US 3589612 A
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Description (OCR text may contain errors)
United States Patent William R. Shaffer Huntingdon, Pa.
Dec. 22, 1969 June 29, 1971 Prismo Universal Corporation Huntingdon, Pa.
 lnvenlor Appl. No. Filed Patented Assignee  MODULAR LIQUID SPRAY GUN 11 Claims, 11 Drawing Figs.
U.S.Cl 239/139, 239/412, 239/456, 239/000 lnLCl BOSb 1/24 FieldofSearch 239/150, 151,407,4l2,451,456,570,600,139
 References Cited UNITED STATES PATENTS 2,825,602 3/1958 Rabbitt 239/117 2,843,425 7/1958 Paasche... 239/412 X 3,537,653 11/1970 Jones 239/533 Primary Examiner-M. Henson Wood, Jr. Assistant ExaminerMichael Y. Mar Attorney-Karl W. Flocks ABSTRACT: A liquid spray gun which may be used in roadstriping equipment and which can be assembled from a group of modules or interchangeable units. Utilizing some modules in common and some modified modules a variety of configurations can be formed including single-gun, double-body, double-nozzle or heated gun forms.
PATENTED JUN29 197i SHEET 1 BF 3 21 15 FIG. 2.
INVENTOR. WILLLlAM R. SHAFFER BY KARL DC) FLOCKS A TTORME Y PATENTEUJUNZQIB?! 3,589,612
sum 2 0r 3 IN VEN TOR. W LLAM R. SfiAFFER 535: (A) FEOQKS A TTORNEY PATENTED JUN29lHH 3,589,612
sum 3 nr 3 IN VEN TOR.
WILLIAM RBHAFFER MODULAR LIQUID SPRAY GIUN SUMMARY OF THE INVENTION 1. Field of the Invention The present invention is related to road-marking equipment and more particularly to a paint spray gun of modular construction developed to fill several unique requirements for use on a highway centerline marking machine although its application need not necessarily be confined to this function.
2. Discussion of Prior Art Most spray guns now available are not designed for use in the extremely dirty environment of the highway marking operation where any holes, irregularities and adjusting devices soon are filled or rendered inoperative. The flat smooth surfaces of this gun are intended to permit easy mounting and cleaning.
Striping operations require a wide variation in paint flow rates for they are carried out from a slow walk to as high as 20 m.p.h. This, of course, requires a wide range of fluid tip sizes, more than are usually available in commercially available spray guns. Provision is made in the modular spray gun of the present invention by use of an insert to mount a variety of different tips.
Highway marking also requires the application of several colors of paint in a variety of patterns. For example, an inter mittent white stripe is frequently used, also parallel lines of white and yellow are sometimes required and almost all markings contain some combination of white and yellow in an alternating pattern. To place these markings with conventional spray guns, many guns are required, specifically one for each color for each line. This may require as many as eight spray guns in a cluster less than 20 inches wide with a resulting congestion of hoses, mountings, etc., which make this condition almost impossible to adequately maintain. This condition is improved by spray gun configurations built with modular parts described herein with the present invention.
SUMMARY OF THE INVENTION Basically the present invention is a spray gun of modular or interchangeable smooth interfitting parts allowing a variety of assembly configurations. In addition, it can accept a variety of fluid tip sizes and fan widths.
The modular construction of interchangeable units allows easy conversion to different types of guns including two-color, single-nozzle construction, multiple-nozzle construction, and heating units for spray guns used with hot materials such as thermoplastic materials.
BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in detail in connection with the accompany drawings in which:
FIG. 1 is an exploded view of a basic single-color, singlenozzle, modular spray gun of the present invention showing internal parts in the basic modular parts;
FIGS. 2, 3 and 4 are top plan, side elevational, and bottom views, respectively, of the spray gun of FIG. 1;
FIG. 5 is an enlarged sectioned view of the elevationalview of FIG. 3;
FIG. 6 is a perspective view of a two-color, double-barrel, single-nozzle form ofthe modular spray gun;
FIG. 7 is an exploded perspective of the lower portion of the spray gun of FIG. 6;
FIG. 8 is a sectioned view along line 8-8 of FIG. 7;
FIG. 9 is a partial rear view of one portion of the spray of FIGS. 6, 7 and 8;
FIG. 10 is an exploded perspective view of a lower portion ofa double-barrel, double-nozzle form of the spray gun;
FIG. 11 is a sectioned view ofa modular spray gun including heating units.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The spray gun of the present invention can be assembled from a group of modules into a variety of configurations. The basic form of the spray gun is shown in FIGS. I through 5 illustrated in exploded form in FIG. 1, in top, side and bottom views in FIGS. 24, and in an elevational sectioned view in FIG. 5. r
The basic form of the spray gun is a single-barrel, singlenozzle form for single-color use. The important modules are, from top to bottom, the operator body II, the packing body 12, the fluid body 13, and air cap adapter I4. Pairs of screws I5 and 16 are used to hold the modules together in assembled condition. As will be noted, the lower modules are assembled first and the upper modules added on in the preferred embodiment for convenience in placement of the screws in their countersunk positions.
