US2661310A - Apparatus for and method of painting - Google Patents

Description

G. .1. PAGE ETAL 2,661,310 APPARATUS FOR AND METHOD OF' PAINTING Dec. 1, 1953 4 Sheets-Sheet l Filed June 25. 1949 1N ENTORS Georg? J a e am! Jo n /czr (son Y* Dec. 1, 1953 G. J. PAGE r-:T AL

APPARATUS FOR AND METHOD OF PAINTING 4 sneetsfsheet Filed June 25. 1949 INXENTORS. `ge J. crge and John Warrzsqn Gear lBY

Dec. l, 1953 G. J. PAGE ETAL 2,661,310

APPARATUS FOR AND METHOD OF' PAINTING Filed June 25. 1949 .4 sheets-sheet s N TORS @Hijs I V George a @and Dec. l, 1953 G. J. PAGE x-:TAL 2,661,310

APPARATUS PoR AND METHOD oP PAINTING Filed June 25, 1949` 4 Sheets-Sheet 4 NVENTORS. 6e e P a e and l LI Jozrgfnrrl n Patented Dec. 1, 1953 APPARATUS FOR AND METHOD OF AINTING George J. Page and John Harrison, Chicago, Ill., assignors to The Spra-Con Company, Chicago, Ill., a corporation of Illinois Application June 25, 1949, Serial No. 101,396

14 Claims.

This invention relates to apparatus for and method of painting, although, as will be pointed out hereafter, the apparatus may be employed in applying other fluids to articles. For the purpose of illustration, the use of the apparatus in applying paint will be described specifically for the purpose of rendering clear the character of the apparatus as well as the method.

In the application of paint industrially to manufactured products, the use of spray guns or spraying apparatus is common but the installations required for painting by the spraying method and by considerations of the health of those who carry on the operations not only are costly initially but the operations of such installations are expensive by reason of power consumption including the supplying and treatment of air in relatively huge quantities and also by reason of space requirements and the waste of paint materials. Furthermore, notwithstanding the use of approved washing and other apparatus calculated to prevent the escape of paint particles to the outside atmosphere, not infrequently property damage occurs at considerable distances from the spraying installations by reason of the deposit of paint particles from the atmosphere as upon parked automobiles, for example.

In an effort to overcome some of the disadvantages inherent in the paint spraying of articles industrially, the flowing or jetting of paint in liquid form, as distinguished from atomized paint as in spray painting, has been developed wherein numerous nozzles are arranged in various fixed positions along a paint chamber for jetting liquid paint upon the particles moving through the chamber. Such nozzles direct the liquid paint upon the articles to flood the surfaces thereon to be painted, the excess paint draining off and being returned to a tank for replenishment of solvent or thinner to adapt the paint for re-use. Such nozzles have been so spaced necessarily that the entire surface to be painted would be coated or flooded with paint and, for eliminating the possibility that some areas of the article would not receive paint, the nozzles have been arranged generally so that areas covered by the nozzles overlap areas of other nozzles. A relatively large quantity of paint is thus directed upon each such surface as compared with the amount actually required to coat the article for insuring that the surfaces to be painted will be fully covered by the paint. This method of painting, known to the trade frequently as flow coat-l ing is wasteful of paint solvents or thinners which escape from the surplus paint that is flooded on the articles in the painting chambers. A substantial portion of the excess or surplus paint drips from the articles into the drains for recovery of the paint pigments but, as will be seen, the aeration of the paint passing from the 2 nozzles to the articles and from the latter to the drains results in substantial loss of thinner and necessitates replenishment of the thinner in restoring the retrieved pigments to the proper viscosity for re-use.

In the flow coating method of painting, the paint is jetted from the nozzles at relatively low pressure as compared with the pressure used in the paint spraying method. Three to five pounds per square inch is usually employed in the flow coating method, such pressure being provided by a pump which effects circulation of the paint from a main supply tank through conduits to the nozzles which, as indicated above, direct the liquid paint in sheet or stream form upon the surface of the articles to be painted.

It is an object of the present invention to provide apparatus for and a method of applying liquid paint at relatively low pressure to articles moving through a paint chamber which will require the circulating or jetting of less paint to insure complete coverage ofthe articles as compared with the previously described prior method of flow coating and hence will result in proportionately lower solvent or thinner losses.

