US2874677A

US2874677A - Method and apparatus for liquid application

Info

Publication number: US2874677A
Application number: US617067A
Authority: US
Inventors: Alfred E Braun; Thomas C English
Original assignee: WOOSTER SEALKOTE Co
Current assignee: WOOSTER SEALKOTE Co
Priority date: 1956-10-19
Filing date: 1956-10-19
Publication date: 1959-02-24
Anticipated expiration: 1976-02-24

Description

METHOD AND APPARATUS FOR LIQUID APPLICATION Filed Oct. 19 1956 Feb. 24, 1959 A. E. BRAUN ET AL 4 Sheets-Sheet 1 'INVENTOR. ALFRED E. BRAUN NGLISH BY THOMAS C E ATTORNEYS Feb. 24, 195 9 A. E. BRAUN ET AL METHOD AND APPARATUS FOR LIQUID APPLICATION 4 Sheets-Sheet 2 Filed Oct. 19, 1956 INVENTOR. ALFRED E. BRAUN BY THOMAS C. ENGLISH WWW/M 9 f f is llllllfNllllLllll ATTORNEYS A. E. RAuN ET AL Feb.24, 1959 METHOIQV AND APPARATUS FOR LIQUID APPLICATION 4Sheets-Sheef 3 Filed Oct. 19; 1956 INVENTOR. ALFRED E. BRAUN BY THOMAS C. ENPL/SH PWMMI gwfivf ATTORNEYS 1959 A. E. BRAUN ET AL 2,874,677

METHOD AND APPARATUS FOR LIQUID APPLICATION Filed 001?. 19, 19 56 4 Sheets-Sheet 4 IN V EN TOR.

ALFRED E. BRAUN THOMAS C; ENGLISH ATTORNEYS :METHOD AND APPARATUS FOR LIQUID 1 APPLICATION Alfred E. Braun and Thomas (1. English, Wooster, Ohio,

assignors to The Wooster Sealkote Company, Wooster, Ohio, a corporation of Ohio I Application October 19, 1956, Serial No. 617,067

14 Claims. (Cl. 118-305) under these spray heads. In the present invention a plurality of spray heads are mounted on a movable frame which passes along a large, unconfined surface of substantially constant cross section with the spray heads held in appropriate spaced relationship by a tracking ipacing mechanism to either cleanse or paint such surace.

It is, therefore, one of the principal objects of this invention toprovide both a method and an apparatus for mass preparation and painting of large, unconfined surfaces of substantially constant cross section.

A further object of this invention is to provide an apparatus having means to hold a plurality of spray heads in appropriate spaced relationship with a surface to be treated and means to move the spray heads along such surface.

Another object of this invention is to provide a mobile liquid applicating device which may be moved along a path which is substantially rectilinear and which generally parallels a surface to be treated, which mechanism follows such surface having a spacingor tracking device for gauging the distance between a spray head and a surface being treated. i

An additional object of this invention is to provide a mobile frame member which carries a plurality of spray heads and at least one spacing wheel to hold such spray heads in constant spaced relationship with a surface to :be treated.

Yet another object of this invention is to provide a device constructed in accordance with the foregoing obfjects and to provide in addition counterweights to hold to fit the contour of any surface which it is desired to treat.

Still another more special object of this invention is to provide an adjustable spacer to permit the frame and the spray heads to be placed at a selected angle with a surface to be treated.

Still another and more detailed object of this invention is to provide a motor propelled device made in accordance with the foregoing objectives which may be moved horizontally along a long surface, such as the surface of a tunnel, to apply a liquid to such surface.

