Incorporating smoke-modifying agents in smoking material rods

Information

  • Patent Grant
  • 6273093
  • Patent Number
    6,273,093
  • Date Filed
    Friday, July 30, 1999
    25 years ago
  • Date Issued
    Tuesday, August 14, 2001
    23 years ago
  • CPC
  • US Classifications
    Field of Search
    • US
    • 131 62
    • 131 108
    • 131 110
    • 131 274
    • 131 302
    • 131 304
    • 131 309
    • 131 300
    • 131 306
  • International Classifications
    • A24B1500
    • A24C500
Abstract
A method of, and apparatus for, incorporating particulate smoke-modifying agent in a smoking material rod, wherein said agent is introduced into a flow of filamentary smoking material to the suction band of a rod making machine, the location of introduction being in the vicinity of the suction band of said machine.
Description




The subject invention relates to the incorporation of particulate smoke-modifying agents in smoking material rods.




It has heretofore been proposed to incorporate a particulate smoke-modifying agent in a tobacco rod of a cigarette. Thus, for example, it has been proposed in GB 1 349 537 to admix encapsulated flavourant with cut tobacco cigarette filler and then to feed the thus obtained mixture to a cigarette rod making machine. It was the proposition of U.S. Pat. No. 5,450,863 to adhere a particulate burn rate substance to adhesive printed on cigarette paper, such that the substance adheres to the paper in accordance with the printed pattern of the adhesive. The cigarette paper so loaded with burn rate modifying substance is then used on a rod making machine for the purpose of making continuous tobacco rod. As will be apparent to those skilled in the art, the proposed method of U.S. Pat. No. 5,450,863 could be used in respect of the incorporation of a particulate smoke-modifying agent in a tobacco rod. It is a teaching of U.S. Pat. No. 4,409,995 that particulate material is deposited on tobacco rod via a bore extending through the garniture tongue of a rod making machine.




It is an object of the subject invention to provide an improved and commercially practical method of incorporating a particulate smoke-modifying agent in a smoking material rod.




The subject invention provides a method of incorporating particulate smoke-modifying agent in a smoking material rod, wherein said agent is introduced into a flow of filamentary smoking material to the suction band of a rod making machine, the location of introduction being in the vicinity of the suction band of said machine and the particulate smoke-modifying agent being conveyed to said location of introduction and being introduced into the flow of smoking material by way of being entrained in a flow of gaseous medium.




By preference the gaseous medium is air.




Preferably, the location of introduction of the smoke-modifying agent into the flow of filamentary smoking material to the suction band of the rod making machine is at the suction band guide rails. Suitably, the path of introduction of the smoke-modifying agent into the flow of smoking material extends through one of the two guide rails. Alternatively, the path of introduction of the smoke-modifying agent extends through a wall bounding a chimney of a rod making machine and extends vertically, or substantially vertically, within the chimney.




Preferably, the location of the introduction of the smoke-modifying particles relative of the width of the curtain of filamentary smoking material flowing to the suction band is such that the particles are deposited on smoking material which has already been deposited on the suction band, and downstream of the said location, further smoking material of the curtain is deposited over the deposited particles, so as to ensure that the particles are other than at the periphery of the smoking material carpet as finally formed at the downstream end of the lower run of the suction band. Suitably, the said location is at a mid zone of the said curtain of smoking material. Thus, for example, the said location may be situate between about 25% and about 60% of the width of said curtain taken from that end thereof from which smoking material is first deposited on the suction band, and preferably between about 25% and about 40%. The advantages of the said location of the introduction of smoke-modifying particles being at a mid zone of the said curtain of smoking material include the minimisation of losses in respect of the smoke-modifying particles passing through the suction band, a better smoking article product wherein loss of smoke-modifying agent to sidestream smoke is minimised, and the maintenance of smoke-modifying particles in the smoking article without substantial loss.