Another object of the invention is to provide an apparatus comprising a plurality of nozzles for flooding or flow coating articles, preferably movingr continuously through a coating chamber, at least some of the nozzles being movable in predetermined or selected paths for jetting liquid paint or other surface treating fluid upon the articles to thereby distribute the fluid over relatively greater areas of the articles as compared with stationary nozzles of the type abovementioned.

An additional object of the invention is to provide painting apparatus comprising a tunnel structure through which the articles to be painted are moved by a conveyor, preferably continuously, the tunnel, in some instances, providing a chamber or zone for preconditioning the articles as to temperature, a paint applying chamber, and a heating or drying chamber and in instances where two coats are to be applied to an article, the tunnel preferably is extended to provide for the application of and drying or setting of said second coat.

A further object of the invention is to provide apparatus for painting articles industrially moving through a tunnel structure which comprises not only means for preconditioning the paint as to temperature for reducing the formation of bubbles on or in the body of the applied paint but includes means also to facilitate the draining of excess paintfrom the articles for avoiding accumulation of thickened paint at the lower edges of the painted parts or surfaces.

Another object of the invention is to provide a tunnel structure through which articles are movable during the paint applying and drying operations and through which from the intake end thereof to an exhaust duct at the outlet end, a current of air is moved for scavenging the thinner vapors for avoiding the contamination of the atmosphere of the surrounding areas where an attendant or attendants supervise the operation of the painting apparatus.

By means of the present improvements when used for painting articles of a type suitable for such mode of paint application, not only is there a substantial saving in thinners or solvents over prior methods of industrial application of coating materials but the original installation and the operation thereof generally are less costly from the standpoint of power consumption, floor space, and labor requirements and, as compared with the spray coating method, health hazards to the workman and likelihood of property domage. to areas adjacent the installations have been eliminated or the conditions vastly improved.

Qther objects of the invention will be apparent from the consideration of the following specication and accompanying drawings wherein;

Figure 1 is a broken side elevation of a tunnel and associated structure of a character adapted for use in carrying out the improved method of applying paint or other coating compositions or surface treating fluids to articles industrially;

Fig. 2 is a broken top p lan view of the structure shown in Fig. 1;

Fig. 3 is an enlarged sectional view taken approximately on line 3-,3 of Fig. l;

Fig. .i is a broken top plane view of a portion of a tunnel showing a modified form of mechanism for moving the uid applying nozzles; Fig. 5

is a broken elevational view of the structure shown in Fig. Fig. 6 is a sectional view taken on line 6.-.,6 of Fig. 5; Fig. -7 is a broken plane view of a further modified nozzle operating mechanism; Fig. 8 is an elevational view of the structure shown in Fig. 7.

In Fig. 1 of the drawings, a tunnel structure is shown indicated generally by the numeral ID, this structure comprising a suitable supporting framework, not shown in detail, for supporting sheet metal walls which define the tunnel. EX- tending along the upper part ofthe tunnel, which is open at opposite ends, is a supporting track II for an endless conveyor I2, not shown in detail,

but being of any approved type capable of con- 7 veying to and through the tunnel the articles to be painted. Such articles are of numerous types, such as cabinets (wood .or metal), refrigerator casings, castings and numerous other articles.

