US 3894537 A
A nebulizer with a downwardly open housing is seated atop a steam generator whose nozzle penetrates into the housing on one side of a baffle which intercepts the steam issuing from a lateral nozzle orifice. A Venturi fitting connected to a source of pressurized air or oxygen creates suction in a channel partly obstructed by the baffle, the steam being thereby aspirated around the baffle together with ambient air entering the housing from below. The Venturi fitting is part of a hose clipped to the housing, this hose leading to a face mask allowing a patient to inhale the mixture of oxygen and moist air.
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Description (OCR text may contain errors)
United States Patent Camp 14 1 Jul 15, 1975 STEAM NEBULIZER Primary Examiner-Richard A. Gaudet Assistant E.\'uminerHenry .l. Recla 912 t A  Inventor gz gsggg Pa. 23 ve Attorney, Agent, or F1rm-Karl F. Ross; Herbert Dubno  Filed: Feb. 7, 1974  Appl. N0.: 440,350  ABSTRACT A nebulizer with a downwardly open housing is seated 152 U.S. c1 128/193; 128/209 atop a Steam generator whose nozzle penetrates into  hit. Cl A6lm 16/00 the housing on one Side of a baffle which intercepts  Fleld of Search l28/l92-l97, the Steam issuing f a lateral nozzle f A V 210? 261/78 turi fitting connected to a source of pressurized air or D10 76 oxygen creates suction in a channel partly obstructed by the baffle, the steam being thereby aspirated  References cued around the baffle together with ambient air entering UNITED STATES PATENTS the housing from below. The Venturi fitting is part of 3.612.048 10/1971 Takaoka 128/195 a hose pp to the housing, this hose leading to a 3,714.944 2/1973 Price 128/209 face mask allowing a patient to inhale the mixture of man-"essa s l ME OR oxygen and moist air.
11 Claims, 2 Drawing Figures OXYGEN 2 STEAM GENERATOR STEAM NEBULIZER FIELD OF THE INVENTION BACKGROUND OF THE INVENTION Respirators 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 microns or less, so as to facilitate their penetration into the respiratory tract of patient. However, the mist produced in this manner is not very stable since the water particles arenot 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 complex and correspondingly expensive, especially for home use; moreover, unless the water is preboiled, sterile conditions are difficult to maintain.
OBJECTS OF THE INVENTION 1 The general object of my present invention is to provide an improved nebulizer for producing a stable mist, primarily but not exclusively for respiratory purposes as discussed above.
Another object is to provide relatively simple means for producing such a mist under substantially sterile conditions.
SUMMARY OF THE INVENTION I realize these objects, in accordance with my present invention, by providing a nebulizer whose housing has an internal channel partly obstructed by a generally transverse baffle, this housing have an entrance for ambient air communicating with the channel in the'vicinity of thebaffle. A channel inlet on one side of the baffle has means for directing a jet of steam against the baffle whereby steam particles are deflected into the surrounding air to form a mist; this surrounding air is constantly aspirated from the ambient atmosphere through the aforementioned entrance with the aid of suction means communicating with the channel on the opposite side of the baffle at which the channel has an outlet for discharging the mist-laden aspirated air.
It is known, eg from US. Pat. No. 3,351,737, to direct a jet of steam against a deflector inside a vessel to which ambient air is also admitted for generating a hot, moist atmosphere which can be used for facial treatment. Such an atmosphere would not be suitable for inhalation through a face mask since the steam would have to issue under high pressure from the associated vaporizer and would therefore predominate in the air/- water mixture to be delivered to the mask.
In my improved nebulizer the mist-laden air is accelerated, independently of the original steam pressure, by the suction means advantageously comprising a Venturi fitting which is connectable to a source of pressurized gas, specifically air or oxygen in the case of a respirator. The oxygen-rich gas thus mixes with the aspi rated moistened air within the Venturi fitting, the re sulting mixture being permeated by finely distributed water particles which have no tendency to coalesce;
The moisture content and the final temperature of the mixture can be readily adjusted by suitable'proportioning of the vaporizationrate andthe flow rate of the en training gas. I Sincethe source of moisture is steam, th'e"ambient air is not contaminated by the mist-forming step during which thesteam is not only finely dispersed but also cooled to the desired temperature level. ,Although in principle such nebulizer may be-used with a wide variety of Vaporizers, I'p'refer to employ a steam generator of the type disclosed in m y prior ULS. Pat. No. 3,743,780 having a disc harge no'zzle with a lateral orifice rising from a top surface on which the nebulizer'housing can be removablyseated. If that housing. is downwardly open, the top of the steam generator formsa channel bottomwhich mayterrnina teshort of the Venturi fitting toleave a gap forthe entry ofambient. air. If desired. supplemental air. may be admitted into the nebulizer channel and/or directly into the \j enturi fitting through additional portsh- If the Venturi fittingforms part of a'discharge conduit, such as a flexible hose terminatingat a face mask or similar breathing implement, the nebulizer ,housing may be provided with gripper jaws releasably engaging that fitting at theoutlet end'of the channel.
BRIEF DESCRIPTION oF THE DR WING? The, above and other features of my invention will now be described in detail with'reference to the accompanying drawing in which:
FIG. 1 is an elevational view, with parts broken away,
of a respirator including a nebulizer according to my invention; and
FIG. 2is a bottom view of the nebulizer per se.
