US2626188A - Spray gun - Google Patents

Description

Jan. 20, 1953 w. DALRYMPLE SPRAY GUN INVENTOR. :WILLIAM P. DALRYM PLE ATTORNEYS W. P. DALRYMPLE SPRAY GUN 2 SHEETS-SHEET 2 Original Filed March 14, 1947 s mi @ww/Mb v mm mm k wm WILLIAM P. DALRYMFLE BY awo ATTORNEYS Patented Jan. 20, 14953 to American Brake Shoe Company, Wilmington, Del., a corporation of Delaware Original application March 14, `1947, Serial No. 734,819. Divided and this application February 17,' 1949, Serial No. 76,873

4 Claims.

This invention relates to spraying devices and more particularly to spray guns of the type' adapted to spray a coating material such as paint, or the like, in a finely divided and controlled spray.

It is the primary object of my invention to afford a novel spray gun which is relatively light in weight, can be easily handled and operated, and wherein the regulating and control valves, although being readily accessible to the operator, are in close fitting alignment with the gun so that they do not protrude therefrom in an objectionable manner and, therefore, are protected from being accidentally struck vand thereby Yunintentionally dislodged from their desired settings during normal operation of the gun.

A further object of my invention is to construct a spray gun wherein a master control valve is embodied in the body of the gun wherein arelatively large valve can be effectively used, and which valve is operable to efficiently regulate the pressure of the air flowing to the nozzle to Values within the desired limits. A

A further object of my invention is to construct a spray gun wherein the adjusting mechanism for setting the needle valve controlling the flow of air through the discharge nozzle is readily accessible to the operator during' operation of the gun, and is positioned relatively close to the body of the gun and blends into the outlines thereof so as not to project objectionable amount therefrom.

An object ancillary to the foregoing is to construct a spray gun having needle valve adjusting mechanism of the aforementioned character which is in substantially the same proximity to the body of the gun in all positions of adjustment, and does not move in and out relative to the body of the gun during adjustment of the needle valve.

YetA another object of my invention is to construct a spray gun which may easily be disassembled and assembled so that the gun may be quickly and readily cleaned both exteriorly and interiorly. f

Yet a further object of my invention is to construct a spray gun which is simple and positive in operation and which canbe economically manufactured commercially and will give long eicient service. o. 1 YOther and further object of the present invention will be VVapparent from the following description and claims and are illustrated in the accompanying drawings which, by Way of illustration, show a, preferred embodiment of the present invention andthe principles thereof and what I now consider to be the best mode in which `I have contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structuralv changes may be made as .desired by those skilled in the art without departing from the present invention and the pur-view of the appended claims.

Y VIn the drawings: y

'A Fig. 1y is a sectional view showing a spray gun embodying the principles of my invention, certain parts thereof being shown in elevation;

Fig. 2 is a detail sectional yview taken substantially on the line 2-2 in Fig. 1.

Fig. 3 vis a detail sectional view, similar to Fig. 2, but showing the master control valve in a different regulating position.

Fig. 4 is an enlarged sectional view somewhat similar to Fig. 1;

Fig. 5 is a detail end elevational View looking the direction of the arrows 5-5 shown-in Fig. 4;

fFig. 6v is a detail side elevational View of the mechanism shown in Fig. 5;

Fig." 7 is a detail sectional view taken substantially along the lines '1 -1 in Fig. 6;

Fig. 8 is a detail sectional view taken substantiallyalong the line 8 8 in Fig. 6; and v 'Fig. 9 is a detail sectional view taken substantially along the line 9-9 in Fig. 6.

General construction of the spray gun The gun 20 shown in the accompanying drawingsY embodies a body 22 having a handle 24 projecting from one end portion thereof and a nozzle head 26 attached to the other end thereof. The nozzle head 26 comprises an air discharge nozzle 28 and a liquid discharge nozzle 313,` both nozzles being attached to a coupling memberV 32 by a collar 34, the coupling member 32 being attached to the body 22 in a manner to be described hereinafter.