The conveyor I2 preferably is of the endless type,

generally, a paint applying zone where the articles are coated, a heating zone in which the drainage of the surplus paint from the articles is augmented, and a drying zone. These zones are of such length that the articles receive appropriate treatment as they progress through the tunnel. In Fig. l of the drawing, a tempering zone A is indicated which is provided with means for assuring that the articles to be painted are at the proper temperature as Vthey enter the coating zone. Frequently, in industrial plants, articles of metal are degreased or washed prior to painting and after washing they pass through a drying tunnel. The present tunnel may re- ,ceive articles directly from the last mentioned drying tunnel and, in some instances, the articles may be at a proper temperature for painting in which instance the zone A of the tunnel I0 may be omitted. However, in Fig. 1 zone A of the tunnel is shown as being provided with temperature conditioning means which may be in the form of steam pipes indicated diagrammatically at IIEL for preheating the entering articles. In tunnel installations where the articles to be painted are or are likely to be at a temperature above that required for best painting results, the tunnel section n may be provided with means for reducing the temperature of the articles such as by the provision of cooling ducts (not shown) Within the section A, for example. The succeeding zone or section of the tunnel is indicated by the letter B and is the zone where the coating material, such as paint, is applied to the articles and in which the major portion of the surplus paint drains from the articles and is recovered for reuse. The next adjacent section is indicated by the letter .C and generally is the zone where the articles are subjected to a temperature controlled atmosphere. Where the applied liquid is paint, the atmosphere of zone C generally is heated for the purpose of causing the remaining surplus paint to drip more freely from the painted articles thereby eliminating the formation of bubbles or pin holes such as sometimes cause an orange peel appearance. In some instances the atmosphere of zone Q may be reduced to a predetermined degree where a cool or refrigerated atmosphere produces desired results by controlling fluidity or the action of the solvents employed. The paint that drips from the articles in zone or chamber C may be recovered periodically, but generally it is too viscous to drain back into the paint circulating system. The last zone, indicated by letter D, is a drying zone which is of adequate length whereby the articles passing therethrough will be adequately dried for re.- moval from the conveyor or for entrance to a second tunnel for receiving a second coat or if preferred for transfer again to the entrance end of the same tunnel for such lsubsequent coat.

For the purpose of avoiding contamination of the atmosphere ,snrrounding the tunne1 by the vapors of solvents or thinners or of the other coating or fluid constituents, means are provided for inducing a flow of air longitudinally through the tunnel in the direction of the movement of the articles, that is, from left to right as viewed in Fig. 1. In Fig. 1 such circulating means ,is shown as comprising a pair of vertical ducts I3 having air intake openings I 4, the ducts being mounted adjacent the inner side walls of the oven, A booster fan I5 operated by a motor I6l draws air into the ducts I3 through the inlet openings I4 and forces the same through a horizontai duct II at the top of the tunnel and thence downwardly through vertical ducts I8 whence the air passes throiigh outlet openings I9 in the direction of the travel of the articles. The two pairs of ducts I3 and I8 are located adjacent opposed side walls of the oven to provide adequate intermediate Sposo between the ducts 0f each. @oir for the passage of the articles through the orenf At the outlet ond of the oven there is provided a pair of vertical ducts 2I1'disposed along opposite side walls of the oven and having at their inwardly directed faces inlets 2|. The upper ends of the ducts communicate by a horizontal conduitl 22 with an exhaust duct 23. A fan 24 operable by a motor 25 draws air and evaporated thinner through the openings 2l whence they are exhausted through the duct 23 to the outside atmosphere. The above described air circulating and air exhaust means induces a flow of air into the inlet end of the tunnel which carries through the tunnel the vaporized thinner or solvent and discharges the air and thinner vapors through the exhaust 23 thereby avoiding the contamination of the ambient atmosphere.

Within the section or zone B, the coat-applying nozzles are located for applying the coating or fluid material, such as paint, to the articles as the same move from left to right within the section. The nozzles within section B that apply the major portion of the coating to the articles are made movable so that paint jetted from such nozzles will be applied over a larger portion of the surfaces of the articles than where such nozzles are stationary. Since fewer movable nozzles are required for adequately coating an article moving through the painting zone than where stationary nozzles are employed, less paint need be jetted through the nozzles and since less paint is subjected to theatmosphere within the tunnel (assuming a given pressure and nozzle capacity), less thinner loss occurs and generally a more economical paint-applying method is provided. Likewise, the movable nozzles give the respective jets of paint a greater tendency to spread out and flow upon the surface and to seek out surface formations which might escape being coated were the nozzles stationary.

