US2867476A

US2867476A - Spray gun

Info

Publication number: US2867476A
Application number: US588475A
Authority: US
Inventors: John F Siefen
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-05-31
Filing date: 1956-05-31
Publication date: 1959-01-06
Anticipated expiration: 1976-01-06

Description

J. F. SIEFEN SPRAY GUN Jan. 6, 1959 5 Sheets-Sheet 1 Filed May 51, 1956 INVENTOR. JOHN F. SIEFEN J. F. SIEFEN Jan. 6, 1959 SPRAY GUN 3 Sheets-Sheet 5 Filed May 51, 1956 INVENTOR. 'JOHN F. SIEF'EN United States Patent-( 2,367 476 SPRAY! GUN 01 1 s sf nrp tmit, M ch- Applicatiou;May 31;1 956; Serial :No.. 588,475v

(c m-s6) My-inventio'n relates to anew.v andtuseful improvement in a spray gunforasp'raying.bufiing compounds, paints; and/ or likematerial in anatornizedrstate.

Spray guns have been developed;which aretcommonly1 referredto as beingiautomatically operated These auto matic spraynguns are of two general vclasses, butimboth:

classes mechanical or; electrical aircontrolsnare, used;

which are set at an externalpoint generally several feet from the spray; gun. quires acertain length of time, from a ira'ctionvof at This ista disadvantageast it re-HJ secondto two seconds, for the, air.totravellfromthe;

external controlstovthe outlet nozzle, of, thenspraylzgun;

when starting-to spray, and,- als o, ittrequires acertain; length of time-to, exhaust the air to the stop-9ft: point; whenstopping a spraying operation. These ttypes-qofn guns are generally recognized as having; certain idisad-l vantages.

1 ype-o heaforemen io edsprayeuns equi e wo air-hoses to be led to ,the spray gun. Oneqof these ir hoses vfurnishes: air iat anorrnalhigh pressure tomQYQ, apiston whichtopens antinternal valve so as to permit air from a secondair hose tqbe deliveredthroughpas sages in the body to theair cap. The second air hose is used fordelive ing atomiz ing airto atomize; or breaig, into small pa'rtieleethegnaterial being sprayed The p ton, after traveling a sh r t distance opens a needle valve allowing thesprayed n'iat erial to pass through the fluid, tip

A. second broad classifi cationof spray gunsomjhe, market today uses onef air hose so that thesupply of air regulated atan eiiternal valve, moves; a piston ort dia-,,' phragm to. open the needleavalve, the body of thesplray gun this same supply of ai 1s ,used; to atomize'the spray material. This type erally has a spattering of end of each operation which. is especially noticeable at-1 the end of the operat on This is due to thegneedle valve: opening beforenormal atomizing air. pressure has been; built up'at the air cap and,' on' closing, the atomization, pressure at the cap drdpsbeforeithe needle closes The present invention'has as its object the avoidance of these difficulties andvthe, provision of a spray so,

arranged and constructed so that no external aipvalve. to control the air flow is' required as the air control valve is madeas a part of the gun itself. Y Another object of the invention istheprovisiont ofi a spray gun of this cl'ass having a'nair control valve adaptd: tofprovidesubiantially instantaneous opening and clos ing of the valve, atth ebeginning and ,en-d ofwthe operation; Another object of the invention, ,is 3 the provision, of, a spray guu his WP h in a n'unde Proper; pressure for atorniz'atioii' s always present in the, gun so, that the disadvantages referred toflas t o. the sprayed ma; terial maven i Anni 1? Spray, an i i l mifv rgr't' pact.

'," 1. jb nialei r f cin enamia ighly s iqi t in u e a d. ht ndv m Thr u htpass e tin t of the invention is v the provisiongoh a z fit u ri nr the, Sprayat t e inn n aa lz 2,867,476 Patented Jan. 6, 1959 ice Other objectswill appear hereinafter.

It is recognizeduthatvarious modificationstand changes may. be made in the v details of the structure illustrated without departingmfrom theinvention, and,it:is iutendeda that-the-prsent disclosure shall be consideredito: be-.but; the preterrediembodimenu Forming. a. PBIZti'OfzrthiS application aretdrawings ain -i which, n 5

Fig; la'isla side;elevational viewflof the invention;;

Fig.=2-.-is an .endzelevational aviewt'of; the:.invention; I.

