Power controller and method of operating an electrical smoking system

• US 6,040,560 A
• Filed: 10/16/1997
• Issued: 03/21/2000
• Est. Priority Date: 10/22/1996
• Status: Expired due to Term

• Current Assignee: Charles E.B. Glenn, Philip Morris Products SA (Philip Morris Limited)
• Original Assignee: Philip Morris USA Incorporated (Altria Group, Inc.)
• Inventors: Sano, Masato, Losee, D. Bruce, Nelson, J. Robert Jr., Higgins, Charles T., Ripley, Robert L., Sharpe, David E., Fleischhauer, Grier S., Watkins, Michael L.
• Primary Examiner(s): PASCHALL, MARK H
• Application Number:
  US08/951,255
• Time in Patent Office: 887 Days
• Field of Search: 219/494, 219/497, 219/499, 219/501, 219/505, 219/483, 219/485, 219/486, 219/492, 131/194, 131/270, 131/271, 131/329, 131/273, 128/202.21, 128/202.27
• US Class Current: 219/494
• CPC Class Codes: A24F 40/20 Devices using solid inhalable precursors
• CPC Class Codes: A24F 40/53 Monitoring, e.g. fault detection
• CPC Class Codes: A61M 11/04 operated by the vapour pressure of the liquid to be sprayed or atomised air-humidification, e.g. "room humidifiers" F24F6/00
• CPC Class Codes: A61M 11/041 using heaters
• CPC Class Codes: A61M 15/06 Inhaling appliances shaped like cigars, cigarettes or pipes
• CPC Class Codes: G05D 23/19 characterised by the use of electric means G05D23/1393 takes precedence

Abstract

A novel controller in an electrical smoking system and method, wherein the method includes the steps of: establishing a preferred thermal pathway to be executed with each heater activation responsively to a puff on an electrically heated cigarette; configuring a power cycle in accordance with the desired thermal pathway; dividing the power cycle into at least first and second phases each having a respective, predetermined time period and total energy input for each phase; and adjusting a respective duty cycle (or other power-adjusting factor) in each phase of the power cycle responsively to a voltage reading of the power source such that the established, respective total energy input of each phase is achieved during the time period of each power cycle.

Claims

1. A method of controlling application of electrical power from a power source to heater elements of an electrically operated smoking system, said method comprising the steps of:

establishing in a controller of the electrical smoking system an executable power cycle comprising at least first and second differentiated phases, said establishing step providing each of said first and second differentiated phases with a preselected time period (t_phase), an adjustable duty cycle (dc_phase) and a preselected total energy (J_phase), respectively; and

responsively to a puff on the smoking system, modulating power application to a heater element during each of said first and second differentiated phases in accordance with said established power cycle by;

referencing a voltage of a power source; and

adjusting said duty cycle of said phase responsively to said referencing step such that said respective preselected total energy level of said phase is achievable within said respective preselected time period of said phase.

2. The method as claimed in claim 1, wherein said referencing step comprises the step of referencing both voltage of said power source (v_in) and current through said heater element (i_heater) while applying power to said heater element during said phase.

3. The method as claimed in claim 2, wherein said duty cycle adjusting step comprises modulating a pulse density during said phase.

4. The method as claimed in claim 3, wherein said step of modulating pulse density comprises the steps of:

repetitively generating power pulses, each power pulse having a predetermined duration of on-time (t_on), said repetitively generating step including the step of interposing a duration of off-time (t_off) between consecutive power pulses; and

adjusting said duration of off-time (t_off) during each of said phases responsively to said referencing step.

5. The method as claimed in claim 4, wherein said on-time (t_on) of said power pulses is less than approximately 0.010 second.

6. The method as claimed in claim 5, wherein said on-time (t_on) of said power pulses is approximately 0.008 second.

7. The method as claimed in claim 4, wherein said controller is provided with:

a first set of values indicative of said preselected time periods (t_phase) of said first and a second phases, respectively; and

a second set of values relative to said preselected total energies (J_phase) of said first and a second phases, respectively, said second set of values indicative of a preselected target, average power level (p_phase) for said first and second phases, respectively;

said controller accessing respective values of t_phase and p_phase during each of said first and second phases, respectively;

said controller executing said step of modulating pulse density during each said phase, respectively, by adjusting said duration of off-time (t_off), such that said controller applies power, for the respective time period (t_phase), to said heater element at a level approximating said respective target, average power level (p_phase).

