US1572509A - Pneumatic paintbrush - Google Patents

Description

Feb. 9 Y1926. 1,572,509

F. w. SCHNEIDER PNEUMATIC PAI NTBRUS H Filed March 25, 1923 2 Sheets-Sheet 1 Feb. 9,1926. 1,572,509

F. W. SCHNEIDER PNEUMATIC AINTBRUSH Filed March 23, 1925 2 sheets-sheet 2 /N VEN T0@ Patented Feb. 9, 1926.

UNITED STATES FREDERICK W. SCHNEIDER, 0F BALTIMORE, MARYLANMI), ASSIIGNOR TO PITTSBURGH PLATE GLASS COMPANY, A CORPORATION OF PENNSYLVANIA.

PNEUMATIC PAINTBRUSH.

Application filed March 23, 1923. Serial No. 627,118.

To all 'whom z' may concern:

Be it known that I, FREDERICK W.v SCHNEIDER, a citizen of the United States, and a resident of Baltimore, in the county of Baltimore City and State of Maryland, have made a new and useful invention in Improvements in Pneumatic Paintbrushes, of which the following is a specification.

The invention relates to pneumatic paint brushes or air brushes, as they are often termed. It has for its principal objects the provision of an improvedconstruction, (1) which can very readily be taken apart and cleaned; (2) in which the strain upon the hand in operating the two triggers is reduced, and the air trigger is operated in starting ahead ofthe paint trigger, and in stopping, after the paint trigger, without the exercise of conscious effort to secure this sequence; (3) having a simple form of air control with a minimum loss of pressure due to friction in the passage from the hose to the air nozzle; and (4) having a simple form of outlet head for securing the shift fromV a round spray to a flat one with the latter positioned either in a vertical or a horizontal plane. One embodiment of the invention is illustrated in the accompanying drawings wherein:

Figure 1 isa side elevation of the device.

Fig. 2 is a vertical section with o ne of the side plates removed.v Fig. 3 1s a slde eleva-` tion of the discharge head with the cap and securing nut removed. Fig. 4 is a plan view of the head. Fig. 5 is an end elevation of the head. Fig. 6 is a side elevation of the cap. And Fig. 7 is anen'd elevation of the 1Referring to the drawings, and particularly to Fig. 2, the princi-pal parts may be enumerated as follows:

- 1 is the discharge head provided with the air nozzle 2; 3 and 4 are side plates which fit over and enclose the air supply tube 5 and '.Air is supplied to the central nozzle l2 through the tube 5 and this supply of air is controlled from the valve 11 mounted for longitudinal movement in the connection 9 and yieldingly held in closed position by means of the spring 17. The valve 11 has a stem 18 which is grooved so that when the valve is moved to the rear, the air pass-es freely along the stem and into the supply tube 5. AMounted for longitudinal move,- ment in the tube 5 is the operating tube 19 which carries at its rear en'd a relatively thin metal vplate 20 so that the obstruction offered by this member to the flow of air through the tube is slight. This plate is adapted to engage the end of the valve stem 18 when the tube 19 is moved to the left. The sides of the supply tube are slotted, as indicated at 21, and through' these slotted sides projects a pin 22 carried by the tube 19 and adapted to be operated by the forked finger 23 at the upper end of the trigger 12. The arrangement, as above described, including the valve 11, tube 19 and plate 2O provide for a straightaway air passage from 'the connection 9 to the nozzle 2, so that the losses in pressure due to friction are re- Aduced to a minimum. Any leakage of air through the slots 21 is Slight, as the tube 19 has a relatively close fit in the tube 5.

The needle valve 13 which controls the How of the paint through the nozzle 24 is normally held forward by means of the spring 25 bearing at its rear end against the stuffing box 26 which constitutes a closure for the cylinder 27 carrying the valve. The vnozzle 24 is4 screw threaded into the end of .the cylinder 27 which permits of its endwise adjustment to bring the outlet end to proper position with res ect to the nozzle 2, such nozzle 2 being adjustable and being held in position by means of the screw 28. The triggers 12 and 1-4 are carried upon pins 29 and 30 secured to the side plate 3 so that when the side'plates are separate-d, the triggers may be readily removed. The stem ot the valve 13 is provided with a pair of nuts 31, one of which is a lock nut, which Serve to adjust the amount of lostl motion in thc movement of the trigger 14. The paint supply tube 6 is preferably Vof exible metal, screw threaded into the head at its forward end, as indicated at 32 and` threaded to the cononection 33 at its rear end as indicated at -The foregoing arrangement, includingvthe use of the side plates 2'and 3 provides a convenient arrangement for taking the device apart for cleaning or repair. In order to gain access to the interior of the device, all that is necessary is to unscrew the connections 9 and 10 and remove the clamping nuts 7 and 8 which leaves the side plates free to be removed. In order to prevent the supply tube 5 from being unscrewed at its forward end when the connection 9 is unscrewed, a sleeve 7a is shrunk onto the tube 5, such sleeve having fiat sides engaging the side plates 2 and 3, so that it cannot rotate. rIhe air supply tube 5 and paint supply tube can then very readily be unscrewed to give access to the air and paint nozzles and to permit the cleaning of the pipes in case they become clogged. The arrangement of the two triggers is also advantageous, as it reduces the strain upon the hand of the operator, as compared with those constructions in which the two triggers are operated by the fingers.` In the present device, the pressure of the palm or base of the hand operates the air trigger 12, while the pull of two of the fingers serves to operate the paint trigger. In operating these two triggers, it is desirable that the air trigger be ,operated first when the device is started and that the paint trigger be released first when the operation is discontinued. I have found that the pressure, as naturally applied by the operator upon the handle of the-device, and without conscious effort, gives this de sired sequence of operation. Pressure of the hand in starting the device first opens the air valve, after .which the pull by the fingers opens the paint valve, while in the rele-ase operation, the relaxing of the hand first releases the paint trigger and then the air trigger. The operation of the device. therefore, requires less'attention and skill than is the case in the type of apparatus where two finger' triggers are used.