Figi 3 'ista: longitudinal central S6Cti0IlBl23ViBW nOfL-thQQL invention showing the control parts in one-position-gt.

Fig. .4-is a view.- similar to Fig. 3 :showing the :control parts in another position;

Fig. 5 is-va fragmentarysectional.view; taken onitlinea .'Of Fig. .31. a

In, thedrawings I havetindicated the, spray. guntlasu. comprising, a bo y 15..:hav-ing a, chamber 16 at the; for-H. ward? end vthereofi communicating through the passagealT with, a fitting -18ntowhich'. a, conduit; maybe; attached; for delivery; Qfi'vthevspray, fluid into theufchamberhlfig Threaded into the, end of the body is, a nozzle. ,19. having; an outlet; opening ztl and hollow to provide a comparts; dap ed, o: ngage-.1 at; it ndf o lose-w the. outlet; pe n 2.04. t 1 secnred onthe end of the-body 15 by; means of a collar; 4 atai 923; hav pa g s 2.5 rme therein; ommu ic tin i ht he utl passag s udal o. QI Ih: s Passa es-M do nwar ly. hrough; e, gr oves 74-1 formed on the conical end 75 of the= -nozjz le,1 9;, and outf; ward rl nou h hez nnu art pas a aro nd the-outlet; sleeve or terrninus zila qof thenozzle- 12; The-air under pressure emits through; passage ,201; 1 to atornizo; thell flu id whi hernits fronnopening Zilfllld emits through; passages 2d :t o forrn or shape this atomized fluid stream A nippl e 27; is; adapted for being connected to anair hose, so Lthattheair under pressure may be; delivered into;

the internal air-passages 28 into tthet cylinder ,29,at; one; sideoftthe piston mr Thi$ P Qn- 3tl isprovided with; a hub .,31;o n{, whi h is .threaded atretainen 32; wh-ic is adaptedto serve as a fi i fl t i hi hzwo qsa s; with the send, face ot the; piston-hr); retainthe sealing ring 33 in: engagementwith the:bottom of the cy-linder;

29, so as to close coinrnunicatjonlof the space-1,34, which,

surrounds the retainer fill with thetcylinder-29 jThep 0 type. Secured on;theQpposite.;end of the, ho dy 15. 19;

7 means pfthe collar 35isjthefsupport or-retainerfia which islthreaded onto ,a,

The cylinder lfl comrnunicates with the atmosphere by; the following"described conduit means. A chamber 39} is formed in the retainer- 36 and lco-mmunicatesithrough g the passage 40 with the compartment. 41;; This corni-I, partrnent :41 is, adapted ito communicate. ethrough uthet passage's eiz and 43 withthe, atmosphere.v w

' A valve head 44 is projectable into the .charnber;. 41 and this .valve head carriesat its end a composi tiorn disc valve 45 which serves to engage loverv the passage;

42" and close thersarn'e, so that the chamber; 41, i 'theu no longer in cornrnu ieationv with the atmosphere, A, bead146 on the valve head 44, en gages one end of,.;the l' t n 1 he a ei fw irh a f l mi a w seat in' the fi ting 3 7 This valve .h e ad .44; is com te of "the solenoid coil I 49 .which ni ay e; electrically connected to ,asourcetof energy by; means} ofgthe, cable QSQ;

Formed in piston 30 ,is.,,a; recess 51;1 in which isg,

3. slidably mounted a pair of spaced apart integral annular flanges 52 and 53, carried by the stem of the needle valve 22. A sealing ring 54, preferably one of the type, is positioned between said flanges 52 and '53.v

Acoil spring 55 engages at one end the flange 53 and at its other end the bottom of the chamber or compartment 39. Embracing this coil spring 55 is a coil spring 56 which engages at one end the bottom of the compartment or chamber 39 and at its opposite end in a recess. 57 formed in the face of the piston 30.

The space 34 surrounding the retainer 32 is in communication with a plurality of passages 58 formed in the body 15. These passages 58 communicate With the space 59 which is between the end of the body and the aircap 23.

