US2060894A

US2060894A - Spray gun

Info

Publication number: US2060894A
Application number: US723737A
Authority: US
Inventors: Russell L Potter
Original assignee: VILBIAS Co DE
Current assignee: DE VILBIAS Co; VILBIAS Co DE
Priority date: 1934-05-03
Filing date: 1934-05-03
Publication date: 1936-11-17
Anticipated expiration: 1953-11-17

Description

R.i L. POTTER Nov. 17, 1936.

SPRAY GUN Filed May 5, 1954 Patented Nov. 17, 1936 PATENT osFFlcE 2,050,894 SPR-AY GUN Russelli L. Potter, Toledo, Ohio, asslgnor to The Del Vilbiss Company, Toledo, milo, a corporation of Ohio 4Application May 3, 1934, Serial No. 723,737

12 Claims. (Cl. 299-11401) This invention relates to spray-guns of the type employed for discharging surface coating materials in spray-form, and pertains more par-v ticularly, but not exclusively, to guns of this character adapted to discharge a fan-shaped spray streaml A An important object of the invention resides in the manner employed for directing and controlling the supply of air under pressure to the main and supplemental air discharge orices of the gun head, and particularly the supply to said supplemental orifices, whereby the pressure of the air discharging from such orifices is uniform irrespective of the head adjustment or conditions of USS.

Further objects and advantages of the inven ltion of a spray-gun embodying the invention,

with parts in full; Fig. 2 is a'n enlarged section on the line 2 2 in Fig. l; Fig. 3 is an enlarged perspective view of the baille means employed for uniformly distributing the air supply to the supplemental discharge orifices; Fig. 4 is an enlarged longitudinal section, with parts in full, of the valve means employed for controlling the supply of air to the spray-head, and Figs. 5 and 6 -are different details of such means. l

Referring to the drawing, A designates the body or stock having at its rear end the lateral projecting handle B, and at its forward endthe enlargement C to which the spray-head D is atvtached.

Extending rearwardly through the body A from the upper portion of the enlargement C is a bore I for the passage of air, as hereinafter described,

vand below the forward end of such bore centrally orifice 6 in concentric relation to the material dispointof connection with the body enlargement C.

Aand the" nozzle 4 is engaged at' its outer rear edge by a union nut 8, which threads on a tubular excharge passage I 0, which orifices direct jets of air tension 9 of the enlargement C concentric to the inner nozzle. The outer nozzle 4 is provided at each of diametrically opposite sides of its main discharge orifice 6 with a supplemental air disin opposed relation against the combined air and lmaterial stream discharging from the inner nozzle 3 and orifice 5, as well understood in the art. The inner ends of the passages IU communicate with an annular passage I l provided in the nozzle i at lo the outer side of the point of connection of such nozzle with the ange l, so that there is no communication between the passage I I and the inner annular air passage 5, which latter communicates with the orifice t. l5

As is customary with spray-heads of this charl1 acter, the outer nozzle ii is adapted to have rotatable adjustment with respect to the inner'nozzle, so as to flatten the spray stream in any plane desired to suit the work to be performed.

The tubular extension 9 on the enlargement Cis spaced radially from the inner nozzle il and the portion of the enlargement C into which it threads to form an annular space therebetween, which space is divided into inner and outer annular chambers I2 and i3 by a tubular member lil, which has its rear end thrust against a coacting portion of the enlargement C and its forward end thrust against the flange l of the inner nozzle. The member lil is centered with respect to the inner nozzle by seating at its forward end over an annular shoulder on the flange l, as shown. The inner chamber I2 has communication with the passage 5 through a plurality of openings I5 provided in the flange l, and the outer chamber I3 has communication at its forward end with the annular passage I I from which the supplemental discharge passages I0 receive their air supply.

The outer'chamber I3 receives its air supply at its rear end through a passage I6, which registers with the forward end of the body bore I and communicates therethrough with a source of air pressure supply, as hereinafter described.

