Nebulizer with variable flow rate control and associated method

#1. Field of the Invention

#This invention relates to inhalation therapy devices, and more particularly, to the design and construction of a nebulizer which has a variable flow rate control.

#2. Prior Art

#FIG. 1 is a perspective view of the nebulizer device of the present invention;

#FIG. 2 is a cross-sectional view taken along lines 2--2 of FIG. 1 and showing the internal aspects of the nebulizer device of the present invention.

#FIG. 3 is a graph showing the relative nebulization rates produced by the various positions of the siphon jet assembly at a constant gas flow rate into the device.

#Referring first to FIGS. 1 and 2, one can see the manifold 10 of the present invention. The manifold 10 comprises a nebulizer section 12 and an exhaust section 14. The nebulizer section 12 has a nebulization chamber 16 of a generally cylindrical configuration. A gas inlet tube or conduit 18 extends into the chamber 16 from one side thereof, and a gas outlet tube or conduit 20 extends from the chamber 16 on the other side thereof. In the preferred embodiment, the gas inlet 18 and the gas outlet 20 are in substantial axial alignment, i.e. an in-line configuration with the nebulizer chamber 16 depending therefrom. The nebulizer section 12 also includes a uniquely designed siphon jet assembly 22. The siphon jet assembly 22 extends into the chamber 16 from the top thereof and is vertically movable therein. The siphon jet assembly 22 is comprised of a tubular member 24 which extends through a sleeve 25 located on the chamber 16. Tubular member 24 is axially rotatable in sleeve member 25. Adjacent the top 26 of the siphon jet assembly 22 is an outwardly extending flange member 27. Disposed at the other end of the siphon jet assembly 22 is a first nozzle 28. Nozzle 28 is configured to produce a high velocity gas jet stream in the chamber 16. A downwardly extending section 30 is coupled to the siphon jet assembly 22 adjacent the first nozzle 28 and is also of tubular construction. Section 30 has an outwardly extending impact post 32 and a second nozzle 34. Impact post 32 and nozzle 34 are disposed on section 30 so as to be adjacent the first nozzle 28.

#Referring specifically to FIG. 2, one can see that impact post 32 extends outwardly from section 30 so as to be generally perpendicular to the first nozzle 28. Nozzle 34 is also located on section 30 so as to be generally perpendicular to nozzle 28 such that a gas jet from nozzle 28 flows across nozzle 34. In this manner, a venturi effect is created. Hence, siphon jet assembly 22 acts as the venturi means for supplying liquid particles to the gas flowing through chamber 16.

#A vial 36 is joined to the chamber 16 and a liquid supply conduit 38 extends into the vial 36. Conduit 38 is also joined to the downwardly extending section 30 so as to be in flow communication with the second nozzle 34. The vial 36 has a shaped base section 40 which is circumferentially disposed about a bottom section of the vial 36. In the preferred embodiment, the vial 36 includes a generally frusto-conical section 42 with a spherical bottom, and is adapted to contain any of the well known medicaments to be supplied to the respiratory tract as hereinafter described. A funnel member 44 is preferably placed atop the vial 36 and is secured in position when the vial 36 is joined to the chamber 16. Funnel member 44 helps retain the liquid in the vial 16.