Still another more special .object of this-invention is to provide a gravity propelled device which may be moved along a substantially vertical surface, such as the outer surface, of, a silo, for application of liquid to such surface.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims, vtaken in conjunction with the accompanying drawings, in which:

Figure 1 is a fragmentary perspective view of a truck drawn embodiment ofthe mass painting device of the invention;

Figure 2 is a fragmentary sectional View of a tunnel with the deviceof Figure 1 in a slightly modified form shown in an end view as it is being drawn through the tunnel;

Figure 3 is a fragmentary side elevational view of the device as it is being drawn through the tunnel of Figure 2;

Figure 4 is a schematic diagram of a spray head and the mechanisms for providing fluid to the spray head and for controlling the spray head;

Figure 5 is a side-elevational view of a spray head and an improved spray head mounting member;

Figure 6 is a rather schematic side elevational view of a silo and of a gravity operated device for treating the silo surface;

Figure 7 is a top plan view of the device of Figure 6; V

Figure 8 is a fragmentary sectional view of the gravity operated device of Figure 6;

Figure 9 is a somewhat schematic fragmentary top lar, the entrance to a tunnel 10 is shown schematically.

.the spacing wheels in constant contact with the surface to be treated.

Still another object of this invention is to provide a mobile device having a plurality of liquid spray heads :and a plurality of pressure control valves to provide equalized pressure in each of the spray heads and if de- :sired higher pressure in one or more of the spray heads.

Another object of this invention is to provide a mobile device having a plurality of spray heads and a single control member for starting and stopping the flow of liquid through the spray heads.

Another and more special object of this invention is 7 :to provide a mobile frame member having a plurality of spray heads adjustably carried on the frame, thespray heads being adjustable over an area of generally' annular contour.

Another more special object of this invention is to provide an adjustable mobile frame member having a plurality of spray heads which member may be adjusted ill A truck in the form ,of a trailer 11 which is drawn by a tractor 12 is Provided. A compressor unit shown generally at 13 is connected to the trailer 11 and drawn with the trailer by the tractor 12. device is shown generally at 20. The liquid applicating device 20 is mounted on the trailer for movement with the tractor, trailer, and compressor.

In the specific embodiments of Figures 1 through 3, one operational form of the device is shown. This specific construction is designed primarily. for painting highway tunnels. The device of Figure 1 will disperse approximately six gallons of liquid per minute. If it. is desired to paint a tunnel approximately one mile long with first a thin mist coat, and then a second or covering{ coat of paint, it may be done with extreme rapidity and minimum trafiic obstruction. The device will paint one-half a tunnel at a time. Dispersing six gallons of paint per minute, the first or mist coat can be completed in approximately forty-five minutes in a mile long tunnel, the paint being applied at the rate of approximately four- A liquid applicating hundred forty square feet per minute. The second or covering coat requires about one hour and twenty-five minutes with the paint being applied at the rate of about two-hundred twenty square feet per minute.

In Figure l a pair of

vertical supports

21, 22 are provided. A frame composed of three sections 23, 24, is also provided. The

frame sections

23, 24, 25 are pivotally carried by the

supports

21, 22. The frame of Figures 2 and 3 is somewhat modified. The center frame section 24 is eliminated. End extensions are provided on

end frame sections

23, 25 to cover the same three surfaced area. It is thus apparent that where conditions warrant it, a custom made frame may be constructed for a specific job. Generally speaking, however, the adjustable segmented frame such as that shown best in Figure 9 and subsequently described in more detail, is preferred.

A plurality of spray heads are mounted on the frame. The operation of these spray heads 30 can best be understood by reference to Figures 1 and 4 in conjunction with the following description.

A reservoir 31 is provided. A liquid supply pump 32 is preferably mounted on the reservoir. In its preferred form, the pump 32 is air operated. The pump draws liquid from the bottom of the reservoir 31. An air supply tank 41 is connected to the pump through flexible conduit 33. In the device of Figure 1 the air supply tank 41 forms a part of the compressor unit 13.

The pump air supply line 33 has a pressure control valve 34 in it. The pressure control valve 34 is preferably an adjustable pressure control valve. The adjustable control valve 34 is placed at a setting which will provide the desiredair pressure to operate the pump 32.

A flexible liquid supply line 35 is connected to the pump. In the embodiment of Figure l the flexible line 35 is in turn connected to a rigid line 36 which forms a part of the frame structure. Branch fluid supply lines 37 are connected to the supply line 36. An adjustable pressure control valve 38 is provided in each of the branch lines 37. Through this construction a high fluid pressure can be maintained inthe supply line 36 to assure adequate volume to supply a plurality of spray heads 30 while the pressure reducing valves 38 reduce the pressure to constant and lower operating values for each of the spray heads 30.