Within the modules is an operator needle assembly formed of needle stem 17 having a valve 18 at its lower end and a piston 19 at its upper end. Piston l9 reciprocates stem 17 by movement within operator body I I when control airflow is admitted into chamber 20 through inlet passage 21 below piston 19. Cutoff of air pressure under the piston 19 allows spring 22 to lower stern I7 to place valve It in a seated position against fluid tip 23 which acts as a valve seat. Paint is admitted under pressure into inlet opening 24 to pass through fluid tip 23 whenever valve 18 is unseated by the raising of piston 19 by the admission of control airinto chamber 20. This paint then mixes with atomizing air which has been admitted through inlet 25 and fed through air cap adapter 14 around the periphery of fluid tip 23 in air cap 26. Thus the paint leaves the spray gun as a spray.
Alignment of stem 17 and thus of the whole operator needle assembly is maintained by packing body 12 containing packing retainers 27 and 28 concentric with each other and stem 17, and in turn each containing interfitting packing discs 29 and 30, respectively. The sets of discs 29 and 30 are separated by packing spring 31 to retain each of the sets of discs 29 and 30 in their respective packing retainers 27 and 28. Fluid tightness is maintained by various gaskets and O-ring retainers shown in FIG. 5. Air cap ring 32 holds air cap 26 to air cap adapter I4 and in its relationship to fluid tip 23.
A second configuration of a spray gun that may be assembled from a group of modules is illustrated in FIGS. 6 through 9 wherein is illustrated a double-barrel, single-nozzle form used for spraying two colors at alternate or separate times.
Each of the barrels contains modules as in the basic configuration consisting of an operator body II and a packing body I2. Attached below each of the packing bodies I2 is a modified fluid body 43. Both fluid bodies 43 are mounted on an adapter body 44 to which is mounted an air cap adapter 14, a similar unit to that in the basic spray gun configuration. Therefore, of the modules, parts which are used in the basic configuration are used here except for the modified fluid bodies 43 and adapter body 44. In addition, there is a modification in the operator needle assembly whereby stem 17 is shortened. This is because since this configuration operates with two colors and only one nozzle there must be a separate cutoff for each color and this cutoff cannot take place utilizing fluid tip 23 as a valve seat. Therefore, in this configuration, each modified fluid body 43 has only an inlet opening 45 for paint and contains a fluid valve seat 46 in its base. Valve 18 on a shortened stem 17 seats in valve seat 46 in accordance with the operation of the pistons 19 located in each of the operator bodies II located on the top of each of the barrels. A compressed air connection at inlet 47 in adapter body 44 leads to a passage passing beneath both fluid valve seats 46 and connects them to the fluid tip connected with air cap adapter 14 connected below adapter body 44. Another air inlet 48 channels air around the periphery of the fluid tip to produce atomizing air for spraying as in the basic single-barrel configuration. Although the needle assembly does not extend into the fluid tip in the double-barrel configuration, the air cap adapter I4 with attached fluid tip 23 and air cap 26 is the same as the basic single barrel configuration but does not produce the valving action therein. By proper configuration of air cap adapter 14 and fluid tip adapter 33, mounted in air cap adapter 14, a large number of different fluid tip and air cap combinations may be used, thus permitting a very wide choice of capacities for the various gun configurations.
Another configuration adaptable to the wide choice of capacities is the double-barrel, double-nozzle configuration shown in FIG. 10. in this case several spray guns can receive fluid from a common line which allows less hose connections to be used, thereby helping to alleviate some of the crowding of hoses when many spray guns must be aligned in a small area for side-by-side spraying. Again, operator bodies 11 are used (not shown) attached on packing bodies 12 which both contain pistons and packing retainers, respectively, as discussed previously with the other configurations. For this configuration, both packing bodies 12 are mounted on a square manifold 53 which receives paint through side opening 54. Manifold 53 has opposed openings on its top and bottom with a packing body 12 at each top opening and a modified adapter body 55 at each bottom opening, with an air cap adapter 14 attached to each modified adapter body 55. Each modified adapter body 55 has an inlet opening 56 to admit the air for atomizing the paint spray. As in the basic single-barrel con figuration the needle assembly again uses a normal length stem 17 and the valve 18 seats in the fluid tip 23 in each of air caps 26. in this way, although supplied paint from a single source, either of the spray gun nozzles may be shut off or controlled individually.