Advantageously, the rate of flow of the smoke-modifying agent to the location of introduction is adjustable relative to the speed of operation of the rod making machine, i.e. with any changes in the flow rate of the smoking material to the suction band, such that the smoke-modifying agent is incorporated at a uniform mass quantity per unit length of the smoking material rod. The smoke-modifying agent may, as a result of employment of the subject invention, be present in the smoking material rod at, for example, 10 to 20 mg per smoking article unit length of the rod, 16 mg for instance.




As an alternative to the flow of smoke-modifying agent to the location of introduction being a continuous flow, the flow may be intermittent, so that in smoking article rods, the product of said machine, the smoke-modifying agent is located at a zone thereof, which zone extends over a fraction only of the length of the rod, at that zone, for example, which accounts for the last few puffs, the last two or three say, in the smoking of a smoking article comprising the rod.




The particulate smoke-modifying agent may comprise, for example, tobacco dust or encapsulated flavourant, menthol for example. In the former case the tobacco dust may be impregnated with a flavourant.




The smoke-modifying agent particles are preferably of spherical shape. The particles may, for example, be of a diameter from about 0.5 mm to about 1.0 mm. The particles used in any particular instance are preferably of uniform diameter. The particles should not be inter-adherent, but on the contrary a bulk of the particles should be free-flowing.




The subject invention further provides a smoking material rod making machine comprising a suction band, filamentary smoking material feed means and smoke-modifying agent feed means, the smoking material feed means being operable to provide a flow of filamentary smoking material to the suction band, the smoke-modifying agent feed means being operable to introduce smoke-modifying agent into said flow, the location of introduction into said flow being in the vicinity of said suction band, and said particulate smoke-modifying agent being conveyed to said location and being introduced into said flow of filamentary smoking material by said smoke-modifying agent feed means by way of said particulate smoke-modifying agent being entrained in a flow of gaseous medium.











In order that the subject invention may be clearly understood and readily carried into effect, reference will now be made, by way of example, to the diagrammatic drawings herewith, in which:





FIG. 1

shows parts of a cigarette rod making machine and associated equipment;





FIG. 2

shows a transverse section, to an enhanced scale, of a first arrangement taken at a trough guide of the making machine of

FIG. 1

;





FIG. 3

shows a transverse section, to an enhanced scale, of a second arrangement taken at a trough guide of the making machine of

FIG. 1

; and





FIG. 4

shows a transverse section, to an enhanced scale, of a third arrangement taken at a trough guide of the making machine of FIG.


1


.











In

FIG. 1

of the drawings herewith parts of a cigarette rod making machine are designated generally by reference numeral


1


. The making machine


1


comprises the well known features of an upwardly extending tobacco-feed chimney


2


, a foraminous, metallic suction band


3


trained about rollers


4


and


5


(one of which is a drive roller), a trough guide


6


and ecreteurs


7


and


8


.




In operation of the making machine


1


, filamentary cut tobacco filler is fed continuously to the lower end of the chimney


2


by conventional feed means (not shown) of the machine


1


and flows upwardly within the chimney


2


(as indicated by arrow T) in an air flow which is maintained under the action of a vacuum which is maintained above the foraminous suction band


3


. At the trough guide


6


the filler is deposited on the under side of the lower run of the suction band


3


and is transported, as a carpet on the band


3


, forwards (leftwards viewing

FIG. 1

, i.e. in the direction of arrow A) to the location of the ecreteurs


7


and


8


, which serve to trim filler from the carpet. As is well known to those skilled in the tobacco art, downstream of the ecreteurs


7


and


8


the tobacco carpet is fed into a garniture (not shown) of the making machine


1


under the action of a transporting garniture band (also not shown) which acts in addition to feed a continuous web of cigarette paper to the garniture. The garniture serves to enwrap the tobacco in the cigarette paper web to provide a continuous tobacco rod. Signals from a rod density monitoring means (also not shown) downstream of the garniture cause position changes of the ecreteurs


7


and


8


such that the amount of tobacco trimmed from the carpet on the suction band


3


is that requisite to maintain the density of the cigarette rod within specified tolerance limits.