In use the spray fluid would always be under pressure, so that in the chamber 21 spray fluid would be ready for emission through the outlet opening upon opening of the needle valve 22. This needle valve- 22 passes through a packing 60 which may be packed by the gland 61 which is accessible through the opening 62 formed in the body 15.

gland is provided with a head 63 for the reception of a suitable wrench. As shown in Fig. 3, the needle valve 22 also projects through a sealing ring 64, preferably of the 0 type. The sealing ring 64 is seated around the needle 22 in a recess in the face of a collar 64a which is mounted in the recess 64b in the body 15. The sealing ring 64 is operatively retained in the collar 64a by means of the collar 64c which is threadably mounted in the body 15. The sealing ring 64 functions as an air seal to prevent air leakage around the needle valve 22 from the chamber 34.

When the spray gun is set up for use, compressed air under pressure will flow through the fitting 27 and the passage 28 into the cylinder 29, at the right side of the piston 30, as viewed in Figs. 3 and 4, and through passage 30a in the piston 30 to that portion of cylinder 29 to the left of piston 30. As communication of the cylinder 29 at the left of piston 30 with the atmosphere through

passages

42 and 43 is closed no movement of the piston to the left takes place. Bleed passage 30a is formed through piston 30 so that the air pressure on both sides of the piston 30 is equalized.

Consequently, the spring 56 will retain the piston 30 in a closed or at rest and, the pressure of the spring 55 will retain the needle valve 22 in a closed or at rest position.

A suitable switch would be interposed in the cable 50 and upon closing of this switch and the energizing of the solenoid 49, the armature 48 would move to the left, as shown in Fig. 4, so that the composition disc valve 45 would move into an opening position relative to the chamber 41 and thus permit communication of the cylinder 29 at the left side ofthe piston 30 with the atmosphere, through

passages

42 and 43. This would unequalize the air pressure on opposite sides of the piston 30 so thatjsaid piston would move to the left as shown in Fig. 4, so as to establish communication between the cylinder 29 and the space 34 around the retainer 32. Therefore, the'air in the cylinder 29 would pass through the space 34 and through the passages 58 to the

passages

59, 73, 74, 25, 26 and 20b. After the piston 30 has moved to the left a short distance it would pick' up and move the needle valve 22 to the left. In this movement there would be a lag in said picking up effect,on account of the gap 51, so that the sealing ring 33 would move to an open position before theneedle valve 22 moved to open position. Thisflag would be of very short duration, but, before "tli'e"sp ray fluid would issue from the opening 20,fatomizingffair would be issuing through the passages-"20bnand 26. Consequently, any fluid emitting through the outlet 20 Willbe immediately'subject'ed to the'air'actionf The packing 60 functions as a spray fluid seal to prevent leakage from the chamber 16. This position as shown in Fig. 3,

' means communicating In stopping the operation, upon deenergization of the solenoid 49, the core 48 would be moved to the right in response to the spring presure 47, thus cutting ofl? coinmunication of the cylinder 29 with the atmosphere. The air pressure on opposite sides of the piston 30 would then build up to equal pressures, and the spring 56 would force the piston 30 to the right. At the same time, spring 55 would force the needle valve 22 to the right. After piston 30 and needle valve 22 have moved to the right a distance equal to the travel distance between the open position of the needle valve 22 and the closed position of said needle valve, the delivery of spray fluid would cease. Piston 30 continues moving to the right, on account of gap 51, to its closing position, cutting off communication of cylinder 29 to space 34 by sealing ring 33. Thus, atomizing air would cease to flow through

passages

58, 59, 73, 74, 25, 26 and 20b. This time lag on stopping'the operation would assure that all spray fluid would atomize, as the spray fluid will cease before atomizing air would cease. rest or closed position.

In this manner, the various disadvantages and difliculties would, therefore, be overcome and a substantially instantaneously controlled spray would be accomplished.

As shown in Figs. 4 and 5, formed through the body is a passage 76 through which may be extended a stud 77 which threads into a stem'78 of a yoke embodying :the separated

arms

79 and 80 of Fig.v 2, which may be drawn together by a suitable screw 81 so that the

arms

79 and 80 may clamp against a suitablesupport or rod which may be projected through the opening 82, thus affording a means of mounting the gun in stationary position when desired.

