System and method for improved volume measurement

• US 7,066,029 B2
• Filed: 09/25/2003
• Issued: 06/27/2006
• Est. Priority Date: 09/25/2003
• Status: Active Grant

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Gray, Larry B., Beavis, Russell
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US10/670,977
• Publication Number:
  US 20050066735A1
• Time in Patent Office: 1,006 Days
• Field of Search: 736/49, 731/49, 73/190.3, 732/90.B, 732/90.V, 732/90, 73/190.5, 732/90.R, 731/521.8, 128/203.26, 128/200.14, 128/200.16, 128/203.12, 239/338, 239/381
• US Class Current: 73/649
• CPC Class Codes: A61M 15/0003 with means for dispensing more than one drug
• CPC Class Codes: A61M 15/002 with air flow regulating means
• CPC Class Codes: A61M 15/0045 using multiple prepacked dosages on a same carrier, e.g. blisters
• CPC Class Codes: A61M 15/0048 the dosages being arranged in a plane, e.g. on diskettes
• CPC Class Codes: A61M 15/0065 Inhalators with dosage or measuring devices A61M15/0028 takes precedence; dosage devices incorporated in aerosol cans B65D83/52
• CPC Class Codes: A61M 15/0066 with means for varying the dose size
• CPC Class Codes: A61M 15/0068 Indicating or counting the number of dispensed doses or of remaining doses
• CPC Class Codes: A61M 15/008 Electronic counters
• CPC Class Codes: A61M 15/0085 using ultrasonics spraying or atomising liquids using ultrasonic vibrations in general B05B17/06
• CPC Class Codes: A61M 15/009 using medicine packages with incorporated spraying means, e.g. aerosol cans pocket atomiser of the injector type A61M11/08
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2202/03 Gases in liquid phase, e.g. cryogenic liquids
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/3375 Acoustical, e.g. ultrasonic, measuring means
• CPC Class Codes: A61M 2205/3379 Masses, volumes, levels of fluids in reservoirs, flow rates
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/52 with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: B05B 12/006 Pressure or flow rate sensors
• CPC Class Codes: B05B 12/085 : responsive to flow or pressure of liquid or other fluent material to be discharged B05B1/3006, B05B1/323, B05B7/1254 take precedence
• CPC Class Codes: G01F 1/007 : by measuring the level variations of storage tanks relative to the time
• CPC Class Codes: G01F 17/00 : Methods or apparatus for determining the capacity of containers or cavities, or the volume of solid bodies measuring linear dimensions to determine volume G01B
• CPC Class Codes: G01F 22/00 : Methods or apparatus for measuring volume of fluids or fluent solid material, not otherwise provided for
• CPC Class Codes: G01F 23/14 : by measurement of pressure
• CPC Class Codes: G01H 3/00 : Measuring characteristics of vibrations by using a detector in a fluid G01H7/00, G01H9/00, G01H11/00 take precedence
• CPC Class Codes: G10K 9/04 : by compressed gases, e.g. compressed air

Abstract

An apparatus comprises a variable acoustic source and a microphone, both acoustically coupled to a volume having a fluid region and an air region. The apparatus also can include a processor to determine a volume of the air region based on signals received from the microphone and the variable acoustic source. A fluid valve is coupled to the processor, and is configured to allow an amount of fluid to exit the fluid region associated with the volume of the air region. An atomizer, coupled to the fluid region, is configured to aerosolize at least a portion of the fluid.

Claims

1. An apparatus for metering the volume of an aerosolized fluid, the apparatus comprising:

a chamber comprising a gas region and a fluid region;

an atomizer in fluid communication with the fluid region of the chamber for aerosolizing fluid delivered from the fluid region;

an acoustic source configured to be acoustically coupled to the-gas region of the chamber;

a microphone configured to be acoustically coupled to the gas region of the chamber; and

a processor configured to receive a signal from the microphone, and further configured to determine a volume of the gas region of the chamber based on the received signal and thereby to determine a corresponding volume of aerosolized fluid.

2. The apparatus of claim 1, wherein the acoustic source is embedded on a printed circuit board.

3. The apparatus of claim 1, wherein the microphone is embedded on a printed circuit board.

4. The apparatus of claim 1, wherein a printed circuit board is disposed within a housing, and wherein the printed circuit board defines a first volume and a second volume within the housing.

5. The apparatus of claim 4, wherein the processor is further configured to send a control signal to a valve, the control signal associated with the volume of the gas region of the chamber.