As is indicated by

FIGS. 2 and 3

, the trough guide


6


may comprise first and second suction band guide rails


9


and


10


. Extending through a guide rail


9


or


10


is a bore


11


, which bore


11


is in air flow communication with a delivery tube


12


of a capsule delivery unit which in

FIG. 1

is designated generally by reference numeral


13


. The bore


11


may extend through the guide rail


9


or


10


either horizontally, or substantially horizontally, (as depicted in

FIG. 2

) or the bore


11


may extend through the guide rail


9


at an angle θ to the horizontal (as depicted in FIG.


3


). The angle θ may be, for example, about 30°. The vertical distance between the centre line of the bore


11


, when the bore


11


extends horizontally, or substantially horizontally, through the guide rail


9


or


10


, and the underface of the suction band


3


is 20 mm (depicted in

FIG. 2

as x). The vertical distance between the upper surface of the bore


11


, when the bore


11


extends through the guide rail


9


or


10


at an angle of about 30°, and the underface of the suction band


3


is 6 mm (depicted in

FIG. 3

as y).





FIG. 4

shows that the trough guide


6


may alternatively comprise a delivery tube


12


which extends vertically, or substantially vertically, (as viewing

FIG. 4

) within the chimney


2


and trough guide


6


. The vertical distance between the outlet end of the delivery tube


12


and the underface of the suction band


3


is 10 mm (depicted in

FIG. 4

as z). In order to prevent gas/tobacco flow disruptions in the chimney a suitably shaped deflector


50


is positioned about the lower end of the delivery tube


12


. As will be apparent to those skilled in the art transfer means, for example a brush wheel feeder (not shown), may be positioned at the lower end of delivery tube


12


in order to aid in the acceleration of smoke-modifying agent capsules along the vertical, or substantially vertical, tube


12


.




In

FIG. 1

reference numeral


14


designates generally a capsule feed unit comprising a vibratory, gravimetric feeder


15


(which may be a K-Tron (Trade name) KCL24-KV1 feeder) and a refill device


16


. The device


16


comprises a hopper


17


and a pneumatic valve


18


, which valve


18


is operable, under action of a control valve


19


, via an air line


39


, to convey smoke-modifying agent capsules from the hopper


17


to an infeed hopper


20


of the vibratory feeder


15


. The control valve


19


is supplied with air via an air supply line


40


.




The capsule delivery unit


13


comprises a source


21


of pressurised air, an air line


22


, extending from the air source


21


to a pneumatic material transfer unit


23


, and the aforesaid delivery tube


12


. The delivery tube


12


intercommunicates the transfer unit


23


and the aforesaid bore


11


in the suction band guide rail


9


or


10


. The pneumatic material transfer unit


23


. may alternatively be a venturi capsule injector.




In the air line


22


are two pressure regulators


24




a


and


24




b


, two pressure gauges


25




a


and


25




b


, and an adjustable flow restrictor


26


. The pressure regulator


24




a


is operable to control air pressure to the transfer unit


23


and the pressure regulator


24




b


is operable to control the air pressure entering the system . Further, a filter


36


is positioned in the air line


22


to remove air contaminants from the incoming air. A valve


37


positioned in the air line


22


is operable to allow or prevent air flow within air line


22


to the pneumatic material transfer unit


23


.




Reference numeral


42


designates a Programmable Logic Controller (PLC), for example a PLC as manufactured by Allen Bradley model no. SLC500. The PLC is interconnected by signal transmission lines


41


,


43


,


28


,


45


,


46


,


48


and


51


respectively, with a microprocessor


27


, a vacuum switch


44


, operable to detect a blockage within the capsule delivery unit


13


, an encoder


31


, an air pressure detector


38


, operable to detect air pressure in air line


22


, a man-machine-interface (MMI) unit


47


, operable to allow operator input into the system and to display system status, a level sensor


49


of the hopper


17


of the refill device


16


, and the aforementioned valve


37


.




