US2612406A

US2612406A - Atomizing nozzle

Info

Publication number: US2612406A
Authority: US
Inventors: Kurata Fred
Original assignee: KASK TECHNICAL CORP
Current assignee: KASK TECHNICAL Corp
Priority date: 1948-08-12
Filing date: 1948-08-12
Publication date: 1952-09-30
Anticipated expiration: 1969-09-30

Description

Sept. 30, 1952 F. KURATA 2,612,406

ATOMIZING NOZZLE Filed Aug. 12, 1948 2 SHEETS SHEET 1 Laterally extending terminal portion 3 of spring member contains an aperture 9 in direct alignment with the axis of orifice 7 and chamber 6 of the nozzle. A valve member ID, preferably having a conically-shaped terminal or end portion I I and an elongated stem portion l2, extends throughjape'rture 3 and fits tightly therein. Terminal portion of valve member I may be of spherical shape without departing from the scope of this invention.

Abracket I3 is rigidly fastened tothe spring member adjacent terminal portion 3 by bolts M or any other suitable means and a portion l5 thereof extends laterally over the valve stem l2. The'laterally extending portion I5 of the bracket l3 contains an aperture IS in direct axial alignment with aperture 9 and discharge orifice 1. The aperture l6 receives an adjusting screw I! which may be maintained in any desired position by a lock nut 8. The adjusting screw conjf'tacts the end of the valve stem l2 and seats the ironically-shaped endportion l upon the discharge'or'ifice with any desired degree of force. When in position, the conical terminal portion H of valve member I0 is seated in cylindrical orifice 1 to form a continuous line or knife edge'contact between the'surface. of terminal portion and'the outer edge of the mouth of orifice'L, When seated and when-in vibration,

valve member I0 is axially aligned with, and

I perpendicular to the plane formed by the mouth -"of,.orifi'ce l6.

Inorder to secure a rapid vibration of valve member |0 upon its seat in the outlet orifice I, 1 a resonant system is set up in which the mass of-thespring member and elements attached therewith are balancedagainst the resiliency of thespring so that the system will vibrate freely inalongitudinal direction when as may be demonstrated, for example, by striking it a sharp blow. In actual operation the size of orifice 1,

- Lthestrength of spring and the mass of spring j and valve member Ill are so .co-related to one ;another that the, passage of liquid under pres- .-.sure;through the nozzle orifice l supplies a force in correct phase relationship to the resonant System so that. the same-is maintained in forced vibration. The rapid vibration of the valve member ID upon the discharge orifice l breaks up the liquid into a spray-likefo'rm.

Q. ;.In general the greater the mass of the vibratory part, thelower will be the frequency of vibration, and the greater the spring force, the higher ,will be the frequency of vibration. The

frequency of vibration will also tend to increase withan increase of liquid pressure at the source, but, this factor is, usually'not as important as the mass of the spring and the parts associated 1 therewith and the spring tension.

Thus it is seen that byvarying and balancingthef'co-"aoting forces, the operable limits of thedevice may be widely changed and any desired'degree' of atomization of the liquid can be procured. 'fF'or most practical purposes, the

' "frequency of vibration will be maintainedwithin the'audio "range, and, forexample, frequencies of 60 to several thousand cycles per second may T 'be cited.

i f'Figure 3 of the drawings illustrates a modificationf in which the rapid vibration of the valve member is produced by a helical spring. Ac- 7 fz cordingfto Figure-'3, numeral 20 designates a body portion ofanydesired shape, preferably 'cylindrica'lf having a chamber 2| therein and a threaded end section 24'; A discharge orifice or aperture 23. passes through end section 24 in open communication with internal chamber 2| Chamber 2| and aperture 23 are preferably cylinders of circular cross-section and are axially aligned. In the preferred embodiment of the device shown in Figure 3, chamber 2| narrows by the means of a conical or beveled section 22 to aperture, 23 in order tominimize frictional threaded is screwed on to threaded end section the outer edge of discharge orifice 23.

. forated disk 31.

24 of body portion 20. A valve member 21 having a valve head 28 is located centrally within chamber 2| with the valve head 28 seated on That portion of valve head 28 which seats in orifice 23 is preferably conical as indicated by numeral 29. Valve head 28 may be spherically shaped without departing from the scope of this invention. I

An important feature of the nozzle is the seating of the conically-shaped valve head 28 onthe outer edge of the mouth of orifice 23 to make a line contact or a knife edge contact. Suchcontact is in contrast to surface contact which would result if the outer edge of orifice 23had conically-shaped sides parallel to sides '29 of valve head 28. Other important features of orifice 23 and valve head 28 will'be discussed hereinafter.

