US2668084A

US2668084A - Atomizing device

Info

Publication number: US2668084A
Application number: US180051A
Authority: US
Inventors: Millard F Saxton
Original assignee: Engineered Products Co
Current assignee: Engineered Products Co
Priority date: 1950-08-17
Filing date: 1950-08-17
Publication date: 1954-02-02
Anticipated expiration: 1971-02-02

Description

Feb. 2, 1954 A M F SAXTON 2,668,084

IIIIIIIIIIIII CE discharg@ Patented Feb. 2, T1954 ff-ix UNITED STATES PATENT OFFICE A'roMIzrNG' DEvIcE y Millard F.' Saxton, Flint, Mich.; assignor to The Engineered Products Co..

poration of Michigan Flint; Mich a C01- vApplication August 17, 195o`,'seiis1` No, 180,051`

This invention relates to an atomizing device for converting liquids under pressure into a nely divided state such as for igniting, homogenizing or aerating the liquid. A V

It is an object of this invention to produce an atomizing device which is economical to manufacture and which, at the saine time, produces a uniformly ne spray.

It is a further object of this invention to produce an atomizing device which is designed such that it can be calibrated very readily to produce a--s in Fig. 1.

Fig. 4 is a sectional view of the orice plate taken substantially along lines 4-4 in Fig. 6.

Fig. 5 is a sectional view taken at right angles to the axis Yof the grooves in the retainer plate along lines 5 5 in Fig. 4.

Fig. 6 is a horizontal sectional view through the retainer plate taken along lines 6 6 in Fig. 4.

Fig. 7 is a fragmentary perspective view'of the retainer plate.

The atomizing device of this invention generally comprises abody member in the form of a housing I0 which is externally threaded at one end as at I2 for connection with a source of liquid under pressure to be atomized. Housing I0 is internally bored as at I4, the bore being ensmalled at one end to provide a shoulder I6 and an opening I8 at the end of housing I4 opposite the threaded end I2. The bore I4 of housing I0 is internally threaded as at 20 to receive a threaded retainer 22. Retainer 22 is in the form ofla hollow plug having a central inlet passage 24 .forined Aas a blind holen in the threaded end of the retainer and is provided with a, plurality of transversely extending ports. 26 which communicate With the passage 24 to provide outlet ports. The inner end of retainer 22 has an external diameter less than the diameter of bore I4 such as to provide a circumferential passage, 28 between the retainer and the housing. I0 into which passage the ports 26 9 claims. (c1. 29e-"120).

Between the end'face 30 of retainer 22 and `shoulder I6 of housing IU there is positioned an orifice plate 32 which is grcoved circumferentiallyon one face as at 34v to interiit with shoulder I6. Groove 34 forms a reduced end portion 36 `which projects through opening I8 in housing I0. Plate 32 is dimensioned such as 'to have a rather snug iit in bore I4 and is held in fixed position within housing Ill by retainer 22 which bears with its end fa'ce 30 against the inner `flat face 38 of the retainer. The outer face 40 of plate 32 is provided with a central oriiice'4I of cylindrical form which is dimensioned to give a predetermined rate of liquid ow'.

'In the opposite face 38' of plate 32 there is formed'a conical opening 42 which communicates i at its reduced end with the orilice 4I. 'In face 38 of plate 32 there is also formed a plurality of slots 44 which extend from the outer periphery of the plate to the conical opening 42 in adirection generally tangential ofopening 42. As is best illustrated in Figs. 5 and 7, slots 44 are triangular in cross section and the angle a between the side `walls of slots 44 is preferablyequal to the apex angle b of opening42. In the form of the invention shown, three slots 44 are shown. The number of slots provided and their size, of course, depends upon the ow required through the nozzle. Oneof the importantfeatures of my invention resides vin the design of the slots 44. It will be observed that these slots are inclined to the inner face 33 of plate 32 or, in vother words, the root 46 of each slot forms an angle c with the face 38. The angle c is determined such that slots 44 may be cut with a tool which moves in' an unconned manner transversely across the face 38 of plate 32 without cutting into or nicking the opposite edge of opening 42. This is clearly illustrated in Fig. 4 where it will be seen that the root 46 of each slot extends along the line which clears the face 38 of plate 32 on the side of opening 42 which is opposite each groove 44.

