US2760823A - Spray guns - Google Patents

Description

1956 F. J. KAVANAUGH 2,760,823

SPRAY cums Filed Feb. 8, 1954 ATTORNEYS 2,760,823 I Patentd Augsf-zs, 1

2,160.823' SPRAY GUNS Floyd J. Kavanaugh, 'GalvestomTeX assignor offifty percent to Clarke & Courts Investment Company, Houston, Tex.

Application February 8, 1954, Serial No. 408,797

'11 Claims? (Cl; 299-+88) This inventionrelates to spray guns and more particularly to such guns of thecompressedr airuatomization type constructed and arranged SOf'IhB/E changesof spray gun material may be made instantly without the need for cleaning any. part. of .the'gun or spray materialcontainer.

It is a general objectof Jthe presentinvention to provide a novel and improved spray gun. fitted with-interchangeable spray material containers- More particularly it is anobjectof this .invention t provide a spray gun-having. a handle air-controland airjet parts incorporated into one unit and-having one-ori.

more spray-liquid containers each incorporating a liquid.

nozzle together with means interfittingwith the first unit to automatically effect operatingrelationship of the-.--nozzle and jet for proper sprayinge:

An. important objectof-the present invention resides in the provision ofa spray gun in 'which no parts whatever require-c'leaning when changingfrom one material to another. or from one color paint to another.

Another important. object of this invention-resides 1n which a separate container is provided for each different the provision of a spray gun for paintsor the like-incolor or density of paint orthe like-and each is provided with an upwardly directed nozzle extending abovewt-he.

container cover for cooperation with the. gun proper which handles air only whereby no parts needcleanlng on changing colors or materials. a

An importantfeatureof theinvention consists inthe arrangement for. interchangeably attaching. the several;- containers to the gununitwhereby proper. relationship of liquid nozzle and air jetis insured.

A further feature of the inventionconsists ,in..the

provision of means to adjust the liquid nozzle. toward or away from the air jet.

Astill further feature of the invention resides-in the provision of quick adjustment means for raisingor lowen. ing the axis of the air jet in respect to the tipof the liquid nozzle. 7 I

Other and further objects and features of the lnvcntion will be more apparent to those skilledin the artupon a consideration -of the accompanyingdrawing and following specification wherein is disclosed a single exemplary embodiment of the invention with the understandingthat such modifications may he made there'inas fall lwlthln' the scope of the appended claims without departing .from the spirit of the invent-ion.

In said drawings:.

Fig. 1 is a side elevation of a spray gun constructed inaccordance with thepresent invention, the .attached.

liquid container being broken awayv below the cover thereof;

Fig. 2 is a central vertical section through the .apparatus shown in Fig. .1 and illustrating the air and'liquid flow passages, the adjustments and the like; and

Fig.: 3 is a front-elevation of the forward portion of the spray gun runit further illustrating the adjustment features.

Spray guns making use of compressed air t'a,loi"mt'1.r1'!

. 2 .};v forms-:and-xare used "for a widevariety iof purposes, including thea-T application: of? paints; ivarnishes and similar coatingssthez disseminationof inse'cticides; fungicides and similarlm'ater'ials; and; in many ofz the arts'and industries for the application of-'variousrliquids rand :suspensions.

Themoreorlessrstandardized'foms oft compressed air spray guns divide intoztwo general-classes; first the truly industrial t'ypeirin which both ithe iairiand the'liquid are suppliedthroughwhoses ewhich type;-finds its principal advantage;;where continuous use with the-rsame color of coating or 'the same liquid=takespl2icefi for a number of hours. ikWi-th -thi-s-ttypeaof lgun bothwthe liquid and air pass through spassagess in Fthekprincipaleparts thereof and at least. the fluid -passages imu st" beiclean'edcarefully 5 before changing to another materiel-1;? color; co'nsistency or" the like ot-sprayed. fluidw t'lhe secondform also passes the-air? throughj'apassagesin the principal :parts of the gun and picks ,uptheliquid from' a container-attached. to and carried by thegun. --Mosti-offl these have a11 eduction tube passingthroughg-at leastia portion of the gunmechanisrrnto bringithefliqnidinto proximity --to the air jet for proper atomization. If .wt-hediquid' is to be changed the container must be thoroughly eleanedwith a solvent-and a quantity of. this solvent mustebetsprayed through the gunrto-clean-out=the .passages leading. to andithrough the fluid nozzle; i