In order to provide an even distribution of air under pressure to both supplemental discharge passages I0 under all conditions, the member I4 is provided at its outer side, within the chamber I3, with a plurality of successively disposedvbailles, in the present instance, in the form of annular flanges I1, I8 and I@ (see Fig. 3), each having differentially arranged orifices therethrough, and which at their outer edges engage the tubular exltension 9, so as to divide the chamber I3 into a tion of the bore I at its forward end to provide a In order to eect a thorough equalizing of the air pressure entirely around the forward end of the chamber I3 before entering the annular passage IIF, the rear baille flange I'I is provided with one or more orificesI'Ia at opposite sides of the head axis and substantially a quarter way around in each direction from the air supplypassage I6.- The next flange I8 is provided equidi'stantly therearound with four notches I8, two of which are above and two below the orifices I'I'. The

last flange I9 is provided with a plurality of equidistantly spaced orifices |911 of greater number the forward endpf the bore I through an annular` passage 2U and segmental passage 2| v`provided in the enlargementC 'concentrically of the bore 2, the passage 20 extending through the bottom por'- port connection 22 therebetween.

A passage 25 is provided in the handle B forv connectionin any suitable manner, with a source of air pressure supply, and its passage. has communication with a port 26 opening` laterally into the rear end portion of the borev I.. A main normally closed shut-off valveZI is provided in the passage 25, being opened by an operation of the trigger 28, as well understood in the art.

The bore I opens without the rear end of the gun body A and receivesthrough such end a tube 30, which is threaded at its forward end in a slightly restricted portion of the bore I in advance of the port 22 with the forward end of its passage in communication with the orifice I 6.

. through which air is supplied to the chamber I3,

which latter maybe considered as a pressure equalizing chamber. .The rear end of the tube 3Il is provided with an enlargement 3| that iits snugly in the rear end of the bore I, and without the rear end .of the bore the. tube is provided with a further enlargement 32 that is adapted toshoul der against the marginal end wall of the bore and preferably has a portion of its periphery of hexagonal or other suitable form for engagement bya wrench to facilitate n turningnf the tube into or' out of threadedengagement at its forward end with the body enlargement C.

While the enlargement C has been referred to, in effect, as beinga lpart of the body A, it, in

. reality, constitutes a head construction which is separable from the body A and is secured thereto-by thetube 30,.which acts as a. bolt or rod for rigidly connecting the two parts of the gun body. Thisis a feature, which, in itself, `forms no par of thepresent invention. I

In order to prevent the tube .out of the bore I and thus becoming separated from the gun body when the head construction C,

D, is removed from the gun, the threaded end Vof the tube is slightly enlarged relative to theiadjacent portion thereof and the bore is provided in the body A adjacent to its point o'f connection with the head C with a reduced threaded'portion 33, thus requiring the vtube to be unthreaded through such portion when being 'removed from the body. lihe tube 3l) intermediate the inlet port yrelative to` the tube. l 1

:n.frin failing.

26 and outlet port 22 is smaller than the bore I, so as to permit air to pass through the bore around the tube from one of said ports to the other. It is thus apparent that the only control for the air passing to the main air discharge oriiice '6 of the spray-head is the main valve 21.

The tube 30 near. its rear end portion has cornmunication with the air space around the tube 'through ports 34, so that the supply of air. for the supplemental discharge orifices III of the spray-head is furnished through the tube.

air for this purpose is controlled by a valve 35,

which, in the presentinstanoe, is of tapered form and adapted to seat in a restricted portion of the tube passage provided slightly in advance of the ports 34 in the tube. The valve-stem is provided at its rear end portion withan enlargement 36 (Fig. 4), which in turn is providedv intermediate its ends with a.. further enlargement31 that isthreaded into the rear end of the tube 30, so that a turning of the valve-stem' relative to the y tube will effect an advance or retracting of the valve relative to its seat. The outer end of the steml 36 projects from the rear end of the tube through asuitable packing gland 38 and is provided at its outer end Awith a knurl'ed head 39 to facilitate turning.

It is desirable to provide some means for effecting a drag. against a freeV turning of the valve-stem 36 so that the valve may not'be accidentally movedfrom an adjusted setting found desirable for the particular spraying operation in hand. While it is not newvto provide a drag onl a valve of this character, the means heretofore Yemployed for accomplishing this have, so far as I am aware, been unsatisfactory and impractical for many classes of work. /An efcient means for accomplishing such a drag consists in mounting a skirt member 40 on the'valve-stem 36 in ivance of the threaded portion 31 and having its .,Qrward end slotted to provide spring fingers 4I which normally exert an outward pressure against the wall of the tube 30 and thus exert a considerable drag against a turning of the valve Another detailed construction of the valve mechanism .that is of importance in connection lwith a tool of this character is the provision of an adjustable dial member in connection-with the control headv 39 o'f thel valve. This member comprises "a --normal slightly cupped disk .45,

which is held Afor rotatablel adjustment within the outer recessed end of the valve-head by a screw 46. The edge of the disk is in contact with l the bottom of the head recess and it is substanltially flattened against the head by a tightening of the screw. The' disk is ofv spring metal, so

