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WO1991016991A1 - Atomiseur reglable avec precision - Google Patents

Atomiseur reglable avec precision Download PDF

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Publication number
WO1991016991A1
WO1991016991A1 PCT/US1991/003154 US9103154W WO9116991A1 WO 1991016991 A1 WO1991016991 A1 WO 1991016991A1 US 9103154 W US9103154 W US 9103154W WO 9116991 A1 WO9116991 A1 WO 9116991A1
Authority
WO
WIPO (PCT)
Prior art keywords
liquid
gas
propellant gas
edge
reducing
Prior art date
Application number
PCT/US1991/003154
Other languages
English (en)
Inventor
Darrel R. Resch
Murray K. Lemons
Elisha W. Erb
Original Assignee
Resch D R
Lemons Murray K
Erb Elisha
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Resch D R, Lemons Murray K, Erb Elisha filed Critical Resch D R
Publication of WO1991016991A1 publication Critical patent/WO1991016991A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B1/00—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means
    • B05B1/26—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with means for mechanically breaking-up or deflecting the jet after discharge, e.g. with fixed deflectors; Breaking-up the discharged liquid or other fluent material by impinging jets
    • B05B1/262—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with means for mechanically breaking-up or deflecting the jet after discharge, e.g. with fixed deflectors; Breaking-up the discharged liquid or other fluent material by impinging jets with fixed deflectors
    • B05B1/265—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with means for mechanically breaking-up or deflecting the jet after discharge, e.g. with fixed deflectors; Breaking-up the discharged liquid or other fluent material by impinging jets with fixed deflectors the liquid or other fluent material being symmetrically deflected about the axis of the nozzle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
    • B05B7/02—Spray pistols; Apparatus for discharge
    • B05B7/04—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge
    • B05B7/0416—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge with arrangements for mixing one gas and one liquid
    • B05B7/0433—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge with arrangements for mixing one gas and one liquid with one inner conduit of gas surrounded by an external conduit of liquid upstream the mixing chamber