Air enters the gun 20 through a passage 35 in the handle 24 and flows through the handle 24, the body 22, and out through the nozzle head 26. Y

When assembled in the manner shown in Fig. 1.wherein my Vnovel gun 20 is connected to a paint container 31 which isnot pressurized, the

aspirating eiect of the air being discharged from the nozzle head 26 is eiTective to cause coating materials, such as paint, to be drawn up from a container 31 through a pipe 39 into the nozzle head 26 and to be discharged from the nozzle head 26.` However, it will be understood that this assembly is shown only for the purpose of illustration of my invention and not by way of limitation, and that my gun 2U may be equally as eiectively connected to a paint supply wherefrom paint is fed to the gun under pressure. nozzle head 26 intimately mixes with the stream of air being discharged therefrom and is thereby blown from the gun 20 in a controlled spray.

One portion of the air 'discharged from the nozzle head 26 is discharged from a central air orice 4|; another portion of the air is discharged through orices 43 and 44 formed in wings 46 and 41, respectively, on the outer nozzle 23 and acts to modify the stream of air emitted from the central orice 4| and yet another portion of the air discharged from the nozzle head 26 is directed against the outer face of the wings 46 and 41, transversely to the nozzle openings 43 and 44 therein, and acts to keep the wings free of paint which otherwise might accumulate thereon.

Specific construction of the spray gun The air passage 3'5 extends from the free end 49 of the handle 24 substantially longitudinally into the handle 24 and terminates at its inner end portion in an air-inlet valve chamber 5|. The outer end portion of the air passage 35 is tapped to provide threads 52 therein into which a suitable threaded coupling member may be screwed, to attach an air hose or the like to the gun 20.

A valve housing 54 having a longitudinally extending opening 51 and four transversely extending openings 58a, 58h, 58e, and 58d, Figs. 1l

and l0, is screwed into the valve chamber 5| wherein it seats against a shoulder 60 formed therein. An air valve 62 having a spindle 63 attached thereto is mounted in the valve chamber 5| and is positioned to seat against a valve seat 65 formed on the inner end portion of the valve housing 54 adjacent to the inner mouth of the air passage '51. The spindle 63, attached to the air valve 62 extends through a gland plug 61 screwed into the outer end portion of the valve housing 54. Gland packing 68 is positioned between the gland plug 61 and an inwardlyY extending collar 16 in the valve housing 54 to form a seal around the spindle 63 against the leakage of air from the longitudinal passage 51 in the valve housing 54, and collar 69, mounted on the spindle 63, is urged against the packing 68 by a spring 69a, mounted between the gland plug 61 and the collar 69, to thereby press the packing 68 against the collar 16. A compression spring 12 having one end portion engaged with the outer face of the air valve 62 and the other end portion thereof engaged with the inner surface of the handle 24 within a recess 13 formed therein, tends to normally maintain the valve 62 in engagement with the valve seat 65 on the valve housing 54 and thereby seal the connection between the air chamber 5| and the longitudinal passage 51 in the valve housing 54.l As will be described in greater detail hereinafter the outer end portion of the spindle 63 engages a trigger 15 by which the spindle 63 and, therefore, the valve 62, may be moved inwardly to unseat Athe valve 62 from the valve seat 65 and thereby permitow of lair,

The paint so discharged from the.

4 from the air chamber 5| into the air passage 51 in the valve housing '54.

A second passageway 11, substantially parallel to the air passage 35, is formed in the handle 24 and extends substantially through the entire length thereof. The cuter end portion of the passageway 11 in the handle 24 is tapped to provide threads 18 into which e, suitable plug 19 may be screwed to seal this outer end portion of the passageway 11 against the escape of air therefrom. At the point where the passageway 11 intersects the air chamber 5|, the valve housing 54 is, somewhat reduced in cross section so that a space 8| is provided between the valve housing 54 and the side walls of the air chamber 5|V` and the air passage 11, so that air flowing through the openings 53m-d may flow through the enlarged opening 8| around the valve housing 54 up into that portion of the air passage 11 thereabove.

From the valve housing 54 the air passage 11 extends on into the handle 24 and intersects with another bore 83 formed transversely through the handle 24. A threaded sleeve housing 85 is screwed into the bore 83 and seats against a shoulder 86 formed therein. A smooth sleeve 88 is slidably mounted in the sleeve housing and has an opening 89 from which a needle valve 9| extends into the nozzle 30, the opening 89 being of substantially greater diameter than the needle valve 9i. A collar S3 having a plug 94 screwed into the free end is screwed onto the sleeve housing 85 and a compression spring 95V is mounted between the plugv94 and the head 91 of the needle valve 5| and tends to press the needle valve 6| outwardly from the sleeve 68.