6. The apparatus of claim 5, wherein the control signal includes information associated with releasing an amount of fluid.

7. The apparatus of claim 5, wherein the control signal is further associated with a volume of fluid in aerosolized form.

8. An apparatus for metering the volume of an aerosolized fluid, the apparatus comprising:

a housing containing a first volume and a second volume, the housing configured to be acoustically coupled to a a chamber comprising a gas region and a fluid region;

an atomizer in fluid communication with the fluid region of the chamber for aerosolizing fluid delivered from the fluid region;

a first microphone disposed within the first volume;

a second microphone disposed within the second volume;

a printed circuit board disposed within the housing such that the printed circuit board separates the first volume from the second volume, the printed circuit board including an acoustic source; and

a processor configured to calculate a change in volume of the gas region of the chamber, and thereby to determine a quantity of fluid delivered to the atomizer.

9. The apparatus of claim 8, wherein the printed circuit board further includes the processor.

10. The apparatus of claim 8, wherein the chamber is contained in a removable cassette, and wherein the second volume is acoustically coupled to the chamber by a port.

11. The apparatus of claim 8, wherein the printed circuit board includes an inner layer configured to pass electrical signals.

12. The apparatus of claim 8, wherein the processor is further configured to receive a signal from the first microphone;

receive a signal from the second icrophone; and

output a control signal to a valve, the control signal being associated with the received signal from the first microphone and the received signal from the second microphone.

13. The apparatus of claim 8, wherein the printed circuit board includes a means for pressure equalization between the first volume and the second volume.

14. The apparatus of claim 8, wherein the acoustic source is a piezoelectric speaker.

15. An apparatus for metering the volume of fluid delivered as an aerosol, the apparatus comprising:

an atomizer for aerosolizing fluid;

a housing configured to be in communication with a valve, the housing containing a first volume, a second volume and a third volume including a gas region and a fluid region, the gas region acoustically coupled to the second volume and the fluid region coupled to the atomizer;

a printed circuit board disposed within the housing such that the printed circuit board separates the first volume from the second volume, the printed circuit board including

an acoustic source;

a first microphone disposed within the first volume;

a second microphone disposed within the second volume; and

a processor configured to calculate a change in volume of the gas region and thereby to determine an amount of fluid output to the atomizer.

16. The apparatus of claim 15, wherein the printed circuit board further includes the processor.

17. The apparatus of claim 15, wherein the second volume is acoustically coupled to the third volume by a port.

18. The apparatus of claim 15, wherein the printed circuit board includes an inner layer configured to pass electrical signals.

19. The apparatus of claim 15, wherein the processor is further configured to

receive a signal from the first microphone;

receive a signal from the second microphone; and

output a control signal to the valve, the control signal being associated with the received signal from the first microphone and the received signal from the second microphone.

20. The apparatus of claim 15, wherein the printed circuit board includes a means for pressure equalization between the first volume and the second volume.

21. The apparatus of claim 15, wherein the acoustic source is a piezoelectric speaker.

22. The apparatus of claim 15, wherein the third volume is an air region that is separated from a fluid region by a diaphragm, and wherein the air region and the fluid region form a fixed volume.

23. An apparatus for metering the volume of an aerosolized fluid, the apparatus comprising:

a housing configured to be in communication with a valve;

a printed circuit board disposed within the housing such that the printed circuit board defines a first volume and a second volume including a gas region and a fluid region, the printed circuit board including

an acoustic source;

a first microphone disposed within the first volume;

a second microphone disposed within the second volume; and

a processor configured to calculate a change in volume of the gas region and thereby to determine an amount of fluid output from the fluid region for aerosolization.

24. The apparatus of claim 23, wherein the printed circuit board further includes the processor.

25. The apparatus of claim 23, wherein the printed circuit board includes an inner layer configured to pass electrical signals.

26. The apparatus of claim 23, wherein the processor is further configured to receive a signal from the first microphone;

receive a signal from the second microphone; and

output a control signal to the valve, the control signal being associated with the received signal from the first microphone and the received signal from the second microphone.

27. The apparatus of claim 23, wherein the printed circuit board includes a means for pressure equalization between the first volume and the second volume.

28. The apparatus of claim 23, wherein the acoustic source is a piezoelectric speaker.

29. The apparatus of claim 25, wherein the second volume is an air region that is separated from a fluid region by a diaphragm, and wherein the air region and the fluid region form a fixed volume.