'that when nattened, or. partially' flattened by the 4engagement ofr the screw, a `suillcient binding action is provided between the valve-head and screw to prevent a. free turning of the The disk is provided with graduations which.v are' adapted to register with some stationary point' on the gun body to indicate the extent of turn-v ing adjustment. of thevalve-head relative to the body. It is found inl pracctice that, due` to variations in'the machining of the various parts involved, it would be quite'diicult and expensive to make -the'threading engagement ofthe tube. 38 with the spray-head body, and the valve-stem with said tube, and other relative dimensions rof -the various parts,-so exact that a vfixed dial on the valve and a marker-line on the body would bear the same relation in anumber of guns for .the same amount .of valve openinl'g.l Itgis also accesos found that there is considerable objection to removingvalves after determining how they set in the valve body and then marking them. Replacement valves would also be a problem if such procedure were followed. These objections are obviated and the proper adjustment of the valves made simple and more or less permanent by theuse lof a dial disk d frictionally held to the valvehead. `With this design of movable dial, should wear ofthe valve or the valve-seat alter the standard original setting between the dial and the body mark, the dial may be easily and quickly reset to correspond to the original setting. To facilitateadjustment of the dial, a hole dfi is provided therein into which a pointed tool may be inserted.

.Tit will be) appreciated from the foregoing that in the use of my improved spray-gun, the operating air is supplied to the main and supple- 'mental discharge orifices of the spray-head through distinct passages provided through a common bore in the gun body; that the air to the supplemental discharge orifices is controlled in a simple andconyenient manner separate from the control means for the main air supply; jthat such control is located near the rear end of the gun body where it is convenient of access, and

that the air for the supplemental discharge orifices passes through a. pressure equalizing chamber in the spray-head before reaching such orifices, so that the pressure is uniform in its discharge from both oriflces irrespective of the position oi such orifices. This latter is an `iinportant feature, as it obviates the objection frequently encountered in the use of spray-guns,

that the pressure of air discharging from the two supplemental orifices varies, thus effecting the stream flattening emciency of such air.

It is further apparent that with the present invention the tube 30 not only constitutes a means for' detachably uniting thev body A and sprayhead portion C, D, of the gun, but also forms a v passage for the airto a predetermined portion of the spray-head and constitutes with the control valve an assembly which is removable as a unit. from. the gun. It will be understood in practice that the valve 35 is set to suit the 'desired volume and pressure discharge of' air from the supplemental orifices to` suit the particular communication therewith, a member extended` throughsaid bore in shouldered engagement with a part thereof and having releasable engagement with the spray-head to unite the body and spray-head in assembled relation, said main and supplemental orifice distributing chambers having respective communication, onevthrough said bore and the otherthrough said. member, with'- said supply passage,and means associated withone of said passages for controlling the supply of air passing therethrough to the'supplemental orice's '2. In a spray-gun, a body having a-longitudinally extending bore therein, a spray-head detachably carried by the body and having main tion,

'adapted to have communication with a source ,lar member extending through said bore' in engagement with a part thereof and having engagement at its forward end with the spray-head to retain the body and head in assembled relasaid main and supplemental passages of .air pressure supply, one through said bore and the other through said member, and valve means cooperating with one of said passages to control the supply of air to the supplemental orifices.

3. In a spray-gun. a body having a longitudinal bore therethrough and a passage adapted Ito open communication between said bore and a source of air pressure supply, a spray-head detachably carried by said body and having main and supplemental air discharge orifices, a tubular member extended through said bore in coaction with a portion of the body and having threaded engagement at its forward end with 'the spray-head to retain the body and sprayhead in assembled relation, said main and supplemental discharge orifices having respective communication through`said bore and tubular member with said supply passage, and a valve mounted in said tubular member and operable from without the rear` end of said member and bore to control the supply of air to said supplemental orinces.

e. lin a spray-gun, a body having a longitudinal bore therethroughy and a passage adapted to open communication between said bore and a source of air pressure supply, a spray-head detachably carried by said body and having main and supplemental air discharge orifices, a tubular member extended through said bore in shouldered coaction with a portion of the body and having threaded engagement at its forward end with the spray-head to retain the body and-` .spray-head in assembled relation, said main and supplemental discharge orifices having respective communication through said bore and tubular member with said supply passage, and valve charge orifices, said main orifice having com-' munication with the forward end of said longitudinal passage to receive its air supply therefrom, a tubular member mounted in said longitudinal passage and"having detachable-engagement with lthe spray-head to retain the sprayhead and body in assembled relation, said meml itself having communication at its forward end .with the supplemental discharge orifices and at its rear end portion with a portion of the gun body through which air under pressure is supplied to said longitudinal passage.