Valve member 21 contains an end section 3| which extends from valve head. 28 as shown. A cylindrical-helical spring 32. surrounds end section 3| and seats on a'flanged washer. 30 on the shoulder of valve head 28. The other end of spring 32 fits in recess 33 and presses against housing or cap 26. In this manner, valve member 21 is urged towards orifice 23 andv valve head 28 is seated therein. The housing or cap 26 contains a plurality of openings 34 forthe emission of the spray or fog from the cap.

Chamber 2| is recessed at 36 to receive a per- Member 31 has an opening 38 centrally located. therein through which valve stem 21 is inserted. The clearance between the walls of opening 38' and valve stem 21 is sumcient to allow free movement of the valve member 27 ina longitudinal direction while restricting its transverse movement. Chamber 2|", orifice 23, valve stem 21, and opening 38 are axially aligned.

The end of body portion 20 opposite orifice 23 is open and internally threaded to receive a plug I 39. Plug 39 is screwed into threaded chamber 2| to hold guide member 36 in a fixed position by means of a conventional gasket 4|. Plug 39 is also internally threaded to receive a threaded conduit 42 transmitting liquid under pressure to chamber 2|.

In operation, the size of'the outlet orifice 23, the strength of the spring 32 and the mass of the spring 32 and valve member 2'! are so corelated to one another and to a given liquid pressure within chamber 2| that valve member 2'! is maintained in forced vibration as 'part of a resonant system. Liquid passes through orifice 23 and is transformed into a fine spray or fog which passes from inside cap 26"through openings, such as openings 34, tothe surrounding area. Openings 34 may b angularl 1- l'ecting inch'gage'. Curve B represents the results. of the P 1 most efficient commercial nozzle at 3000 pound per square inch gage. The curves of Figure 4 show that at Q pounds per square inch gage 64 per cent of the brine sprayed remained in suspension after spraying for one minute with the vibrating type nozzle of this invention and lessthan 11 per cent of the'brine sprayed remained in suspension after spraying for one minute with the most efiicient commercial nozzle. "At 5000 pounds persquare inch gage with the-vibrating type nozzle 93'per centofthebrine sprayed remained in suspension after spraying for one minute. After ten minutes' of'settling at 3000 pounds per square inch gage, '27 per cent of the brine sprayed by the vibrating type nozzle was still in suspension as compared to 4 per cent of the brine sprayed by the most efiicient commercial nozzle. Figure 4, gives a measurement of the amount ofv liquid atomized by. the nozzles compared and indirectly a comparison of the fineness of the spray particles,

Various alterations and modifications of the nozzles illustrated, such as the size, shape, and the type of spring,. may become apparent to those skilled in the art without departing from the scope of the invention. Various uses of the nozzle and its principle of operation are contemplated such as for the use in'humidification, emulsification, milk spraying, spray drying, fuel 'in its normal span of movement in a substantially longitudinal direction'along the axis of said orifice and having a closed'terminal portion-terminating adj acent said'orifice' and seated 'onthe injection, spray painting, powder metallurgy, surface cooling, fire extinguishing, distillation, etc. The vibrating principle of the nozzle in atomizing liquids has its obvious application as an integral part of equipment and appliances, such as, oil burners, internal combustion engines, fire extinguishers, etc. In any of these instances the nozzle portion of the apparatus is defined by the various associated parts necessary to produce a vibratingaction ofa valve member, the result of which vibrating action atomizes the liquid.

It is understood that the essence of the present invention is the .employment of a vibrating member for atomizing of a liquid, and it is realized that there are many available ways other than those specifically disclosed herein for bringing about the desired results. v

Having described my invention, I claim:

1. An atomizing nozzle comprising a body portion having achamber within said body portion; a conduit supplying liquid under pressure to said chamber; an outlet orifice of smaller dimensions communicating with said chamber; a bow spring rigidly attached to said body portion, said bow spring extending over said outlet orifice, said bow spring having an aperture therethrough aligned with said outlet orifice; a valve member extending through said aperture and seating in said outlet orifice; and an adjusting screw urging said valve member towards said outlet orifice associated with a bracket rigidly attached to said bow spring, the arrangement being such that said valve member is maintained in forced rapid vibration bythe pressure of said liquid acting on a resonant system comprising said spring and parts associated therewith. I