At the point where the passageway 11 intersects the bore S3 in the handle 24, the sleeve housing 85 is reduced in cross section so that a space |66 is formed between the sleeve housing 85 and the side walls of the bore 83 and the air passage 11, so that air may pass through the space |60 from that portion of the passageway 11 on one side of the sleeve housing 85 to that portion of the passageway 11 on the other side of the sleeve housing 85.

From the sleeve housing 85 the passageway 11 extends4 on through the handle 24 and intersects with an air passage |62 which extends substantially longitudinally through the body 22 of the gun 20.

A master control valve |54 is mounted in a bushing |65 screwed into one end portion of the air passage |62 and acts to control the flow of air from the passage 11 into the passage |62 as will be described in greater detail presently.

An air passage |31 extends substantially longitudinally through one end portion of the master control valve |04, and another opening |08 eX- tends transversely through, and is so positioned in the side wall of the master control valve |04 that when the control valve |64 is in operable position in the air passage |62, the transverse passage |58 may be aligned with the passage 11 thereby permitting air to ilow from the passage 11 through the transverse passage HB8 and the longitudinal passage |61, into the air passage |02.

A collar |03, having splines lla, |105, ||0c and ||6d engaged with corresponding slots formed in the outer end portion of the control valve |64, is non-rotatably mounted on the outer end portion of the control valve |04 and is held thereon by a hollow retaining screw A thumb piece 3 projects transversely from the collar |09 and forms a convenient handle for rotating the control' valve |04 in the bushing to thereby movethe transverse opening |08V in the control Valve |04 into or out of alignmentv with the passageway 11. The master control valve |04 fits snugly into the passageway |02 and, therefore, it will be apparent' that whenthe control valve |04 is turned into positions, such.. as those shown in Figs. 1, 2, 3 and 4, wherein the transverse opening |08 therein is in either direct alignment or partial alignment with the passageway 11, air may flow from the passageway 11 through the transverse opening |08 in the control valve |04 into the longitudinal-opening |01 and on into the air passage |02.rv However, fromy the foregoing it will be apparent that when the valve |04 is rotated about its longitudinal axis to a position (not shown) V90 from .the 'posi-A tion shown in Figs. 1 and 2, the opening` |08 therein is moved entirely out of alignment with thepassage 11 so that the valve |04 effectively closes the connection between the passageway 11 and the passageway |02 and thereby preventsv air from flowing therebetween. To effectively seal the control valve |04 against the leakage of air therearound, the control Valve Y|04 not only seats tightly in the air passage |02 but also a suitable sealing member such as an O-ring ||5 is mounted between a shoulder l|2 formed on thelcontrol valve |04 and -a shoulder ||4 in the air passage |02.

The vhollow retaining screw screwed into the outer end portion of the master control valve |04, holds a collar |20, on the inner end portion of ahollow adjusting plug |22, in engagement with a shoulder |23 formed in the control member |04. As is best seen in Figs. 1, 4, '1 and 8, the collar |20 on the hollow adjusting plug |22 has a substantially oblong shaped opening extending therethrough, and which opening embraces a correspondingly oblong shaped end portion |25 of a needle valve |21. Thev needle valve |21 extends through the control valve |04 and the air passage |02 in the body 22, into an air passage |29 in the coupling member 32. VThe needle valve |21 has threads |3| formed on one end portion thereof which engage threads |32 formed rin the control VValve |04. l The adjusting plug |22 has a knurled knob |34 thereon vby which the adjusting plug |22 may be turned to thereby rotate the needle valve |21 and, through the engagement of the threads I3| on the needle valve |21 with the threads |32 in the master control Valve |04, either advance or retract the needle valve |21 toward or away from the passage |29 in the coupling member 32, to thereby vary the effective size of the mouth |30 of the air passage |29 for the purposes which will bediscussed in greater detail hereinafter. A bowed washer |35 ismounted on the adjusting plug |22 and frictionally engages the knurled knob |34 and the hollow retaining screw and thereby affords a frictional retaining member for holding the needle valve |21 in adjusted position.