6.' In a spray-gun, a gun body, a spray-head, a tubular member projected through the body and operable to unite the body and head in assembled relation and vforming an air supply passage to a portion of the spray-head, a valve mounted in said member to control the passage of air therethrough and having a stem part projecting without the rear end of the tube and threaded in the tube, whereby a turning of the stem. eects an adjustment of the valve, and

said member ,to resist a turning-of the stem.

7. In a spray-gun, agun body, a spray-head carried thereby" and having maink and supplemental air discharge orifices and4 separatefair chambers therefor, said body having a bore extending rearwardly from the 'spray-head with its forward end in communication with one, oi

said chambers and its rear end in communication" with a source of air pressure supply, a tube vi-gterial'supply throat in its forward en d, a material dischargenozzle projecting from said throat and having an annular `flange in advance of the body fpart,` "said` lpart having van annularabutment v\'flangerearwardly of said `no'zirlel iiange and a `forv'vard extension without saidjabutnijent flange mounted in said bore-and forming a separate passage from the .bore in communication at its' forward end with the other of said chambers;v and at its rear end with the source of air pres-` sure supply, and means associated Vwith said tube.- to lregulate the volume of air passing theref'vr y anduoutwardlyspaced withrespectet' a tubular 'member in abutment at fitsA lends with said flanges and dividing. the space .betweensfaid having main and supplemental air discharge orifices and a separate air chamber for each, said y 8'. In aspray-gun, a gun body, a spray-head (carried by the body at its forward end, said head body having a bore extending rearwardlytherein from adjacent the spray-head and forming an air passage. with its forward end in communisages having communication rearwardly of the head with an air pressure supply source.

9. In a spray-gun, a gun body, a spray-head carried by the body at its forward end, said head having main and supplemental air discharge orices and a separate air chamber for each, said body having a bore extending rearwardly therein from adjacent the spray-head and forming an air`. passage with its forward end in communicationwith one of said chambers, a tube extending rearwardly in .said bore from adjacent the sprayhead and forming 'a second air passage with its forward end in communication with the other and aiseparate means for regulating the passage l of air through one of said passages.

10. In a spray-gun, a gun body having a sprayhead at one end and a handle at the other end,

said head having main andsupplementalair discharge orifices and separate air supply chambers therefor, said body having a bore v'extending rearwardly from adjacent the head and forming an air passage with its forward end incommunication with oneof said chambers, a tube on, said bore` forminga secundair passage with it'sffforward 'end in communication with the otherfof said chambers. said passages adapted'for common f communication at theirgrear end"portions with .an'air pressure supply source through said handle, a main control valve carried by thev handle for .thesupplyof air to saidpassages, anda second `control. valve mounted in the rear end of said -,bore `and controlling the passage through said -..tube. 1g= l lll In a spray-gun, 'a bodypart having a ma- "aid nozzle,

end of said inner nozzle and havingrearward abutment against said first annular flange and g providing a main discharge orifice, said outer nozzle also having ,supplemental air discharge passages, and means releasably joining the outer nozzle to the body. part, said main Vair discharge.

orifice having communication through saidinner air` chamber and said supplemental passages having baffled communication through said outer chamber with a source of air pressure supply.

'12, AIn a spray-gun, a body part having a material supply throat in its forward end, an annular extension without said throat and concentric thereto and an annular abutment internally and rearwardly of said extension, an inner material discharge nozzle projecting from said throat and having an annular flange in advance of said abutment; a tubular member in opposite end abutment with said -'ange and abutment and dividing thespace between-said nozzle andextension into inner and outer air chambers, a plurality of anges on said member dividing said outer'chamber into a plurality of annular passages having staggered communication with each otherthrough the flanges, an outer air discharge nozzle in rearward abutmentagainst said first flange and having a main' vair dischargejorifice associated with lthe inner nozzle discharge and having supplemental air discharge orifices, said J- v main orice having communication .through said inner air chamber and said supplemental oriceshaving batlied communication through .said outer air chamber with a sourceV of air pressure supply. i

- RUSSELL L. POTTER.