Form-any-uses such-guns=are--.admirable. but where the type offiuidmust be changed-=often, -where it is highly volatile, or quick changesinycousistency-or color are necessary for blending. tor thezvlikerthe: requirement for cleaning of.the.=several -parts before-each changeis not onlylaborious :but -time; consuming andiwasteful of mateflair"! It is .thereforegthe purpose=.of ..-the' present invention to provide a sprayigun whi chumay. befidivided into two general parts, the fi rst being. ithe- :principal body unit includ-ingithe handle -the .air passage a trigger actuated air control valve;and:the airz jet while the-second unit,

which is :usually supp lied in multiple, includes a spray 7 liquid. container, S-a liquid nozzletconnected thereto and means: for-attaching th-is sunitito thei-principal unit of the. gun. Thus .by. having a plurality of containers, each with "a diiferentwliquid,changesr can be made instantlysince no liquid passages need cleaning, each nozzle and its connecting passages.remainingwvith its container. al-' I lotted to a specific liquidm sMechanism-zis:provided toins'ure proper relationship of the agtesof .jet and nozzle, and adjusting means are available for actuation without stopping theigspray operation 'I his-Ltype. of 'gun is extremelyusefultto painters .doingftouching up or repair workonvehicles, oflide furniture, machines and the like, and in fact any place where frequentchanges of sprayed fiuidior color are necessary. v

Referring-I now to thedraivingdt willbc seen that the principal unit of the" gun takes a more or less conventional form, having the"usual handle i ltl sha'ped somewhat like thator an" automatic pistoL- Conveniently the main air pa's'sa-ge..1 1,extends longitudinally through the handle and I terminates at sthelower'end in'lthe nipple 12 to WhlCh=-.-"

an air' hose maybe attached. A-tthe upper end of the passage fit is intersected by 'tl re valv e body '13- extending through the u perparmf the ha'ndle'jhnd having the movable valve disc '14,- its actuating plunger 15 and closing springzle allof" r'ho're 'or less conventional -form.

and operatiifg'inan' oby'oii's; manner. A bore 11mnects' the space heliindjthe'valve disc' '14 withthe' passage 11, "while '-a secondbore 18. connects the-valve outlet to the threaded countenbdre '19 "extending: through the top surfiae'oflthehandlennitl Forwarder this the split lug 20 provides'foi:inountirigthe hingef'pinfor trigger 21 positionedto 'iengag'egthe' exposed lioifwarcl end of. valve stein"15"andpressJhe valveopen when the trigger is s ueezed;

A plate 22 is mounted. against the top of the handle and held in position by means of flange nut 23 screwed onto plug 24 engaged in the threads of the counterbore. Suitable means such as the downturned rear flange hold the plate against relative rotation on the top of the handle and augment the frictional engagement of the flanged nut. The plug 24 may have a suspension ring 25 provided at its upper end for hanging the gun if desired. Longitudinal passage 26 in the plug connects to the handle passage 18. Formed integral with plate 22 or attached thereto by screws or rivets, as shown, is the tubular forward projecting stem 28 of the principal unit of the gun. This extends a convenient distance beyond the trigger so that the fluid reservoir later to be described will not interfere with the operators finger on thetrigger. This extension 28, forming part of a pin and socket connection, is bored from its outer end toward the handle to provide a uniform diameter bore 29 having a pin 30 extending transversely thereof adjacent its rear end.