A return fluid line 39 is provided. The return line 39 is connected to the top of the reservoir 31. Liquid in the reservoir is constantly agitated when the device is in operation by drawing it from the bottom of the reservoir and returning it to the top.

A pressure control valve 40 is included in the return line. The return line valve 40 serves to prevent excess pressure in the fluid supply lines and also serves to control the operation of the pump 32. If pressure in the desired operating range is present in the

fluid supply lines

35, 36, 39 the pump will not operate to force additional fluid into these supply lines.

An air control line is connected to the air supply tank. A control valve 46 (not shown in Figure l) is connected to the control line 45. The control line 45 is connected to the frame control line 47. The frame control line 47 is in turn connected to each of the spray heads 30 through branch control lines 48. Opening the valve 46 will substantially simultaneously open all the spray heads 30, and, conversely, closing the valve 46 will substantially simultaneously close all the spray heads 30. Thus, the spray heads may be simultaneously turned on and off. 7

An atomizing air line 50 is provided. The atomizing line 50 is connected to the frame atomizing line 51. A branch atomizing line 52 is connected to each of the spray heads 30 and to the frame atomizing line 51. An adjustable pressure control valve 53 is provided in each branch line 52. The purpose of the pressure control valves 53 is to' provide equal atomizing pressure to each of the spray heads while permitting excess atomizing pressure 4 to be maintained in the line 51 thereby assuring adequate atomizing pressure at all spray heads 30.

In operation, air under pressure is first introduced into the air supply tank 41. This air is conveyed through the conduit 33 and the valve 34 to the pump 32. The pump is then placed in operation and liquid under pressure is supplied to the

liquid supply conduits

35, 36, 39 until the pressure reaches the preselected maximum which causes the valve 40 to operate; At the same time atomizing air enters the atomizing lines 50, 51. A shutoff valve may, of course, be provided in the atomizing lines. After the atomizing and liquid pressures have reached their operational levels, the valve 46' may be turned on which in turn will'cause each of the spray heads 30 to be turned on and a spray operation may commence.

Referring again'to Figure l, the

frame sections

23, 24, 25 are pivotally carried on the

supports

21, 22. Springs 55 are provided to urge the spray heads toward a surface to be painted. In the embodiment of Figures 2 and 3, counterweights are employed to urge the spray heads toward the surface to be painted. The frame section 23 is urged by counterweights 56. The frame section 25 is urged by a counterweight 57 which is supported by line 58. The line 58 is reeved through block 59 to alter the vertical vector of the counterweight 57 to a horizontal vector.

A plurality of spacing wheels 60 are provided. As the spray heads 30 are urged by the action of the springs 55 or the

counterweights

56, 57 toward the surface to be painted, the spacing wheels 60 are urged into contact with the surface to be treated. Thus, as the device is moved along a surface of substantially constant cross section, the counterweights or springs will urge the spray heads toward the surface and the spacing wheels 60 will hold the spray heads away from the surface in substantially constant spaced relationship. It will be apparent that the cross section of the surface to be painted need not be precisely constant. The wheels 60 as provided in Figures 1 through 3 are of substantial diameter to ride over such surface imperfections as cracks and pits. Such surfaces as lapped or shingled houses could also be painted by this device. Thus, the limitation on irregularity is primarily controlled by the diameter of the spacing wheels 60. So long as the irregularities of the surface can be ridden over'by the wheels, the surface is sufficiently smooth to be treated by this device.

In Figures 1 through 3 there is disclosed an improved liquid applicating device for treatment of surfaces which are substantially parallel to the earths surface, or horizontal. That is, the liquid applicating device has a path of movement which parallels the earths surface. In Figures 6 through 11 rather schematic drawings are presented to show the operation of applicants device in painting a vertical surface such as a silo where gravity may be utilized as the motivating power. Additionally, several other features which may be included in applicants device whether it be operated in horizontal or vertical directions, are shown. For clarity of illustration, the details of the fluid conduction lines and valves have not been included in Figures 6 through 11. The circuit shown diagrammatically in Figure 4 is preferably used in these embodiments as Well as the embodiments of Figures 1 through 3.