The movement of the nozzles may be varied as to velocity whereby a given installation or arrangement of nozzles within the painting zone may be regulated for obtaining satisfactory results in the coating of articles of different forms or shapes or of surface characteristics. Likewise, the movable nozzles preferably are adjustable for varying the range of application of the coating material upon the articlesl particularly in instances where the nozzles are rotatable, as shown in Figs. 1, 2 and 3 of the drawings. In

Fig. 3, an article 26 is shown suspended by the carrier |2, the article represented being, for ex ample, a cabinet requiring painting on its exterior surface. For the purpose of illustration, three movable nozzles are provided, the nozzles being indicated by the numerals 21, 28 and 29. Each of the nozzles is shown as being rotatable about a given axis for jetting or sheeting liquid paint upon the article 26 as it moves through the paint-applying zone B. Nozzle 21 is shown as being supported by a radial arm 30 adjustably mounted on a rotatable shaft 3| journalled suitably in the side wall or frame structure of the tunnel and having an axial passage 32 extending from the outer end to a flexible duct 33 which carries the coating composition to the nozzle under a relatively low pressure supplied by means hereinafter disclosed. A pipe 34 supplies the liquid paint to the intake end of the shaft 3|. On the opposite side of the oven is located nozzle 28 carried by an arm 35 which is mounted for radial adjustment in a shaft 36 which may be journalled in the side wall or the frame of the oven. The shaft 36 is provided with a passage similar to that above described for supplying liquid paint to a flexible duct 31 that conveys the paint to the nozzle 28. Ihe paint is supplied to the passage in the shaft 36 by a duct 38. The

of the tunnel and is supported adjustably by a' rotatable shaft 40 having an axial passage therein through which paint may be suppliedto a flexible duct 4| which carries the paint to thek nozzle 29. A pipe 42 is shown for conveying paint from a source of supply to the shaft 40. The nozzle 29 is supported by a radially adjustable arm 43 which may be secured in an -adjustable position on the shaft 4U lby aset screw 43a, for example. The nozzles mentioned may be rotated by any appropriate means.

In the drawings, we have shown a motor 44v located on the top of the tunnel which effects rotation of a transverse shaft 45 by means of a variable drive mechanism 46, adjustment of which enables the shaft 45 to be rotated at selected speeds. The ends of the shaft 45 are shown provided With pinions 41 and 48 which by means of chains 49 and 59, respectively, drive sprockets 5| and 52 located on the shafts 32 and 36 for rotat ing the latter, as above described. The shaft 40 is shown provided with a beveled gear 53 driven by a beveled pinion 54 mounted on a shaft 55 carrying a sprocket 55 which is driven by a chain 51 which, in turn, is operated by a sprocket 58 The nozzles 21 and 28l mounted on a shaft 32. will, as they rotate, eject liquid paint over the entire side surfaces of the article 26 as the same moves through the painting zone. The nozzle 29.

- article as such end comes within the paint disbursing range of such nozzles. For the purpose of applying paint to the upper surface of the nozzle, in the particular installation shown in the drawings, we have shown a pair of stationary nozzles 59 and E3 which are arranged to spray paint over the the adjacent surface of the articles as it moves through the painting zone. As shown in Fig. 1, the nozzles 59 and 6D are located to the right of the path of rotation of the movable nozzles 21 and 23. We have found that application of excess paint by nozzles 59 and 60 produces a secondary flooding of the side surfaces that facilitates drainage of the paint from the surfaces previously acted on by the nozzles 21 and 28.

In any given installation, the nozzles are so located as to insure the application of paint to the entire surfaces of the articles to be painted.V

Such surface may be interior surfaces in many instances where openings are available for the entrance of paint from the nozzles as Well as for.

drainage of excess paint from such surfaces. It

will be seen that the adjustment of the rotatable y' nozzles adapts the particular apparatus shown to the coating or the painting of articles of different sizes. In industrial painting, a given installation generally is used for painting articles of like form,

dripping of surplus paint therefrom. Likewise the heat in the chamber reduces the viscosity of the paint and promotes the formation of a smooth uniform coat of paint on the articles without leaving'pin holes or an orange skin eifect resulting from the formation of bubbles as the thinner evaporates from the coat.

The means above referred to for supplying a saturated thinner vapor to the atmosphere in chamber C is for illustrative purposes only since other modes of supplying the vapor may be utilized, as for example, generating solvent vapor by the application of heat to an appropriate thinner containing receptacle and conducting the generated vapor into the chamber.