8. The method as claimed in claim 7 further comprising the steps of:

when said duty cycle in any first phase reaches a 100% value, said controller executes said second phase at a 100% duty cycle until such time Tx that a total energy delivered during Tx approximately equals any difference between the preselected total energy of said first phase (J_phase

     1) and actual energy delivery during said first phase together with an energy increment as originally determinable for the Tx portion of said second phase.

9. The method as claimed in claim 7, wherein said step of modulating pulse density includes resolving said duration of off-time (t_off) in accordance with the following relationship:

space="preserve" listing-type="equation">t.sub.off =(i.sub.heater•

v.sub.in•

t.sub.on / p.sub.phase)-t.sub.on.

10. The method as claimed in claim 8, wherein said on-time (t_on) of said power pulses is less than approximately 0.010 second.

11. The method as claimed in claim 7, wherein said step of modulating power application includes a plural execution of said referencing step during each respective phase, said step of adjusting t_off in said respective phase being responsive to said plural referencing steps.

12. The method as claimed in claim 7 further comprising the step of establishing a predetermined range of voltages correlating to a voltage discharge cycle of said power source, said predetermined range including an upper operating voltage level and a lower operating voltage level, said method further comprising the step of limiting execution of said power cycle between said upper operating voltage level and said lower operating voltage level.

13. The method as claimed in claim 1, wherein said power cycle establishing step includes dividing a grand total cycle energy amongst said first and second phases, said total energy of said first phase being greater than said total energy of said second phase, said time period of said second phase being longer than said time period of said first phase.

14. The method as claimed in claim 7, wherein said power cycle establishing step includes dividing a grand total cycle energy amongst said first and second phases, said total energy of said first phase being greater than said total energy of said second phase, said time duration of said second phase being longer than said time duration of said first phase.

15. The method as claimed in claim 14, wherein said power cycle establishing step includes dividing said first phase into a plurality of sub-phases of progressively decreasing total energies.

16. The method as claimed in claim 1, wherein said step of repetitively executing said configured power cycle includes the step of modulating a power application by repetitively generating power pulses, each power pulse having a fixed period of time (t_on) throughout a substantial portion of said power cycle, said duty cycle adjusting step for each respective phase including the step of adjusting a total number of power pulses to be executed during the respective phase responsively to said voltage referencing step.

17. The method as claimed in claim 16, wherein said step of modulating power application includes delivering the respective energy (J_i) of each respective phase in accordance with the following analytical relationships:

space="preserve" listing-type="equation">f.sub.i =(J.sub.i /[t.sub.on.sup.* t.sub.phase i ]) .sup.* (R.sub.h /[v.sub.in *(R.sub.h /(R.sub.h +R.sub.c)].sup.2); and

space="preserve" listing-type="equation">dc.sub.i =t.sub.on.sup.* f.sub.i /t.sub.phase i ;

wherein f_i is the number of power pulses to be generated per second in the respective phase;

J_i is the preselected energy level of the respective phase;

t_on is the period of each power pulse;

R_h is an electrical resistance of the heater element;

R_c is an electrical resistance of circuitry of the controller;

t_phase i is the preselected time period of the respective phase;

v_in is a voltage level referenced from said plural voltage referencing step; and

dc_i is the duty cycle of the respective phase.

18. The method as claimed in claim 17 further comprising the step of electrically referencing at least one of the heater elements to obtain a reading indicative of a detected electrical resistance of said heater element and adjusting the value of J_i in said analytical relationships in compensation of changes in said detected electrical resistance of said heater.

19. The method as claimed in claim 17, wherein said step of modulating power application includes a plural execution of said referencing step during each respective phase, said step of adjusting duty cycle in said respective phase being responsive to said plural referencing steps.