Referring to Figures 6 through 8, overhead supporting booms'65 are provided. Silos and similar buildings are generally constructed with studs at the top of the side walls. These studs are normally used to anchor the roof. One successful method of anchoring the booms 65 is by anchoring them to these Studs which do not appear in the drawings.

Supporting

cables

66, 67 are provided. In this shown schematic support structure, the supporting cable 66 is reeved through

pulleys

68, 69 and the supporting cable 67 is reeved through the pulley 68 and pulley 70. The cable 66 is connected to the spray device 20' at suspension' point 71 (Figure 6) and the cable 67 is connected at suspension point 72 (Figure 8). A- suitable mech-* anism for drawing the

cables

66, 67 in and lettingthem out is provided. In Figures 6 and 7 this mechanism takes the form of hand winch 73.

' When a surfaceof curved cross section is to be treated, a curved frame member 75 is provided. This may best be seen by reference to Figure 7. In its preferred form the frame member 75 is segmental to permit adjustment of the frame so that it may conform in shape to any surface which is to be painted. The segmental construction is shown in Figure 9 which will be subsequently described in detail. For simplicity and "clarity of illusQ tration, the framesection 75 in Figures 6 through 8 is shown as a solid member. The frame member 75 may,

of course, be constructed as a solid member if it is commercially feasible to do so, as for example when a series of silos of the same diameter are to be painted.

Spacing wheels 76, which conform in function to the spacing wheels 60, are carried "on adjustable arms 77.

As can best be seen in Figure 8the spacing wheels 76 may bev spiked to provide good surface adhesion,

The suspension connections 71', 72 are preferablyso located that the

cables

66, 67 are parallel to or} tend to taper outwardly from the surface to be treated,fwhich surface is indicated as 78 in Figures.6, 7, 8 and 9. The" spray device 20 is so constructed that the center "'of gravity, when the device is in operation, is outwardof the suspension points 71, 72. In other words, the suspension points 71, 72 are between the center of gravity andthe spray heads 30, the wheels 76 and thesurface 78. counterweights 79 may be provided to assure the proper location of the center of gravity.

Since the

cables

66, 67 taper outwardly slightly from the surface 78, the entire mechanism tends to swing in toward the surface 78. With the center of gravity outward of the suspension points 71, 72 the device also tends to pivot about these suspension points so that the spray heads 30 and the wheels 76 tend to move upwardly while the counterweights 79 tend to pivot downwardly. Thecombi'nation of forces tending to move the device towardthe surface 78 and forces tending to pivot the device about the suspension points 71, 72 urges the spacing wheels 76 into firm contact. with the surface 78.

The wheelsupporting arms 77 maybe adjusted to control the extent to. which the entire mechanism pivots about the suspension points 71, .72. Varying the length of the supporting arms 77 to control the extent of pivoting also controls the desired spaced relationship of the spray heads 30 and the'surface 78. As will be more apparent when Figure 10 is described, spray head supports 81 may also be adjustable to aid in obtaining the appropriate spaced relationship b'etween the spray heads 30 and the -sur-. face 78. i r

As can best be'seen in Figures 6 and 7 the reservoir 31 and the air supply tank 41 are preferably located above a vertical surface which is tobe painted. With the reservoir 31 and the air supplytank 41 so located, the weight of the

fluid supply lines

35, 45, 50 isnot supported by the spraydevice 20' and in turn the cables vided. These sections are relatively pivotal about clamp able pivots 87. Thus, the frame may be adjusted to conform to the contour of any surface whether it be round, such as the surface 78 of Figures 6 through 9, or stepped, such as surface 88 of Figure 10.

In the device described in Figures 6 through 9, any number of sections such as

frame sections

83, 84, 85, 86 may be employed to permit, for example, a round surface to be painted without undue overlapping when a final portion of the round surface is painted. For example, when a silo is painted, the device may be assembled into an are which is about one-third the circumference of the siloand the entire silo is painted by setting thedevice up three times.

