Nebulizer vibrating aperture plate drive frequency control and monitoring

Patent metadata

Field	Value
Publication number	US-11660404-B2
Application number	US-202117350562-A
Country	US
Kind code	B2
Filing date	Jun 17, 2021
Priority date	Jul 24, 2013
Publication date	May 30, 2023
Grant date	May 30, 2023

Abstract

A nebulizer has an aperture plate, a mounting, an actuator, and an aperture plate drive circuit ( 2 - 4 ). A controller measures an electrical drive parameter at each of a plurality of measuring points, each measuring point having a drive frequency; and based on the values of the parameter at the measuring points makes a determination of optimum drive frequency and also an end-of-dose prediction. The controller performs a short scan at regular sub-second intervals at which drive current is measured at two measuring points with different drive frequencies. According to drive parameter measurements at these points the controller determines if a full scan sweeping across a larger number of measuring points should be performed. The full scan provides the optimum drive frequency for the device and also an end of dose indication.

First claim

The invention claimed is:

1. A nebulizer, comprising:
a vibrating aperture plate mounted within the nebulizer and driven by an actuator; and
a controller in communication with the actuator and configured to:
perform a short scan measuring an electrical drive parameter associated with the aperture plate;
initiate a full scan of the electrical drive parameter based on the short scan; and
during the full scan, detect end-of-dose of the nebulizer.

2. The nebulizer of claim 1 , wherein the electrical drive parameter is a drive current to the aperture plate.

3. The nebulizer of claim 1 , wherein the controller is configured to initiate the full scan if the short scan measures a change in the electrical drive parameter outside a predetermined tolerance.

4. The nebulizer of claim 1 , wherein the short scan has fewer than five measuring points.

5. The nebulizer of claim 1 , wherein the short scan is performed at regular intervals.

6. The nebulizer of claim 5 , wherein the regular intervals are sub-second intervals.

7. The nebulizer of claim 1 , wherein the full scan has five to three-hundred measuring points.

8. The nebulizer of claim 7 , wherein the full scan has one-hundred to three-hundred measuring points.

9. The nebulizer of claim 1 , wherein the controller is configured to dynamically determine, from the full scan, a frequency associated with a measuring point of the short scan.

10. The nebulizer of claim 9 , wherein the controller is configured to select a frequency value corresponding to lowest electrical drive parameter as a frequency for a measuring point of the short scan.

11. The nebulizer of claim 10 , wherein said lowest electrical drive parameter is determined to correspond to a resonant frequency, and a frequency value for a measuring point of the full scan with lowest electrical drive parameter is stored for use as a measuring point frequency for the short scan.

12. The nebulizer of claim 1 , wherein the controller is configured to, during the full scan:
dynamically perform a plurality of iterations, and
in each iteration, compare the measured electrical drive parameter against a measurement at a previous measuring point to determine the end-of-dose.

13. The nebulizer of claim 12 , wherein the controller is further configured to determine a slope value from the comparison and identify the end-of-dose when the slope value is above a threshold that indicates end-of-dose.

14. A method of operation of a nebulizer comprising a vibrating aperture plate mounted in the nebulizer and driven by an actuator in communication with a controller, wherein the method comprises:
performing a short scan measuring an electrical drive parameter associated with the aperture plate;
initiating a full scan of the electrical drive parameter based on the short scan; and
during the full scan, detecting end-of-dose of the nebulizer.

15. The method of claim 14 , wherein the short scan has fewer than five measuring points and the full scan has five to three-hundred measuring points.

16. The method of claim 14 , further comprising:
initiating the full scan if the short scan measures a change in the electrical drive parameter outside a predetermined tolerance.

17. The method of claim 14 , wherein the short scan is performed at regular intervals.

18. The method of claim 14 , further comprising:
dynamically performing a plurality of iterations during the full scan, and
in each iteration, comparing the measured electrical drive parameter against a measurement at a previous measuring point to determine the end-of-dose.

19. The method of claim 18 , further comprising:
determining a slope value from the comparison and identifying the end-of-dose when the slope value is above a threshold that indicates end-of-dose.

20. A nebulizer, comprising:
a vibrating aperture plate mounted within the nebulizer and driven by an actuator; and
a controller in communication with the actuator and configured to:
perform a short scan measuring an electrical drive parameter associated with the aperture plate, wherein the short scan has fewer than five measuring points;
initiate a full scan of the electrical drive parameter based on the short scan, wherein the full scan has five to three-hundred measuring points; and
during the full scan, compare the measured electrical drive parameter against a measurement at a previous measuring point to detect end-of-dose of the nebulizer.

Assignees

• Stamford Devices Ltd

Inventors

• Grehan Joseph
• Smith Niall

Classifications

• G01N29/22

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