20. The method as claimed in claim 16 further comprising the step of establishing a predetermined range of voltages correlating to a voltage discharge cycle of said power source, said predetermined range including an upper operating voltage level and a lower operating voltage level, said method further comprising the step of limiting execution of said power cycle between said upper operating voltage level and said lower operating voltage level.

21. The method as claimed in claim 20, wherein said step of establishing a power cycle includes the step of preselecting a maximum value of duty cycle at a voltage level in a lower portion of said voltage discharge cycle.

22. The method as claimed in claim 21, wherein said step of preselecting said maximum value of duty cycle is established at a voltage level less than said lower operating voltage level.

23. The method as claimed in claim 16, wherein said power cycle establishing step includes dividing a grand total cycle energy amongst said first and second phases, said total energy of said first phase being greater than said total energy of said second phase, said time period of said second phase being longer than said time period of said first phase.

24. The method of claim 1, wherein said preselected time period (t_phase) of said first phase is different from said preselected time period (t_phase) of said second phase.

25. The method of claim 1, wherein said preselected total energy (J_phase) of said first phase is different from said preselected total energy (J_phase) of said second phase.

26. The method of claim 1, wherein said duty cycle adjusting step is effective for replicating a predetermined thermo-histogram.

27. The method of claim 1, wherein for a given voltage level of the power source voltage, a corresponding duty cycle associated with said first phase is different from a corresponding duty cycle associated with said second phase.

69. The method as claimed in claim 1, further comprising the step of establishing in said controller a preheating cycle executable upon said controller receiving a signal that a cigarette has been inserted into the lighter, said preheating cycle comprising the steps of communicating electrical power to at least some of said heater elements in succession to deliver sufficient energy during said preheating cycle to thermally pre-treat a portion of the inserted cigarette.

70. The method as claimed in claim 69, wherein said energy of said preheating cycle is in the range of approximately 5 to 25 Joules.

71. The method as claimed in claim 70, wherein said energy of said preheating cycle is in the range of approximately 10 to 25 Joules.

72. The method as claimed in claim 71, wherein said energy of said preheating cycle is approximately 17 Joules.

28. A method of controlling the application of power cycles in an electrical smoking system so that the smoking system provides consistent delivery, said smoking system including a source of electrical power, a plurality of heater elements and a controller for controllably communicating at least one of said heater elements with said electrical power source during a power cycle, said method comprising the steps of:

configuring a power cycle in accordance with a desired thermo-histogram, said configuring step including the steps of dividing said power cycle into at least first and second differentiated phases and establishing a respective time period for each phase and establishing a respective total energy for each phase;

establishing a predetermined range of voltages correlating to a discharge cycle of a power source, said predetermined range including an upper voltage level and a lower voltage level;

repetitively executing said configured power cycle upon demand by;

referencing a voltage of said power source; and

adjusting a respective duty cycle in each of said phases responsively to said referencing step such that the established, respective total energy of each phase is achieved during said execution step, whereby repetition of said desired thermo-histogram is achieved along said discharge cycle of said power source.

29. The method as claimed in claim 28, wherein said referencing step comprises the step of referencing both voltage of said power source (v_in) and current through said heater element (i_heater) while applying power to said heater element during said phase.

30. The method as claimed in claim 29, wherein said duty cycle adjusting step comprises modulating a pulse density during said phase.

31. The method as claimed in claim 30, wherein said step of modulating pulse density comprises the steps of:

repetitively generating power pulses, each power pulse having a predetermined duration of on-time (t_on), said repetitively generating step including the step of interposing a duration of off-time (t_off) between consecutive power pulses; and

adjusting said duration of off-time (t_off) during each of said phases responsively to said referencing step.

32. The method as claimed in claim 31, wherein said controller is provided with:

a first set of values indicative of said preselected time periods (t_phase) of said first and second phases, respectively; and

a second set of values relative to said preselected total energies (J_phase) of said first and a second phases, respectively, said second set of values indicative of a preselected target, average power levels (p_phase) for said first and second phases, respectively;

said controller accessing respective values of t_phase and p_phase during each of said first and second phases, respectively;

said controller executing said step of modulating pulse density during each said phase, respectively, by adjusting said duration of off-time (t_off), such that said controller applies power, for the respective time period (t_phase), to said heater element at a level approximating said respective target, average power level (p_phase).

