Aerosol generating system having means for determining depletion of a liquid substrate

Patent metadata

Field	Value
Publication number	US-9814263-B2
Application number	US-201113996716-A
Country	US
Kind code	B2
Filing date	Dec 22, 2011
Priority date	Dec 24, 2010
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

There is provided an electrically operated aerosol generating system for receiving an aerosol-forming substrate. The system includes a liquid storage portion for storing liquid aerosol-forming substrate, an electric heater including at least one heating element for heating the liquid aerosol-forming substrate, and electric circuitry for determining depletion of liquid aerosol-forming substrate heated by the heater based on a relationship between a temperature of the heating element and power applied to the heating element. There is also provided a method in an electrically operated aerosol generating system including a liquid storage portion for storing liquid aerosol-forming substrate and an electric heater including at least one heating element for heating the liquid aerosol-forming substrate, the method including determining depletion of liquid aerosol-forming substrate heated by the heater based on a relationship between a temperature of the heating element and power applied to the heating element.

First claim

The invention claimed is:

1. An electrically operated aerosol generating system for receiving a liquid aerosol-forming substrate, the system comprising:
a liquid storage portion configured to store the liquid aerosol-forming substrate;
an electric heater comprising at least one heating element configured to heat the liquid aerosol-forming substrate; and
electric circuitry including a processor programmed to determine a depletion of the liquid aerosol-forming substrate delivered proximate to the electric heater based on a temperature change of the at least one heating element identified by the processor, data corresponding to power, from a power supply via an electrical connection of the electrically operated aerosol generating system, applied to the at least one heating element, and a change in a relationship between the power applied to the at least one heating element and the identified temperature change of the at least one heating element.

2. The electrically operated aerosol generating system according to claim 1 , wherein the processor of the electric circuitry is programmed to estimate an amount of liquid aerosol-forming substrate in the liquid storage portion based on the determined depletion.

3. The electrically operated aerosol generating system according to claim 1 , further comprising a temperature sensor configured to measure a temperature of the at least one heating element, and wherein the processor of the electric circuitry is programmed to monitor the temperature of the at least one heating element as sensed by the temperature sensor and determine depletion of liquid aerosol-forming substrate heated by the electric heater based on the temperature as sensed by the temperature sensor.

4. The electrically operated aerosol generating system according to claim 1 , wherein the processor of the electric circuitry is programmed to apply a predetermined power from the power supply to the at least one heating element.

5. The electrically operated aerosol generating system according to claim 1 , wherein the processor of the electric circuitry is programmed to measure the electrical resistance of the at least one heating element, to ascertain the temperature of the at least one heating element from the measured electrical resistance.

6. The electrically operated aerosol generating system according to claim 5 , wherein the processor of the electric circuitry is programmed to measure the electrical resistance of the at least one heating element by measuring current through the at least one heating element and voltage across the at least one heating element, and to determine the electrical resistance of the at least one heating element from the measured current and voltage.

7. The electrically operated aerosol generating system according to claim 3 , wherein the processor of the electric circuitry is programmed to determine depletion of liquid aerosol-forming substrate heated by the electric heater by monitoring an increase of the sensed temperature over successive heating cycles as the liquid aerosol-forming substrate in the liquid storage portion is consumed.

8. The electrically operated aerosol generating system according to claim 5 , wherein the processor of the electric circuitry is programmed to determine depletion of liquid aerosol-forming substrate heated by the electric heater by monitoring an increase of the ascertained temperature over successive heating cycles as the liquid aerosol-forming substrate in the liquid storage portion is consumed.

9. The electrically operated aerosol generating system according to claim 3 , wherein the processor of the electric circuitry is programmed to determine depletion of liquid aerosol-forming substrate heated by the electric heater by monitoring the rate of increase of the sensed temperature over a portion of each heating cycle, over successive heating cycles as the liquid aerosol-forming substrate in the liquid storage portion is consumed.

10. The electrically operated aerosol generating system according to claim 5 , wherein the processor of the electric circuitry is programmed to determine depletion of liquid aerosol-forming substrate heated by the electric heater by monitoring the rate of increase of the ascertained temperature over a portion of each heating cycle, over successive heating cycles as the liquid aerosol-forming substrate in the liquid storage portion is consumed.

11. The electrically operated aerosol generating system according to claim 3 , wherein the processor of the electric circuitry is programmed to determine depletion of liquid aerosol-forming substrate heated by the electric heater by monitoring an increase in the value of an integral over time of the sensed temperature over a portion of each heating cycle, over successive heating cycles as the liquid aerosol-forming substrate in the liquid storage portion is consumed.

12. The electrically operated aerosol generating system according to claim 5 , wherein the processor of the electric circuitry is programmed to determine depletion of liquid aerosol-forming substrate heated by the electric heater by monitoring an increase in the value of an integral over time of the ascertained temperature over a portion of each heating cycle, over successive heating cycles as the liquid aerosol-forming substrate in the liquid storage portion is consumed.

13. The electrically operated aerosol generating system according to claim 1 , wherein the processor of the electric circuitry is programmed to limit the temperature of the at least one heating element to a maximum temperature, and to determine depletion of aerosol-forming substrate heated by the electric heater by monitoring an amount of power applied to the at least one heating element to maintain the maximum temperature.

14. The electrically operated aerosol generating system according to claim 1 , further comprising a capillary wick configured to convey the liquid aerosol-forming substrate from the liquid storage portion to the electric heater.

15. Electric circuitry for an electrically operated aerosol generating system for receiving a liquid aerosol-forming substrate, the system comprising a liquid storage portion configured to store the liquid aerosol-forming substrate, an electric heater including at least one heating element configured to heat the liquid aerosol-forming substrate, and the electric circuitry,
wherein the electric circuitry includes a processor programmed to determine a depletion of the liquid aerosol-forming substrate delivered proximate to the electric heater and heated by the electric heater based on a temperature change of the at least one heating element identified by the processor, data corresponding to power, from a power supply via an electrical connection of the electric circuitry, applied to the at least one heating element, and a change in a relationship between the power applied to the at least one heating element and the identified temperature change of the at least one heating element.

16. A method, comprising:
providing an electrically operated aerosol generating system comprising a liquid storage portion configured to store a liquid aerosol-forming substrate, and an electric heater comprising at least one heating element configured to heat the liquid aerosol-forming substrate; and
determining, using a processor, a depletion of the liquid aerosol-forming substrate delivered proximate to the electric heater and heated by the electric heater based on a temperature change of the at least one heating element identified by the processor, data corresponding to power applied to the at least one heating element, and a change in a

Assignees

• Cochand Olivier
• Thorens Michel
• Flick Jean-Marc
• Degoumois Yvan
• Philip Morris Products Sa

Inventors

• Cochand Olivier
• Thorens Michel
• Flick Jean-Marc
• Degoumois Yvan

Classifications

• A61M11/042

  electrical · CPC title

• H05B2203/035

  Electrical circuits used in resistive heating apparatus · CPC title

• A61M2205/3368

  Temperature · CPC title

• A61M11/041

  using heaters · CPC title

• A61M2205/3653

  by Joule effect, i.e. electric resistance · CPC title