The microprocessor


27


is interconnected by signal transmission lines


41


,


29


and


30


respectively with the PLC


42


, drive means


32


, operable to drive the vibratory feeder


15


, and a weighbridge


33


of a capsule feed unit designated by reference numeral


14


. The microprocessor


27


is also interconnected, by signal transmission line


34


, to the control valve


19


of the conveyor


18


of the refill device


16


.




The encoder


31


, which is interconnected with the drive shaft


52


of the rod making machine


1


, is operable to generate a signal representative of the current speed of operation of the rod making machine


1


.




When the rod making machine


1


is in operation, the capsule delivery unit


13


and the capsule feed unit


14


are operable in conjunction to provide a uniform, continuous and non-pulsed introduction of smoke-modifying agent capsules, through the delivery tube


12


, to the upward flow of cut tobacco filler to the suction band


3


.




In operation of the capsule delivery unit


13


a uniform air flow is established from the pressurised air source


21


, via the line


22


and the transfer unit


23


, to and through the delivery tube


12


. Smoke-modifying agent capsules are fed, at a rate accurably controlled by the capsule feeder unit


14


, to the transfer unit


23


via a hopper


35


thereof, whereupon the capsules are entrained in the air flow and are thus conveyed to and through the delivery tube


12


. Upon emerging from the delivery tube


12


(and the bore


11


, if applicable), the capsules become entrained in the upwardly directed tobacco-conveying air flow and travel with the tobacco filler to the moving suction band


3


.




As is indicated in

FIG. 1

, the location of the introduction of the capsules is at a mid zone of the chimney


2


. This ensures that the capsules are deposited on tobacco filler which has already built up on the suction band


3


upstream of the said location of capsule introduction. As the deposited capsules move forward with the band


3


further deposition of the upwardly flowing filler results in the capsules being located generally centrally of the depth of the filler carpet which passes forwardly to the aforementioned garniture of the rod making machine


1


. This in turn means that the capsules are located generally centrally of the rod formed in the garniture. The capsules are also distributed evenly lengthwise of the rod.




The PLC


42


is operable to ensure that the capsule feed unit


14


feeds capsules to the capsule delivery unit


13


at the feed rate which, relative to the speed of operation of the rod making machine


1


, is that required to attain the specified weight of capsules per unit rod length, which specified weight is selected by the operator via the MMI unit


47


.