What I claim is:

1. A spray gun of the class-described, comprising: a body; an outlet nozzle mounted on one end of said body and havin'gan outlet opening for the emission of liquid therefrom; a cylinder on the opposite end of said compartment with the atmosphere; a valve in said compartment for closing communication between said passages; a piston slidably mounted in said cylinder; a spring in said cylinder normally urging said piston in one direction; an inlet port in said body communicating with said cylinder at one side of said piston for conduct ingair under pressure thereinto, and moving said piston. in the opposite direction against the compression of said spring; an inlet port in said body for conducting liquid under pressure into said body for emission through the outlet opening of the said nozzle; a rod in said body having a needle valve at one end for engaging said nozzle op osite end extending through said piston;. and, an. enlargement on said rod engageable with said piston, upon movement of said pistonagainst the compression of said spring a slight distance for engaging said needle valve and moving said needle valve to open position.

2. A spray gun of the class described, comprising: a body; an outlet nozzle mounted on one end of said body and having an outlet opening for the emission of liquid therefrom; a cylinder on the'opposite end of said body; a retainer mounted on said opposite end of said body and forming a closure for said cylinder and having conduit said cylinder with the atmosphere; said conduit means including a compartment, a first passage communicating said compartment with said cylinder, and a'second passage communicating said comment for closing communication a piston slidably mounted said The spray gun is now at and closing said. outlet opening; said rod at its in said cylinder normally-t urging-said pistonfin; one

direction; an inletport in saidv body ;cornmunic ating with said cylinder at one vside of said piston for. conducting air under pressure thereinto, and moving said piston in v the opposite direction against the compression of said first spring; an inletflport in said bodyQfor conducting liquid under pressure into said body for; emission through i the outlet opening of the said nozzle ,a rod in saidgbody havinga needle valve at one end for engaging. said nozzle and closing said outlet opening said rod at its opposite I and having an outlet opening for the emission of liquid 7 therefrom; a cylinder on, the opposite; end of said body; a retainer mounted on said opposite endof said body and forming a closure for said cylinder and having conduit means communicating said cylinder With the ;atmos-.

phere; said conduit means including a compartment, a first passage communicating with said compartment with said cylinder, and a second passage communicating said compartment with the atmosphere; a valvein said compartment for closing communication between said passages; 7

a piston slidably mounted in said cylinder; a first spring 2 fj ld. r s s ri having a needle. valve at one end tor engaging rsaid -no zle and closing saidoutlet opening; said than; site vend extending through said piston; an nlarg'ement on saidrod engageable with saidvpiston uponrniovemel H of said piston against the compression of said first spring a slight distance for engaging saidneedleyalveandln o ing said needle valve. to open'position;ia seeondspring extending into said cylinder andengaging at one endQs'aidQ. retainer and at the opposite end said'enlargement on sa' rod for normally urging said needle .valve tinto closing position; said piston-havinga passage fornred. the through for effecting'equalizing of lair 'rjessure I site sides of said piston; and, a solenoid in. saidretainer for, upon being energized opening said first n med eval and establishing communicjation of sar cyl der at o side of said piston with the atmosphere,

5. A spray gun of the 'classdeseribed, cornprisingzoa body; an outlet nozzle mounted. on one end,.of

and having an .outlet opening' ferr the lemiss io n of -ligui therefrom; a cylinder on the opposit e end-pf said body a retainer mounted on'said opposite end oflsaid body an forming a closure for said cylinder and having pondui means communicating saidcylinder with the atmosphere said conduit meansinclu'ding. ai'cornpartment a firs passage communicating said compartrnent with said cylinder, and a second passage communicating said vcompartment with the atmosphere; await/ .in .said compartment;

in said cylinder normally urging said piston in one.di-

rection; aninlet port in said body communicating with said cylinder at one side of .saidpiston for conducting airunder pressure thereinto, and moving said piston in theopposite direction against the compression of said firstispring, an inlet port in said body for conducting liq-. uid under pressure into said body, for emission through the outlet openingof the saidnozzle; a rodin said body having a needle valve at one end for engaging said nozzle and closing said outlet opening; said rod at its opposite end extending through-said, piston; an enlargement on said rod engageable withsaidpiston, uponmovement of said piston against the compression of saidfirst spring a slight distance for engaging said needle valve and moving said needle valve to open position; a second spring extending into said cylinder. and engaging at one end said retainer and atthe opposite end said enlargementon said rod for, normally urging said needle valve into closing position; and, said piston having a passage termed therethrough for effecting equalizing of air pressure on opposite sides of said piston.