Where, as shown in Figs. 1 to 3 inclusive, the nozzles move in rotary paths during the applicationV of paint or the like to articles moving through the coating chamber, the nozzles tend to apply the paint in annular bands of a width depending on the adjustment or paint spreading character of the nozzles and the distance from the surfaces being coated. Since the articles move rectilinearly during the application of .the paint, the bands are not truly7 circular but are elongated in the direction of movement of the articles, the rate of rotation of the nozzles being such as to cause each band to overlap, slightly at least, the preceding band to eifect complete coverage of the respective surface of the article as it moves into and through the range of the nozzles.

Asthe articles move from left to right in the structure shown in Fig. 1, the nozzles 27 and 28 preferably rotate in a clockwise direction as viewed from the left in Fig. 3, that is, the nozzles move from left to right in the upper portions of their orbital paths. Since the nozzles in the upper portions of their orbits move kgenerally in the same direction as the articles being painted,

the velocity of the nozzles in the upper arcs, relative to the rate of movement of the articles, is less than in the lower portions of the orbits Where they move generally in a counterdirection with respect to the movement of the articles and hence more paint per unit area will be applied to the articles at the upper portions of the nozzle orbits than in the lower portions. Such application of paint in greater volume per unit area to the upper portions of the surfaces being painted provides adequate paint for flowing down over the surfaces to provide a uniform coating while the reduction of the volume of paint applied per unit area to the lower portions of the surfaces reduces the excess that must be drained off gravitationally with the aid of heat in chamber C or by the supplemental aid of a thinner-enriched atmosphere provided by atomization of thinner by the nozzles 88 or by other appropriate means.

In the improved method and apparatus, rotary nozzles, similar to nozzles 27 and 28, are preferred in applying coating to vertical or steeply inclined surfaces such as the side and end walls of the cabinet shownA in Fig. 3. While nozzle 29 also is shown as being rotary, a stationary nozzle or nozzles may be employed for coating the lowermost surfaces of the articles or, in some instances, an oscillating or reciprocating nozzle may be employed in lieu of a rotary nozzle, particularly for applying coating to a lateral or lower surface of an article, as described hereinafter. However, the movable nozzles are of advantage as pointed out above since they distribute the paint over a greater area in a given time unit than do stationary nozzles (other things being equal) while the centrifugal action produced by the rotary nozzles projects paint streams in trajectories that, entering openings in cabinet walls, will strike on and iiow over interior surfaces not accessible by streams projected by stationary nozzles. Hence'painting interior Walls, as well as exterior walls, of some articles is possible with the present improvements, as will be seen.

In Figs. 4 and 5 mechanism is shown for oscillating certain of the nozzles of the apparatus, such as the lateral nozzles 93. Such oscillating nozzles may be used in lieu of rotary nozzles 21 and 2S, particularly in some instances where the centrifugal eiect provided by the rotary nozzles is not important. An oscillating nozzle or nozzles may be provided in lieu of the rotary nozzle 29 of Fig. 3 if desired. Thus in the structure shown in Figs. 4 and 5 eachof the nozzles 93 is mounted on an arm 94 in communication with an axial passage 95 that supplies paint or other liquid to the nozzles by means of a exible duct 95 from a source of the iluid under pressure, such as a pump previously described. The arm 34 is carried by a rocking bar 91 pivotally mounted at Sie to a portion of the tunnel frame. A connecting rod 98 is attached to the bar and to a crank arm S3, carried on one end of the rotary shaft iii@ journalled at the top of the tunnel and which is operated by a motor lill through suitable variable drive mechanism. As a nozzle 93 is oscillated in use it jets the liquid upon successive articles moving through the tunnel as above I described, the rate of oscillation with respect to the movement of the articles from left to right being such as to effect application of the iluid in over-lapping paths to insure coverage of the surface portions of the article acted on by the nozzle. As shown in Fig. 4 the chamber B is provided with ofl-set portions H22 in or adjacent which the nozzles move, suitable passages in the forward wall of each off-set portion being provided with an elongated aperture for accommodating the respective arm 94.

In Figs. i and 5 the upper nozzles shown in Fig. 3 are omitted for the sake of simplicity as 'are the temperature conditioning means, `air circulating means and other features of the tunnel apparatus above described.