The operations of all configurations of this spray gun are similar. Needle valve 18 is normally kept in place of fluid tip 23 or valve seat 46 by spring 22, thus preventing any material flow. When air under pressure is admitted to the underside of the operator piston 19 the needle valve 18 is lifted offits seat, permitting fluid to move through fluid tip 23. When the air is exhausted, or shut off, spring 22 again moves needle valve 18 against its seat shutting off any flow. The fluid flowing through fluid tip 23 is atomized internally within air cap 26. The size of fluid tip 23 and air cap 26, and the ratio of air-to-liquid pressures determines the degree and quality of atomization as with other spray guns.
FIG. 11 is illustrative of still another configuration of a spray gun of the present invention. Although this figure shows modifications to the modules, this is done so as to illustrate that variations in the modules described in connection with other configurations still are within the scope of the present invention. But essentially the operator body 61 has operator spring 62 and operator piston 63 therein operated as described with operator body 11 and spring 22 and piston 19, respectively. Attached to operator body 61 is packing body 64 with a packing retainer 65 containing both sets of packing discs and spring therebetween as previously held by two packing retainers 27 and 28. At the opposite end of the spray gun is an air cap 66 surrounding a fluid tip 67 with a valve seat 68 to receive needle valve 69. This is all within the realm of modular construction but disclosing different embodiments of the modules previously described.
FIG. 11 is also included to describe a modular form of spray gun intended for use with very hot materials. Attached to packing body 64 is a heating body or manifold 71 having passages 72 to carry a hot flowing fluid to heat the material in passage 73. In addition, air cap 66 in the modification of this configuration may also have passages 74 carrying hot fluid for additional heating of the materialjust prior to its exit from the spray gun.
Modules described above may be used as shown herein or the components described may be used in other combinations in order to cut down on room required or hose connections. Also, additional components may be used with the configurations shown to increase the number of colors being used or the number of lines being put down in a road-striping operation. Also, variations in matters of detail of the modules will be apparent and may be made within the scope ofthe present invention.
What i claim is:
l. A modular liquid spray gun ofinterehangeable units coma needle valve assembly unit having a valve at one end and a piston adjacent its opposite end connected by a stem.
an operator body means in modular form adapted for receiving said piston end of said needle valve assembly and said piston,
a packing body means in modular form connected to said operator body means and having packing retainer means receiving and aligning said stem of said needle valve assembly extending therethrough,
fluid body means in modular form to receive the material to be sprayed and insert it in the spray gun,
air cap and fluid tip adapter means in modular form to connect a nozzle of the spray gun to said fluid body means and having an air cap attached to said air cap adapter means attached to said fluid tip adapter means,
each of said operator body means, packing body means, and
fluid body means being of separate block form.
2. The modular liquid spray gun of claim 1, further characterized by said stem extending said valve into said fluid tip and said fluid tip adapted for seating said valve when said valve is in the closed position.
3. The modular liquid spray gun of claim 2, further characterized by said fluid body means having a passage thereinto to admit air under pressure with a passage therethrough into said air cap adapter means around the periphery of said fluid tip.
4. The modular liquid spray gun of claim I, further charac terized by said packing body means having at least one packing retainer,
interfitting packing discs in said at least one packing retainer in two sets with said sets separated by a spring in said packing retainer.
5. The modular liquid spray gun of claim 1, further characterized by an additional group of operator body means, packing body means, and fluid body means with a needle valve assembly unit passing therethrough and connected in a like manner to the connection of said first mentioned operator body means, packing body means, fluid body means, and said needle valve assembly,
each of said fluid body means mounted on an adapter body means,
said air cap and fluid tip adapter means attached to the opposite side of said adapter body means from said fluid body means.
6. The modular liquid spray gun of claim 5, further characterized by each of said fluid body means having a valve seat at its base to receive said valve of said respective needle valve assembly.
7. The modular liquid spray gun of claim 6, further characterized by said adapter body means having an air inlet passage connecting the opening through each of said valve seats to said fluid tip,
and an additional air inlet passage in said adapter body means connected outside the periphery of said fluid tip.
8. The modular liquid spray gun of claim 1, further characterized by an additional group of operator body means, packing body means, and air cap and fluid tip respectively attached thereto, and with a needle valve assembly passing therethrough,
said fluid body means being a manifold having each packing body means mounted thereon,
terized by said fluid body means including passageways connected to a source of heated fluid positioned to heat the material to be sprayed received by said fluid body means. 1!. The modular liquid spray gun of claim 10, further characterized by said air cap and fluid tip adapter means including passageways connected to a source of heated fluid positioned to heat the material to be sprayed as it passes through said fluid tip and said air cap.