Breath-actuated nebulizer for medicine inhalation
Breath-actuated nebulizers for delivering medicine are provided, including an outlet port; an opening; and a medicine cup coupled to the opening through a venturi tube. The medicine cup receives a medicine to be delivered through the outlet port, and is coupled to the outlet port. Some embodiments include a jet nozzle coupled to a pressurized gas source and protruding into the medicine cup, and a sleeve in the medicine cup fluidically coupling the venturi tube to the medicine cup and forming a capillary volume with the jet nozzle. In some embodiments, a rib supports a diverter disposed above a nozzle tip to form a radial flow of the pressurized gas away from a nozzle axis. Also provided is a method for manufacturing and using the above nebulizer.
1. A breath-actuated nebulizer for delivering medicine, comprising:
a medicine cup configured to hold the medicine and comprising (i) a first gas inlet configured to permit ambient gas into the medicine cup, (ii) a second gas inlet configured to conduct pressurized gas into the medicine cup, and (iii) an outlet that is configured to direct a combination of the ambient gas, the medicine, and the pressurized gas out of the medicine cup;
a jet nozzle, in fluid communication with the second gas inlet, comprising a jet orifice configured to produce a jet stream of the pressurized gas;
a sleeve coupled to the jet nozzle and defining a pressure passage;
a venturi tube comprising an inlet opening, an outlet opening, and a venturi passage therebetween, and a throat, wherein a cross-sectional area of the venturi passage decreases from the inlet opening to the throat, and increases from the throat toward the outlet opening, and a first hole is positioned at the throat such that the pressure passage is in fluid communication with the first gas inlet and the medicine cup through the first hole; and
a capillary volume defined between the jet nozzle and the sleeve;
wherein, without moving parts of the nebulizer, the pressure passage changes from a first high pressure, when the ambient gas is not drawn into the medicine cup through the venturi tube such that the medicine is not conducted from the medicine cup through a portion of the pressure passage to the capillary volume, to a second low pressure, when the ambient gas is drawn into the medicine cup through the venturi tube such that the medicine is conducted from the medicine cup toward the jet stream by moving through the portion of the pressure passage to the capillary volume.
2. The nebulizer of claim 1 , further comprising a diverter that is configured to transition the jet stream from an axial orientation within the medicine cup to a radial orientation.
3. The nebulizer of claim 1 , wherein the capillary volume forms a gap around the jet orifice.
4. The nebulizer of claim 3 , wherein the jet stream, upon exiting the jet orifice, is diverted into a radial orientation, such that the jet stream impinges upon the medicine drawn up from the capillary volume.
5. The nebulizer of claim 1 , wherein the pressure passage comprises a first portion that is in fluid communication with the throat of the venturi tube and extends-from the venturi tube toward the jet stream, and the pressure passage further comprises a second portion being in fluid communication with the medicine cup to draw the medicine through the second portion of the pressure passage toward the jet stream.
6. The nebulizer of claim 5 , wherein the outlet comprises an outlet port, and the ambient gas is drawn into the medicine cup through the venturi tube when the combination of the ambient gas, the medicine, and the pressurized gas is evacuated from the medicine cup through the outlet port.
7. The nebulizer of claim 3 , further comprising hermetically sealing the capillary volume in the medicine cup, except for the gap around the jet orifice.
8. A method, comprising:
providing a breath-actuated nebulizer for delivering medicine, comprising:
a medicine cup configured to hold the medicine and comprising (i) a first gas inlet configured to permit ambient gas into the medicine cup, (ii) a second gas inlet configured to conduct pressurized gas into the medicine cup, and (iii) an outlet that is configured to direct a combination of the ambient gas, the medicine, and the pressurized gas out of the medicine cup;
a jet nozzle, in fluid communication with the second gas inlet, comprising a jet orifice configured to produce a jet stream of the pressurized gas;
a sleeve coupled to the jet nozzle and defining a pressure passage;
a venturi tube comprising an inlet opening, an outlet opening, and a venturi passage therebetween, and a throat, wherein a cross-sectional area of the venturi passage decreases from the inlet opening to the throat, and increases from the throat toward the outlet opening, and a first hole is positioned at the throat such that the pressure passage is in fluid communication with the first gas inlet and the medicine cup through the first hole; and
a capillary volume defined between the jet nozzle and the sleeve;
wherein, without moving parts of the nebulizer, the pressure passage changes from a first high pressure, when the ambient gas is not drawn into the medicine cup through the venturi tube such that the medicine is not conducted from the medicine cup through a portion of the pressure passage to the capillary volume, to a second low pressure, when the ambient gas is drawn into the medicine cup through the venturi tube such that the medicine is conducted from the medicine cup toward the jet stream by moving through the portion of the pressure passage to the capillary volume;
removing a cap from the medicine cup;
providing medicine to the medicine cup;
placing the cap back on the medicine cup; and
coupling the nebulizer to a pressurized gas source such that a jet stream is created by the jet orifice of the nebulizer, wherein an entirety of a pressurized gas from the pressurized gas source is directed to the jet orifice.
9. The method of claim 8 , wherein coupling the nebulizer to the pressurized gas source comprises coupling the nebulizer to a wall source containing a pressurized gas flow.
10. The method of claim 8 , wherein coupling the nebulizer to the pressurized gas source comprises coupling the nebulizer to a liquefied gas canister.
11. The method of claim 8 , wherein the pressure passage changes to the second low pressure by a respiration event.