US 2626122 A
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Jn. 20, 1 953 w. I AMMIMANl 2,626,122
SPRAY GUN VALVE Filed July 3, 1951 f7 .16 i4 j Je 9 INVENTOR LEWIS WTIAMMIMAN.
ATTORNEY Patented `an. 20, 1953 UNITED, STATES vPATEIW OFFICE 2,626,12z sritiY GUNjvALvEI Lewis W. Lammiman, Toledo, Ohio', assign'or to The De VilbissCompany, .Toledo,fhio, a corporation of Ohio Application "J uly 3, 19512', SerialeNo. 235,013
lthe air jets is reduced or increasedby closing orv opening movement of thevalve.
As usually constructed this valve Vhas a vtapered 'inner end which seats Within the air passage, a threaded shank by which it is rotatably mounted,
and an external knurled head' for manual adjustf ment. In'order to provide a' broad range of adjustment a relatively'fine thread is utilized. It is thus possible to set the valve for a very particular ow of air that will shape the spray pattern 'most suitably for a certain type of surface.
In many spray hishing operations the character of the products being coatedis such that a single lwidth of spray vis satisfactory for all purposes. However, in otheriinishing'proeesses, there are occasional surfaces of restricted area, for which a wide spray pattern, Vselected for". a major part of the coating work, is not suitable.
vSince*excessive 'Waste'frm overspra'y orit'oo heavy a vcoatingresults from the Iuse of too'wide a spray pattern, under 'such circumstances it is desirable for the operator to temporarily screw the spray width valve at least part way towarda closed position. He must subsequently Acarefully openy it again to the predetermined setting considered best for the predominant type'of surfaces. Because of thev ne thread on the valve shank, considerable rotary movement is' required inthis closing and opening of the valve and valuable time is lost in the accompanyinginterruption of thel sprayingoperation.
The purpose of my invention is 'the provision'fof :af valve structure-for controlling theY air deliveredto attening jets in a spray gun in `which thefadvantage of close adjustment is retainedfand which in addition has mean-s'for `easy and rapid manual closing and self-opening movement of the valve with stop means limiting the opening movement to the valve position previously selected for normal use.
This improved action. is secured by mounting the valve for both gradual vthreaded adjustment and independent sliding axial movement. This is accomplished by having 'an unthre'aded valve shank fitting snugly' for relative'axial'movement within an" -exteriorly'f threaded-brota',`1',"ableA Tsleeve` In order to secure spray pat- (Cl. 25k-2l the exterior end of sleeve 22 is the knurle'dhead andproviding between the valve shank andfsle'eve a longitudinal slot and pin connection'.
An embodiment of'my invention is hereafter described in detail andv illustrated in the accompanying drawings in which- Figure 1 is a'central'vertical longitudinalse'ction of a spray gun-incorporating the-invention;
Figure 2'is an enlarged longitudinal section of the valve assembly taken on the line 2--2 of Figure 1;
Figure 3 is'ra perspective-viewer the horse Shoe 'lockl washer which holds ythe'- packing spring'4v in place; l
Figure 4 is a perspective viewwith a portion broken away of the valve assembly fcasin'gl;
Figure 5 is a perspective view Vo'f the valve'position adjusting sleeve; vand Figure -6 is a sectional -viewv v taken oni the `line 6-6 of Figure l2 'through lthe valve Ishank'.
The spray gun of Figure l--is a'fc'onventional design Vto which my invention has'- beenadapt'ed. Ithas `a depending handle I` in which there isfan air supply passagev v21S The travels therethrough past air valve'f3'whichisA opened by. rearward movement of the"trigg`er llag'ainstl the extjeriorly extending ivalve spindle 5i The.V air. then hows upwardly.- from the val-ve chamber `through outlets. O-ne is a forwardly continuingpassage into the airv partitioning. inernlmer `I 0; The other outlet is* thef annular chamber lvl b'ehind'vthe 'member-1B. Theoutlet passage: yilis for air travelling'to `the'horr1s-l2-o'f the air cap I3 vto form opposed spray flattening'jets. The air from passage 9 reaches the horns by way of the encircling chambery Ill, 'a .series ofI ports I5 throughia flange of ttheinember I0; andhen'ce into annular chambeil behind the bores Il into the horns. .The outlet, chamber H is yfor 'primary' atomizing air vvliiclriV 'travels' forwardly'- through an "annular rse- "ri'es loi'passages I8 intothe spacef FQ'betWeen-.the
spray material tip 20 and theair cap' .|3. From here' the air flows vout the center oricef ofthe air'cap. in atomizing association withrthe spray material discharged' from' tip '20.
Into the rear end of bore 8 is threadedly mountedthe valve casing 2 I. Extending through the' casingr 2| and threadedlyv connectedy thereto for axial adjustment the valve sleeve 221. On
l2i! for manualturning and axial positioning of the sleeve: Throughthe sleeve 22 .extends the shank 24 o'fthe valvda-f.A 'Thershank has fi-'Mose but@'slid'abie'iitffwith the1=fsl`eeve.-v The valve 25 sitioned longitudinal slots 3l in valve sleeve 22.