The air which flows through the air lpassage |02 in the body 22 of the spray gun 20, when the control valve |04 is turned in such position that the transverse passage |08 therein is in alignment or partial alignment with the passageway 11, enters a passageway |36 in the coupling member 32, which passageway |36 is in alignment with the passageway |02. From the passageway |36 the air may flow through either one of two courses, or both. One of these courses is' from the passageway |36 around the free end yof the needle va1ve|21 into the passage |29. into: ai

circular 'passage 4|40 in the-coupling memberL32Q. Fig. 4, and from there through suitable passages such as slots |42a, and |42b,`-Fig. 4, formed in the rear end portionof the air discharge nozzle 28, into an 'annular passage |43'Jform'ed 'between the liquid-discharge nozzle 30 and the-air discharge nozzle 28, vas is more fully described in my aforesaid co-pendingapplication,'Serial No. 734,819. From the annular passagei|43 the air may flow through two passages" |45 and |46 formed in the wings 46and 41,3respectively,fin

the'Y air' discharge nozzle 28, and outwardly .from

nozzle 28, as discussed in greater detail-inthe' aforementioned co-pending application,l Serial PGUSSI LOVGQQZ JSQUIUN lualgcl MOU GISSL '0N on July 3, 1951. From the annular space |54 the? air may exit from the air discharge nozzle 28- through the central orifice 4| v and 1 through auxiliary orifices |56 and |51 for purposes which will be described in greater detail hereinafter. i

It will be noted that, as best seen in Fig. 1,'the

coupling member 32` of the nozzlehead 26 has an opening |59 formed therein vthrough whichv a screw |60 extends, the screw |60 being in threaded engagement with the body- 22 ofthe spray gun 20 in a tapped'opening |62 provided therein. A nipple |64, having threads |65 formed thereon, extends through an opening |61 formed in a flange |68 on the body 22 of the gun 20 and is held therein by a nut |69'. Therefore, it will be` seen that when the couplingmember 3.2is mounted on the body 22 of the spray gun720 it is securely held in position by the screw |60 4and thenutlSS. v Y

The air dischargenozzle 28 is securely held on the outer end portion of the coupling member 32 by the` collar 34 which hasan inwardlyextending flange |10 which engages an outwardly 16xtending collar |11 formed on the inner yendportion of the air discharge nozzle 28; and which also has threads |19-which are operably engaged with correspondingthreads on the outer 'end` portion ofl the coupling member-32v tothereby hold another flange |10a on the collar 34ytightly against a spring washer |82, Fig. l4, positionedbetween the outer end of thecouplingurnember 32and the flange |1011.. The pressure'exerted byV the spring washer |82 tends .to frictionally hold; the collar 34 in adjusted position ,onthewcouplingj the liquid discharge nozzle 30 -is screwedinto.

position in the leg |88 ofthe passage |89, acollar |90 on' the nozzle ,30 -is in engagementwiththe `ow from 4the.

frontend of the coupling member 32, and a suitable sealing member, such as an O-ring |92, may be positioned therebetween; and the peripheral edge 9| of the collar |90 is in engagement with a complementary surface on the inner edge portion of the air discharge nozzle 23. The other leg |93 of the L-shaped passage |89 has threads |95 tapped in the outer end portion thereof which, as is best shown in Fig. 1, are engageable with complementary threads |91 formed on the free end portion of the coupling pipe 39 so that, as will be'discussed in greater detail hereinafter, paint may flow from the container 31 through the pipe 39 into the leg |93 of the L-shaped passage |89 and out through the other leg |88 and the jet |84.

The trigger comprises a bifurcated lever having a nger grip |99, Fig. 1, and bifurcations and 202, Fig. 4. rIhe bifurcations 20| and 202 extend up past opposite sides of the body 22 of the gun 20 and are pivotally attached thereto by any suitable means such as a bolt 204, the finger grip |99 of the trigger 15 extending downwardly therefrom and lying in front of the spindle 63 on the valve 62.

