Liquid dispensing apparatus and methods

• US 6,085,740 A
• Filed: 04/10/1998
• Issued: 07/11/2000
• Est. Priority Date: 02/21/1996
• Status: Expired due to Fees

• Current Assignee: Novartis Pharma AG (Novartis Ag)
• Original Assignee: Aerogen, Inc. (Nektar Therapeutics)
• Inventors: Ivri, Yehuda, Wu, Cheng H.
• Primary Examiner(s): Weiss, John G.
• Assistant Examiner(s): SRIVASTAVA, VIRENDRA KUMAR
• Application Number:
  US09/058,344
• Time in Patent Office: 823 Days
• Field of Search: 128/200.16, 128/200.14, 128/200.23, 128/203.12, 239/101, 239/406, 239/102
• US Class Current: 128/200.16
• CPC Class Codes: A61M 11/005 using ultrasonics spraying or atomising liquids using ultrasonic vibrations in general B05B17/06
• 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 2205/3306 Optical measuring means
• CPC Class Codes: B05B 12/08 responsive to condition of liquid or other fluent material to be discharged, of ambient medium or of target ; responsive to condition of spray devices or of supply means, e.g. pipes, pumps or their drive means
• CPC Class Codes: B05B 17/0646 Vibrating plates, i.e. plates being directly subjected to the vibrations, e.g. having a piezoelectric transducer attached thereto
• CPC Class Codes: B05B 17/0684 Wicks or the like
• CPC Class Codes: B41J 2/025 by vibration

Abstract

The invention provides methods and apparatus for nebulizing liquids. In one exemplary embodiment, an apparatus is provided which comprises a thin shell member having a front surface, a rear surface, and a plurality of apertures extending therebetween. The apertures are tapered to narrow from the rear surface to the front surface. A liquid supplier is further provided which delivers a predetermined unit volume of liquid to the rear surface. A vibrator vibrates the thin shell member to eject liquid droplets from the front surface of the thin shell member.

Claims

1. An apparatus for nebulizing a liquid, the apparatus comprising:

a dome shaped member comprising a front surface, a rear surface, and a plurality of apertures extending therebetween, said apertures being tapered to narrow from the rear surface to the front surface;

a liquid supplier which delivers liquid to the rear surface such that substantially all of the liquid adheres to the rear surface by surface tension forces; and

a vibrator comprising a vibratable element which vibrates the dome shaped member to eject liquid droplets from the front surface of the dome shaped member.

2. An apparatus as in claim 1, further comprising an acoustical sensor which detects when the unit volume of liquid has been ejected from the dome shaped member.

3. An apparatus as in claim 2, wherein the acoustical sensor comprises a piezoelectric element.

4. An apparatus as in claim 1, wherein the apparatus further comprises a mouthpiece and means for actuating the vibrator when a patient begins to inhale from the mouthpiece.

5. An apparatus as in claim 1, wherein the tapers have a size in the range from about 1 μ

m to 6 μ

m at their narrowest dimension.

6. An apparatus as in claim 1, wherein the liquid comprises a medicament.

7. An apparatus for nebulizing a liquid, the apparatus comprising:

a dome shaped member comprising a front surface, a rear surface, and a plurality of apertures extending therebetween, said apertures being tapered to narrow from the rear surface to the front surface;

a liquid reservoir; and

a liquid-delivery system in fluid communication with the liquid reservoir, said liquid delivery system being disposed to transfer liquid from the reservoir to the rear surface of the dome shaped member such that substantially all of the delivered liquid adheres to the rear surface by surface tension forces; and

a vibrator which vibrates the dome shaped member to eject liquid droplets from the front surface of the dome shaped member.

8. An apparatus as in claim 7, wherein the liquid delivery system comprises a capillary system which comprises a wicking member having a bottom end within the liquid reservoir and a delivery end near the rear surface of the non-planar member and an outer member spaced-apart from the wicking member by a capillary gap so that liquid from the reservoir may be drawn toward the delivery end by capillary action.

9. An apparatus as in claim 8, wherein the wicking member further includes at least one capillary channel at the delivery end so that liquid delivered from the capillary gap may continue its travel to the rear surface of the non-planar member through the capillary channel.

10. An apparatus as in claim 8, wherein a bottom portion of the wicking member is cylindrical in geometry and wherein the outer member includes an annular body which surrounds the wicking member.

11. An apparatus as in claim 8, further comprising a housing having a chamber and a mouthpiece, and wherein the outer member is attached to the housing.

12. An apparatus as in claim 11, wherein the wicking member is attached to the liquid reservoir, and wherein the liquid reservoir is detachably secured to the housing so that the liquid reservoir may be separated from the housing.

13. An apparatus as in claim 8, wherein the wicking member includes a flexible portion so that it may axially flex upon contact with the vibrating member.

14. An apparatus as in claim 8, wherein the liquid reservoir has a concave shape and includes capillary channels which move the liquid toward the capillary gap between the outer member and the wicking member.

15. An apparatus as in claim 7, further comprising a power supply which supplies power to the vibrator.

16. An apparatus as in claim 15, wherein the power supply comprises a rechargeable battery.

17. A method for nebulizing a liquid, the method comprising:

providing a dome shaped member comprising a front surface, a rear surface, and a plurality of apertures extending therebetween, said apertures being tapered to narrow from the rear surface to the front surface;

transferring liquid from a liquid reservoir to place the liquid in contact with the rear surface of the dome shaped member, with substantially all of the delivered liquid adhering to the rear surface by surface tension forces; and

vibrating the dome shaped member to eject the liquid on the rear surface from the front surface, wherein liquid is at least periodically supplied from the liquid reservoir to the rear surface as the dome shaped member is vibrated.

18. A method as in claim 17, further comprising vibrating the dome shaped member until substantially all of the liquid within the reservoir is depleted.

19. A method as in claim 18, wherein the liquid reservoir holds an amount of liquid equal to a unit dosage amount.

20. A method as in claim 17, further comprising providing a housing having a chamber, a mouthpiece, the outer member, and the vibratable dome shaped member, and further comprising attaching the reservoir to the housing prior to vibrating the vibratable dome shaped member.

21. A method as in claim 20, further comprising detaching the housing from the reservoir and washing the housing and reservoir.