The enlarged outer end or head 31 on thestem has a cylindrical outer surface to receive the fitting 32 shown in all three figures. This latter is a thick' roughly triangular plate bored to fit closely over the surface of the head 31 and adapted to be mounted thereon and held in position by means of a set screw or the like, such as shown at 33 in Fig. l, threaded into a bore in the fitting and arranged to engage the surface of the head to lock the two in proper position. Alignment is effected conveniently by having the inner end 34 of screw 35 which is threaded into a diagonal bore in the fitting extend closely through a non-threaded opening properly oriented in the head 31. This screw 35 has a large knurled head for a purpose which will later appear;

In vertical alignment withthe bore 29 the fitting is provided with a vertically disposed slot 37 having'parallel side walls providing a relatively close working fit for the metal tube 38 or jet whichextends therethrough. This tube is provided with a suitable fine'bore shaped and sized to regulate the issuing air used for atomizing the liquid. The rear end of the jet behind the fitting 32 is either integral with, threaded or otherwise attached to a slightly flexible tube 40, as by means of a fitting 41. This tube 40 has its rear end enlarged and threaded for reception in a bore 43 formed laterally in the plug 24 and intersecting the bore 26 therein. In this manner air is conducted to and'through the jet whenever the trigger is gun. The second or liquid unit may be provided in any desired number, each complete, as now about to be described. Such a unit includes a mounting stem or plug 50 adapted to have a close sliding fit in the bore 29 in the end of the stem or stock 28 of the air unit of thegun. The rear end of this stem is transversely slotted as at 51 to closely fit over the pin 30 to insure against relative rotation of the units when the stem is inserted the proper distance. t

The stem or plug 50 is preferably formed integral with head 52 having a passage 53 therein normal to the plug axis. The upper end of 53 receives a threaded fluid nozzle 54, which has a suitably calibrated bore 55 to pass the desired quantity of liquid for the spray The nozzle is of such a height as to have its bore terminate within the range of adjustmentof the axis of the jet tube. The lower end of passage 53 threadedly receives the liquid pickup tube 58 which depends therefrom. It is of such a length as to reach substantially to the bottom of the desired size container, such as 60, whose upper edge is threaded as at 61 ,to engage into the threads of the skirt of vented and centrally perforated cover 62 mounted on the externally threaded lower portion of the head 52 and clamped between collar 63 engaging its upper surface and the nut 64 its lower surface.

This liquid unit is complete as just described and can be quickly mounted or dismounted from the air unit by manipulation of the screw 35 and insertion or withdrawal of the plug from the socket. The act of assembling the parts insures proper vertical alignment of the axis of the liquid nozzle. and its horizontal relation to the jet tip to change the character or density of the spray is regulated by the amount the plunger is inserted in the socket. When the proper position is found screw 35 is tightened. Further adjustment of the character, shape and the like of the spray is effected by manipulation of the screw 46 which regulates the vertical height of the horizontal axis of the air jet in relation to the tip of the liquid nozzle.

In use, the liquid desired to be sprayed is placed in one of the containers 60 and the plug of the unit inserted in the socket of the air unit of the gun and proper adjustments of the relative positions of the nozzle and jet made as just described. Thereafter the gun is used in the normal manner. Should a change in color, consistency, material or the like be desired a second liquid unit containing the proper material may be instantly substituted without requiring any cleaning of parts whatsoever. simple rubber or cork stopper fitted over the nozzle 54 of the removed unit will serve to prevent evaporation and hardening of the material in the fine bore 55 of its nozzle. Obviously materials of different consistency will be placed in containers having nozzle bores of proper caliber. The

air unit of the gun is never contaminated with any liquid and does not require "cleaning. The containers can be shifted so quickly that high volatile paints already sprayed on a surface do not have time to dry before a second color, which it is desired to blend with them, is ready for application, whereas with the old type of gun the time necessary for cleaning the containers, eduction tubes and the like precluded this type of operation without using two complete guns and then there was the opportunity for paint in the first one used to harden in the nozzle and tubes before the operator finished with the second and got around to cleaning it.