The needle valve 9| extends forwardly from the sleeve 88 through the space between the bifurcations 20| and 202, forwardly through the nipple |64 on the coupling member 32 into the leg |88 of the elbow-shaped passage |89, the tapered end portion 91a of the needle valve 9| cooperating with the forward end portion of the liquid discharge nozzle 30, adjacent tothe jet |84, to Ycontrol the flow of coating material through the jet |84 in a manner which will be L discussed in greater detail hereinafter. 'I 'he space between the nipple |64 and the needle valve 9| is sealed by gland packing 208 positioned within the nipple |64. A collar 2 0 is slidably mounted on the needle valve 9| within the nipple |64 and is urged against the packing 208 by one end of a spring 2 I the other end of which presses against a gland nut 2 |2 screwed onto the threads |55 of the nipple |54, and which is operable to be advanced onto the nipple |94 to push the spring 2| l inwardly to thereby increase the pressure on the collar 2|0 and, therefore, the gland packing 208, whenever necessary.

During a typical operation of my novel spray gun, the spray gun 20 is attached to an air hose or the like by a suitable coupling member screwed into the threads 52 in the passage 35, and compressed air is fed to the gun from the air hose at.- tached to the passageway in the handle 24. When it is desired to operate the gun, the trigger 15 is manually pulled or squeezed toward the handle 24, to the left as viewed in Fig. 1, to thereby unseat the air valve |52 from the valve seat 65 and permit air to flow through the longitudinal opening 51 and the transverse openings 50a-d in the valve housing 54, into the air passage 11, through the space |00 and, the master control valve |04 being turned into position where the transverse opening |08 therein is in at least vpartial alignment with the air passage 11, the air flows from the space |00 on through the passage 11, through the transverse opening |08, into the longitudinal opening |01 in the control valve |04, and from there out through the passage |02 in the body 22 into the passage |36 in the coupling member 32. As previously described, part of the air then flows from the passage |36 through the passage through the passages I52a-b into the annular space |54 between the liquid nozzle 30' and the air nozzle 28 from whence it flows outwardly from the nozzle head 26 through the orifices 4|,

|56 and |51. Although my novel gurl. may be used in a system where paint, or other coating material, is fed to the gun under pressure, it is so constructed that it may` also be used in systems where the paint is not vf ed under positive pressure, and for this purpose the construction of the gun 20 is such that the aspirating eiiect produced by the outward flow of the air through the central orifice 4| is sufcient to cause paint to be drawn up from the container 31 through the pipe 39 and the passage |89, and to be discharged from the jet |84 into the stream of air flowing from the central orice 4 I, where it is intimately mixed with the air in a fine spray and blown from the gun 20. It will be understood by those skilled in the art that the atomizing effect of the stream of air flowing from the central orifice 4| on the coating material iiowing from the jet |34 will be realized in my novel gun, whether the coating material is fed under pressure or by aspiration, and that in both cases the air and coating material will be intimately mixed together in a fine spray.

Part of the air which enters the passage |35` fiows between the tapered end portion |21a'of the needle valve |21 and the mouth |30 of the passageway |29 into the passageway |29. From the passageway |29 air flows into the circular passageway |40, and from there through the slots |42a-b into the annular passageway |43 between the air discharge nozzle ,28 and the liquid discharge nozzle 30. From the annular passageway |43, the air fiows through the passageways |45 and |46, in the wings 46 and 41, respectively, and is discharged therefrom through the orifices 43 and 44, respectively, at the proper angle to properly modify the paint spray fiowing from the jet |84. The detailed construction and operation of a nozzle to effect proper modification of the paint spray iiowing from the jet |84 mixed with the air flowing from the central orifice 4| is fully discussed in the copending application of Burr W. Mantle, Serial Number 672,077, filed May 24, 1946, now Patent Number 2,511,356 issued on June 13, 1950.

I have found that during the operation of a spray gun there is a tendency for a certain portion of the paint which passes outwardly from the jet |84 to swirl away from the air stream passing from the central orifice 4| and be thrown onto the adjacent front surface of the nozzle head. In spray guns of the character with which my invention is primarly concerned, wherein orifices in the nozzle head, such as the orifices 43 and 44, are utilized to modify the paint spray issuing from the gun, the depositing of paint on adjacent front surfaces of the nozzle head is detrimental to the proper operation of the gun because it tends to accumulate and cake thereon and eventually to alter vthe effective size and characteristics of the orifices through which the modifying air flows. To prevent this, I have provided the orifices |50 and |51 which are positioned in the front face of the air discharge nozzle 28 in such a manner that the air which flows therefrom is directed against the front face of the wings 46 and 41 just inside the orifices 43 and 44 so that the air stream issuing from the orifices |56 and |51 tends to sweep off anyv paint which might be deposited on the wings 45 and 41 and which, if not removed, would alter the effective size and the discharge characteristics of the orifices 43 and 44. Thus it will be seen that in my novel gun 2.0, the orifices |56 and |51 provide an effective way of keeping the orifices '43 'and' 44free of accumulated paint and therebyv assist in preventing undesirable alteration of the operating characteristics of the gun by the accumulation of paint on the wings 46 and 41 during the voperation thereof. u