Definitions

  • prior known pneumatic atomizer and nebulizer devices are based upon a principle in accordance with which a propellant gas is forced through a narrow orifice .into contact with a thin film or stream of liquid which is fed to the periphery or outlet of the orifice. At this location the thin film or stream of liquid is entrained in the propellant gas flowing out of the orifice and broken into ⁇ roplets, which are carried away by the flowing gas.
  • Such known pneumatic nebulizers and atomizers have several disadvantages. Most such nebulizers are not effective in emitting a fog of liquid particles which, is both dense and composed of fine liquid particles when operated with the propellant gas at pressures less than about 5 p.s.i. If the propellant gas is at a pressure less than about 5 p.s.i., either the fog emitted by the pneumatic atomizer will be thin, or the liquid particles within the fog will be large, depending on the design of the pneumatic atomizer and on the amount of liquid supplied to the pneumatic atomizer.
  • the propellant gas pressure is less than 5 p.s.i., and the amount of liquid supplied to the pneumatic atomizer is not sharply reduced, the liquid particles in the emitted fog will be unacceptably large, with resulting fall-out of liquid from the emitted fog.
  • the difficulty with placing an impactor or other barrier in the path of the emitted fog to capture larger particles in the emitted fog is that a means must be provided to collect the liquid that comes into contact with the impactor or barrier, and a means mus be provide ** *- * ⁇ t-.n recirculate the collected liquid or otherwise dispose of the collected liquid.
  • the devices covered by the foregoing patents may be regarded as comprising the following elements: 1) A surface on which the liquid to be atomized is spread, resulting in a film of the liquid on the surface;
  • the pressure of the gas upstream of the filming surface may be at atmospheric pressure if the ambient pressure over the filming surface is at a vacuum, as is the case in an internal combustion engine intake manifold.
  • the consequential point is that there be a pressure drop between a point upstream of the filming surface and the front side of the filming surface to cause the gas to flow from such point, through the orifices in the f ilming surface, to the front side of the filming surface. This drop in pressure is called the pressure head.
  • gas flowing through the orifices in the filming surface entrains liquid drawn from the liquid film on the filming surface, which entrained liquid is drawn into ribbons, which ribbons break into shreds, which shreds collapse into droplets .
  • the droplets are then carried off by the flowing gas.
  • the liquid film must be as thin as possible where it meets the flowing gas; (ii) the conditions where the liquid film and flowing gas meet should be such as to encourage the liquid in the liquid film being entrained in the flowing gas as thin ribbons of liquid; and (iii) the flowing gas should be moving at the point where it encounters the liquid with the highest velocity obtainable with the available pressure head.
  • the prior art such as the patents to Metcalfe,
  • U.S. Patent No. 1,436,351 and the Erb and Resch U.S. Patent No. 4,161,282 teach various means and devices for making a thin liquid film on a filming surface that has one or more orifices through the filming surface.
  • the prior art does not teach designing the atomizer to enhance the entrainment of the liquid into the flowing gas as thin ribbons of liquid, nor does the prior art teach designing the atomizer to maximize the velocity of the gas flow at the point where the flowing gas encounters the liquid.
  • the pressurized gas used to operate the pneumatic atomizer is supplied by means of a conduit that directs the pressured gas to a chamber within the pneumatic atomizer.
  • This chamber is hereinafter called the "the gas chamber.”
  • the gas chamber has ne or more orifices passing through a wall of the gas chamber to the exterior of the atomizer. Such orifices are hereinafter called “the gas orifice.”
  • the exterior surface of such wall serves as a filming surface on which is located the liquid to be atomized.
  • the liquid to be atomized is directed onto the filming surface as a thin film, which film extends around the periphery of the gas orifice.
  • the inner wall of the gas chamber near and about the inner edge of each gas orifice is approximately perpendicular to the centerline of the gas orifice. Stated in other words, the width of the gas chamber measured at the inner edge of the gas orifice is substantially greater than the width of the gas orifice.
  • the pressurized gas passes from a space of relatively large width to a space of relatively small width as the pressurized gas passes from the gas chamber into the gas orifice. It also means the transition occurs suddenly. The sudden transition is due to the approximately right angle relationship between the sidewall of the gas orifice and the inner adjoining wall of the gas chamber .
  • the approximately right angle relationship of the sidewall of the gas orifice and the adjoining inner wall of the gas chamber is hereinafter called a "sharp edge.”
  • the gas orifice's sharp inner edge and the laws of fluid dynamics applicable to the flow of a pressurized gas flowing from a large container through a small sharp edged orifice in the wall of the container results in the gas exiting the gas orifice with a velocity that is not constant across the width of the gas orifice.
  • the gas flowing through the center of the gas orifice will have the fastest velocity, whereas the gas flowing through the gas orifice near the periphery of the gas orifice will have the slowest velocity.
  • the difference in velocity can be substantial.
  • the fact that the gas flowing near the edge of a gas orifice has a much slower velocity than the gas flowing near the center of the gas orifice has a very detrimental effect on the pneumatic atomizer's ability to atomize the liquid film on the filming surface.
  • the speed of the gas flowing near the periphery of the gas orifice is almost the same as the velocity of the gas flowing through the center of the gas orifice by directing the gas supply conduit into a smooth converging surface or a duct of sufficient length that the gas flowing through it exits the duct with uniform velocity (i.e. a nozzle) having a downstream outlet that closely matches the shape and cross-sectional area of the gas orifice.
  • uniform velocity i.e. a nozzle
