shower of water droplets across which the air current passes on its way into the inlet end of the drum. The temperature of air is normally constant but is changed when the initial moisture content of tobacco leaves exceeds the desired final moisture content.