With the parts assembled in the manner illustrated in Fig. 1, it will be noted that grooves 44 provide channels which connect the circumferential passage 28 with conicalopening 42 and that the end face 30 of retainer '22 closes the open end of opening 42 so as to provide a conical chamber. Channels 44 are of vtriangular cross section which reduces in area in a direction towards the conical chamber formed by opening 42 and end face 38 of retainer 22.

To atomize the liquid the nozzle is connected as by the threaded portion I2 with a 'source of liquid under pressure so that liquid of the desired pressure is supplied to the opened or rear end of housing l0. The liquid ows into the central inlet opening 24 and is then conducted by the ports 26 to the circumferential passage 28 from which passage the liquid news into slots 44 at an entry point adjacent the outer ends of the slots. The liquid then ows through the triangular slots into the.chamber gformedby opening 42 and Iout of the discharge end of the nozzle through the orice 4|. It will be noted that, because of the inclination of slots 44, the liquid tends to impinge against the end face r,31h-,of ,retainer 22 and thus a 4desired turbulence of 'the liquid is obtained. Due stoithe 'generally rtangential entry of the liquid into thereonicalechamber formed by opening 42, the liquid rotates in this chamber, gaining velocityaasvit spjnsgtdvvards the reduced end of this chamber and" orifice '4L As the liquid leaves the orifice it stopsrspinning and is thrown out in small microscopic droplets iormingiasholloweconcalsnrey- AS .fhastbeen :stated previous-1r, sletsfi Meere :de- -sisned isuch that frthey i candle cut :hv :a Simple :machining:Qnerationzsuchasrby: mtatingfmllsing cutter. -ilhsiform .ofelot is Ialso desirable -i-from the ;ste ndn0int rofiealibratcn yser the rnoz- L:.zle. Il havefgfourid thatewithzainezzle. constructed as :described herein calibration .greatly simpli- .zfiredhecauseitheiflowfthmuehetheenozzlesatia .con-

r-.stant :pressure be either increased .or fde- :3.o

creased with:no-fappreciablechange inspraymngle ihygsmlly lappingeont; rincer-4 iswhen itiis desired -utoiinerease .the floweaud-:hv-.leppinsjace 3.8 fof plate 32 when it is desiredtordecreasethe flow.

Ehe :reason amy :Irry nozzle can fbe calibrated :thieme-nner iwill heeappreciatedifrom-.a C011- isideration of i the riolloirinsxmathematcal requaztions:

The spray :ansie-fof. amozzleiofrthsztvpeds determinentby.therfollovrinsfeeuationI 'I'Pf -D. changesto A n (11) fle-Aim?) :thus effecting-a decreasef -inI'L.

Howeverpsince Af M im :then

`4 and therefore M is also decreased. Since the upper and lower factors in the spray angle equation stated above both change in the same 4direc-- tion, there is little change in spray angle when the rate of flow is increased by enlarging the orifice.

When it is desired to decrease the flow, the back surface of plate 32 is lapped off. Since grooves 41% are of triangular shape, thefreduotion in area of these grooves is proportional to the square of the amount removed from surface 38.

-At. thesame time, the diameter of the spin chamher formed by opening 42 is reduced as a straight `:linefunctional because of its conical shape. .'15,

Since R e L-e,

theniitgfollows that and L is reduced. However, since A1- MTA-0 then M2 :Y Ai'- vand M isl also reduced. "Therefore .the equation Here again the upper and lower factors :,.Qfithe equation .change in fthe fsamedirection :andthe spray angle tends to remain substantially the `sarne when theowris decreased loydappingithe back face 33 of plate S2.

YIt Will-thusbessen-,that V1;-have provided an improved atomizing f device, the f construction @of .whichis advantageousinot only from the stand- .-.lJ.0int yofrnanufacture but ralso frorn=1the- -stanj d point of operation and calibration. It will vbe :readily appreciated .that the operation iof Iforman E `ing `.the :slots .e134 :by e a tool -suoh .as .a rotating ...milling .cutter is Ia Very vfast machining Aoperation as compared to the conventionalmanner of forming a slotin ;a .nozzle .plate by. coining or by .emilling .toastop whichwould be necessary ,where -zunconiined .transverse rrnovement .of :the cuttng .tool .is not possible. Another advantage `of my Aclesignfis that the oriiice plate 4may ihe Ymarchinedfrom niaterialsawhichfare extremely hard, -;-suoh.as sapphire or tungsten carbide.

gIt willhernoted that. allof the sections of the `,orilcemlate are well ,bolstered `so .that the-use of a brittle ymaterial is not ,objectionable The .machining of .the `retainer platecan, Yof course, .be performed .by commercially recognized .methods of the jewelA processingl industry.