  • the nozzle's output immediately flows through a gas orifice disposed at the filming surface, and the velocity of the gas flowing near the periphery of the gas orifice will, quite advantageously, be almost identical to the velocity of the gas flowing through the center of the gas orifice.
  • the output liquid particles are not smaller in an instance in which a nozzle is used to cause the gas to pass directly through an orifice through the filming surface, because such arrangement has a drastic counter-productive effect on the liquid film on the filming surface.
  • One of the consequences of passing a gas through a sharp edge orifice js that the sharp edge causes the envelope of the fluid flow to constrict to a cross-sectional area less than the cross-sectional area of the orifice for some distance downstream in the fluid's flow. This reduction in cross-sectional area, is referred to in fluid dynamics texts as the "vena contracta.” When this phenomenon is present, the gas flowing through a sharp edged gas orifice will not come in contact with the sides of the gas orifice for some distance downstream.
  • the vena contracta we have found the deliberate creation of the vena contracta to be advantageous, and as a matter of fact, if the vena contracta is totally eliminated, (i.e. the sharp edge at the entrance of the gas orifice is not utilized) the gas flowing out of the gas orifice will come into contact with the liquid while the liquid is on the filming surface and cause such liquid to form a rolling wave or ridge on the filming surface around the perimeter of the gas orifice. As the liquid is no longer a thin film at the edge of the gas orifice, the liquid is, quite undesirably, entrained into the flowing gas in globs . The resulting particles are, most unfortunately, of large size.
  • the cross-sectional area and shape of the orifice through the filming surface is deliberately made slightly smaller than the cross-sectional area and shape of the outlet at the upstream end of the smooth sided gas supply nozzle, thereby creating a small, abrupt sharp edge projection or jut into the gas flow.
  • the gas does not come into touching contact with the liquid on the filming surface, and therefore does not have the opportunity to cause such liquid to form a rolling wave or ridge around the edge of the orifice, and to be entrained as large particles or globs into the flowing gas.
  • the only liquid the flowing gas comes into contact with is ribbons of liquid that have already left the filming surface to become entrained in the gas flow. Because the flowing gas thus does not come into contact with the liquid on the filming surface, the flowing gas will entrain the liquid only as thin ribbons of liquid which break into shreds which collapse into particles of exceedingly small size.
  • an atomizer device capable of reducing a fiowable liquid to an ultrafine dispersion of liquid particles in a propellant gas.
  • Our novel device comprises a body member having a gas nozzle defined by converging sidewalls or defined by a duct terminating in a first of two superposed smooth surfaces.
  • the first smooth surface is disposed in a substantially perpendicular relationship to the nozzle, and the second smooth surface is disposed in an abutting parallel relationship with the first smooth surface, with a very small spacing existing between the first and second surfaces.
  • a narrow edge of each of the surfaces is disposed adjacent the propellant gas flowing through the gas nozzle, with such narrow edge of the first surface jutting a short distance into the outlet of the gas nozzle.
  • the edge of the second surface is set back from the edge of the first surface, such that a filming surface is defined on the first surface, adjacent the gas nozzle.
  • Means are provided for directing a fiowable liquid under pressure into the space between the first and second surfaces, so as to cause such liquid to flow between the abutting surfaces, toward the flow of propellant gas through said nozzle, and emit as a thin film along said edge of the second surface.
  • This emitted liquid flows onto the filming surface of the first surface, and the propellant gas, when flowing through the nozzle, is caused by the jutting edge of the first surface to separate slightly away from said narrow edge of the first surface at the location of the filming surface.
  • Such slight gap or separation prevents the formation of a rolling wave or ridge of liquid on the filming surface, about the edge of the first surface, without inhibiting the flow of ribbons of such liquid from the filming surface into the propellant
  • the flow of the entrained liquid from the filming surface therefore takes the form of thin ribbons of liquid in the propellant gas flow, which ribbons of liquid break into shreds, which shreds collapse into particles of exceedingly small size.
  • Another aspect of inventions of this general nature involves the removal of relatively large liquid particles from a pneumatic atomizer' s output , by directing the output at a target, such as a sphere, located on the centerline of the atomizer's output stream, a short distance downstream from the atomizer.
  • the downstream gas flow must flow around such a target.
  • the smaller liquid particles present in the flowing gas which have a low momentum relative to their surface area, will flow with the gas around the target, whereas the larger liquid particles present in the gas, which particles have a high momentum relative to their surface area, are not able to flow around the target.
  • the larger liquid particles thus collide with the target and wet the target.
  • the principal object of the present invention is to provide an improved adjustable atomizer or pneumatic nebulizer used with low pressure propellant gas, that is capable of directly and uniformly generating an ultrafine stable fog of liquid particles, preferably having a maximum diameter of about 20 microns or. less, and having an average diameter of 10 microns, or ' less.
  • It is yet still another object of the present invention is to provide a pneumatic nebulizer embodiment in which all the liquid supplied to the liquid orifice means is nebulized and dispersed as a stable fog, i.e. there is no liquid run-off and no drippage of liquid from the orifice means or from other parts of the nebulizer.
  • Figure 1 is a view of a primary embodiment of our novel atomizer, partly in section to reveal internal construction, and with the cap removed to make it possible to view some of the important aspects of this embodiment of our invention;
