Ultrasonic nebulising device

• US 5,908,158 A
• Filed: 01/07/1998
• Issued: 06/01/1999
• Est. Priority Date: 10/16/1992
• Status: Expired due to Fees

• Current Assignee: Sheiman Ultrasonic Research Foundation Party Limited
• Original Assignee: Sheiman Ultrasonic Research Foundation Party Limited
• Inventors: Cheiman, Vladimir
• Primary Examiner(s): Morris, Lesley D.
• Application Number:
  US09/003,740
• Time in Patent Office: 510 Days
• Field of Search: 239/102.1, 239/102.2, 239/499, 239/304, 261/DIG. 48, 261/DIG. 78, 128/200.16, 128/200.18
• US Class Current: 239/102.2
• CPC Class Codes: A61M 15/0085 using ultrasonics spraying or atomising liquids using ultrasonic vibrations in general B05B17/06
• CPC Class Codes: A61M 15/0086 Inhalation chambers
• CPC Class Codes: B05B 17/0615 spray being produced at the free surface of the liquid or other fluent material in a container and subjected to the vibrations
• CPC Class Codes: Y10S 261/78 Sonic flow

Abstract

The device is designed for nebulizing liquids and for transporting the formed aerosols. It includes components to form a fountain of liquid that is being nebulized, a container holder (4), a container (2) with contact medium (3), an additional container (5) with liquid being nebulized (6), a nebulization chamber (7), a system for transporting the aerosol to the user, an outlet duct (11), and a mechanism for regulation of rate of delivery of aerosol. The nebulization chamber (7) is designed as a double-element structure, composed of an intake tube (8) and an expansion chamber (9). In the bottom of the expansion chamber (9) outlets (10) have been made for the drainage of the non-nebulized liquid back to the section of the container remote from the base of the fountain. This reduces the negative action of the non-nebulized liquid on the effectiveness of nebulization. The expansion chamber (9) which is incorporated into the nebulization chamber (7) ensures a significant reduction in coagulation of the aerosol particles, thus increasing the efficiency of the nebulizer and particle uniformity. The latter effect is likewise heightened by this specifically designed outlet duct (10) which accomplishes a process of gravitational filtration. As a consequence of the movement of the stream in the narrow intake tube (8) there is formation of a differential pressure, enabling transport of the aerosol from the nebulization chamber to the user. The above principles are proposed for application to multi-use and single-used devices.

Claims

1. A nebulizer having a holding chamber adapted to hold liquid to be nebulized, an ultrasonic transducer positioned below the holding chamber and arranged upon activation to cause a fountain of liquid to spout upwardly within the holding chambers an air inlet allowing air to flow to the vicinity of the fountain for nebulization of the liquid as aerosol, and an outlet duct for discharge of the aerosol, the nebulizer comprising a tube positioned in the upper part of the holding chamber such that liquid from the fountain spouts into the lower end of the tube where the aerosol is produced, the tube having a restricted cross-sectional area relative to the chamber such that the kinetic energy of the fountain increases the static pressure of the aerosol within the tube thereby inducing a pressure drop between the tube and the outlet duct which alone is sufficient to propel the aerosol nebulized from the fountain upwardly through the tube to the outlet duct under the assistance of air being drawn into the holding chamber via the air inlet.

2. A nebulizer as claimed in claim 1 wherein the tube opens at its upper end into an expansion chamber in turn communicating with the outlet duct.

3. A nebulizer as claimed in claim 2 wherein the expansion chamber is adapted to contain any un-nebulized drops of liquid issuing from the tube and drain the liquid back into the holding chamber at a location remote from the fountain.

4. A nebulizer as claimed in claim 3 wherein the expansion chamber has a floor extending outwardly and downwardly from the tube and one or more apertures in the floor toward the outside of the expansion chamber adapted to drain liquid into the holding chamber.

5. A nebulizer as claimed in claim 4 wherein the upper part of the expansion chamber is domed allowing un-nebulized liquid to collect on the inside walls of the expansion chamber and drain down those walls to the lower part of the expansion chamber.

6. A nebulizer as claimed in claim 1 wherein the outlet duct opens from one side of the tube adjacent the upper end of the tube which is closed causing any un-nebulized drops of liquid to gather on the walls of the tube or impinge upon the closed upper end of the tube and drain down the walls of the tube into the holding chamber.

7. A nebulizer as claimed in claim 1 wherein the lower end of the tube flares outwardly into the upper part of the holding chamber, causing liquid draining down the walls of the tube to adhere to the outwardly flaring wall before dropping into the liquid in the holding chamber at a location remote from the fountain.

8. A nebulizer as claimed in claim 1 wherein the air inlet is controllable by the user to vary the rate at which the liquid is nebulized.

9. A nebulizer as claimed in claim 8 wherein the air inlet is controllable by relative movement of two components each having an aperture therethrough, said movement bringing the apertures into and out of register.

10. A nebulizer as claimed in claim 1 wherein the liquid to be nebulized is contained within an hermetically closed vessel adapted to be inserted into the holding chamber, the upper part of the vessel being closed by a membrane adapted to be ruptured and opened before use.

11. A nebulizer as claimed in claim 1 wherein at least the holding chamber and the tube are provided as a sealed unit containing the liquid to be nebulized, and wherein the sealed unit is engageable with the remainder of the nebulizer before use and is adapted to be discarded after use.