Claims
  • 1. A method of incorporating non inter-adherent, free flowing, particulate smoke-modifying agent in a smoking material rod, wherein said agent is introduced into an air entrainment flow of filamentary smoking material to a suction band of a rod making machine, the location of introduction of said agent into said flow being in the vicinity of said suction band and said agent being conveyed by means of a flow of a gaseous medium to said location and being introduced into said flow at said location by way of said agent being entrained in the flow of gaseous medium.
  • 2. A method according to claim 1, wherein said location of introduction is at the suction band guide rail of said machine.
  • 3. A method according to claim 2, wherein the path of introduction of the smoke-modifying agent extends through one of the said guide rails.
  • 4. A method according to claim 1, wherein a path of introduction of the smoke-modifying agent extends through a wall bounding a chimney of said rod making machine and extends vertically, or substantially vertically, within said chimney.
  • 5. A method according to claim 1, wherein said location is situated between about 25% and about 60% of a length of a deposit of said smoking material on said suction band in register with said flow of smoking material to said band taken from an upstream end of said deposit.
  • 6. A method according to claim 5, wherein said location is situated between about 25% and about 40% of said length.
  • 7. A method according to claim 1, wherein a rate of flow of said particulate smoke-modifying agent to said location is adjustable relative to a speed of operation of said rod making machine.
  • 8. A method according to claim 7, wherein said rate of flow of said particulate smoke-modifying agent to said location is adjusted in accordance with any changes in the flow rate of said filamentary smoking material to said suction band.
  • 9. A method according to claim 7, wherein said rate of flow of said particulate smoke-modifying agent to said location is such that the smoke-modifying agent is incorporated at a uniform mass quantity per unit length of said smoking material rod.
  • 10. A method according to claim 9, wherein said uniform mass quantity per unit length of said smoking material rod is 10 to 20 mg per smoking article unit length of the rod.
  • 11. A method according to claim 1, wherein said entrained flow of said particulate smoke-modifying agent in said gaseous medium is intermittent, so that in each smoking article rod produced by said machine the smoke-modifying agent is located at a zone thereof, which zone extends over a fraction only of the length of the rod.
  • 12. A method according to claim 11, wherein said zone of said rod is that zone which accounts for the last few puffs in the smoking of a smoking article comprising said rod.
  • 13. A method according to claim 1, wherein said particulate smoke-modifying agent comprises encapsulated flavourant.
  • 14. A method according to claim 13, wherein said encapsulated flavourant is menthol.
  • 15. A method according to claim 1, wherein said particulate smoke-modifying agent comprises tobacco dust.
  • 16. A method according to claim 15, wherein said agent further comprises a flavourant.
  • 17. A method according to claim 1, wherein the smoke-modifying agent particles are spherical.
  • 18. A method according to claim 17, wherein said smoke-modifying agent particles have a diameter of about 0.5 mm to about 1.0 mm.
  • 19. A method according to claim 17, wherein said smoke-modifying agent particles are of uniform diameter.
  • 20. A method according to claim 1, wherein the smoke-modifying agent particles in bulk are free-flowing.
  • 21. A smoking material rod making machine comprising a suction band, filamentary smoking material feed means and smoke-modifying agent feed means, the smoking material feed means being operable to provide an air entrainment flow of filamentary smoking material to the suction band, the smoke-modifying agent feed means being operable to introduce non inter-adherent, free-flowing, particulate smoke-modifying agent into said flow, the location of introduction of said agent into said flow being in the vicinity of said suction band, and said smoke-modifying agent feed means comprising a pneumatic transfer unit, a gaseous medium supply means, a delivery tube, extending from said transfer unit to said location, and a feed unit, said feed unit being operable to feed a continuous supply of said agent to said transfer unit, said supply means being operable to supply continuously gaseous medium to said transfer unit and through said delivery tube to said location, and said transfer unit being operable to entrain said agent in a thus established flow of said gaseous medium in said delivery tube, whereby in operation of said machine said agent is conveyed to said location by entrainment thereof in said flow of said gaseous medium.
Priority Claims (1)
Number Date Country Kind
9703358 Feb 1997 GB
PCT Information
Filing Document Filing Date Country Kind 102e Date 371c Date
PCT/GB98/00460 WO 00 7/30/1999 7/30/1999
Publishing Document Publishing Date Country Kind
WO98/36650 8/27/1998 WO A
US Referenced Citations (8)
Number Name Date Kind
3046996 Gary Jul 1962
3136321 Davis Jun 1964
3550598 McGlumphy et al. Dec 1970
3991771 Banks Nov 1976
4243056 De La Burde et al. Jan 1981
4409995 Nichols Oct 1983
4993434 Haws et al. Feb 1991
5012823 Keritsis et al. May 1991
Foreign Referenced Citations (8)
Number Date Country
1216170 May 1966 DE
38 21 677 A1 Jan 1990 DE
0 172 654 A1 Feb 1986 EP
0 274 247 A2 Jul 1988 EP
0 405 929 A2 Jan 1991 EP
0 558 447 A1 Sep 1993 EP
1 349 537 Apr 1974 GB
2 108 364 May 1983 GB