Inhaler

Patent metadata

Field	Value
Publication number	US-12089632-B2
Application number	US-202017066918-A
Country	US
Kind code	B2
Filing date	Oct 9, 2020
Priority date	Apr 10, 2018
Publication date	Sep 17, 2024
Grant date	Sep 17, 2024

Abstract

An inhaler includes an atomizing unit including a piezoelectric element substrate having a first IDT including a pair of interlocking comb-shaped electrodes. The atomizing unit is configured to atomize liquid by a surface acoustic wave generated by applying a high-frequency voltage to the pair of interlocking comb-shaped electrodes, and a controller is configured to monitor a resonant frequency of the pair of interlocking comb-shaped electrodes and apply a voltage to the pair of interlocking comb-shaped electrodes at a frequency determined based on the monitored resonant frequency.

First claim

The invention claimed is:

1. An inhaler comprising:
an atomizing unit comprising a piezoelectric element substrate having a first IDT consisting of a pair of interlocking comb-shaped electrodes, wherein the atomizing unit is configured to atomize liquid by a surface acoustic wave generated by applying a high-frequency voltage to the pair of interlocking comb-shaped electrodes; and
a controller configured to
monitor a resonant frequency of the pair of interlocking comb-shaped electrodes; and
apply a voltage to the pair of interlocking comb-shaped electrodes at a frequency determined based on the monitored resonant frequency.

2. The inhaler according to claim 1 , wherein the controller is configured to, when monitoring the resonant frequency, apply a voltage to the pair of interlocking comb-shaped electrodes at a frequency selected from multiple different frequencies and determine as the resonant frequency, a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes when power reflected from the pair of interlocking comb-shaped electrodes is the lowest.

3. The inhaler according to claim 2 , wherein the controller is configured to:
detect first power reflected from the pair of interlocking comb-shaped electrodes when a voltage is applied to the pair of interlocking comb-shaped electrodes at a first frequency;
detect second power reflected from the pair of interlocking comb-shaped electrodes when a voltage is applied to the pair of interlocking comb-shaped electrodes at a second frequency separated from the first frequency by a first value; and
apply a voltage to the pair of interlocking comb-shaped electrodes at a third frequency separated from the second frequency by a second value that is smaller than the first value when the second power is lower than the first power.

4. The inhaler according to claim 2 , wherein the controller is configured to:
monitor reflected power from the pair of interlocking comb-shaped electrodes while discretely increasing or decreasing a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes; and
end a scan when the trend of the value indicating the reflected power shifts from a decreasing trend to an increasing trend, and determine as the resonant frequency, a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes when the reflected power becomes the lowest.

5. The inhaler according to claim 2 , wherein the controller is configured to:
monitor reflected power from the pair of interlocking comb-shaped electrodes while discretely increasing a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes; and
reduce the range of variation in a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes and discretely decrease the frequency when the trend of the value indicating the reflected power shifts from a decreasing trend to an increasing trend.

6. The inhaler according to claim 2 , wherein the controller is configured to:
monitor reflected power from the pair of interlocking comb-shaped electrodes while discretely decreasing a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes; and
reduce the range of variation in a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes and discretely increase the frequency when the trend of the value indicating the reflected power shifts from a decreasing trend to an increasing trend.

7. The inhaler according to claim 2 , wherein the controller is configured to determine a resonant frequency monitored before the start of atomization of the liquid by the atomizing unit, a resonant frequency estimated from the temperature of the piezoelectric element substrate or a frequency closest to the resonant frequency at the time of the previous inhalation as a frequency to be selected first from the multiple different frequencies.

8. The inhaler according to claim 1 , further comprising:
a second IDT located on the piezoelectric element substrate and configured to generate a voltage in response to the surface acoustic wave,
wherein the controller is configured to, when monitoring the resonant frequency, apply a voltage to the pair of interlocking comb-shaped electrodes at a frequency selected from multiple different frequencies and determine as the resonant frequency, a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes when a voltage arising at the second IDT is the highest.

9. The inhaler according to claim 8 , wherein the controller is configured to:
detect a first voltage arising at the second IDT when a voltage is applied to the pair of interlocking comb-shaped electrodes at a first frequency;
detect a second voltage arising at the second IDT when a voltage is applied to the pair of interlocking comb-shaped electrodes at a second frequency separated from the first frequency by a first value; and
apply a voltage to the pair of interlocking comb-shaped electrodes at a third frequency separated from the second frequency by a second value that is smaller than the first value.

10. The inhaler according to claim 8 , wherein the controller is configured to:
monitor a voltage arising at the second IDT while discretely increasing or decreasing a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes; and
end a scan when the trend of the value of a voltage arising at the second IDT shifts from an increasing trend to a decreasing trend, and determine as the resonant frequency, a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes when the voltage becomes the highest.

11. The inhaler according to claim 8 , wherein the controller is configured to:
monitor a voltage arising at the second IDT while discretely increasing a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes; and
reduce the range of variation in the frequency of the voltage applied to the pair of interlocking comb-shaped electrodes and discretely decrease the frequency when the trend of the value of a voltage arising at the second IDT shifts from an increasing trend to a decreasing trend.

12. The inhaler according to claim 8 , wherein the controller is configured to:
monitor a voltage arising at the second IDT while discretely decreasing a frequency of a voltage applied to the pair of interlocking comb-shaped electrodes; and
reduce the range of variation in the frequency of the voltage applied to the pair of interlocking comb-shaped electrodes and discretely increase the frequency when the trend of the value of a voltage arising at the second IDT shifts from an increasing trend to a decreasing trend.

13. The inhaler according to claim 8 , wherein the controller is configured to determine a resonant frequency monitored before the start of atomization of the liquid by the atomizing unit, a resonant frequency estimated from the temperature of the piezoelectric element substrate or a frequency closest to the resonant frequency at the time of the previous inhalation as a frequency to be selected first from the multiple different frequencies.

14. The inhaler according to claim 1 , wherein the controller is configured to monitor the resonant frequency before the start of or after the completion of atomization of the liquid by the atomizing unit.

15. The inhaler according to claim 1 , wherein the controller is configured to monitor the resonant frequency after detecting a request to atomize the liquid.

16. The inhaler according to claim 1 , wherein the controller is configure

Assignees

• Japan Tobacco Inc

Inventors

• Minami Yuki
• Kudo Takahisa
• Inagaki Michihiro
• INOUE Jumpei
• Abe Yuki
• Geernaert Adam
• Rubiconi Franck
• Cox Simon
• Jobanputra Rishi

Classifications

• F24H15/219

  after heating · CPC title

• F24H15/10

  characterised by the purpose of the control · CPC title

• A24F47/00 Primary

  Smokers' requisites not otherwise provided for · CPC title

• A61M15/06

  Inhaling appliances shaped like cigars, cigarettes or pipes · CPC title

• A24F40/30

  Devices using two or more structurally separated inhalable precursors, e.g. using two liquid precursors in two cartridges · CPC title