Control of the paint iiow through the jet |84 is effected in part through control of the velocity of the air issuing from the oriiice 4|, and in part through operation of the needle valve 9| by the trigger 15. For this latter control, shoulders 2|8. Figs. 1 and 4, are formed on the bifurcations 20| and 202 of the trigger 15 and are engageable with the free end portion of the sleeve 88. Thus it will be seen that, the trigger 15 being at all times in engagement with the spindle v63 on the -air valve 62, upon depression of the trig.- ger 15 toward the handle 24, the air valve 62 is first opened so that air is permitted to flow from the passage 35 through the gun 20 and out through the central oriice 4| in the air nozzle 28, as previously described, and that upon further depression of the trigger 15 the shoulder 2|8 thereon engages the free end portion of the sleeve 88 and pushes the sleeve 88 outwardly, or to the left as viewed in Fig. 1. Outward movement of the sleeve 88 causes the free end portion of the sleeve 88 to press against the head 91 of the needle valve 9| and thereby withdraw the needle valve 9| from the jet |84. It will be apparent that one of the controlling factors in determining the amount of paint which will flow through the jet |84 is the size ofthe opening through this jet, and that the position of the needle valve 9| with respect thereto is a controlling factor in determining this. Therefore, from the foregoing it will be apparent that, as the trigger 15 is depressed toward the handleV 24, the needle valve 9| is withdrawn from the opening in the jet |84 so that the eiective opening of the jet |84 is enlarged to permit a larger quantity of paint to flow therethrough, and, conversely, as the trigger 15 is released by the operator, the Aspring 90 is effective to move the needle valve 9| back toward the jet |84 to thereby restrict the effective opening of the'jet |84 and thereby retard the flow of paint therethrough. This, it will be seen, gives the operator of my spray gun 20 a quick and easily operated control of the flow of paint from the gun.y

The master control valve |04, as will be apparent to those skilled in the art, may be readily adjusted by turning'the thumb piece l I3 to any position between the position in which the passageway |08 is completely out of alignment with the passageway 11-and, therefore, no air is permitted to flow from the passageway 11 through the control valve |04, and the position,.shown in Figs. 1` and 2, wherein the transverse passage |08 is in complete alignment with the passage'- way 11 and the control valve |04 is completely open to permit a maximum air flow therethrough into the passageway |02. Thus it will be seen that the master control valve 04 may be adjusted to permit any desired amount of air to flow therethrough, and thereby provides an effective means for regulating the pressure of the compressed air reaching the needle valve |21.- Also, it'will vbe seen .that the. levery ||3 by which `the master control :valve |04 is adjusted, is in a readilyaccessible position so that .the controlvalve |04 may be easily adjusted by the operator without interrupting operationof the spray gun 20,l but does not project an undesirable amount from-the body. 22 of the spray gun'and :blendsfinto the outlinesA of .the 4body 2 2' so as tobetherebyprotectedfrom'ibeing knocked out of adjusted posi- -tion. l

While the master control valve |04provides ad'ditiona1 valve mechanism kfor this purpose whereby the fine' adjustment of the air ilow through the nozzle head 26 may be accomplished. Thus it will be apparent to those skilled in the art that byl rotating the knurled knob |34 in the proper direction, the needle valve |21 may be screwed into or out ofthe master control valve |04to thereby adjust the position of the needle valve |21 relative to :the mouth |30v of lthe passage I29 inthe coupling member 32 and thereby regulate the modifying air stream which' flows outwardly from the' wings 48 and 41 of the air discharge nozzle 28 through the orifices 43 and 44.' It will be noted that while the knurled knob v|34 on the adjusting plug |22 is in a readily accessible vpositionr and" may be Yreadily turned by the operator duringroperation of my gun 20 to change the setting ofthe needle valve |21, it does not project an undesirable amount, and, like the lever V| I'3, blends in well with the outlines of the body 22'so asto be protected from being accidentally knocked outofj position during operation of the gun 20. Moreover, it will be noted that in adjustingV the needle valve |21, the knurled knob |34 and the adjusting plug |22 are merely rotated ontheir longitudinal axis-and do not move longitudinally of the body 22 of the gun 20, so that this same desirable position of -the knurled knob |34 longitudinally of the barrel 22 is maintained for all Vpositions of adjustment of the needle valve-|21. This represents a substantial improvement `over the sprayguns heretofore known tothepri'cnr art.