  • Figure 2 is a cross sectional view of the throat portion of an illustrative device having inwardly tapering sidewalls, with the short arrows of approximately equal length being utilized to reveal the characteristics of the flow of air through the central orifice of such a device;
  • Figure 3 is a simplified showing similar to Figure
  • Figure 4 is a cross-sectional view of a throat section that represents some of the most important details of a basic device in accordance with our invention
  • Figure 5a is a cross-sectional view, to a larger scale, of the orifice portion of a device similar to that shown in Figure 2, but with Figure 5a revealing the deliberate use of a smooth contour at the location of the upper surface, upon which surface, liquid may be caused to flow;
  • Figure 5b is a cross-sectional view to the same large scale shown in Figure 5a, but with Figure 5b
  • nozzle with this jut or protuberance bringing about a distinct, highly desirable separation of the gas flow from the edge of the orifice;
  • Figure 6 is a cr o s s - s e c t i o n a 1 view of an embodiment in which a straight-sided nozzle rather than a converging nozzle is used;
  • Figure 7 is a view generally resembling Figure 1 in that it is a view partly in section of one of our atomizers, with the cap removed and fragmented in order to reveal the novel adjustable pintle we utilize in this particular embodiment;
  • Figure 8 is a cross-sectional view of the throat section of an embodiment in which an adjustable pintle in accordance with our invention is utilized.
  • Figure 9 is a fragmentary cross sectional view revealing the flow paths through the throat and around the upper portion of the pintle.
  • FIG. 1 With initial reference to Figure 1, it will there be seen that we have revealed a first embodiment 10 of our invention, involving a body member 12 having an internal passage 14 therethrough.
  • This internal passage 14 is configured to form a converging type nozzle 16 that accommodates the flow of air or some other suitable gas upwardly through the center of the member 12.
  • An alternative to- the utilization of a converging nozzle will be discussed hereinafter in conjunction with Figure 6.
  • the body member 12 may be secured, for example, to a conduit or supply duct 18 through which air or another gas under relatively low pressure may be supplied to the converging no ⁇ )e .16 of the body member 12.
  • the securing of the body member to the conduit or duct may be accomplished by the use of one or more lock screws 19.
  • Relatively fine external threads 22 encircle the upper exterior portion of the body member 12. These external threads 22 are designed to receive an internally threaded cap 24, whose internal threads 26 engage the threads 22 when the cap 24 is screwed onto the body 12.
  • cap 24 is shown in exploded relation to the body member 12 in Figure 1, and it will be noted that there is a central hole or aperture 40 in the cap 24 that is essentially in alignment with the internal passage 14 in the body 12, and the converging nozzle 16.
  • the smooth, symmetrically configured toroidally-shaped surface 36 is disposed on the body member 12, it may be regarded as a fixed surface, -nd it may also be identified hereinafter as the first surface.
  • the relationship of the peripheral contour of the orifice 30 to the generally columnar flow of propellant gas therethrough will be discussed at length hereinafter .
  • a steeply angled surface 42 extends entirely around the outer periphery of the toroidally-shaped surface 36, ith the upper edge of the angled surface 42 terminating at the outer periphery of the flat toroidal surface 36, and the lower edge of the angled surface 42 terminating near the upper edge of the external threads 22.
  • the second smooth, toroidally-shaped surface, 46 Around the upper interior portion of the cap 24 is what we call the second smooth, toroidally-shaped surface, 46, this latter surface being parallel to the first surface 36, and able to be brought into close contact therewith at such time as the cap 24 is screwed tightly onto the body member 12, with its threads 26 engaging the threads 22 on the body.
  • Figure 1 we show the first toroidally-shaped surface 36 and the second toroidally-shaped surface 46 in a spaced apart relationship. In reality, the surfaces 36 and 46 are in a very close, parallel relationship during operation of our device, typically spaced apart between .002 and .020 inches.
  • a radially inward flow of fluid takes place between the surfaces 36 and 46 when they have been brought closely together, so the' fact that the distance between the surfaces can be precisely changed by careful rotation of the cap 24 with respect to the body 12 is one of the important aspects of this invention.
  • e prefer tn use threads on the inside surface of the cap 24 that are sufficiently fine that one-half turn of the cap 24 changes the spacing between the surfaces 36 and 46 by only .020 inches.
  • FIG. 1 Also to be noted in Figure 1 is an inlet 54, disposed on the sidewall of the body member 12, by means of which the liquid to be injected or extruded into the gas flowing through -the internal passage 14 can be admitted to the body 12.
  • the inlet 54 is connected to an upwardly ascending passage 56 in the body 12, which passage terminates in an opening 58 located on the angled surface 42.
  • member 62 represents a fragmentary portion of a body member corresponding to body member 12 of Figure 1.
  • the member 62 has an internal passage 64 that becomes a converging nozzle 66, with aperture 70 being formed at the uppermost point of the body member 62.
  • Formed atop the member 62 is a first toroidal surface 72.
  • member 74 represents a fragmentary portion of a cap corresponding to cap 24 in Figure 1.
  • the member 74 has an under surface 76 corresponding to the undersurface 46 of the cap " 24. This may be regarded as the second toroidally shaped surface.
  • a central orifice or aperture 78 In the middle of the member 74 is a central orifice or aperture 78 , which is noticeably larger in diameter than the orifice 70.
  • the series of vertically pointing arrows appearing in Figure 2 may be regarded as representing the velocity and direction of the flowing gas. It should be noted that these arrows are all very nearly of identical length, for the outward gas flow is quite consistent across the orifice 70.
  • the gas flowing out of the orifice comes into contact with the liquid on surface 72 at the edge of aperture 70 and causes the liquid on the filming surface to form an undesirable rolling wave or ridge 79 on surface 72 around the perimeter of the orifice, as illustrated in Figure 2.