In Figures 10 and 11 a device which will paint from the ground to the very top of the surface 88 is provided. A frame section is provided in Figure 10 which is rigid. It, of course, may be telescopically adjustable to achieve the advantage just described with respect to the embodiment of Figures 6 through 9. In the device of Figures" 10 and 11 the wheels 76 are attached directly to the frame 95. The axes of the wheels are thus located in a plane common to the axes of the spray heads 30 and the spray head support arms 81.

Threecable suspensions

96, 97, 98 are utilized to give the frame 95 horizontal stability. Figures 10 and 11 show the extreme flexibility which can beachieved with this invention. A

spray device can be constructed to mechanically paint extensive surfaces where unusual and oddly shaped contours are present. This improved device has exceptional advantages both in affording immense labor savings over prior devices and techniques and providing great material savings. uniformity than with any prior known method.

As will be apparent from a study of Figure 10, the spray heads 30 are adjustably carried by the spray head support arms 81. This adjustmentmay best be seen by reference toFiguresS and 12. One of the outstanding features of the invention resides in the novel nozzle support. A nozzle support arm is adjustablycarried by a channel 106. The channel 106 may be a portion ofthe spray head support arms 81. Y

The adjustment support arm 105 is pivotal with respect to the channel 106. The adjustment support arm 105 has a pivot section 107 which passes through apertures 108, 109 in the channel 106. The adjustment sup port arm 105 is pivoted about the axis, of the pivot section 107 to its' desired position and then nuts 110 tightened down to lock the adjustment arm in the selected position.

The adjustment arm also has a gun support and section 112 which has an axis which is preferably normal to the axis of the pivot section 107. The gun 30 has a gun support bracket 113. The gun support bracket has an aperture 114. The gun support end section 112 may be inserted into the aperture 114. Preferably the gun sup- 66, 67. Further, when painting a tall structure fluid pres sure loss may become excessive if the reservoir and air supply tank are located on the ground rather than above the surface.

Inthe embodiment of .Figures 6 through 8 it will be noted that the'spacing wheels 76 are below the spray heads 30. This permits an operator to elevate the spray device 20'runtil the sprayheads"30 are at the top of or above the top of the surface 78. He may thus start painting at the very top andpaint the entire surface until he has almost reached the ground. 'Any touching up may then" readily be performed by an operator stationed on the ground with a hand spray gun;

In Figure .9 a frame section 75 is shown in enlarged port end section 112 and the aperture 114 are snugly fit. The gun 30 is pivotal about the axis of the gun support and section 112. A set screw 115 is provided to clamp the gun 30 in a'selected position.

It will thus be apparent that the gun 30 may be trained in an'infinite number of directions. contoured by the sum total'of all the possible locations of the gun 30 is an annulus which is somewhat donut shaped.

The gun adjustment described in conjunction with Figures 5 and 12, coupled with the variance in gun angle which may be obtained by adjusting the wheel support arm 77 of Figures 6 through 8, is provided for several reasons. One of the principal reasons is to permit painting a surface of any cross sectional configuration. Additionally, in some applications, it is desirable to direct the Nspray gun 30 either slightly upwardlyor slightly down- Further material is applied with far greater The geometric figure I tunnel which curves.

7 wardly. An example of such an application is a house with lapped siding or shingles where it is desired to paint a bottom surface which is substantially normal to be the major exposed surface of the siding.

A mechanism made in accordance with the present invention follows a rather straight path which is substantially rectilinear. The path may curve somewhat as for example in painting the surface of an auto or railroad Nonetheless the apparatus follows a path which generally parallels the surface to be painted. One of the exceptional features of the invention resides in the construction which permits this path to only generally rather than precisely parallel the surface being treated. This is achieved by providing spacers and means to urge the spacers into relatively constant contact with such surface. The spacers then track along such surface and serve to constantly gauge the distance between the spray heads and the surface.

