US1780738A - Spray nozzle - Google Patents

Description

Nov. 4, 1930. w Q'BEACH 1,780,738

SPRAY NOZZLE Filed March so, 1927 m a5 Z' 3] 27 15 16 17 z I z] IN VEN TOR. Maud/@- 351W 1 5 'aT TokN E Y Patented Nov. 4, 1930 PATENT OFFICE WILLARD C: BEACH, OFNEWARK, NEW JERSEY SPRAY NOZZLE Application filed March 30, 1927. Serial No. 179,428.

This invention relates to spray nozzles, by which term is included any device used in directing the efliuent of apparatus used in delivering a stream of fluid or semi-fluid 6 material in connection withair or gases under pressure whereby a fine i'et or spray is produced, and more particu arly to air brushes for distributing paints and like material.

Ordinary types of spray nozzles, whether 0f single central delivery or paired angular jets, are easily clogged with the paint or other semi-viscid material passed through them, necessitating frequent change of nozzles and consequent loss of production, to

16 the ex-tent that an experienced operator usually keeps a can of solvent at hand to soak out accumulations from dirty, plugged nozzles in order to have a convenient supply of clean nozzles for substitution.

It is therefore one of the objects'of this invention to provide a nozzle capable of performing all the functions of any known nozzle and which is substantially free from becoming clogged due to its peculiar construction. a a

A further feature is in the provision of a nozzle that distributes the material in an elongated rectangular field rather than a circle as is common and by the use of which 80 uneven distribution, as light and dark spots or voids, called holidays,-are avoided.

Another purpose is to produce a spray nozzle that is adjustable to suit the fluidity and nature of'the material, whether thick and viscid, or thin and free flowing, thus serving all reasonable requirements. These important advantages are accomplished by the novel design construction and combination of simple parts hereinafter described and shown in the annexed drawing, forming a material part of this disclosure, and in which Figure 1 is a side elevational view of a conventional type of air brush head, partiallyin section and illustrating the applicationof the invention.

Figure 2 is an enlarged front elevational view of the spray nozzle. 1

Figure 3 is a longitudinal sectional view taken 'on the center line thereof.

The paint gun or air brush head shown in Figure 1 is of a well known type consisting of a barrel 5 having a hiltor pistol grip .6 provided with an inlet 7 for compressed air, the same being delivered to the barrel by actuation of a valve controlled by a trigger 8.

The'valve is adjusted by a screw device.9 at the outer end ofthe barrel 5,, which may be supported partially or wholly by the ring 10, the air, passing through a filter 11 to a side extension containing a port 13 and then delivered to an annular chamber 12 in the front part of the barrel which is provided with external screw threads 21 as'shown.

The paint or other material to be sprayed c5 cnters'an orifice in a lug 14 extending downward from the barrel to pass into a threaded bore 15 in which is an adjustable guide 16 for a valve rod 17, controlled by the trigger 8.

Set in the forward end of the barrel is a '10 valve body 18 having a conical seat at the inms end of its recess 19 against which the valve 17 may engage thus controlling .a ls)trcgllight azgial passage 20 through the valve The body 18 is reduced in diameter near the end of the chamber 12 and the outer portion 22 of the valve body is tapered conically, terminating ina cylindrical tip 23. 7

With the exception of the valve body all of the described parts are of old and Well known construction, being given only for the purpose of illustrating the invention, a description of which now .follows:

Adjustably en aged on the barrel threads 21 is an externally-knurled hollow annulus 25 having. a reduced threaded forward porti0n@26 and containing a conical bore 27 lead- I ing to the interiorly threaded portion, the larger diameter of the bore being outward or away from the barrel and in open communication with the air chamber 12.

Screwed tight on the threads 26 is the smooth surfaced outer element 28 of the nozzle, the same containing an annular air equalizing chamber 29 open to the bore 27 and having an integrally closed front end wall 30 in which is formed a circular groove 31 of triangular cross section, the sharp angled bottom of which is deeper than the thickness of I the truncated cone 32, a substantially sharp k z le on the barrel.

edge 34 disposed essentially midway between the Wall of the bore 27 and outer surface of the conical element 22 of the valve body, the conicity of which and that of the bore 33 being alike so that a uniform annular space 35 exists between them.