  • the liquid is no longer a thin film at the edge of such an orifice, the liquid is entrained in the flowing gas in globs.
  • the resulting particles are of large size.
  • FIG. 3 we show a preferred embodiment 80 involving a member 82 that represents a fragmentary portion of a body member corresponding to body member 12 of Figure 1.
  • the member 82 has an internal passage 84 that becomes a converging nozzle 86, with sharp edged orifice or aperture 90 being formed at the uppermost point of the body member 82, which may be regarded as the throat of the nozzle.
  • the orifice 90 is smaller in diameter than the corresponding orifice 70 in the embodiment of Figure 2, and as a matter of fact, the orifice 90 is located in a lip or projection 100 formed at the upper end or throat of the converging nozzle 86, extending for a short distance out into the column of gas flowing through the nozzle.
  • the upper surface of the lip or projection is coincident with the first toroidal surface 92 formed atop the member 82, and the lower surface of the lip represents a small, abrupt projection into the outlet of the gas nozzle 86.
  • member 94 represents a fragmentary portion of a cap corresponding to cap 24 in Figure 1.
  • the member 94 has an undersurface 96 corresponding to the undersurface 46 of the cap 24. This may be regarded as the second toroidally shaped surface.
  • a central orifice or aperture 98 In the middle of the member 94 is a central orifice or aperture 98 , which is noticeably larger in diameter than the orifice 90. It is to ' be understood the uncovered surface 92 between aperture 98 in member 94 and aperture 90 in surface .92 is the filming surface F.
  • the velocity of the gas flowing near the perimeter of the outlet of the nozzle 86 will be almost identical to the velocity of the gas flowing through the center of the outlet of the nozzle, and because the outlet's output immediately flows through the sharp edge orifice 90 which projects a very short distance into the outlet of the nozzle, the velocity of the gas flowing near the perimeter of the orifice is almost identical to the velocity of the gas flowing through the center of the orifice.
  • the provision of the sharp edge orifice 90 deflects the gas flow, as will be discussed at greater length hereinafter, but it does not to any consequential degree block the flow of gas through the orifice.
  • vena contracta One of the important consequences of passing a fluid through a sharp edge orifice, with resulting deflection of the flowing gas, is the formation of a vena contracta.
  • the cross-sectional area of the fluid's flow envelope will be less at the vena contracta than the cross-sectional area at the orifice, and also less than the area at a downstream location in the fluid's flow. Because of the foregoing, the fluid f lowing through the sharp edged orifice 90 will desirably not come into contact with the sides of the orifice for some distance.
  • the gas flowing through the orifice 90 will not be in contact with the edge of the orifice as the flow exits the downstream side of the orifice. Therefore, because the gas exiting the filming surface side of the orifice 90 is not in contact with the sides of the orifice, the gas does not come into contact with the liquid lying on the filming surface F. Rather, the only liquid the flowing gas comes into contact with is liquid that has left the filming surface F to become entrained in the flowing gas.
  • the flowing gas in the representation of our invention shown in Figure 3 advantageously does not cause the liquid on the filming surface to form a rolling wave or ridge around the edge of the orifice, resembling the showing of Figure 2, wherein the rolling wave or ridge 79 was depicted.
  • the cross-sectional area and shape of the orifice 90 through the filming surface F is slightly smaller than the cross-sectional area and shape of the outlet of the converging nozzle 86, thereby forming the aforementioned lip or jut 100 that we regard as consequential to our invention.
  • the small projecting edge or lip 100 of the filming surface F creates a small, abrupt projection into the gas flow, thereby overcoming the "rolling liquid wave" problem appearing at 79 on the filming surface in Figure 2, without significantly degrading the velocity of the gas flowing near the perimeter of the orifice through the filming surface.
  • the f ilming surface F On the upper or leeward side of the shelf-like member P is what we previously mentioned as being the f ilming surface F, which is the surface where an unencumbered fiowable liquid is extruded out between the smooth, parallel surfaces 92 and 96, and allowed to naturally spread out or film out until it contacts the propellant gas flowing through the converging nozzle 86. Because of this arrangement, the liquid residing on the filming surface F is entrained into the propellant gas from a location just beyond the innermost edge of the shelf P. We may also wish to call this innermost edge the entrainment edge, and this point will be dealt with shortly in greater detail, in connection with Figure 6.
  • the speed of the air or other gas through the nozzle 86 is desirably so great past the entrainment edge of the filming surface F as to remove the liquid extruded between the surfaces 92 and 96 as fast as it is extruded, thereby causing the liquid to remain the extremely thin film extruded between these surfaces as the liquid flows across filming surface F.
  • Figures 5a and 5b of the drawings have a definite relationship with Figure 2
  • Figure 5b has a definite relationship with Figure 3.
  • Figures 5a and 5b are shown to a slightly larger scale than the scale used in the execution of Figures 2 and 3, and it will also be noted that the reference numeral scheme associated with Figures 2 and 3 has been preserved in Figures 5a and 5b.
  • Figure 5a may be regarded as representing an orif ice 70 in which there is no jut or sharp edge projection into the column of gas that is flowing through the converging nozzle 66. Instead of a sharp edge orifice being utilized at this location, we show in Figure 5a the internal passage 64 terminating in a smooth, circumferential ly extending contour 71 at the location of the orifice 70.
  • a necessary ingredient of this embodiment of our invention is a jut or protrusion 110 along the lines of the jut or projection previously described, which of course is the component responsible for creating the flow separation discussed in conjunction with Figure 5b.