.The operating` characteristics ofmy .nozzle are also-superior to ,conventional nozzles. Frictional ,losses .are maintained at aminimum-because of ,theV tapered, slots as .compared withrslots .of 4.uni-

forrn cross section. .In addition, ,the orificeplate f5 to the fluid as it advances toward the orifice.

I claim:

1. In an atomizing device, a housing, a plate in said housing, said plate having a passageway extending therethrough, said passageway being of conical shape at one end and being ensmalled to form a cylindrical orifice at the other end, the face of said plate adjacent the conical portion of said passageway being substantially flat and having a plurality of slots therein extending from the periphery of said flat face at the outer end to the conical portion of said passageway at an angle inclined toward said face of said plate, and means within Said housing closing the conical end portion of said passageway and forming passage means for admitting liquid to said slots adjacent the outer end thereof.

2. In an atomizing device, a housing, a plate in said housing, said plate having a passageway extending therethrough, said passageway being of conical shape at one end and being ensmalled to form a cylindrical orice at the other end, the face of said plate adjacent the conical portion of said passageway being substantially fiat and having a plurality of triangular slots therein extending from the periphery of said flat face at the outer end to the conical portion of said passageway at an angle inclined toward said face of said plate, and means within said housing presenting a wall portion closing the conical end portion of said passageway and forming passage means for admitting liquid to said slots adjacent the outer end thereof, said slots being inclined toward said wall at their inner ends whereby the liquid owing therethrough is caused to impinge against said wall portion as the liquid enters said conical passageway.

3. In a nozzle for atomizing fuel, a housing, a plate in said housing having an orifice in one face thereof for discharging liquid as a spray from said housing, said plate having a conical concavity in its opposite face communicating at its reduced end with said orifice, said opposite face having a plurality of slots therein extending from the periphery thereof to said conical concavity, said slots extending generally tangentially of said conical concavity with the roots of said slots inclined toward said opposite face in the direction of said concavity, and meansV within said housing presenting a wall closing the enlarged end portion of said concavity at said opposite face and providing passage means for admitting liquid to said slots adjacent the outer end thereof, the roots of said slots being inclined toward said wall at the discharge end of the slots whereby the liquid flowing through said slots and into said conical concavity is caused to impinge against said wall.

4. The combination set forth in claim 3 wherein the slots are of triangular cross section and the angle included between the side walls of said slots is substantially equal to the apex angle of said concavity.

5. The combination set forth in claim 3 wherein said opposite face of said plate is iiat and wherein said last mentioned means cornprises a plug member threadedly engaged with said housing and having an end face contacting said opposite face of said plate.

6. The combination set forth in claim 5 wherein said end face of said plug is substantially flat and is smaller in diameter than said opposite face of said plate, said plug being hollow and having passageways extending from said hollow portion through the side wall thereof adjacent said end face.

7. The combination set forth in claim 3 wherein the root of said slots is inclined to said opposite face of said plate such that the slots may be formed with a cutting tool of unconned lateral movement without cutting into said opposite face at a point beyond the intersection of said slots with said conical concavity.

8. The combination set forth in claim 3 wherein the root of each slot is inclined to said opposite face of said plate such that a line extended through said root at the discharge end of said slot passes through the enlarged end of said conical concavity without intersecting the side wall portion of said concavity Vopposite the discharge end of said slot.

9. An orifice plate for an atomizing device comprising a body portion having a passageway extending therethrough to opposite end faces of the plate, said passageway being of conical shape at one end and ensmalled to form a cylindrical oriiice at the other end, the face of said plate adjacent said conical end of said passageway being substantially flat and having a plurality of slots therein extending from the periphery thereof to the conical portion of said passageway, said slots extending generally in a direction tangentially of said conical end of said passageway and extending along a line inclined toward said last mentioned face of said plate, the angle of inclination being such that the root of each slot when extended passes through the enlarged end of said conical portion of said passageway without intersecting the side wall portion of said passageway opposite the discharge end of each slot.

MILLARD F. SAXTON.

Great Britain Mar. 13,'1931