4. A spray gun of the class described,'cornprising: a body; anoutlet nozzle mounted on one end of said body and having an outlet openingfor the emission of liquid therefrom; a .cylinder on the opposite end of said body; a retainer mounted on said opposite end of said body and forming a closure torsaid cylinder and having con duit means communicating said cylinder with the atmosphere; said conduit means including a compartment, a first passage communicating said compartment with said cylinder, and a segond passagecommunicating saidcom partment with the atmosphere; a valve in said compartment for closing communication between said passages; a piston slidably mounted in said cylinder; a first spring in said cylinder normally urging said piston in one direction; an inlet port in said body communicating with said cylinder at one side of said piston for conducting air under pressure thereinto, and moving said piston in the opposite direction against the compression of said first spring; an inlet port in said body for conducting liquid under pressure into said body for emission through the outlet opening of the said nozzle; a rod in said body for closing communication betweensaid passages; a piston slidably mounted in said cylinderfya first springdn said cylinder normally urging said piston in onedirection; an inlet port in said body communicating iwith said cylinder at one side of said piston for. conducting. an under pressure thereinto, and moving said piston in the ppp'osite di rection against the compressionfof'said firstssp ring; an inlet port in said body for conducting lliquid under pres-, sure into said body for emissiontlirough the outlet opening of the said nozzle; a rod in said body having a needle valve at one end for engaging said nozzle and closing sai Y 1 outlet opening; said rod .at its opposite end extending through said piston; an enlargement on said rod engage; able with said piston, upon movement of said. piston against the compression of said ffirst fspring a slight dis-t tance for engaging said needle valve and moving said needle valve to open. position;,a second spring extending into said cylinder and engaging at one end said retainer and at the opposite end said enlargement on said rodjfo normally urging said needle valve into closing position; said piston having a passage formedtherethroughfior effecting equalizing of air pressurefon opposite: sides of} said piston; a passage in said body for deliveringair from said cylinder to and a'ro'un'd said nozzle; and,v avalve on said piston for controlling con imunicationof saidllast named passage with said cylindefandmovable to open position upon movementlof saidipiston againstfme cornpression of the first spring bearing fjagainstfthe same; I

6. A spray gun of the class described; compris'in'gz a 3 body; an outlet nozzlemounted .onone'end .of saidbody andhaving an outlet opening for the emission of liquid therefrom; a cylinder on the opposite end of said body; a retainer mounted on .said opposite end of vsaidflbody f and forming a closure for said cylinderan'dhav'ing con- 1 duit means communicating' said cylinder with the 'atrnos phere; said conduit media s includingiaeornpartrnent a first passage communicating said department's/ahead cylinder, and a second passage communicating said compartment with the atmosphere; a valve in said compart ment for closing communication between said passages; a piston slidably mounted in said cylinder; a first spring in said cylinder normally urging said piston in one direction; an inlet port in said body communicating with said cylinder at one side of said piston for conducting air under pressure thereinto, and moving said piston in the opposite direction against the compression of said first spring; an inlet port in said body for conducting liquid under pressure into said body for emission through the outlet opening of the said nozzle; a rod in said body having a needle valve at one end'for engaging. said nozzle and closing said outlet opening; said rod at its opposite end extending through said piston; a recess in said piston having an inner end face; an enlargement on said opposite end of the rod and being seated in said recess in spaced relation from said recess end face when the needle valve is in the position to close the outlet opening; said enlargement on said rod being engageable with said recess end face in said piston, upon movement of said piston against the compression of said first spring a slightrdistance for engaging said needle valve and moving said needle valve to open position; a second spring extending into said cylinder and engaging at one end said retainer and at the opposite end said enlargement on said rod for normally urging said needle valve into closing position; said piston having a passage formed therethrough for effecting equalizing of airpressure on opposite sides of said piston; a passage in said body for delivering air from said cylinder to and around said nozzle; and, a valve on said piston for controlling communication of said last named passage with said cylinder and movable to open position upon movement of said piston against the compression of the first spring bearing against the same.