' As was previously mentioned, the opening 89 `in the sleeve 88 through which the needle fvalve Y9| extends is preferably of relatively considerably greater diameter than the diameter of the needle valve 9|. This being true .it will be apparent that the needle valve9l may be swiveled in any direction', and to any extent, within the confines ofthe walls of'th-e opening 89, as is discussed in theaforemention-ed patent, Serial No. 734,819, nowPatent NumberV 2,559,407, issued on July-3,

Hereto-forein'the art,'coring` and machining'of openings such as the openings 83 andr |61 has presented a serious problem because, although these openings werein two separated members they had to be relatively accur-ately'aligned so that the needle'valves heretofore known could be properly inserted therein. However, in my spray gun 20, because ofthe novel manner in which I mount my needle valve 9|, the needle valve may be swiveled suiciently that the openings 83 and |61 need be aligned onlywithin relatively broad limits, which are readily obtained in production, in order to properly position the needle valve 9| therein and need not be aligned with the relatively narrow limits which were heretofore necessary anddicult-to obtain. y y l `Relatively fine adjustment of the position of the needle valve 9| relative to the jet |84 may be effected by lscrewing the collar 93 onto and olf from the sleeve housing to thereby vary the compression of the spring 96. It will be apparent that this adjustment is also eiective toV control the extent to which the needle valve 9| can be withdrawn yfrom the jet |84 by operation of the trigger 15, the movement of the collar 93 onto or off ,from Ithe housing 85 correspondingly moving 1 l theplug 94'to therebyvary the position atwhich the plug 94 will strike the outer end of the sleeve. 88.

From the foregoing it willbe apparent to those skilledzin the art that the opening 89 in the sleeve 88 may be considerably larger than the diameter of theneedle valve 9| and the needle valve 9| can float therein, so as to automatically adjust itself'for misalignment which may occur in the body of the needle valve 9|. Also it will be apparent that to change the needle valve 9|, all that is necessary is to unscrew the collar 93 from the sleeve housing 815 and pull out the sleeve 88 together with the needle valve 9|, the plug 94 then being removed from the collar 93, the compression spring 96 then being removed from the sleeve 88 and the sleeve 88 inverted, and the needle valve 9| permitted to drop therefrom. A new needle valve 9| may then be inserted into position in the sleeve 88 and the needle valve 9| and the sleeve 88` pushed,` into position in the sleeve housing 85, the compression spring 96 reinserted into the sleeve 88, the plug 9 4 screwed back into the collar 93, and the collar 93 screwed back onto the sleeve housing 85. Thus it willbe seen that removaland replacement of the needle valve 9| is a relatively simple operationin my novel spray gun 20.

From the foregoing description of the construction and operation of my novel spray gun, it will' be apparent to those -skilled in the art that I have provided a lightweight, practical spray gun which is both positive `and emcient in operation and which can. be economically manufactured commercially, a'll of the internal openings. therein being formed by the lsimplest types of coring and drilling operations or the like.

Furthermore, it will -be noted thatvmy spray g-un is eiiciently sealed again-st undesirable air leaks and that the various valves there-of are held positioned so as to be readily accessible to the o-perator but also so as to be protected from being accidentally knock-ed |out of adjustment.