' Prior to this invention, large, unconfined surfaces such as this could most rapidly be painted by a man manually carrying a single, or at most two, spray heads. Even the most skilled operator cannot maintain constant spacing between the spray head and the surface being painted. Further. such an operator will almost always overlap the paint applied during each of his passes by an excessive amount. Thus the present device will apply uniformly and efficiently giving a perfect covering with a minimum amount of paint.

Another exceptional feature of the present invention is the improved method of application of liquid to a surface. The liquid applicating device so disclosed is suitable for either cleansing or painting surfaces. An im proved and novel method for cleansing or preparing and/ or painting large, unconfined surfaces of substantial cross section has been devised which is both low-cost and high speed. The method is also superior to prior known techniques since extreme uniformity of application is obtained.

In preparing and painting such a surface the reservoir 31 is first filled with a cleansing solution such as a liquid detergent solution. The spray device is then moved across the surface to be painted and the detergent is sprayed along the entire surface; Plain water then may be placed in the reservoir 31 and a second pass is made across the surface. A liberal application of plain water rinses all the detergent and loosened dirt from the surface. A quantity of paint is then placed in the reservoir 31. If a water base paint, such as a Water base vinyl paint manufactured by the Wooster Sealkote'Co. and sold under the trademark Seal-Kote is employed, the surface may be painted before ithas dried. Then a third pass may be made across the surface to be treated immediately after it has been washed and rinsed. This third pass may apply a mist coat of paint such as has previously been described. Some of the more recently developed paints such as Seal-Kote paint are capable of covering most surfaces with a single coat. However, frequently it is desired to apply the previously described mist coat. If the latter is the case a fourth pass is made across the surface and a covering coat is applied.

There has thus been described an improved liquid applicating device for high speed mechanical uniform treatment of large, unconfined surfaces of substantially constant cross section, and there has also been described a method of accomplishing this. treatment.

There has further been described a simple and novel technique for holding a plurality of spray heads in spaced relationship as they are moved across a surface to be treated and simple and easily constructed mechanisms for adjusting the spaced relationship of such spray heads.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the 8'", combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. A mechanical liquid applicator for applying liquid to a large unconfined smooth surface, of substantially constant cross section, said applicator comprising, 'a mobile frame, a plurality of spray heads carried by the frame, fluid conduits fixed to and communicating with each of the spray heads for conduction of liquid to be applied and atomizing air to the spray heads, control means operably connected to the spray heads to start and stop the operation of the spray heads, motive means connected to the frame to cause the frame and spray heads to move over such unconfined surface, and spacing means connected to the frame to hold the frame and the spray heads in spaced relationship with such surface, said frame, said spacing means, and spray heads having a center of gravity, said motive means being connected to said frame other than at the motive means connection such that a plane passing through such center of gravity and paralleling a surface being treated when the device is in operation will lie between said center of gravity and said spray heads, the frame being so supported to pivot about said connection and constantly apply pressure against said spacing means.

2. A mechanical liquid applicator for applying liquid to a large unconfined smooth surface of substantially constant cross section, said applicator comprising, a mobile frame, a plurality of spray heads carried by the frame, fluid conduits fixed to and communicating with each of the spray heads for conduction of liquid to be applied and atomizing air to the spray heads, control means connected to the spray heads to start and stop the operation of the spray heads, motive means pivotally connected to the frame to cause the frame and spray heads to move over such unconfined surface, spacing means connected to the frame to hold the frame and the spray heads in spaced relationship with such surface, and a counterweight fixed to the frame, said motive means being connected to said frame between said counterweight and said spacing means, said counterweight serving as a moment of force, and said motive means connection being a fulcrum about which the frame may pivot to apply a constant pressure against said spacing means.

3. A mechanical liquid applicator for applying liquid to a large unconfined smooth surface of substantially constant cross section, said applicator comprising, a mobile frame, a plurality of spray heads carried by the frame, said spray heads being pivotally adjustable relative to the frame to permit selective direction of fluid emitted from said spray heads, fluid conduits fixed to and communicating with each of the spray heads for conduction heads to start and stop the operation of the spray heads,

means pivotally connected to the frame to cause the frame.

and spray heads to move over such unconfined surface, and spacing means connected to the frame to hold the frame and the spray heads in spaced relationship with such'surface against movement of said frame about said pivot.

