HEATING CONTROL ARRANGEMENT FOR AN ELECTRONIC SMOKING ARTICLE AND ASSOCIATED SYSTEM AND METHOD

• US 20140270727A1
• Filed: 03/15/2013
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: RAI STRATEGIC HOLDINGS, INC. (British American Tobacco PLC)
• Original Assignee: R J Reynolds Tobacco Company (R. J. Reynolds Tobacco)
• Inventors: Ampolini, Frederic Philippe, Galloway, Michael Ryan, Ingham, Scott, East, Allen Michael, Kimsey, Glen, Anderson, Keith William, Henry, Raymond C. Jr.
• Granted Patent: US 9,423,152 B2
• Time in Patent Office: Days
• US Class Current: 392/387
• CPC Class Codes: A24F 40/10 Devices using liquid inhalable precursors
• CPC Class Codes: A24F 40/50 Control or monitoring
• CPC Class Codes: F24H 9/0005 for water heaters

Abstract

A method is provided for controlling heating of an aerosol precursor arrangement of an electronic smoking article. An average power is directed from a power source to a heating device arranged to heat the aerosol precursor arrangement and a heating time period commensurately initiated. The average power corresponds to a selected power set point associated with the power source. An actual power directed to the heating device is determined as a product of a voltage at, and a current through, the heating device. The actual power is compared to the average power, and the average power is adjusted to direct the actual power toward the selected power set point. The actual power is periodically determined and compared to the average power, and the average power adjusted toward the selected power set point, until expiration of the heating time period. An associated apparatus and computer program product are also provided.

Claims

1. A method of controlling heating of an aerosol precursor arrangement of an electronic smoking article, comprising:

directing an average power from a power source to a heating device arranged to heat the aerosol precursor arrangement and commensurately initiating a heating time period, the average power corresponding to a selected power set point associated with the power source;

determining an actual power directed to the heating device as a product of a voltage at the heating device and a current through the heating device;

comparing the actual power to the average power;

adjusting the average power directed to the heating device so as to direct the actual power toward the selected power set point; and

periodically determining the actual power, comparing the actual power to the average power, and adjusting the average power to direct the actual power toward the selected power set point, until expiration of the heating time period.

2. A method according to claim 1, wherein initiating a heating time period by directing an average power from a power source to a heating device, further comprises actuating a switch device, in electrical communication between the power source and the heating device, to direct an electrical current flow from the power source to the heating device.

3. A method according to claim 1, further comprising determining a voltage at the heating device by comparing an actual voltage at the heating device to a reference voltage.

4. A method according to claim 3, wherein the actual voltage at the heating device is between a low value of about 2.0 V and a high value of about 4.2 V, and comparing an actual voltage at the heating device to a reference voltage further comprises applying a voltage divider to the actual voltage and comparing the divided voltage to an internal reference voltage of a processor, the divided voltage having low and high values corresponding to the low and high values of the actual voltage.

5. A method according to claim 4, wherein comparing the divided voltage to an internal reference voltage of a processor further comprises comparing the divided voltage to an internal reference voltage greater than the high value of the divided voltage.

6. A method according to claim 4, wherein applying a voltage divider further comprises multiplying the actual voltage at the heating device by a ratio of a second resistor to a sum of a first resistor and the second resistor.

7. A method according to claim 6, wherein applying a voltage divider further comprises applying a voltage divider comprising a first resistor of between about 500 kOhm and about 1000 kOhm, and a second resistor of between about 100 kOhm and about 500 kOhm.

8. A method according to claim 6, wherein applying a voltage divider further comprises applying a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween of between about 1:

1 and about 10;

1.

9. A method according to claim 6, wherein applying a voltage divider further comprises applying a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween of about 5:

1.

10. A method according to claim 6, wherein applying a voltage divider further comprises applying a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween corresponding to a ratio of the internal reference voltage of the processor to the high value of the divided voltage.

11. A method according to claim 4, wherein applying a voltage divider further comprises applying a voltage divider to the actual voltage so as to form a representation of an input voltage to a voltage analog-to-digital converter of a processor.

12. A method according to claim 1, further comprising determining a current through the heating device by determining a voltage drop across a resistor serially disposed between the heating device and the power source.

13. A heating-control apparatus for an aerosol precursor arrangement of an electronic smoking article, comprising:

a heating device arranged to heat the aerosol precursor arrangement;

a power source in communication with the heating device; and

a controller in communication with the heating device and the power source, the controller having a processor configured to at least;

direct the power source to provide an average power to the heating device and commensurately initiate a heating time period, the average power corresponding to a selected power set point associated with the power source determine an actual power directed to the heating device as a product of a voltage at the heating device and a current through the heating device;

compare the actual power to the average power;

adjust the average power directed to the heating device so as to direct the actual power toward the selected power set point; and

periodically determine the actual power, compare the actual power to the average power, and adjust the average power to direct the actual power toward the selected power set point, until expiration of the heating time period.

