Flavor generating article

• US 5,865,185 A
• Filed: 05/24/1995
• Issued: 02/02/1999
• Est. Priority Date: 03/11/1991
• Status: Expired due to Term

• Current Assignee: Philip Morris Incorporated (Altria Group, Inc.), Philip Morris Products Inc (Philip Morris Limited)
• Original Assignee: Philip Morris Incorporated (Altria Group, Inc.)
• Inventors: Scott, G. Robert, Das, Amitabh, Sprinkel, F. Murphy, Ripley, Robert L., Raymond, Wynn R., Nichols, Constance H., Collins, Alfred L., Ritt, Renzer R. Sr., Losee, D. Bruce Jr., Keen, Billy J. Jr., McCafferty, Hugh J., Utsch, Francis V., Wrenn, Susan E., Deevi, Seetharama C., Counts, Mary Ellen, Higgins, Charles T., Lilly, A. Clifton Jr., Houck, Willie G. Jr., Fleischhauer, Grier S., Watkins, Michael L., Lee, Robert E. III
• Primary Examiner(s): Millin, V.
• Assistant Examiner(s): LEWIS, AARON J
• Application Number:
  US08/448,906
• Time in Patent Office: 1,350 Days
• Field of Search: 131/194, 131/329, 131/271, 128/202.21, 128/203.27, 128/200.14
• US Class Current: 131/194
• CPC Class Codes: A24D 1/20 Cigarettes specially adapted for simulated smoking devices
• CPC Class Codes: A24D 3/17 Filters specially adapted for simulated smoking devices
• CPC Class Codes: A24F 40/20 Devices using solid inhalable precursors
• CPC Class Codes: A24F 40/46 Shape or structure of electric heating means
• CPC Class Codes: H05B 3/24 heating conductor being self-supporting
• CPC Class Codes: H05B 3/42 non-flexible
• CPC Class Codes: Y10T 29/49083 Heater type

Abstract

A smoking article is provided in which a replaceable tobacco flavor unit containing tobacco flavor material is electrically heated by a set of permanent reusable heaters to evolve flavors or other components in vapor or aerosol form for delivery to a smoker. Each heater heats only a portion of the available tobacco flavor material so that a plurality of individual puffs of tobacco flavor substance can be delivered sequentially to the smoker. The replaceable tobacco flavor unit can also include a filter to reduce the effect of residual aerosol which settles or condenses on the permanent portions of the article and which can result in undesirable flavor generation when reheated. A method and apparatus for manufacturing the replaceable tobacco flavor unit is also provided.

Claims

1. A smoking article for delivering to a smoker a tobacco flavor substance, said article comprising:

a plurality of electrical heating elements disposed along a permanent cavity;

a source of electrical energy for powering said plurality of electrical heating elements;

control means for applying said electrical energy to said electrical heating elements to selectively heat at least one of said plurality of electrical heating elements; and

a removable tobacco flavor unit comprising;

a carrier having a first end and a second end and having a first surface and a second surface, the first surface defining a flavorant cavity located between said first end and said second end, wherein the second surface is disposed adjacent the plurality of electrical heating elements;

a filter operative upon the predetermined quantity of tobacco flavor substance prior to delivery to the smoker;

tobacco flavor medium disposed on the first surface of said carrier;

wherein when any one of said plurality of electrical heating elements is activated, a respective fraction of said tobacco flavor medium in thermal transfer relationship with said one of said heating means is heated, generating a predetermined quantity of tobacco flavor substance in said flavorant cavity for delivery to the smoker.

2. The article of claim 1 wherein said filter includes

a free-flow filter located adjacent the second end of said carrier and said flavorant cavity, said free-flow filter providing structural support to the tobacco flavor unit.

3. The article of claim 1 wherein:

the carrier forms a substantially hollow cylinder with an inside surface and an outside surface, the plurality of permanent electrical heating elements disposed adjacent the outside surface of the carrier; and

the tobacco flavor medium is disposed on the inside surface of the cylinder wherein the tobacco flavor substance is generated within the carrier;

said tobacco flavor unit further comprising a back-flow resistive element adjacent the first end of said carrier, said back-flow resistive element operative to reduce release of tobacco flavor substance from said first end.