Where oscillating nozzles are employed at the sides of the tunnel as shown in Figs. 4 and 5, means for reciprocating a lower nozzle or nozzles may be employed if desired or a reciprocating nozzle may be employed in the structure shown in Fig. 3 in lieu of the lower rotary nozzle 29. In Fig. 6 an oscillatable member lil?, is shown carrying a tubular arm IM provided with two nozzles |95 each communicating with an axial duct 06 to which paint or other liquid is supplied by a flexible tube Il'l from a pressure source. The member ID3 can be operated by any suitable means to move the nozzles transversely of the path of travel of the articles to jet paint upon the lower surfaces of the articles. The member 103 is shown as being' operable by a link |08 connected to a bell crank'lever |09 which in turn is operated by a rod il@ pivotally connected to the adjacent bar 91.

The movable nozzles at the side of the tunnel may be reciprocated by suitable mechanism if desired rather than oscillated as shown in Figs. 4 and 5 or rotated as shown in Figs. l to 3 where all the advantagesof the rotatable nozzles is not required due to the character of the work to be 11 done. In Figs. 7 and 8 chains III are shown mounted on upper and lower sprockets I I2, H3 at each side of the tunnel, the sprockets beine mounted on upper and lower horizontal rotatable stub shafts IIil and IIS, respectively, that may be suitably supported by the frame of the tunnel- A nozzle II5 is swiveled to each chain, as to an extended link pin thereof and is supplied with paint or other fluid by a flexible tube IIT to which, from a source such as has been referred to above, receives the fluid from a pipe I I8. The chains ill are operated by a chain i9 operating sprockets H2 secured to. the upper stub shafts H4 and driven from a rotatable shaft |20 that is operable by a motor 2| through a variable speed drive mechanism.

The nozzles I I El, in the structure shown, follow the path of the chains il! and apply the paint or other liquid being used, in paths that are vertical generally.

'lhe apparatus shown has been described particularly with respect to the applica of paint or coating materials to articles industrially- However, it win oe seen that apparatus of. the character shown may be used for other purposes requiring the use of other surface treating fluids- For example, water or other Washing fluid may be ietted upon articles by the improved apparatus for cleansing or stripping purposesy or paint remover o r the like may be used for removing T paint or other coating rnaterials from articles moving through the tunnel or even etching fluid may be ietted from appropriate nozzles foi' etching the surfaces of articles or unmasked portions thereof- While various controls may be employed for controlling or regulating temperatures of the several zones of the tunnel, particularly in zones C and D, these have not been shown but it will be clear from the foregoing description that the temperature of the paint or other coating or fluid applied to the articles, as Well as the temperature of the articles themselves, may alfect. the quality of the final results, It will alst) be obvious that in some installations, depending on the i,

size, shape and other characteristics of the article being treated, the relative location of the several nozzles may be varied ,from that shown and that other changes may be made all within the spirit of the invention defined by the following claims.

We claim:

l. In the method of treating the surfaces of an article with a liquid composition comprising the steps of mounting the article in position whereby it is relatively free of pockets which might prevent drainage of excess liquid from the surfaces thereof, advancing the mounted article rectilinearly, rotating a liquid effusor about a crcular path having an axis substantially perpendicular to the direction of movement of the article and offset from the path thereof but facing towards the article during movement, feeding the liquid composition in a continuous solid stream under pressure to the effusor whereby the liquid composition is ejected as a solid stream and is thrown solely by the combination of said pressure and centrifugal force onto the surfaces of the article as it passes by, and balancing the rate of movement of the article and the volume of liquid thrown from the effusor to deposit liquid composition onto the surfaces of the article in amount suilicient to cause drainage from the surface.

