Aerosol generating device with air flow detection
There is provided a method of detecting a plurality of user puffs at an aerosol-generating system including a heater, a controller, and a solid aerosol-forming substrate, the method including: heating, by the heater, the solid aerosol-forming substrate over a period containing the plurality of user puffs; and detecting, by the controller, each of the user puffs based on an electrical resistance of the heater over the period. There is also provided an aerosol-generating system for detecting a plurality of user puffs, the system including: a heater; a solid aerosol-forming substrate; and a controller configured to: cause the heater to heat the solid aerosol-forming substrate over a period containing the plurality of user puffs, and detect each of the user puffs based on an electrical resistance of the heater over the period.
1. A method of detecting a plurality of user puffs at an aerosol-generating system comprising a heater, a controller, and a solid aerosol-forming substrate, the method comprising:
heating, by the heater, the solid aerosol-forming substrate over a period containing the plurality of user puffs; and
detecting, by the controller, each of the user puffs based on an electrical resistance of the heater over the period.
2. The method of claim 1 , wherein said each of the user puffs draws an airflow past the heater, the airflow from said each of the user puffs respectively cooling the heater.
3. The method of claim 2 ,
wherein cooling the heater lowers the electrical resistance of the heater, and
wherein the detecting of said each of the user puffs is based on a lowering of the electrical resistance.
4. The method of claim 3 , wherein the controller detects the lowering of the electrical resistance based on a comparison of the electrical resistance to a lookup table.
5. The method of claim 2 ,
wherein a power to the heater is temporarily increased responsive to the airflow cooling the heater, and
wherein the detecting of said each of the user puffs is based on temporary increases in the power.
6. The method of claim 5 , wherein the controller detects the temporary increases in the power based on a comparison of a rate of change of the power to a threshold level.
7. The method of claim 5 , wherein the power to the heater is adjusted by adjusting a duty cycle of a power signal.
8. The method of claim 5 , wherein the power to the heater is temporarily increased to return the heater to a target temperature.
9. The method of claim 1 , wherein the detecting comprises, by the controller, calculating a temperature of the heater based on the electrical resistance.
10. The method of claim 8 , wherein the detecting comprises, by the controller, comparing the calculated temperature of the heater to a target temperature.
11. The method of claim 1 , wherein the electrical smoking system further comprises a memory, the method comprising recording, by the memory, data regarding the plurality of user puffs.
12. The method of claim 1 , wherein the aerosol-generating system further comprises a measurement circuit configured to measure the electrical resistance of the heater and to provide the electrical resistance to the controller.
13. The method of claim 1 , wherein the heater is directly in contact with the solid aerosol-forming substrate.
14. An aerosol-generating system for detecting a plurality of user puffs, the system comprising:
a heater;
a solid aerosol-forming substrate; and
a controller configured to:
cause the heater to heat the solid aerosol-forming substrate over a period containing the plurality of user puffs, and
detect each of the user puffs based on an electrical resistance of the heater over the period.
15. The system of claim 14 , wherein each of the user puffs draws an airflow past the heater, the airflow from said each of the user puffs respectively cooling the heater.
16. The system of claim 15 ,
wherein cooling the heater lowers the electrical resistance of the heater, and
wherein the controller is further configured to detect said each of the user puffs based on a lowering of the electrical resistance.
17. The system of claim 16 , wherein the controller is further configured to detect the lowering of the electrical resistance based on a comparison of the electrical resistance to a lookup table.
18. The system of claim 15 ,
wherein a power to the heater is temporarily increased responsive to the airflow cooling the heater, and
wherein the controller is further configured to detect said each of the user puffs based on temporary increases in the power.
19. The system of claim 18 , wherein the controller is further configured to detect the temporary increases in the power based on a comparison of a rate of change of the power to a threshold level.
20. The system of claim 18 , wherein the power to the heater is adjusted by adjusting a duty cycle of a power signal.
21. The system of claim 18 , wherein the power to the heater is temporarily increased to return the heater to a target temperature.
22. The system of claim 14 , wherein the controller is further configured to calculate a temperature of the heater based on the electrical resistance.
23. The system of claim 22 , wherein the controller is further configured to detect said each of the user puffs based on comparing the calculated temperature of the heater to a target temperature.
24. The system of claim 14 , further comprising a memory configured to record data regarding the plurality of user puffs.
25. The system of claim 14 , further comprising a measurement circuit configured to measure the electrical resistance of the heater and to provide the electrical resistance to the controller.
26. The system of claim 14 , wherein the heater is directly in contact with the solid aerosol-forming substrate.