2. An atomizing nozzle comprising in combination a bodyportion having a chamber within said body portion and a. stationary outlet orifice having an edged seat and .of substantially smaller cross-sectional dimension than said chamber, a movable valve member adapted to freely move edged seat of said outlet orifice, said'terminal portion having a maximum diameter not greater than 1 times the diameter ofthe orifice .and

an apex angle between about 60 and about 150 at its point of, seating on said orificepand a spring urging said movable-valve member firmly into the seat of said outletnorifice. 1

3. An atomizing nozzle comprising in combination a body portion. having a chamber .within said body portion and-a stationary outlet-orifice having an edged seat and of substantially smaller cross-sectional dimension than said chamber, a movable valve member adapted to freely move in its normal span of movement-in a substantially longitudinal direction along the axis ofsaid orifice and having a closed terminal portion-seated on the edged seat of i said outlet orifice,"- said terminal portion having a maximum diameter not greater than 1% times the diameter of the orifice and an apex angle between about 60 and about 150 at its point of seating on said orifice, and a U-shaped bow spring having substantially parallel legs urging said moveable valve member firmly into the seat of said outlet orifice.

' 4. An atomizing nozzle comprising in combination a body portion having a chamber within said body portion and a stationary outlet orifice having an edged seat, a moveable valve member adapted to freely move in a direction substantially perpendicular to said outlet orifice and having a closed terminal portion ofa diameter not greater than about 3 2 of an inch greater than the diameter of said orifice and seated on the edged seat of said outlet orifice and a spring positioned externally ofsaid chamber of said body portion urging said moveable valve member towards saidoutlet orifice.

6. An atomizing nozzle comprising in combination a body portion having a chamber within said body portion, a stationary cylindrical outlet orifice and a converging passageway in the form of a to cone leading from said chamber to said orifice, said orificebeing between'about 1 and A; of an inch in length and between about ,4 and about inch in diameter and smaller in diameter than any preceding passageway-of said body portion, a moveable valve member adapted to freely vibrate in a. direction substantially'perpendicular to said orifice and having a closed terminal portion in the form of a cone having an apex angle between about 60 and about and a diameter of not more than a: of an inch larger than the diameter of said. outlet? orifice seated in said cylindrical :outlet orifice and a spring urging said moveable valve member towards said orifice. J

7. An atomizing nozzle comprising in combination a body portion having a chamber within said body portion, a stationary cylindrical outlet orifice and a converging passageway in the form of said orifice being between about "1 6 and /4 of an inch in length and between about 4 and about /2 inch in diameter and smaller in diameter than any preceding passageway of said body portion, a moveable valve member adapted to freely move in a direction substantially perpendicular to said orifice and having a closed terminal portion in the form of a cone having an apex angle between about 60 and about 150 and a diameter of not more than 4 5 of an inch larger than the diameter of said outlet orifice seated in said cylindrical outlet orifice and a spring urging said moveable valve member towards said orifice.

8. In an atomizing nozzle containing a closed moveable valve member seated on the edge of an orifice of said nozzle by the pressure of a spring, the method for improving the atomization of said nozzle which comprises supplying to said nozzle a liquid at a substantially constant pressure between about 100 and about 6000 pounds per square inch gage, vibrating aid move able valve member in a direction substantially perpendicular to the mouth of said Orifice at a frequency of at least 60 cycles per second by using only the force supplied by the liquid under substantially constant pressure, and passing liquid through said orifice whereby the liquid is atomized by the vibration of the moveable valve member.

9. In an atomizing nozzle containing a closed moveable valve member seated on the edge of a cylindrical outlet orifice of said nozzle by the pressure of a spring, said valve member having a valve head not greater than 1 times the di- 10 ameter of the cylindrical outlet orifice, the methed for atomizing a liquid by said nozzle which comprises supplying to said nozzle a liquid at a substantially constant pressure between about 2000 and about 6000 pounds per square inch gage, vibrating said moveable valve member in a direction substantially perpendicular to the mouth of said orifice at a frequency of at least cycles per second by using only the force supplied by the liquid under substantially constant pressure, and passing liquid through said orifice whereby the liquid is atomized by the vibration of the moveable valve member.

FRED KURATA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 943,780 Hughes Dec. 21, 1909 1,088,318 Bicakly Feb. 24, 1914 1,595,625 Scott Aug. 10, 1926 1,609,578 Scott Dec. 7, 1926 1,893,457 Tartrais Jan. 3, 1933 2,119,966 Scott June 7, 1938 2,172,556 Edwards Sept. 12, 1939 2,272,094 Murphy Feb. 3,.1942 2,422,059 Wilber June 10, 1947 FOREIGN PATENTS Number Country Date 16,317 Great Britain Aug. 1, 1908 of 1908