Nebulizers are known in which preheated water is driven in a thin stream against a target so as to break up into small particles which mix with the surrounding air in order to moisturize same. Other systems use ultrasonic vibrations to fragmentize the water stream. It is generally desired to make the particle size as small as possible, preferably of 5 microns or less, so as to facilitate penetration of the water particles into the respiratory tract of a patient. However, the mist produced in this manner is not very stable since the water particles are not uniformly dispersed in the airflow and tend to coalesce, thereby forming larger droplets which settle out prematurely in the supply conduit as well as in the respiratory tract itself. The equipment is relatively inefficient, complex and correspondingly expensive, especially for home use; moreover, unless the water is preboiled, sterile conditions are difficult to maintain.
In U.S. Pat. 3,894,537, which is incorporated herein by reference, I have described an effective steam-air inhalator which gives very satisfactory results. The present invention is an improvement over this patent in that provision is made for incorporating medication in moist air, or oxygen, or oxygen-rich air and also for returning condensate to the steam generator.
It is a general object of this invention to provide an improved inhalator for producing a stable mist of submicron particles.
A further object is to provide means to return condensate formed in the breathing element to the steam generator.
Yet a further object is to provide a means for incorporating volatile medicaments within the mist so that a medicated breathing mist is produced.