A spring 32, lodged within the enlarged bore 26 of the valve sleeve 22, is compressed between the bore shoulder 21 and the forward end of the thumb button stud 30. Through the effect. of the spring thrust the valve shank 24 is yieldably held rearwardly in respect to the sleeve 22 to the ex.-
tent of movement permitted by the pin and slotv connection between the valve shank and sleeve. Accordingly the ends of the pin 29 are normally pressed against the rear ends of the slots 3 I.
Through the threaded engagement of the sleeve 22 with the xed valve casing 2| axial movement of the sleeve 22 is secured by manual turning of the knurled head 23. Because of the pin and slot connection between the sleeve 22 and the valve shank 24 and the effect of the spring holding the pin ends at the ends of the slots, axial movement of the sleeve varies the position of the valve 25 in respect to its seat. The amount of air reaching the horn ports is thus controlled and may bepredetermined to accommodate the type of surface being finished in respect to the width of spray desired. Y
When a narrow surface is to be coated and it is desired to momentarily reduce the width of the spray pattern from that selected for large surfaces the operator depresses the thumb button with the thumb of his hand actuating the spray gun and thus pushes the valve 25 toward its seat reducing theflow of spray flattening air from the horns. Under tension of the spring 32 which is temporarily overcome by the thumb pressure the valve is returned to its selected position when the thumb is removed. A spray of proper width is thus again delivered for coating the general run of work, as the return of the valve shank does not disturb the rotary position of the sleeve by which the preferred valve position was previously secured.
For a long period of coating surfaces of limited v4dimensions the valve 25 may be forced to its seat by turning sleeve 22 sufficiently forwardly. The length of the threads between the sleeve 22 and the casing 2l -is suicient to permit this action.
To prevent leakage between the sleeve and the valve casing, packing 33 is positioned therebetween. It is held against an inner annular ange 34 of the casing 2| by spring 35 which is held in compressed prelation to the packing by the horse-shoe lock washer 36. The latter is postioned in a groove 31. In order to lessen the twisting effect upon the spring 35 from rotary movement of the valve sleeve 22, a loosely mounted washer 38 is inserted between the end of the spring and locking washer 36.
From the preceding it may be understood that the slot and pin engagement between the valve .shank and sleeve in association with the spring 32 .and the threaded mounting of the sleeve provides means for both gradual adjustment of the valve shank and the surrounding sleeve is utilized in the preferred embodiment, it is realized that there are analogous structures which would serve as well. For instance a groove of suicient depth would function as electively as the slot. Then too, a pin or fiattened tongue could be feasibly substituted for the screw. It is not considered that such replacements would depart from the spirit'of the invention and that slot and screw as herein specified should accordingly be interpreted broadly.
Also, it may be well to point out that it is not essential that the slot be in the sleeve and the pin or screw be inthe valve shank as the reverse positioning would work as well. In addition, it may be observed that the valve shank could have a threadedengagement with the sleeve and the latter a slot and screw engagement with the rod without any loss in functions over the preferred form. For this reason the scope of this invention is not considered limited to a particular location of such engaging structures.
Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:
1. In a spray gun air valve, means providing an air passage, a valve seat within the for- Vward end of the passage, a valve mounted for axial movement toward and away from said seat, an interiorly threaded casing in fixed position at the rearward end of the passage, a freely rotatable hollow sleeve threadedly engaged within the casing, a shank integral with the valve and extendingl rearwardly through the hollow sleeve, a connection between the shank and sleeve formed by a pin and a longitudinal slot adapted to provide limited relative longitudinal movement between the shank and the sleeve, an annular shoulder on the shank facing forwardly toward the valve seat, an annular shoulder on the sleeve facing rearwardly away from the valve seat in opposing relation to said first shoulder, a spring compressed longitudinally between said shoulders adapted to thrust the valve shank and valve away from said seat to the limit of movement permitted by the pin and slot connection, a rearward exterior element onV the shank for receiving temporary manual pressure to thrust with straight line movement the shank and the valve in opposition to the spring thrust toward the valve seat, and adjusting means on the rearward portion of the sleeve for manual rotation and axial movement of the sleeve upon its threaded engagement with the casing to vary the normal position of the valve as determined by the limit of the spring thrust movement permitted by the pin and slot connection between the shank and the sleeve.
2. A spray gun valve as set forth in claim 1 in which the rearward exterior element on the shank has a hollow stud part into which the end of the shank extends, and the pin of the pin and slot connection extends transversely through the shank and stud part to secure the element to the shank with the ends of the pin extending further into slots in the'sleeve to form the pin and slot connection between the shank and the sleeve.
3. A spray gun valve as set forth in claim 1 in which the sleeve has a bore portion closely fitting the valve shank and a rearward enlarged bore portion, the rearward enlarged portion providing a housing for thev spring, and the shoulder ofthe sleeve against whichthe spring is com- LEWIS W. LAMIMIMAN.
6 REFERENCES CITED The following references are of record in the le of this patent:
UNITED STATES PATENTS Number Name Date Warter July 19, 1921 Peterson Dec. 19, 1933 Pellar Mar. 9, 1944 Peeps May 17, 1949