33. The method as claimed in claim 32 further comprising the steps of:

when said duty cycle in any first phase reaches a 100% value, said controller executes said second phase at a 100% duty cycle until such time Tx that a total energy delivered during Tx approximately equals any difference between the preselected total energy of said first phase (J_phase

     1) and actual energy delivery during said first phase together with an energy increment originally determinable for the Tx portion of said second phase.

34. The method as claimed in claim 28, wherein said step of repetitively executing said configured power cycle includes the step of modulating a power application by repetitively generating power pulses, each power pulse having a fixed period of time (t_on) throughout a substantial portion of said power cycle, said duty cycle adjusting step for each respective phase including the step of adjusting a total number of power pulses to be executed during the respective phase responsively to said voltage referencing step.

35. The method as claimed in claim 34, wherein said step of modulating power application includes delivering the respective energy (J_i) of each respective phase in accordance with the following analytical relationships:

space="preserve" listing-type="equation">f.sub.i =(J.sub.i /[t.sub.on.sup.* t.sub.phase i ]) .sup.* (R.sub.h /[v.sub.in *(R.sub.h /(R.sub.h +R.sub.c)].sup.2); and

space="preserve" listing-type="equation">dc.sub.i =t.sub.on.sup.* f.sub.i /t.sub.phase i ;

wherein f_i is the number of power pulses to be generated per second in the respective phase;

J_i is the preselected energy level of the respective phase;

t_on is the period of each power pulse;

R_h is an electrical resistance of the heater element;

R_c is an electrical resistance of circuitry of the controller;

t_phase i is the preselected time period of the respective phase;

v_in is a voltage level referenced from said plural voltage referencing step; and

dc_i is the duty cycle of the respective phase.

36. The method as claimed in claim 35 further comprising the step of electrically referencing at least one of the heater elements to obtain a reading indicative of a detected electrical resistance of said heater element and adjusting the value of J_i in said analytical relationships in compensation of changes in said detected electrical resistance of said heater.

37. The method as claimed in claim 34 further comprising the step of limiting execution of said configured power cycle between said upper operating voltage level and said lower operating voltage level.

38. The method as claimed in claim 37, wherein said step of configuring a power cycle includes the step of preselecting a maximum value of duty cycle at a voltage level in a lower portion of said voltage discharge cycle.

39. The method as claimed in claim 38, wherein said step of preselecting said maximum value of duty cycle is established at a voltage level less than said lower operating voltage level.

40. The method as claimed in claim 28, wherein said power cycle configuring step includes dividing a total cycle energy among first and second phases, said respective energy level of said first phase being two-thirds of said total cycle energy, said respective energy level of said second phase being one-third of said total cycle energy.

41. The method of claim 28, wherein said time period of said first phase is different from said time period of said second phase.

42. The method of claim 28, wherein said total energy of said first phase is different from said total energy of said second phase.

43. The method of claim 28, wherein for a given voltage level of the power source voltage, a corresponding duty cycle associated with said first phase is different from a corresponding duty cycle associated with said second phase.

80. The electrical lighter as claimed in claim 29, wherein said energy of said preheating cycle is in the range of approximately 10 to 25 Joules.

81. The electrical lighter as claimed in claim 80, wherein said energy of said preheating cycle is approximately 17 Joules and the time duration of each power communication is approximately 1/8 second.

82. The electrical lighter as claimed in claim 81, wherein said the time duration of each power communication is approximately 1/8 second for each of eight heaters.

44. An electrical cigarette lighter comprising:

a source of electrical power having a predetermined range of voltages correlating to a discharge cycle of said power source, said predetermined range including an upper voltage level and a lower voltage level;

a plurality of heater elements adapted to receive a cigarette; and

a controller for controllably communicating at least one of said heater elements with said electrical power source responsively to a puff on said cigarette;

said controller configured to deliver electrical energy to said at least one heater in accordance with a predetermined power cycle including at least first and second differentiated phases, a preselected time period for each phase and a preselected energy level for each phase;

said controller including means for repetitively executing said configured power cycle, said means for repetitively executing said configured power cycle comprising;

means for referencing voltage of said power source; and

means for adjusting a respective duty cycle in each of said phases responsively to an output of said voltage referencing means such that the preselected energy level of each phase is achieved within said preselected time period of each phase during execution of said power cycle, whereby repetition of said predetermined power cycle is achieved along said discharge cycle of said power source.