4. The article of claim 3 wherein the back-flow resistive element comprises a substantially cylindrical filter having a surface which forms a part of the flavorant cavity of said carrier.

5. The article of claim 4, said tobacco flavor unit further comprising:

a substantially cylindrical aerosol barrier tube, concentric with and having a diameter larger than the carrier, wherein the inside surface of the barrier tube and the outside surface of the carrier define a region for placement of the plurality of permanent electrical heating elements, the barrier tube reducing the condensation of residual tobacco flavor substance on portions of the permanent cavity of the article.

6. The article of claim 5 wherein:

the substantially cylindrical aerosol barrier tube is attached to the free-flow filter by a collar of material having a large resistance to draw, wherein the collar is used to define the size of the heater placement region of the tobacco flavor unit.

7. The article of claim 2 wherein:

the carrier forms a substantially hollow cylinder with an inside surface and an outside surface, the plurality of permanent electrical heating elements disposed on the inside surface of the carrier; and

the tobacco flavor medium is disposed on the outside surface of the carrier, wherein the tobacco flavor substance is generated outside the carrier;

said tobacco flavor unit further comprising a back-flow resistive element adjacent the first end of said carrier, said back-flow resistive element operative to reduce release of tobacco flavor substance from said first end.

8. The article of claim 7 wherein the free-flow filter and back-flow filter are substantially annular and each has a surface which forms a part of the flavorant cavity for generating the tobacco flavor substance.

9. The article of claim 8, said tobacco flavor unit further comprising:

a substantially cylindrical aerosol barrier tube, concentric with and having a diameter larger than the carrier, wherein the inside surface of the barrier tube and the outside surface of the carrier define the flavorant cavity, the barrier tube reducing the condensation of residual tobacco flavor substance on portions of the permanent cavity of the article.

10. The article of claim 9 further comprising:

a substantially cylindrical plug of material having a large resistance to draw and substantially filling the empty center portion of the free-flow filter.

11. The article of claim 2 further comprising:

a substantially cylindrical mouthpiece filter adjacent the free-flow filter; and

overwrap paper for overwrapping the aerosol barrier tube and mouthpiece filter and for securing the mouthpiece filter to the aerosol barrier tube.

12. The article of claim 1 wherein:

the carrier is composed of a nonwoven carbon fiber mat.

13. The article of claim 12 wherein the carbon fibers in the mat have a basis weight in the range between about 6 g/m² and about 12 g/m².

14. The article of claim 1 wherein the tobacco flavor medium comprises a layer of tobacco material.

15. The article of claim 14 wherein the tobacco flavor medium comprises a continuous sheet of tobacco material.

16. The article of claim 14 wherein the tobacco flavor medium comprises a foam of tobacco material.

17. The article of claim 14 wherein the tobacco flavor medium comprises a gel of tobacco material.

18. The article of claim 14 wherein the tobacco flavor medium comprises a dried slurry of tobacco material.

19. The article of claim 18 wherein the tobacco flavor medium comprises a dried spray-deposited slurry of tobacco material.

20. The article of claim 14 wherein:

the tobacco flavor medium comprises a spatially-varying tobacco flavor medium;

whereby;

the flavor delivery to a smoker varies selectively from puff to puff.

21. The article of claim 1 wherein the control means applies a first amount of said electrical energy to a first heater element and a second amount of said electrical energy to a second heater element so as to selectively vary the flavor delivery from puff to puff for a given tobacco flavor unit.

22. The article of claim 1 wherein the control means applies a first amount of said electrical energy, to each heater element for a first tobacco flavor unit, and a second amount of said electrical energy, to each heater element for a second tobacco flavor unit, so as to selectively vary the flavor delivery from tobacco flavor unit to tobacco flavor unit.

23. The article of claim 1 further including a means for indicating to the smoker that the tobacco flavor unit has been previously inserted into an article and subsequently removed.

24. The article of claim 23 wherein the indicating means must be removed from the tobacco flavor unit before the unit can be inserted into the smoking article.

25. The article of claim 23 wherein the indicating means is a region on the tobacco flavor unit which becomes physically altered upon insertion of the tobacco flavor unit into the smoking article.