4. In combination to form a liquid applicator for applying liquid to a large unconfined smooth surface, said applicator comprising, a mobile frame, a plurality of spray 'heads'carried by'the frame, an air compressor, a first flexible conduit connecting said compressor to said spray heads, a control valve forming a portion of said first conduit to selectively turn said spray heads on and off simultaneously, a liquid reservoir, a second flexible conduit connecting said reservoir to said spray heads to conduct liquid under pressure to said spray heads and to return excess liquid to said reservoir, a third flexible conduit connecting said air compressor to said spray heads to provide atomizing air under pressure to the spray, heads in preselected spaced relationship with such unconfined surface, and yieldable means to cause the spacing means 'to move relative to the motive means and thereby to constantly urge the spacing means against the surface, beintreated"; .1 it i 5. A mobile ipain tingQLViQcomprising, a truck including a flat bedfasupport carried by the bed, a frame pivotally'carried by the support, said frame having a first sectionon one side .of the pivot and a second sec tion on the other side ofthe pivot, a plurality of spray heads fixed to the first frame section, a spacing wheel carried by, the' first frame section, urgingmeans connected to the second frame section to urge said frame about said pivot and thereby to urge said wheel into continuous contact with a surface to be painted, a liquid reservoir carried by said truck to provide a quantity of liquid to said spray heads, and a compressor transported by said truck, said compressor being in communication with said spray heads to control the operation of said spray heads.

6. A mechanical liquid applicator for applying liquid to a large unconfined smooth surface of substantially constant cross section, said applicator comprising, a mobile frame, a plurality of spray heads carried by the frame, fluid conduits fixed to and communicating with each of the spray heads for conduction of liquid to be applied and atomizing air to the spray heads, control means operably connected to the spray heads to start and stop the operation of the spray heads, motive means connected to the frame, to cause the frame and spray heads to move over such unconfined surface, and spacing means connected to the frame to hold the frame and the spray heads in spaced relationship with such surface, said frame having a plurality of relatively adjustable segments to place said spray heads in position to eject liquid in a pattern conforming in cross section to the cross section of the surface to be treated, said segments being individually adjustable relative to each adjoining segment about the axes substantially normally to a surface to be treated. I

7. A liquid applicating device for applying liquid to an unconfined surface of substantially constant cross section comprising, a frame having first and second vertical extremities, a plurality of spray heads carried by the frame, said frame and spray heads being adjustable to vary the relative positions of the spray heads to conform to the cross section of such surface, said frame including at least two longitudinally adjustable arms, a spacing wheel mounted on each of said arms at said first vertical extremity, said frame including-at least two support connection sections, said connection sections having an axis about which the entire device may pivot, said frame having a center of gravity between said first and second vertical extremities, said axis being located between parallel vertical planes passing through the center of gravity and said wheels when the device is in operation, whereby said device may be moved along a substantially vertical surface and the device will tend to pivot about the support axis to keep the wheels in contact with such surface and the spray heads in spaced relationship therewith and whereby said longitudinal arms may be adjusted to vary the spaced relationship of the spray heads and the surface.

8. A liquid applicating device for applying liquid to an unconfined surface of substantially constant cross section comprising, a frame having first and second vertical extremities, a plurality of spray heads carried by the frame, said frame and spray heads being adjustable to vary the relative positions of the spray heads to conform to the cross section of such surface, said frame in cluding at least two longitudinally adjustable arms, a

W10 spacing wheel mounted on each of said arms at-said first vertical extremity,said frame including at least two support connection sections, said connection sections having an axis about which the entire device may pivot',

said frame having a center of gravity between said firstand-second vertical extremities, said axis being located between. parallel vertical planes passing through the center of gravity and said wheels when the device is in operation, a hoisting mechanism, and a hoisting line connected ,to each of said connection .sections when the device is in operation, said hoisting lines being connected to said hoisting mechanism, said hoisting mechanism being at least in part locatable at the top of a vertical surface to which liquid'is to'be applied, whereby gravity may be utilized to lower the frame under control of the hoisting mechanism and whereby the frame-will tend to, pivot. about the. 'support axis when the device is inoperation to maintain the wheels in contact with the surface and the spray heads in spaced relationship therewith. 1