45. The lighter as claimed in claim 44, wherein said means for repetitively executing said configured power cycle further comprises means for referencing current through said heater element (i_heater);

said means for adjusting duty cycle comprising means for modulating a pulse density during each of said phases responsively to said voltage referencing means and said current referencing means.

46. The lighter as claimed in claim 45, wherein said means for modulating pulse density comprises:

means for repetitively generating power pulses, each power pulse having a predetermined duration of on-time (t_on), together with a duration of off-time (t_off) being interposed between consecutive power pulses; and

means for adjusting said duration of off-time (t_off) during each of said phases responsively to said voltage and current referencing means.

47. The lighter as claimed in claim 46, wherein said on-time (t_on) of said power pulses is less than approximately 0.010 second.

48. The lighter as claimed in claim 47, wherein said on-time (t_on) of said power pulses is approximately 0.008 second.

49. The lighter as claimed in claim 46, wherein said controller further comprises means for accessing:

a first set of values indicative of said preselected time periods (t_phase) of said first and a second phases, respectively; and

a second set of values of relative to said preselected total energies (J_phase) of said first and a second phases, respectively, said second set of values indicative of a preselected target, average power level (p_phase) for said first and second phases, respectively;

said controller accessing respective values of t_phase and p_phase during each of said first and second phases, respectively;

said modulating pulse density means adjusting said duration of off-time (t_off), such that said controller applies power, for the respective time period (t_phase), to said heater element at a level approximating said respective target, average power level (p_phase) during each said phase, respectively.

50. The lighter as claimed in claim 45, wherein said controller is configured to execute said second phase at a 100% duty cycle if said duty cycle in said first phase reached a 100% value, until such time Tx that a total energy delivered during Tx approximately equals any difference between the preselected total energy of said first phase (J_phase 1) and actual energy delivery during said first phase together with an energy increment as originally determinable for the Tx portion of said second phase.

51. The lighter as claimed in claim 45, wherein said controller is configured to limit execution of said power cycle between said upper operating voltage level and said lower operating voltage level.

52. The lighter as claimed in claim 45, wherein said power cycle establishing step includes dividing a grand total cycle energy amongst said first and second phases, said total energy of said first phase being greater than said total energy of said second phase, said time duration of said second phase being longer than said time duration of said first phase.

53. The lighter as claimed in claim 45, wherein said power cycle includes said first phase divided into a plurality of sub-phases of progressively decreasing total energies.

54. The electrical lighter as claimed in claim 44, wherein said controller includes means for repetitively generating power pulses, each power pulse having a fixed period of time (t_on) throughout a substantial portion of said power cycle, said duty cycle adjusting means including means for modulating a total number of power pulses to be executed during the respective phase responsively to the output of said voltage referencing means.

55. The electrical lighter as claimed in claim 54, wherein said fixed period of said power pulses is less than approximately 0.010 second.

56. The electrical lighter as claimed in claim 55, wherein said fixed period of said power pulses is less than approximately 0.008 second.

57. The electrical lighter as claimed in claim 54, wherein said voltage referencing means initially references the voltage of said power source as each respective phase is initiated, said modulating means being responsive to said initial referencing by said voltage referencing means.

58. The electrical lighter as claimed in claim 48, wherein said voltage referencing means references the voltage of said power source a plurality of times within each respective phase, said modulating means responsive to said plurality of referencing by said voltage referencing means.