  • Figure 6 represents what may be regarded as a secondary nozzle embodiment, and it is not preferred over the converging nozzle except in limited circumstances, such as for use in a constricted space.
  • FIG. 7 Another important embodiment of our invention is depicted in Figure 7, wherein we have depicted a body member 112 showing a distinct similarity to body member 12 in Figure 1, which body member has a cap 124 having a distinct similarity to cap 24 in Figure 1.
  • body member 112 shows a distinct similarity to body member 12 in Figure 1
  • body member has a cap 124 having a distinct similarity to cap 24 in Figure 1.
  • FIG. 7 One distinct difference in the device of Figure 7, however, is the use of the central member 120 or pintle supported in the center of body 112, and therefore in the center of the passage 114 and the converging nozzle 116 inside the body 112.
  • This support of the pintle member 120 is brought about by the use of three or so legs 131 extending in a spoke-like manner from the internal sidewalls of the body 112, terminating in a hub 132, in the center of the passage 114. Some may prefer to call this a spider type support.
  • the hub 132 is preferably internally threaded to receive the compatibly threaded lower end 121 of the central member 120. In that way the user or operator can vary the relationship of pintle or impactor 120 to the apertures 130 and 140.
  • the important function of the pintle member 120 will be set forth at greater length hereinafter.
  • inlet 154 disposed on the sidewall of the body member 112, by means of which the -liquid to be injected or extruded into the gas flowing through the internal passage 114 can be admitted to the body 112.
  • the inlet 154 is -re ⁇
  • FIGs 8 and 9 we reveal other details of the configuration and utilization of the central member or pintle 120, and its relation to the other members of our novel device.
  • the pintle is generally of inverted conical shape, with its downstream end larger than its upstream end.
  • Figure 8.it will be noted that we have shown by the use of dashed lines, ⁇ n example of movement of the pintle member 120 along its centerline. The movements of the pintle automatically in accordance with gas flow will be the subject of one of our later inventions.
  • threads 121 are provided on the lower end of' the pintle, and as is obvious, we can establish the appropriate relationship of the pintle member to the gas flowing cut of the orifices of this figure by screwing it in, or alternatively, by unscrewing it from its relationship to the hub member 132.
  • FIG. 8 Also visible in Figure 8 are several pairs of arrows, which are utilized to call out the preferable distance X between the orifice and the mid sidewall of the pintle 120; the distance Y representative of the lateral extent or width of the projection 170 disposed around the edge of the pintle; the distance TL representative of the thickness of the projection 170; and the distance Z representative of the pintle being movable along the centerline of the device.
  • the effect of the pintle is to cause the larger particles to be captured and re-nebulized or reduced in size to a desirable extent.
  • the liquid particles that impact on the conical surface of the pintle 120 merge together, forming a liquid film on this conical surface.
  • the gas flow is deflected radially outwardly by the abrupt projection 170, which flow of gas we find to be particularly advantageous.
  • the liquid that gathers on the conical surface of pintle 120 and at the underside of projection 170 is swept by the gas flowing along and over pintle 120 and the underside of projection 170 to the outer edge of the underside of the projection 170, where the liquid is entrained in the flowing gas as small ribbons of liquid in the outwardly deflected flowing gas, which ribbons break up into small particles.
  • the impactor or pintle 120 is not needed in all applications and utilizations of our device, so for that reason it is desirable to construct it in the manner previously described, such that it can be unscrewed from the hub member 132 and entirely removed from the nozzle when the impactor is not needed.
  • the stem portion of the pintle member 120 is configured in such a way as to make it possible for the user to control and modulate the amount of air or other gas flowing through the passageway 114.
  • Such control is accomplished either by rotating the pintle to constrict the effective aperture, accomplished by bringing the impactor closer to the orifices 130 and 140, or else by rotating the body member in the opposite direction, so as to further remove the impactor from the vicinity of the orif ices , and to present less constriction to the flow of propellant gas through our device.
  • Figure 9 it will be observed that a gas eddy naturally occurs above filming surface F while our nozzle is in operation.
  • the jut or projection serves to create what may be regarded as a sharp edge orifice, and we have found that the abrupt jut or projection into the column of gas need not be so great as to interfere with the flow of gas through the nozzle. As a matter of fact, increasing the extent of the jut into the column of gas beyond a minimally sufficient amount is largely unproductive.
  • the criterion we follow in establishing the amount of the jut or projection into the throat of the nozzle is that it be of just sufficient extent or dimension as to cause just sufficient separation of the flow, in the manner depicted at 102 in Figure 5b of this case, to prevent the formation of a rolling wave or ridge or liquid at the edge of the filming surface.
  • the jut or projection should extend a short distance into the flowing column of gas, usually not less than .050 inch and not more than .150 inch, and preferably should extend approximately .090 inch into the column of gas.
  • the devices in accordance with this invention that are depicted in the drawings are shown as ⁇ components in which the filming surface circumscribes the column of gas flowing through the device, and such is the preferred embodiment, it is nevertheless to be understood that devices in accordance with the scope and spirit of this invention could include those in which the filming surface borders only a portion of the column of gas flowing through the device.
  • the propellant gas could be encased by a rectangular duct, with the filming surface located on only one side or sector of the duct, or with filming surfaces located on opposite sides or sectors of the duct.