7. A spray gun of the class described, comprising: a body; an outlet nozzle mounted on one end of said body and having an outlet opening for the emission of liquid therefrom; a cylinder on the opposite end of said body; a retainer mounted on said opposite end of said body and forming a closure for said cylinder and having conduit means communicating said cylinder with the atmosphere;

said conduit means including a compartment, a first passage communicating said compartment withsaid cylinder, and a second passage communicating said compartment with the atmosphere; a valve in said compartment for closing communication between said passages; a

solenoid connected to said valve for controlling the same and upon being energized, moving said valve to an open position for establishing communication between said passages; a piston slidably mounted'in said cylinder; a first spring in said cylinder normally urging said piston in one direction; an inlet port in said body communicating with said cylinder at one side of said piston for conducting air under pressure thereinto, and moving said piston in the opposite direction against the compression of said first spring; an inlet port in said body for conducting liquid under pressure into said body for emission through the outlet opening of the said nozzle; a rod in said body having a needle valve at one end for engaging said nozzle and closing said outlet opening; said rod at its opposite end extending through said piston; an enlargement on said rod engageable with said piston, upon movement of said piston against the compression of said first spring a slight distance for engaging said needle valve and moving said needle valve to open position; a second spring extending into said cylinder and engaging at one end said retainer and at the opposite end said enlargement on said 1 rod; for normally urging said needle valve into closing position; said piston having a passage formed there-,

through for effecting equalizing of air pressure on oppdsite sides of said piston; a nozzle cap mounted on said body and embracing said outlet nozzle and having air passages formed therein for discharging air outwardly around said outlet nozzle in the path of flow of liquid passing through said outlet nozzle; a passage in said body for delivering air from said cylinder to the passages in said nozzle cap; and, a valve on said piston for controlling communicationof said passage in said body with said cylinder and movable to open position upon movement of said piston against the compression of the first spring bearing against the same.

8. A spray gun of the class described, comprising: a body; an outlet nozzle mounted on one end of said body and having an outlet opening for the emission of liquid therefrom; a cylinder on' the opposite end of said body; a retainer mounted on said opposite end of said body and forming a closure for said cylinder and having conduit means communicating said cylinder with the atmosphere; said conduit means including a compartment, a first passage communicating said compartment with said cylinder,

and a second passage communicating said compartment with the atmosphere; a valve in said compartment for closing communication between said passages; a solenoid connected to said valve for controlling the same and upon being energized, moving said valve to an open position for establishing communication between said passages; a piston slidably mounted in said cylinder; a first spring in said cylinder normally urging said piston in one direction; an inlet port in said body communicating with said cylinder at one side of said piston for conducting air under pressure thereinto, and moving said piston in the opposite direction against the compression of said first spring; an inlet port in said body for conducting liquid under pressure into said body for emission through the outlet opening of the said nozzle; a rod in said body having a needle valve-at one end for engaging said nozzle and closing said outlet opening; said rod at its opposite end extending through said piston; a recess in said piston having an inner end face; an enlargement on said opposite end of the rod and being seated in said recess in spaced relation from said recess end face when the needle valve is in the position to close the outlet opening; said enlargement on said rod being engageable with said recess end face in said piston, upon movement of said piston against the compression of said first spring a slight distance for engaging said needle valve and moving said needle valve to open position; a second spring extending into said cylinder and engaging at one end said retainer and at the opposite end said enlargement on said rod for normally urging said needle valve into closing position; said piston having a passage formed therethrough for effecting equalizing of air pressure on opposite sides of said piston; a nozzle cap mounted on said body and embracing said outlet nozzle and having air passages formed therein for discharging air outwardly around said outlet nozzle in the path of flow of liquid passing through said outlet nozzle; a passage in said body for delivering air from said cylinder to the passages in said nozzle cap; and, a valve on said piston for controlling communication of said passage in said body with said cylinder and movable to open position'upon movement of said piston against the compression of the first spring bearing against the same.

References Cited in the file of this patent Carr May 15, 1951