59. The electrical lighter as claimed in claim 58, wherein said modulating means delivers the respective energy (J_i) of each respective phase in accordance with the following analytical relationships:

space="preserve" listing-type="equation">f.sub.i =(J.sub.i /[t.sub.on.sup.* t.sub.phase i ]) .sup.* (R.sub.h /[v.sub.in *(R.sub.h (R.sub.h +R.sub.c)].sup.2); and

space="preserve" listing-type="equation">dc.sub.i =t.sub.on.sup.* f.sub.i /t.sub.phase i ;

wherein f_i is the number of power pulses to be generated per second in the respective phase;

J_i is the preselected energy level of the respective phase;

t_on is the period of each power pulse;

R_h is an electrical resistance of the heater element;

R_c is an electrical resistance of circuitry of the controller;

t_phase i is the preselected time period of the respective phase;

v_in is a voltage level referenced from said plural voltage referencing step; and

dc_i is the duty cycle of the respective phase.

60. The electrical lighter as claimed in claim 59 further comprising means for electrically referencing at least one of the heater elements to obtain a reading indicative of a detected electrical resistance of said heater element and adjusting the value of J_i in said analytical relationships in compensation of changes in said detected electrical resistance of said heater.

61. The electrical lighter as claimed in claim 54, further comprising means limiting execution of said power cycle between said upper operating voltage level and said lower operating voltage level.

62. The electrical lighter as claimed in claim 61, wherein said modulating means establishes a maximum value of duty cycle at a voltage level in a lower portion of said voltage discharge cycle.

63. The electrical lighter as claimed in claim 62, wherein said step of preselecting said maximum value of duty cycle is established at a voltage level less than said lower operating voltage level.

64. The electrical lighter as claimed in claim 54, wherein said controller is configured to execute a total cycle energy with said first and second phases, said energy level of said first phase being two-thirds of said total cycle energy, said energy level of said second phase being one-third of said total cycle energy.

65. The electrical lighter as claimed in claim 44 further comprising a cigarette detector adapted to provide said controller a signal indicative of a cigarette being inserted into said lighter and puff sensor adapted to provide said controller a signal indicative of a smoker drawing upon the inserted cigarette;

said controller being configured to execute a preheating power cycle responsively to said controller receiving said signal that a cigarette has been inserted into the lighter, said preheating cycle comprising the steps of communicating electrical power to at least some of said heater elements in succession to deliver sufficient energy during said preheating power cycle to thermally pre-treat a portion of the inserted cigarette.

66. The electrical lighter as claimed in claim 65, wherein said energy of said preheating power cycle is in the range of approximately 5 to 25 Joules.

67. The electrical lighter as claimed in claim 64, wherein said energy of said preheating power cycle is in the range of approximately 10 to 25 Joules.

68. The electrical lighter as claimed in claim 66, wherein said energy of said preheating power cycle is approximately 17 Joules.

73. The electrical cigarette lighter of claim 44, wherein said preselected time period of said first phase is different from said preselected time period of said second phase.

74. The electrical cigarette lighter of claim 44, wherein said preselected energy level of said first phase is different from said preselected energy level of said second phase.

75. The electrical lighter of claim 44, wherein said means for adjusting the respective duty cycle in each of said phases is effective for replicating respective predetermined thermo-histograms in each of said phases.

76. The electrical lighter of claim 44, wherein for a given voltage level of the power source voltage, a corresponding duty cycle associated with said first phase is different from a corresponding duty cycle associated with said second phase.

77. An electrical lighter operative with a cigarette, said electrical lighter comprising:

a source of electrical power;

a plurality of heater elements adapted to receive a cigarette; and

a cigarette detector adapted to provide said controller a first signal indicative of a cigarette being inserted into said lighter;

a puff sensor adapted to provide said controller a second signal indicative of a smoker drawing upon an inserted cigarette;

a controller configured to execute a puff-actuated power cycle of controllably communicating at least one of said heater elements with said electrical power source responsively to said second signal from said puff sensor;

said controller being further configured to execute a preheating power cycle upon said controller receiving said first signal from said cigarette detector, said preheating cycle comprising the steps of communicating electrical power to at least some of said heater elements in succession to deliver sufficient energy to thermally pre-treat a portion of the inserted cigarette.

78. The electrical lighter as claimed in claim 77, wherein said controller is configured to complete an execution of said preheating cycle prior to initiating said puff-actuated power cycle.

79. The electrical lighter as claimed in claim 77, wherein said energy of said preheating cycle is in the range of approximately 5 to 25 Joules.