Method and apparatus for conditioning tobacco

Claim 3

A method as defined in claim 1, further comprising the steps of collecting at least a portion of the gaseous fluid of at least one of said first and second currents after said one current has contacted the particles in the respective portion of said path, utilizing the thus collected gaseous fluid to form at least a portion of said third current, and maintaining said third current in contact with the particles for an interval of time which suffices to establish a hygroscopic equilibrium between the gaseous fluid of said third current and the particles.

Claim 4

A method as defined in claim 1, wherein said transporting step comprises vibrating said particles so that the particles are transported in the form of a layer of agitated particles.

Claim 5

A method as defined in claim 1, wherein said particles form a stream of greenleaf tobacco.

Claim 6

A method as defined in claim 4, further comprising the step of compacting the conditioned tobacco.

Claim 7

A method as defined in claim 1, wherein each of said currents is heated air.

Claim 8

A method as defined in claim 6, further comprising the steps of subdividing each of said currents into a plurality of smaller currents immediately prior to contact with tobacco particles in the respective portions of said path.

Claim 9

A method as defined in claim 1, further comprising the step of gradually reducing the speed of said first and second currents during contact with tobacco particles in the respective portions of said path.

Claim 10

A method as defined in claim 1, further comprising the step of continuously measuring the temperature and/or moisture content of tobacco particles downstream of said second portion, and changing the speed, temperature and/or moisture content of at least one of said first and second currents when the measured temperature and/or moisture content of the particles deviates from a desired value.

Claim 11

A method as defined in claim 1, further comprising the steps of measuring the temperature and/or moisture content of said third current prior to entry into said third portion of said path, comparing the thus measured temperature and/or moisture content of said third current with a predetermined value, and changing the temperature and/or moisture content of said third current when the measured value thereof deviates from said predetermined value, said predetermined value being selected in such a way that the tobacco particles reach a condition of hygroscopic equilibrium with said third current not later than on leaving said third portion of said path.

Claim 12

A method as defined in claim 1, further comprising the steps of measuring the moisture content of tobacco particles between said second and third portions of said path, and adjusting the speed, temperature and/or moisture content of at least one of said first and second currents as a function of deviations of the measured moisture content of tobacco parTicles from a predetermined value.

Claim 13

In an apparatus for conditioning tobacco with a gaseous fluid to thereby change its temperation and/or moisture content, a combination comprising transporting means arranged to transport a stream of unconditioned tobacco particles along an elongated path, said transporting means comprising a plurality of successive sections defining successive portions of said path; first conditioning means arranged to subject the particles of tobacco to the action of a first current of a gaseous fluid in a first section of said transporting means and including means for conveying said first current substantially transversely of the direction of transport of tobacco particles in said first section and means for maintaining the speed, temperature and/or moisture content of said first current within a predetermined range; second conditioning means arranged to subject the particles of tobacco to the action of a second current of a gaseous fluid in a second section of said transporting means located downstream of said first section, said second conditioning means comprising means for conveying said second current substantially transversely of the direction of tobacco transport in said second section and means for maintaining the speed, temperature and/or moisture content of said second current within a predetermined range; and third conditioning means arranged to subject the particles of tobacco to the action of a third current of a gaseous fluid in a third section of said transporting means located downstream of said second section, said third conditioning means comprising means for maintaining the speed, temperature and/or moisture content of said third current within a predetermined range.

Claim 14

In an apparatus for conditioning tobacco with a gaseous fluid to thereby change its temperation and/or moisture content, a combination comprising transporting means arranged to transport a stream of unconditioned tobacco particles along an elongated path, said transporting means comprising a plurality of successive sections defining successive portions of said path; first conditioning means arranged to subject the particles of tobacco to the action of a first current of a gaseous fluid in a first section of said transporting means and including means for conveying said first current substantially transversely of the direction of transport of tobacco particles in said first section and means for maintaining the speed, temperature and/or moisture content of said first current within a predetermined range; second conditioning means arranged to subject the particles of tobacco to the action of a second current of a gaseous fluid in a second section of said transporting means located downstream of said first section, said second conditioning means comprising means for conveying said second current substantially transversely of the direction of tobacco transport in said second section and means for maintaining the speed, temperature and/or moisture content of said second current within a predetermined range; and third conditioning means arranged to subject the particles of tobacco to the action of a third current of a gaseous fluid in a third section of said transporting means located downstream of said second section, said third conditioning means comprising means for maintaining the speed, temperature and/or moisture content of said third current within a predetermined range.

Claim 15

A combination as defined in claim 12, wherein said transporting means comprises at least one vibratory conveyor having a foraminous tobacco supporting bottom wall and wherein said means for conveying said first and second currents are arranged to convey the respective currents through said bottom wall substantially at right angles to the direction of transport of tobacco particles.

Claim 16

A combination as defined in claim 13, wherein said vibratory conveyor further comprises a pair of side walls diverging upwardly and outwardly from said bottom wall, said means for conveying said first and second currents being arranged to convey said currents upwardly through and beyond said bottom wall so that the speed of ascending air currents decreases between said side walls.

Claim 17

A combination as defined in claim 12 wherein said stream consists of greenleaf tobacco.

Claim 18

A combination as defined in claim 15, further comprising means for compacting conditioned greenleaf tobacco downstream of said third section of said transporting means.

Claim 19

A combination as defined in claim 12, further comprising metering means for supplying said first section of said transporting means tobacco particles at a constant rate.

Claim 20

A combination as defined in claim 12, wherein said transporting means comprises a vibratory conveyor arranged to transport tobacco particles through all of said sections.

Claim 21

A combination as defined in claim 12, wherein said first section comprises a single tobacco conditioning chamber.

Claim 22

A combination as defined in claim 12, further comprising detector means located downstream of said third section for measuring the moisture content of tobacco particles, the means for maintaining the speed, temperature and/or moisture content of at least one of said first and second currents within a predetermined range comprising means for comparing the measured moisture content of the particles with a predetermined moisture content and means for changing the speed, temperature and/or moisture content of said one current as a function of deviations of the measured moisture content of the particles from said predetermined moisture content.

Claim 23

A combination as defined in claim 12, wherein said means for maintaining the speed, temperature and/Or moisture content of said third current within a predetermined range comprises means for maintaining the temperature and moisture content of said third current at a predetermined constant value.

Claim 24

A combination as defined in claim 12, further comprising measuring means for determining the moisture content of tobacco particles in a fourth section of said transporting means located between said second and third sections, the means for maintaining the speed, temperature and/or moisture content of at least one of said first and second currents within a predetermined range comprising means for comparing the measured moisture content of tobacco particles with a predetermined moisture content and means for changing the speed, temperature and/or moisture content of said one current as a function of deviations of the measured moisture content of tobacco particles from said predetermined moisture content.

Claim 25

A combination as defined in claim 12, further comprising means for measuring the moisture content of tobacco upstream of said first section of said transporting means, the means for maintaining the speed, temperature and/or moisture content of at least one of said currents within a predetermined range comprising means for comparing the measured moisture content of tobacco particles with a predetermined moisture content and means for changing the speed, temperature and/or moisture content of said one current as a function of deviations of said measured moisture content of tobacco particles from said predetermined moisture content.