26. The article of claim 1 further including a means for indicating to the smoker that the tobacco flavor unit has been previously heated.

27. The article of claim 26 wherein the indicating means is thermally activated and changes color to indicate that the tobacco flavor unit has been previously heated.

28. The article of claim 1 wherein the carrier is composed of a nonwoven carbon fiber mat having a preselected resistivity, and wherein the resistivity corresponds to a particular type of tobacco flavor unit so as to allow the control means of the smoking article to distinguish between different types of tobacco flavor units.

29. The article of claim 1 wherein the tobacco flavor unit further comprises a free-flow tubular element located at the second end of said carrier and adjacent said flavorant cavity, for providing structural support to the tobacco flavor unit.

39. The article of claim 1 or 30 wherein said source of electrical energy comprises a battery.

40. The article of claim 39 wherein said source of electrical energy comprises a charge pump circuit coupled to said battery for boosting the voltage of said battery.

41. The article of claim 40 wherein said battery is disposable.

42. The article of claim 40 wherein said battery is rechargeable.

43. The article of claim 39 wherein said control means includes

means for sequentially selecting members of said plurality of electrical heater elements;

and

a puff sensor operative when a smoker puffs upon said article so as to activate said selected heater element.

44. The article of claim 43 wherein said selecting means is manual.

45. The article of claim 44 wherein said selecting means is automatic.

46. The article of claim 44 wherein said automatic selecting means selects each of said plurality of electrical heating means.

47. The article of claim 45 wherein said control means further comprises sequential indication means for indicating the number of said plurality of electrical heater elements that can be sequentially heated until all of said plurality of electrical heating heater elements have been activated at least once for an associated removable tobacco flavor unit.

48. The article of claim 46 wherein said sequential indication means comprises a liquid crystal display.

49. The article of claim 48 wherein said liquid crystal display indicates when the battery voltage falls below a preselected LOW voltage level by repetitively cycling the display on and off.

50. The article of claim 48 wherein said liquid crystal display indicates when the battery voltage falls below a preselected LOW voltage level and when the battery has been recharged to preselected HIGH voltage level after falling below the preselected LOW voltage level.

51. The article of claim 48 wherein said liquid crystal display indicates when there is no tobacco flavor generating unit loaded into the article.

52. The article of claim 48 wherein said liquid crystal display indicates when there is no heater fixture loaded into the article.

53. The article of claim 45 wherein said pulse applying means applies a pulse of predetermined duration.

54. The article of claim 45 wherein said pulse applying means applies a pulse of predetermined duration in a range from about 0.5 second to about 5 seconds depending on the desired amount of energy that is meant to be delivered to said selected one of said electrical heater elements.

55. The article of claim 45 wherein said pulse applying means applies a pulse of predetermined duration in a range from about 1 second to about 3 seconds depending upon the amount of energy delivered to said selected one of said electrical heater elements.

56. The article of claim 45 wherein said pulse applying means applies a pulse of predetermined duration in a range from about 1 second to about 2seconds depending upon the amount of energy delivered to said selected one of said electrical heater elements.

57. The article of claim 45 wherein said pulse of electrical energy further comprises a pulse of a predetermined amount of electrical energy.

58. The article of claim 45 wherein said predetermined amount of electrical energy ranges from about 5 Joules to about 40 Joules.

59. The article of claim 45 wherein said predetermined amount of electrical energy ranges from about 15 Joules to about 25 Joules.

60. The article of claim 45 wherein said pulse applying means comprises actuation means and applies said pulse in response to actuation of said actuation means by a smoker.

61. The article of claim 45 wherein said actuation means comprises a pressure-sensitive sensor.

62. The article of claim 45 wherein said actuation means is cycled on and off so as to conserve the source of electrical energy.

63. The article of claim 62 wherein said actuation means is on for less than about 50 percent of a given time period.

64. The article of claim 63 wherein said actuation means is on for less than about 20 percent of a given time period.

65. The article of claim 64 wherein said actuation means is on for less than about 5 percent of a given time period.

67. The article of claim 39 wherein said control means further comprises a voltage detector circuit for detecting when the battery voltage falls below a preselected LOW voltage level and for detecting when the battery has been recharged to preselected HIGH voltage level after falling below the preselected LOW voltage level.