At the apex of the conical bore 33 is a short ,eylindrical recess 36 acting as an atomizing chamber slightly larger than the valvevbody. tip 23 and leadingto't'hi's recess is an axial perforation orldischarge port 37 in register with the valve controlled passage 20 in the body 18.

At two opposite points in the element 2 are port perforations or fan jets 38 reaching through the outer wall of the angular recess 31 to theannular chamber 29, close to the wall 30, the diameter of these perforations being less than half their length, or thickness of the material throu h which they are formed.

It will now lie understood that the course of compressed air is through the chamber 12 to the conical bore 27, thence to be diverted by the edge 34 partially into the chamber 29 and out of the perforations 38, and partially into the s ace 35 to mix with the efliuent passing out of the passage 20 to be delivered outward of the nozzle through the perforation 3 It is also to be noted that the chamber 29 is more than double the capacity of the space 35 therefore delivering powerful air streams through the fan jet ports 38which, striking the efiluent from the central jet port 37, causes it to spread fan-wise in an effective I manner, this Jet being under approximately halfthe ressure of the jets38, which pressure can e varied by adjusting the noz- Due to the air pressure in the several'annular chambers, none of the material being sprayed is permitted to enter and by reason also of the pressure cloggin isavoidedQ From the foregoing it will be seen that a simple device for this purpose has been disclosed in the preferred form of its embodiment, but it is notdesir'ed to restrict the details to the exact instruction shown, it being obvious that changes, not involving the exercise of invention, may be made without conflicting with the scope of the appended claims.

Having thus described my invention, what "I claim as new and desire to secure by Letters Patent, is

. -1. spray nozzle comprising a two part incense body, one of said parts having means to engage the barrel of a spray gun and containcavity presenting a thin annular edge mid way the mentioned bevelled recess, a mixing chamber at the bottom of said cavity, a ort leading outwardly from the mixing cham er, an angularly walled annular recess in the face of the second part, and two ports disposed diametrically opposite to lead from the outer grail of the recess to the air equalizing chamer.

2. A spray nozzle adapted for attachment to a spray gun having a barrel and a hollow conical extension therebeyond, said nozzle comprising a hollow annulus adjustably threaded on the end of said barrel to receive cmnprlessed air therefrom, a cap fixed to the end of said annulus, said cap havin an air chamber,'a conical guard extending inner face of said cap into the chamber, said guard having a reversed conical bore spaced from the conical extension of the gun, the

- space and chamber receiving'air from the barrel, a mixing chamber at the apex of the conical bore, a port leading outwardly from the mixing chamber in register with the. axis of said hollpw conical extension, and a pair of inclined opposed ports leading through the face of said cap from-the compressed air chamber, said paired ports being disposedto intercept eflluent from the central ort.

cm the 4 3. In a spray nozzle, a two part ody, one

of said parts having means to engage the barrel 0 a spray gun and containing an annular-recessbevelledoutwardlyat its outer edge, the other part being connected to v.

the first part and containing an annular air equalizing chamber, a conical uard on the last named part entering the c amber, said guard containing'an inverted conical cavity,

and a mixing chamber at the bottom of said cavity, said mixing chamber having. a port 7 leading outwardly therefrom.

4. In a spray nozzle. av hollow annulus adapted to be threaded on the end of the barre] 0 a spray gun to receive compressed air therefrom, a cap fixed to the end ofsaid annulus, said cap having an air chamber, a conical guard extending fromtthe inner face'of said cap into the chamber, said guard having a reversed conical bore, and a mixing chamher at the apex of the conical bore, said mixing chamber having a port leading outwardly therefrom.

This specification signed and witnessed this 23rd day of March, 1927.

' WILLARD C. BEACH.

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