Landscapes

  • Nozzles (AREA)

Abstract

Système d'atomiseur capable de réduire un liquide coulant, en une dispersion ultrafine de particules du liquide dans un gaz propulseur, comprenant un corps (12, 82, 112) ayant un ajutage à gaz (16, 86, 116) formé par des parois latérales se terminant dans la première des deux surfaces lisses superposées. Le liquide coulant est dirigé (58, 158) sous pression dans un espace étroit situé entre la première (36, 92, 136) et la seconde surface (46, 96, 146), vers l'écoulement de gaz propulseur traversant l'ajutage, et il sort sous forme d'une pellicule mince qui vient se poser sur une surface (F) de la première surface. L'écoulement de gaz propulseur traversant l'ajutage est provoqué par un bord (30, 90, 130), faisant saillie (100), de la première surface, qui doit être légèrement séparé du bord mince de la première surface au niveau de la surface (F) comportant la pellicule, cette petite séparation n'empêchant pas des rubans du liquide provenant de la surface (F) d'être entraînés dans le gaz propulseur, le liquide entraîné se fractionnant ensuite en particules extrêmement fines dans l'écoulement de gaz propulseur.
PCT/US1991/003154 1990-05-09 1991-05-07 Atomiseur reglable avec precision WO1991016991A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US52128090A 1990-05-09 1990-05-09
US521,280 1990-05-09