68. The article of claim 67 wherein said preselected LOW voltage level is less than about 5 volts and said preselected HIGH voltage level is greater than about 5 volts.

69. The article of claim 68 wherein said preselected LOW voltage level ranges from about 3 to about 3.5 volts and said preselected HIGH voltage level ranges from about 5 to about 6 about volts.

74. The article of claim 1 wherein the tobacco flavor unit further comprises a free-flow tubular element located at the second end of said carrier and adjacent said flavorant cavity, for providing structural support to the tobacco flavor unit.

30. A smoking article for delivering to a smoker a tobacco flavor substance, said article comprising:

a permanent heater fixture including;

a heater base defining a first end of a permanent cavity for receiving a removable tobacco flavor unit, and

a plurality of permanent electrical heater elements disposed on the heater base, said heater elements each having a surface disposed along said permanent cavity;

a source of electrical energy for powering said plurality of heater elements;

control means for applying said electrical energy to said heater elements to selectively heat at least one of said plurality of heater elements; and

a removable tobacco flavor unit received in the heater cavity in proximity to said plurality of heater elements, said tobacco flavor unit including a flavorant cavity and a tobacco flavor medium disposed along said flavorant cavity;

wherein when any one of said plurality of electrical heaters is activated, a respective fraction of said tobacco flavor medium in thermal transfer relationship with said one of said heating elements is heated, generating a predetermined quantity of tobacco flavor substance in said flavorant cavity for delivery to the smoker.

31. The article of claim 30 wherein the permanent cavity is substantially cylindrical;

and wherein the fixture further comprises;

a plurality of heater support fingers disposed from the first end of the heater base for supporting the plurality of heater elements, wherein;

the fingers are elongate, have an inside surface and an outside surface, and are arranged to define a surface of a cylinder.

32. The article of claim 31 wherein the plurality of heater elements are mounted on the inside surface of the heater support fingers.

33. The article of claim 30 wherein the cavity of the heater base forms an annulus;

and wherein the fixture further comprises;

a plurality of heater support fingers disposed from the first end of the heater base for supporting the plurality of heater elements, wherein the fingers are elongate and have an inside surface and an outside surface and are arranged so as to define a surface of a cylinder.

34. The article of claim 33 wherein the plurality of heater elements are mounted on the outside surface of the heater support fingers.

35. The article of claim 32 wherein the plurality of permanent heaters are comprised of silicon semiconductor material.

36. The article of claim 35 wherein the silicon semiconductor material is doped with phosphorous impurities to a level in the range of between about 5×

10¹⁸ impurities/cm³ and about 5×

10¹⁹ impurities/cm³.

37. The article of claim 34 wherein the plurality of permanent heaters are comprised of silicon semiconductor material.

38. The article of claim 37 wherein the silicon semiconductor material is doped with phosphorous impurities to a level in the range of between about 5×

10¹⁸ impurities/cm³ and about 5×

10¹⁹ impurities/cm³.

66. The article of claim 30 wherein said control means comprises a field-programmable logic array.

70. The article of claim 30 wherein the carrier is composed of a nonwoven carbon fiber mat having a preselected resistivity, and wherein the resistivity corresponds to a particular type of tobacco flavor unit so as to allow the smoking article to distinguish between different types of tobacco flavor units.

71. The article of claim 70 wherein said control means includes

means for sequentially selecting members of said plurality of electrical heater elements;

and

a puff sensor operative when a smoker puffs upon said article so as to activate said selected heater element.

72. The article of claim 71 further comprising means to measure the preselected resistivity.

73. The article of claim 72 wherein a first pulse of electrical energy is applied to heat said selected one of said electrical heating elements if a first preselected resistivity is measured, and a second pulse of electrical energy is applied to heat said selected one of said electrical heating elements if a second preselected resistivity is measured.

75. The smoking article of claim 30, wherein said plurality of heaters are located along said heater cavity in spaced-apart relation to said first end of said heater cavity such that when said tobacco flavor unit is fully received in said cavity said plurality of permanent heaters superpose at least a portion of said flavorant cavity.