2. In the method of painting surfaces of ar.- ticles by a flow coat process, the steps of mountlll ing the article a position to eliminate pockets which might prevent drainage of excessV liquid paint from the surfaces thereof, ativan` .g 'the mounted article rectilinearly through a rotating an effuscr about a circular path having an axis Substantially perpendicular to the direction of movement of the. article through the .housing and offset from the path thereof but directed toward the article as it passes therethrough. feeding liquid paint composition in a continuous .solid stream under pressure to the elusor. Whereby the liquid paint composition is ejected as a solid .stream and is thrown solely by the com.- binaticn of said pressure and centrifugal force onto the, surfaces of the article as it passes through the housing, and balancing the rate of movement of the article through the housing with the volume of liquid paint thrown from the effuscr to nood the surfaces of the article with the paint composition- 3t ,In the method of painting surfaces of ar,- ticles by a new coat process, the steps or monate ing the article a position to eliminate pockets which might prevent drainage of excess licuid paint from the surfaces thereof, advancing the mounted article rectilinearly through a hating, rotating an eifusor about a'circular path having an axis substantially perpendicular tothe 'direction of movement of the article through the housing and offset from the path thereof but directed toward the article as' it passes therethrough, feeding liquid paint composition va continuous solid stream under pressure tothe emisor whereby the liquid paint composition is ejected as a solid stream and is tnrow's'soieittf the combination oi said pressure anducentriflugal force onto the surfaces of thearticle-asmlt passes through the housing, balancing th'rate of movement of the article through 'the housing with the volume of liquid paint thrown from the effusor to flood the surfaces of the 'articlenwith the paint composition, and maintaining the tem'.- peralture of the paint composition at a constant eve u 4. 1n the method of painting surfaces of ar.- .ticles by ay flow coat process, the steps of mount? lng. the article in a position to eliminate pockets which might prevent drainage of excess liquid paint from the surfaces thereof, advancing the mounted article rectilinearly through a-housing. rotating an effusor about a circular path having an axis substantially perpendicular to the direc: tion of movement of the article through the house ing and offset from the path thereof but directed toward the article as it passes therethrough, feede ing liquid paint composition in a continuous solid stream under pressure to .the .effusor whereby the liquid paint composition is ejected as a solid stream and is thrown solely bythe combination of said pressure and centrifugal force .onto the surfaces of the article as it passes through trie housing, balancing the rate of movement of the article through the housing with the volume of liquid paint thrown from the effusor to oodthe surfaces of the article with the paint composition, and maintaining an atmosphere of solvent-vapors 1n a drainage area immediately following' the area of paint application whereby the vexcess paint composition is more completely removed from the surfaces. i* I' 5- .In the method of painting surfaces of articles by a flow coat process, the steps of lmount-l ing the article in a position to eliminate pockets which might prevent drainage ofoxcess ironia paint from the surfaces thereof, v'ac lva'ricing the

Claims (1)

1. 4. IN THE METHOD OF PAINTING SURFACES OF ARTICLES BY A FLOW COAT PROCESS, THE STEPS OF MOUNTING THE ARTICLE IN A POSITION TO ELIMINATE POCKETS WHICH MIGHT PREVENT DRAINAGE OF EXCESS LIQUID PAINT FROM THE SURFACES THEREOF, ADVANCING THE MOUNTED ARTICLE RECTILINEARLY THROUGH A HOUSING, ROTATING AN EFFUSOR ABOUT A CIRCULAR PATH HAVING AN AXIS SUBSTANTIALLY PERPENDICULAR TO THE DIRECTION OF MOVEMENT OF THE ARTICLE THROUGH THE HOUSING AND OFFSET FROM THE PATH THEREOF BUT DIRECTED TOWARD THE ARTICLE AS IT PASSES THERETHROUGH, FEEDING LIQUID PAINT COMPOSITION IN A CONTINUOUS SOLID STREAM UNDER PRESSURE TO THE EFFUSOR WHEREBY THE LIQUID PAINT COMPOSITION IS EJECTED AS A SOLID STREAM AND IS THROWN SOLELY BY THE COMBINATION OF SAID PRESSURE AND CENTRIFUGAL FORCE ONTO THE SURFACES OF THE ARTICLE AS IT PASSES THROUGH THE HOUSING, BALANCING THE RATE OF MOVEMENT OF THE ARTICLE THROUGH THE HOUSING WITH THE VOLUME OF LIQUID PAINT THROWN FROM THE EFFUSOR TO FLOOD THE SURFACES OF THE ARTICLE WITH THE PAINT COMPOSITION, AND MAINTAINING AN ATMOSPHERE OF SOLVENT VAPORS IN A DRAINAGE AREA IMMEDIATELY FOLLOWING THE AREA OF PAINT APPLICATION WHEREBY THE EXCESS PAINT COMPOSITION IS MORE COMPLETELY REMOVED FROM THE SURFACES.

Images