Thus. while I have illustrated and described a preferred embodiment of my invention, it is to be understood that this is capable of variation andmodication and I therefore do not wish to be limit-ed to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims:

I claim:

l. A spray gun comprising the combination of a. handle having. anair passage therethrough, va body extending from one end of 'said handle andhaving an air passage therethrough in communication with the air passage in said handle, a nozzle head attached to one end portion of'said body and adapted to discharge air from the air passage in said body, means for controlling the flow of air through said nozzle head, said means including avalve member rotatably mounted in the-passageway in said kbody and a needle valve in the last mentioned passageway and in threaded engagement with said valve member, said `valve member being operable upon rotation thereof to open and closetheV passageway in said body, a valve VseatY mounted on said body member in alignment with said' needle valve, said needle valve being movable into and out of operative engagement with said valve seat upon longitudinal movement of said needle valve within the passageway in said body to vary the flow of air through said nozzle head, an adjusting member rotatably mounted'in said valve member'in substantially xedvendwise position and in' operable engagement With said needle valve, said-adjusting vmember being operable upon rotation thereof relative to said'valve `member to rotate said needle valve and thereby move said needle valve longitu'dinally in the passageway in said body, and means projecting from said valve member exteriorly of said body for rotating said valve member to thereby open and close the air passage in said body.

2. A spray gun comprising a handle having a passage for air therethrough, a body member projecting from one end of said handle and having a passage for air therethrough in communication with the passage in said handle, a nozzle head connected to said body member and adapted to discharge air from the passage in said body member, means for controlling the discharge of air through said nozzle head including a valve seat mounted on said body member in communication With said last mentioned passageway, and a needle valve rotatably mounted in said passage in said body and movable toward and away from said valve seat upon longitudinal movement to vary the rate of discharge of air through said nozzle head, means threadedly engaged with said needle valve for moving said needle valve longitudinally in the passage in said body upon rotation of said'needle valve relative to said last mentioned means, and a sleeve member rotatably mounted in said body in substantially xed endwise position therein, said sleeve member being operatively engaged with said needle valve and being operableupon rotation relative to said body to rotate said needle valve and thereby move said needle valve longitudinally in the passage in said body to thereby vary: the discharge of air through said nozzle head.

3. In a` spray gunV of the type adapted to permit the passage of air therethrough, a handle having an air passageway therethrough, a body attached tosaid handle and having an air passageway therethrough in interconnecting position relative to said passageway in said handle for the reception of air therefrom, a nozzle head connected to said body and having an air passageway in interconnecting position relative to said air passageway in said body member for the reception of air therefrom and extending outwardly from said nozzle head, and means for controlling the ilow of air through said passageways in said handle, said body and said nozzle head, said means comprising a valve member rotatably mounted for axial movement, upon rotation, in said passageway in said body adjacent to said passageway inY said handle and operable when disposed in a predetermined axial position of and in said passageway in said body to close said last mentioned passageway and said passageway in said handle and to thereby close communication between said passageways in said body and said handle, said valve member being operable when disposed in another predetermined axial position of and in said passageway in said body member to open communication between saidV last mentioned passageway and said passageway in said body member, a valve seat, and a needle valve operatively associated with said valve seat, said second valve being rotatably mounted in said iirst mentioned valve within said passageway in said body and extending axially of said body passageway toward said nozzle head for controlling the flow of air through said nozzle head, said second valvebeing movable axially in said body passageway toward and away from said valve seat and said nozzle head upon rotation relative to said rst mentioned valve, said needle valve being movable with said rst mentioned valve member during movement of said first mentioned valve member between said predetermined positions.

4. A spray gun comprising a handle having a passage for air therethrough, a body member projecting from one end of said handle and having a passage for air therethrough in communication with the passage in said handle, a nozzle head connected to said body member and adapted to discharge air from the passage in said body member, means for controlling the discharge of air through said nozzle head including a valve seat mounted on said body member, and a needle Valve rotatably mounted in said passage in said body and movable into and out of said Valve seat upon longitudinal movement to vary the rate of discharge of air through said nozzle head, another valve member rotatably mounted in said passage in said body and operable to control the eiective opening therethrough, said other valve member being in supporting eng-agement with said needle valve and being operable upon rotation of said needle valve relative thereto to move said needle valve longitudinally of said passage in said body,

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

UNITED STATES PATENTS Number Name Date 664,364 Von Wie Deo. 18, 1900 1,482,798 Kenney Feb. 5, 1924 1,586,010 Shelburne May 25, 1926 1,762,282 Stephan June 10, 1930 1,950,779 Bramsen Mar. 13, 1934 1,982,056 Jenkins Nov. 27, 1934 2,060,894 Potter Nov. 17, 1936 2,238,521 Gustafson Apr. 15, 1941

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