Publications (1)

Publication Number Publication Date
WO1991016991A1 true WO1991016991A1 (fr) 1991-11-14

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Country Link
WO (1) WO1991016991A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5337962A (en) * 1993-03-24 1994-08-16 Erb Elisha Pneumatic atomizer having improved flow paths for accomplishing the atomization of liquids
DE19507160A1 (de) * 1995-03-01 1996-09-05 Ppv Verwaltungs Ag Düse zur Vermischung und/oder Zerstäubung von Fluiden
WO1998028085A1 (fr) * 1996-12-24 1998-07-02 Pe Product Engineering Gmbh Dispositif de production d'aerosol
WO2003090935A1 (fr) 2002-04-26 2003-11-06 Willy Vogel Ag Dispositif pour produire un aerosol
RU2316369C1 (ru) * 2006-06-22 2008-02-10 Андрей Леонидович Душкин Устройство пожаротушения

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191201152A (en) * 1911-08-14 1912-06-06 Erik Anton Rundloef Improvements in or relating to Liquid Injection Devices for Internal Combustion Engines.
US1038804A (en) * 1910-05-09 1912-09-17 Joseph D Warren Carbureter.
US1436351A (en) * 1919-07-25 1922-11-21 Skinner Patent Holding Company Fuel nozzle
DE2147042A1 (de) * 1970-09-30 1972-04-06 Decafix Ltd Zerstäuber, insbesondere fur Heiz ölbrenner
US3993246A (en) * 1975-06-19 1976-11-23 Erb Elisha Nebulizer and method
US4161281A (en) * 1976-08-30 1979-07-17 Erb Elisha Pneumatic nebulizer and method
US4261511A (en) * 1978-08-07 1981-04-14 Erb Elisha Nebulizer and method
EP0244204A1 (fr) * 1986-04-28 1987-11-04 Western Packaging Systems Limited Buse d'atomisation à basse pression

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1038804A (en) * 1910-05-09 1912-09-17 Joseph D Warren Carbureter.
GB191201152A (en) * 1911-08-14 1912-06-06 Erik Anton Rundloef Improvements in or relating to Liquid Injection Devices for Internal Combustion Engines.
US1436351A (en) * 1919-07-25 1922-11-21 Skinner Patent Holding Company Fuel nozzle
DE2147042A1 (de) * 1970-09-30 1972-04-06 Decafix Ltd Zerstäuber, insbesondere fur Heiz ölbrenner
US3993246A (en) * 1975-06-19 1976-11-23 Erb Elisha Nebulizer and method
US4161281A (en) * 1976-08-30 1979-07-17 Erb Elisha Pneumatic nebulizer and method
US4261511A (en) * 1978-08-07 1981-04-14 Erb Elisha Nebulizer and method
EP0244204A1 (fr) * 1986-04-28 1987-11-04 Western Packaging Systems Limited Buse d'atomisation à basse pression

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5337962A (en) * 1993-03-24 1994-08-16 Erb Elisha Pneumatic atomizer having improved flow paths for accomplishing the atomization of liquids
DE19507160A1 (de) * 1995-03-01 1996-09-05 Ppv Verwaltungs Ag Düse zur Vermischung und/oder Zerstäubung von Fluiden
DE19507160C2 (de) * 1995-03-01 1998-02-26 Ppv Verwaltungs Ag Düse zur Vermischung und/oder Zerstäubung von Fluiden
WO1998028085A1 (fr) * 1996-12-24 1998-07-02 Pe Product Engineering Gmbh Dispositif de production d'aerosol
WO1998028086A1 (fr) * 1996-12-24 1998-07-02 Ebara Corporation Appareil generateur d'aerosol
KR100500084B1 (ko) * 1996-12-24 2005-07-12 가부시키가이샤 에바라 세이사꾸쇼 에어로졸 생성장치
WO2003090935A1 (fr) 2002-04-26 2003-11-06 Willy Vogel Ag Dispositif pour produire un aerosol
RU2316369C1 (ru) * 2006-06-22 2008-02-10 Андрей Леонидович Душкин Устройство пожаротушения

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