The air nozzle construction willl be seen by reference to Figs. :3,to 7. Referring to these iigures,it,w1ll be seen that the air head is provided with a conical surface 35 provided with an annular oove 36 and with four branch grooves 37 eradin inward toward the center of the head rom the groove 36. The groove 36 is supplied with air through a pair of inclined passages 38. The'cap 15 is provided with an annular, con,

ical surface 39 adapted to. oppose and fit tightly against the annular surface 35 on the head. Leading from this surface are two passages 40 leading to the supplemental air nozzles 41. The cap. 15 is held in position agansththe head bymeansof the nut 16 which fits over the end ofithe'cap and has engagement with the threaded portiorr 42' of the head. When the cap is in a position of rotary adjustment such that theends of 40 over the ranch passages 37, air is sup-,

plied to such passages 40 via the groove 36 and the branch passages and the spray ofy paint, which would otherwise be round, is spread laterally, giving a fan spray. When it is desired Vto turn this spray 90, all that is necessary is to rotate the cap 9 0", bringing the inner ends of the passages 40 into alignment with the other set of branch passages 37. When the cap is in its desired position of adjustment, the nut 1 6` is tightened suficiently to prevent any accidental rotation of the cap. This forms a simple and convenient method of securing either a round spray, a vertical fan spray or a' horizontal fan spray, depending upon the requirementsl of the work. The parts constituting the head maybe easily taken apart for cleanlng purposes. In case paints of different degrees of lfluidity are used, paint nozzles similar to 24, but of different interior dimensions,may

be substituted, thus rendering the device capable of a wide variety of use. l

What I claim is: Y 1. In combination 1n a pneumatic air brush having a body portion, a paint nozzleor more of the fingers of such hand.

2. In combination in a pneumatic air brush having a body portion, a paint nozzle and an air nozzle arran ed in" operative relation, supply passages fieading to the nozzles, and valves for controlling said passages,

of a pistol grip for the body portlon, and a palr o f trlggers for operating the valves, the air contro ling trigger extending along the back of the grip, and operable by the pressure ofthe palm or base of the hand of the operatolgand the aint controlling iin er ly1n` era le-by te pull of lingers of such hand. 3. In combination` in a pneumatic air brush, -of a discharge head carrying air and paint nozzles, supply-,tubes leadin wardly fromlsaid head, a pair of simi ar side plates fitting over and enclosingsaid tubes and including rear extension portions and one or morev of t e grip., portions, opposing .semi-cylindrical forward of t e grip, and o Athreaded parts at the ends of said ortions fitting around said supply tubes, c amping nuts on said threaded arts for securing the tubes and side plates 1n assembled relation, valves for controlling the flow `through the tubes, and trigger means for operating the valves. y y

4. In combination -in a pneumatic -air brush, of a discharge head carrying air and paint nozzles, supply tubes leading rearwardly from said head, a pair of similar sidel plates fitting over and' enclosing said tubes and including rearY extension portionskand grip portions, opposing semi-cylindrical threaded parts at the ends of saidportions fitting Varound said supply tubes, clampingA nuts on said threaded parts for securing the y tubes and side plates in assembled relation,

valves for controlling the {iowthrough the tubes, anda pair of triggers for controlling the flow through said tubes mounted between the side plates, the said supply tubes being detachably secured to said head.

5. In combination, in a pneumatic air brush, of a discharge head carrying air and pait `nozzles, lan air supplyV tube leading rearwardl from said head, a'flexible aint supply tu e leading rearwardly and aterally from'said head' and detachably secured' thereto, a pair of similar'side plates fitting y over and enclosing said tubes; and including forward extension portions fitting around the forward' ends of the tubes," rear extension portions fitting -around the rear, end of the air tube, and grip Aportions extending laterally fitting around the iexible paint tube, opposing semi-cylindrical "threaded parts at the ends of the rear extensions and v flow through the tubes, for operating the valves.

grip extensions, clamping nuts on saidL threaded portions, valvesv for controlling -the 6. Inncombination. in a pneumatic air brush, of a` discharge head carrying air and paint'nozzles, an air su ply tube' leading'rearwardly from said cad, a'iiexible extension portions fttin and trigger means subscribed paint supply tube leading rearwardly and laterally' from said head and detachabl secured thereto, a pair of similar side p atesv fitting over `and enclosing said tubes, and

including forward extension portions fitting around'the forward ends of the tubes, rear end of the air tube, an grip portions extending laterally fitting around lthe flexible paint tube, opposing semi-cylindrical 'threaded parts at the ends of the rear extensions around the rear and grip extensions, vclamping nuts on said threaded portions, valves for controlling the fiow through the tubes, and trigger means for operating the va1ves,the said air ,and

supply tubes having threaded engagement with said head lat their forward ends.

7. In combination in. a` pneumatici; air

brush, an air nozzle, a supply tube leading brush, an air nozzle, a supply tube-leading thereto and having a slot through its side, an air admission valve at the rear end of the tube opening-bv 'a rearward movement and yieldingly held forward in closed position, a forwardly projecting stem on said valve, an operatingtube slidingly mounted in the supply tube and having aprojcction extending through the slot in fthe supply tube,

means' carried by the operating tube for fengaging the stein of the valve, and a trigger for moving said projection. y

In testimony whereof, I have4 hereunto my name this 5th day. of March,

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