14. An apparatus according to claim 13, wherein the controller is further configured to actuate a switch device, in electrical communication between the power source and the heating device, to direct an electrical current flow from the power source to the heating device.

15. An apparatus according to claim 13, wherein the controller is further configured to determine a voltage at the heating device by comparing an actual voltage at the heating device to a reference voltage.

16. An apparatus according to claim 15, wherein the actual voltage at the heating device is between a low value of about 2.0 V and a high value of about 4.2 V, and wherein the controller is further configured to apply a voltage divider to the actual voltage and compare the divided voltage to an internal reference voltage of the processor, the divided voltage having low and high values corresponding to the low and high values of the actual voltage.

17. An apparatus according to claim 16, wherein the controller is further configured to compare the divided voltage to an internal reference voltage greater than the high value of the divided voltage.

18. An apparatus according to claim 16, wherein the controller is further configured to multiply the actual voltage at the heating device by a ratio of a second resistor to a sum of a first resistor and the second resistor.

19. An apparatus according to claim 18, wherein the controller is further configured to apply a voltage divider comprising a first resistor of between about 500 kOhm and about 1000 kOhm, and a second resistor of between about 100 kOhm and about 500 kOhm.

20. An apparatus according to claim 18, wherein the controller is further configured to apply a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween of between about 1:

1 and about 10;

1.

21. An apparatus according to claim 18, wherein the controller is further configured to apply a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween of about 5:

1.

22. An apparatus according to claim 18, wherein the controller is further configured to apply a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween corresponding to a ratio of the internal reference voltage of the processor to the high value of the divided voltage.

23. An apparatus according to claim 18, wherein the controller is further configured to apply a voltage divider to the actual voltage so as to form a representation of an input voltage to a voltage analog-to-digital converter of the processor.

24. An apparatus according to claim 13, wherein the controller is further configured to determine a current through the heating device by determining a voltage drop across a resistor serially disposed between the heating device and the power source.

25. A computer program product comprising at least one non-transitory computer readable storage medium having computer program code stored thereon for controlling heating of an aerosol precursor arrangement of an electronic smoking article, the computer program code comprising:

program code for directing an average power from a power source to a heating device arranged to heat the aerosol precursor arrangement and commensurately initiating a heating time period, the average power corresponding to a selected power set point associated with the power source;

program code for determining an actual power directed to the heating device as a product of a voltage at the heating device and a current through the heating device;

program code for comparing the actual power to the average power;

program code for adjusting the average power directed to the heating device so as to direct the actual power toward the selected power set point; and

program code for periodically determining the actual power, comparing the actual power to the average power, and adjusting the average power to direct the actual power toward the selected power set point, until expiration of the heating time period.

26. A computer program product according to claim 25, wherein the program code for initiating a heating time period by directing an average power from a power source to a heating device, further comprises program code for actuating a switch device, in electrical communication between the power source and the heating device, to direct an electrical current flow from the power source to the heating device.

27. A computer program product according to claim 25, further comprising program code for determining a voltage at the heating device by comparing an actual voltage at the heating device to a reference voltage.

28. A computer program product according to claim 26, wherein the actual voltage at the heating device is between a low value of about 2.0 V and a high value of about 4.2 V, and the program code for comparing an actual voltage at the heating device to a reference voltage further comprises program code for applying a voltage divider to the actual voltage and comparing the divided voltage to an internal reference voltage of a processor, the divided voltage having low and high values corresponding to the low and high values of the actual voltage.

29. A computer program product according to claim 28, wherein the program code for comparing the divided voltage to an internal reference voltage of a processor further comprises the program code for comparing the divided voltage to an internal reference voltage greater than the high value of the divided voltage.

30. A computer program product according to claim 28, wherein the program code for applying a voltage divider further comprises program code for multiplying the actual voltage at the heating device by a ratio of a second resistor to a sum of a first resistor and the second resistor.

31. A computer program product according to claim 30, wherein the program code for applying a voltage divider further comprises program code for applying a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween of between about 1:

1 and about 10;

1.

32. A computer program product according to claim 30, wherein the program code for applying a voltage divider further comprises program code for applying a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween of between about 1:

1 and about 10;

1.

33. A computer program product according to claim 30, wherein the program code for applying a voltage divider further comprises program code for applying a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween of about 5:

1.

34. A computer program product according to claim 30, wherein the program code for applying a voltage divider further comprises program code for applying a voltage divider comprising a first resistor and a second resistor, having a resistance ratio therebetween corresponding to a ratio of the internal reference voltage of the processor to the high value of the divided voltage.

35. A computer program product according to claim 28, wherein the program code for applying a voltage divider further comprises program code for applying a voltage divider to the actual voltage so as to form a representation of an input voltage to a voltage analog-to-digital converter of a processor.

36. A computer program product according to claim 25, further comprising program code for determining a current through the heating device by determining a voltage drop across a resistor serially disposed between the heating device and the power source.