The gun of the present invention is simple in construction, low in cost, simple to operate and produces just as good results as the more complex and costly guns which cannot be used for a new color or material without time consuming cleaning.

I claim:

1. In a spray gun, in combination; an air control unit comprising a handle having an air passage therein, a spring closed valve in said handle to control said passage, a trigger for opening said valve, a forward extension from said handle, an air jet supported by and substantially parallel to said extension, flexible conduit means connecting said jet to the valve controlled portion of said passage; a self-contained spray-liquid unit comprising support means removably interengaged with said forward extension'and connectingsaid units mechanically, a nozzle carried by said support means with its axis substantially normal to the axis of said jet, said nozzle being positioned just below the jet axis for spraying, an eduction tube carried by said support means and connected to saidnozzle, a container cover carried by said'support means and a container for spray liquid removably carried by said cover in a position housing said eduction tube.

2. The spray gun combination as claimed inclaim l in which means is provided to'adjust the said air jet on said extension in the direction of the axis of the said nozzle to regulate the character of the spray pattern.

3. The spray gun combination as claimed in claim 1 in which said support means is interengaged with said forward extension along an axis generally in the direction of the axis of said air jet for adjustment to regulate the character of the spray pattern.

4. The spray gun combination as claimed in claim 1 in which means is provided to relatively adjust the said air jet and nozzle in the direction of the axis of the air jet to regulate the character of the spray pattern.

5. The spray gun combination as claimed in claim 2 in which means is provided to relatively adjust the said air jet and nozzle in the direction of the axis of the air jet to regulate the character of the spray pattern.

6. The spray gun combination as claimed in claim 1 in which the interengaged means comprise parts relatively slidable in the general direction of the axis of the air jet whereby the tip of the latter may be advanced or retracted from the axis of the nozzle.

7. A spray gun comprising an air unit and a connected spray liquid unit selected from among a plurality of spray liquid units of difierent characteristics each adapted for use alone with the air unit: said air unit comprising a handle, an air jet supported by said handle, means to de liver air to said jet, and one part of a plug and socket connection having its axis substantially parallel to but below that of the jet; each spray liquid unit comprising a container for spray liquid, an eduction tube extending into said container, a nozzle of one of several different calibers connected to said eduction tube, the other part of said plug and socket combination being mounted on said container with its axis substantially normal to that of the nozzle; said plug and socket connection parts being so disposed in relation to the jet and nozzle that the axis of these elements substantially intersects at nearly 90, and means on said handle to adjust the height of said jet above said noule.

8. The spray gun of claim 7 in which said connection parts are offset from the axis of the jet, means to prevent relative rotation between the gun units, and means to clamp the units throughout a range of plug and socket overlap to adjust the jet toward or from the nozzle axis.

9. The spray gun of claim 7 in which means is provided to effect relative adjustment of the air jet and nozzle in the direction of the axis of the nozzle to change the spray pattern.

10. The spray gun of claim 7 in which said socket is attached to project from said handle, a fitting adjacent the remote end of said socket having a vertical slot therein through which said jet extends, a spring urging said jet toward the top of said slot and a screw threaded through the fitting above the slot and having an end engaging the jet to adjust its position against the thrust of the spring.

11. The spray gun of claim 10 in which the fitting has a threaded opening remote from the slot, an extension of said opening in the socket wall and a screw engaged in said opening to secure the plug in adjusted position in the socket.

References Cited in the file of this patent UNITED STATES PATENTS 609,010 Comstock Aug. 16, 1898 1,169,558 More Jan. 25, 1916 1,541,794 Costa June 16, 1925 1,743,292 Tittemore Jan. 14, 1930 2,550,404 Chasan Apr. 24, 1951 FOREIGN PATENTS 324,147 Great Britain Jan. 23, 1930 49,545 Norway Oct. 9, 1930

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