9. A liquid applicator for movement along an unconfined surface of substantially constant cross section, said applicator comprising, a mobile frame having a plurality of adjustable segments, said segments being individually adjustable relative to each adjoining segment about axes substantially normal "to a surface being treated, a spray head mounted on each segment, and means to hold the spray heads in spaced relationship with a surface to be treated, whereby the frame and spray heads may be adjusted to conform to a surface to which a liquid is to be applied and the device may be moved along such surface with the spray heads held in spaced relationship.

10. A liquid applicator for movement along an unconfined surface of substantially constant cross section, said applicator comprising, a mobile frame having a plurality of adjustable segments, a pivotally adjustable mounting arm carried by each of the frame segments, a plurality of pivotally adjustable spray heads, each spray head being carried by one of said arms, each said spray head being adjustable about an axis of adjustment of the mounting by which it is carried, said segments being individually adjustable relative to each adjoining segment about axes substantially normal to a surface being treated, and means to hold the spray heads in spaced relationship with a surface to be treated, whereby the frame and spray heads may be adjusted to conform to a surface to which a liquid is to be applied and the device may be moved along such surface with the spray heads held in spaced relationship.

11. A mobile liquid applicator device comprising, a frame, a plurality of liquid spray heads carried by the frame, conduction means connected to the spray heads to conduct a supply of liquid to the spray heads, liquid control means. operably connected to the spray heads to start and stop the flow of liquid through the spray heads, motive means connected to said frame to move the frame and spray heads along a path essentially paralleling the surface to be treated, tracking means carried by the frame and fixed relative to said spray heads, and means operably connected to said tracking means to urge said tracking means and spray heads relative to said motive means and yieldably against such surface to be treated.

12. A mobile liquid applicator device comprising, a frame, a plurality of liquid spray heads carried by the frame, conduction means connected to the spray heads to conduct a supply of liquid to the spray heads, liquid control means operably connected to the spray heads to start and stop the flow of liquid through the spray heads, motive means pivotally connected to said frame to move the frame and spray heads along a path essentially paralleling the surface to be treated, and tracking wheels carried by said frame and urged against such surface to be treated by pivotal movement of said frame about said pivotal connection.

"I1 13. A mobile liquid applicator device comprisinga rame, a'plurality ofliquid spray heads carried by the: frame,'e0nduction means connected to the spray-heads to conduct a supply of liquid to the spray heads, 'liq'uid pivotal connection and thereby urge said wheels against the surface to be treated.

14. A mobile liquid applicator comprising, an auto-' motive vehicle, a frame carried by said vehicle, a plurality of spray heads carried by the frame, liquid supply means carried by the vehicle and operably connected tosaid spray heads to supply liquid to be dispersed, spray head, control means operably connected to the spray heads to start and stop the operation'of-the spray heads, tracking means carried by the frame and fixed relative to the spray heads, and yieldablelmeans operably' connccted to said tracking means to urge said tracking means relative to said vehicle and into yieldable contact with a surface to be treated.

References Cited in the file of this patent UNITED STATES PATENTS 1,910,674 Bramsen et al. May 23, 1933 2,279,686 Kerlin Apr. 14, 1942 2,367,594 Madison Ian. 16, 1945 2,370,780 'Crom Mar. 6, 1945 2,444,811 Crom July 6, 1948 2,744,494 Chappen May 8, 1956 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2,874,677 7 February 24, 1959 Alfred E. Braun et al It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters 1 Patent should read as corrected below.

Column 8, line 20, for "motive means. connection" read center of gravity line 21, for "center of gravity" read motive means connection I Signed and sealed this 28th day of July 1959.

E Attest:

I KARL H. AXL'INE ROBERT C. WATSON Attesting; Officer C'omnissioner of Patents