SPECIFIC DESCRIPTION The apparatus shown in FIG. 1 comprises a vaporizer l of which only the upper part has been shown; thisvaporizer advantageously has the' construction of the steam generator disclosed in my prior U.S.' Pat.'N'o. 3,743,780. A lid 2, overlying a boiling chamber, is formed on its top surface 4 with an arcuate groove 3 (see FIG. 3 of my above-identified prior patentl'encircling a nozzle 5 and an adjoining boss6 giving access to a mounting for a pair of electrodes (not shown) depending from the lid.
A nebulizer 7 according to my invention, designed as an adapter for the vaporizer 1, has a housing 8 with an internal channel 9.open at the bottom, this channel being partly obstructed by a transverse baffle 10 depending from the closed top of the housing. The underside of this closed top is formed with a circular depression -11 accommodating the tip of the nozzle 5 which has a discharge orifice 12 pointing toward the baffle 10. A screw 12, traversing a bore 13 in the closed rear wall of housing 8, secures the nebulizer 7 to the lid 2 of steam generator 1 whose top surface 4 thereupon partly closes the channel 9 from below. It will be noted that, in the illustrated operating position, baffle l0 terminates above lid surface 4 so as to leave free a passage '15 through which steam from orifice 12, deflected downwardly by the baffle 10, may escape together with a certain amount of ambient airentering the channel9 to the right of baffle 10 by way of groove 3.. Housing 8, which consists of somewhat resilient pla stic material, is integral with a pair of oppositely curved gripper jaws 16 (best seen in FIG. 2) designed to clip onto aVenturi fitting 17 at one end of a flexible hose 18 leading to a face mask 19. Fitting l' has twodiamet rically opposite ports 20, engaged by a pair of circular bosses 21 on the jaws 16, as well as two further ports 22 and 23 spaced 90 from ports .20. Port 22, communb eating with channel 9, confronts the discharge orifice 12 across the baffle 10; the opposite port 23 opens directly into the atmosphere. A nipple 24, entering the fitting 17 from below, terminates at the level of ports 20, 22, 23 so as to aspirate mist-laden air from channel 9 and ambient air from'channel 23 upon being connect'ed to. a nonillustrated source of pressurized air or oxygen. Additional ambient air, designed to dilute the aspirated mist. enters'thc channel 9 downstream of baffle 10 through an upper aperture 25 and through-an entrance gap 26 formed between fitting l7 and lid 2;
Face mask 19, of conventional typeg is provided with an elastic head band 27, a nose clip 28 and vent holes 29 for the patients exhalati ons.
The amount of steam evolving from generator 1 should be so chosen, along with the flow rate of compressed air or oxygen (e.'g. 2-8 liters per minute), as to let the mixture arrive at the mask 19 at approximately body temperature, i.e.', about 37C. 1
Because of its low cost and ease of operation, a respirating according to my invention is particularly suitable for home use 1 claim: I
l. A nebulizer comprising a housing provided with an internal channel, a generally transverse baffle partly obstructingsaidchannel, said housing having an entrance for ambient air communicating with said channel in the vicinity of said baffle, inlet means opening into said channel on one side of said baffle for directing a jet of steam thereagainst, a Venturi fitting connectable to a source of pressurized gas communicating with said channel on the opposite side of said baffle for continuously aspirating ambient air through said entrance together with steam particles deflected by said baffle to form a mist, said channel having an outlet at said opposite side for discharging the mist-laden aspirated air,
and a vaporizer having a top surface provided with a steam nozzle rising therefrom, said housing being downwardly open and seated on said top surface, said inlet means including a formation on said housing accommodating said nozzle, said top surface forming a bottom for said channel.
2. A nebulizer as defined in claim 1 wherein said housing is. provided with gripper jaws releasably holding said Venturi fitting.
3. A nebulizeras defined ,in claim 2 wherein said pressurized gas is rich in oxygen, said fitting being part of a conduit terminating in a face mask.
4. The combination defined in claim 1 wherein said top surface terminates short of said Venturi fitting to define at least part of said entrance.
5. The combination defined in claim 4 wherein said Venturifitting is provided with a first lateral port, facing a discharge orifice of said 'nozzle zeroes said baffle, and with a second lateral port open toward the atmosphere for direct entrainment of additional atmospheric air by said pressurized gas.
6. The combination defined in claim 4 wherein said housing is provided with an aperture downstream of said baffle for admitting additional atmospheric air into said channel ahead of said Venturi fitting.
7. The combination defined in claim 1 wherein said pressurized gasis rich in oxygen, further including a breathing implement and a conduit extending from said Venturi fitting to said implement. 8. The combination defined in claim 7 wherein said Venturi fitting is an integral part of said conduit, said housing being provided with gripper jaws releasably holding said Venturi fitting.
9. A nebulizer comprising: i
a housing having a first end, a second end, and an elongated open-sided channel extending therebetween to facilitate the entrance of ambient air into its interior;
a baffle disposed transversely in the interior of said channel terminating short of the open side of said channel, said baffle being spaced from said ends;
inlet means-at'said first end of said housing connectable to a source of steam for training a jet of steam onto said baffle whereby the steam-is deflected toward said open side for mixing with ambient air to form a mist;
suction means, adapted to be connected to a breathing device; at said second end of said housing for continuously aspirating said mist from the region of said open side for delivery to the breathing device;
mounting means on said housing for holding said suction meansv at said second end in a position confronti-ngsaid baffle. v
' 10. A nebulizer as defined in claim 9, further comprisingcover .means outside said housing partly obright. angles tosaid baffle. I