US 3840179 A
Description (OCR text may contain errors)
United States Patent [191 Krohn et a1.
[451 Oct. 8, 1974 1 1 SPRAY APPARATUS  Inventors: Duane D. Krohn, Arvada; Kenneth S E. Smith, Denver, both of C010.
 Assignee: Binks Manufacturing Company,
Franklin Park, 111.
 Filed: June 4, 1973  Appl. No.: 366,599
 US. Cl 239/1, 239/415, 239/420, 239/528, 239/536  Int. Cl B05b 7/08  Field of Search 239/1, 306, 414, 415, 418, 239/420, 527, 528, 536
Primary Examiner-Lloyd L. King Assistant ExaminerAndres Kashnikow Attorney, Agent, or Firm'-Gary, Juettner, Pigott & Cullinan 57 ABSTRACT Method and apparatus for spray application of multicomponent liquid systems characterized by a pair of opposed spray heads respectively angled inward and downward and inward and upward toward a common area, such that the spray patterns from the heads impinge one another at compound angles with respect to a horizontal axis to form a common pattern with uniformly mixed components. The spray heads are mounted in opposite quadrants between horizontal and vertical with respect to a common axis, and each head is inclined toward the axis to achieve mixing of the spray patterns in both horizontal and vertical planes. The arrangement of the spray heads allows for ready control over and easy adjustment .of the composite spray pattern.
10 Claims, 9 Drawing Figures PATENIEnnm 8l974 7 sum 10? 2 BACKGROUND OF THE INVENTION This invention relates to method and apparatus for spray application of multi-component systems, such as catalyzed and promoted liquid resin compositions.
In the spraying of polymeric liquids, with or without concurrent application of fiberous reinforcing materials, promoters and catalysts must be mixed with the polymer during application; pre-mixing of the components is impractical because of the short pot life of the mixture. Accordingly, many multi-component spray systems include a plurality of spray heads for spraying separate components or for injecting catalyst into a stream of promoted resin outside of the spray head. Typical spray apparatus of this type are described in the following US. Pat. Nos. 1,718,507; 2,433,463; 2,578,412; 2,787,314; 2,933,125; and 3,542,296.
A difficulty with many plural head spray systems is the inability to achieve complete and uniform mixing of catalyst with the liquid resin. As a result, uncured stria or soft areas may be found in the applied polymer. The use of side-by side or vertically spaced spray heads, one dispensing catalyst and the other promoted resin, has not proved practical because the quantity of catalyst is small in proportion to the quantity of resin emitted from the head, and the catalyst spray fails to adequately penetrate the resin spray. The problem is particularly magnified in so-called airless systems, wherein the material is atomized under hydraulic pressure, because the sprays are relatively soft and do not have the driving force of air atomized sprays. The problem is also encountered with fan sprays, even if one head is supplied with resin and catalyst and the other is supplied with resin and promoter. Upon impingement, the components of the respective fans tend to travel in parallel lines and to become striated when merging into a single fan, which inhibits thorough mixing of the components.
One proposal to improve catalyst-resin mixing resides in the provision of a gun having side-by-side promoted resin spray heads with a smaller catalyst spray head located therebetween. Such systems, however, have the disadvantages of complexity and the expense of the added spray head, and the resulting spray pattern is not always free of striations.
Another limitation in present multi-component fan spray devices is the inability to conveniently adjust the composite fan spray pattern about a central axis. In the case of portable or hand held guns, it is possible, although inconvenient, to rotate the whole gun about a central axis, but the rotation normally disturbs the mixing action of the sprays, which are designed to be operated from a fixed location with respect to a horizontal plane.
SUMMARY OF THE INVENTION The present invention overcomes the above problems with the provision of a two-headed spray apparatus from which the respective spray patterns impinge at compound angles to achieve mixing in both vertical and horizontal planes. The spray heads are located in opposite quadrants with respect to central horizontal and vertical planes and are inclined inwardly to intersect along a common axis or line. The intersecting droplets from respective atomized sprays each have two components of motion, which causes thorough intermixing of sprays and prevents striation. Particularly with airless sprays, complete'ancl uniform mixing occurs.
Preferably, the spray heads emit fan-shaped patterns which impinge and form a common fan pattern. Be-
cause of compound angle impingement, the respective particles or droplets converge toward one another and intermix within the fan pattern.
The present apparatus also accommodates adjustment of the common fan spray pattern around a central axis by parallel adjustment of the fan spray nozzles. Such adjustment does not disturb the thorough mixing of the sprays because the compound angle impingement occurs in all parallel positions of the sprays.
THE DRAWINGS FIG. 1 is a side view, partly .in elevation and partly in vertical section, showing a multi-component airless spray apparatus which incorporates features of the present invention;
FIG. 2 is a fragmentary front view of the apparatus shown in FIG. 1;
FIGS. 3 and 4 are, respectively, fragmentary side and top views of the apparatus of FIG. 1, furtherillustrating the spray patterns issuing therefrom;
FIGS. 5, 6 and 7 are schematic'views illustrating vertical sections of spray patterns achieved by parallel rotary adjustments'of the two spray heads or nozzles; and
FIGS. 8 and 9 are schematic representations, respectively, of spray patterns of prior art apparatus and of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is characterized primarily as a spray apparatus having two spray heads or nozzles positioned and angled in a particular fashion, and it will be understood that the means provided for mounting the spray heads and supplying them with suitable liquid components are not critical and may be varied to suit existing conditions. In the preferred embodiment, the spray-heads 10 and 12 are supported on a portable spray gun 14 having a longitudinal body 16 anda handle 18 depending downward from oneend of the body. A head fixture 20 is secured to the front of the body and supports the spray heads 10 and 12, as will hereinafter be more fully described.
A pairof adjacent inlets 22 and 24 are provided on the underside of the head fixture 20, said inlets being connected by, suitable fittings to respective flexible hoses 26 and 28 which lead to different sources of pressurized liquid components. One inlet is supplied with a first polymer component, usually a mixture of liquid resin and promoter, and the other inlet is supplied with a second polymer component, usually a catalyst or a mixture of liquid resin and catalyst. These separate components have relatively long pot lives, will remain liquid and will not set up in the gun, but will cureand set upon being mixed by spray application from the gun. If desired, an alternate pair of inlets 30 for the two components may be provided at the rear of the gun, and respective bores 32 in the body 16 extend longitudinally from the inlets 30 to the chambers 34 of the inlets 22 and 24 in the head fixture 20. It will be obvious that additional alternate inlets could be provided, with the inlets that are not in active use being plugged off.
The gun is capable of adjustably regulating respective separate streams of the two liquid components which enter at the inlets and are discharged separately through the respective spray heads and 12. This is accomplished by two separate inlet chambers containing respective valve mechanisms that extend parallel with each other and serve to regulate the two separate streams of material. One of the chambers with its respective valve mechanism is shown at 34, it being understood that since both fluid sections and their respective valve mechanisms are identical, only one thereof will be described for sake of brevity.
The chamber 34 is part of a longitudinal bore 36 in the head fixture which is open to the rear and contains valve means for regulating the supply of fluid to the spray head 10. A valve seat 38 having an apertured depression faces the chamber and is connected to an outlet port 39 leading angularly through the head fixture 20 to the spray head 10. A rod 40 is positioned centrally in the bore 36 and has an enlarged terminus or valve ball 42 at one end sealingly engageable with the valve seat 38.
The rod 40 extends through a sealing gland 44 carried in a compression-type fitting 46 on the other side of the chamber 34. Beyond the gland 44, the rod 40 carries a washer or annular collar 48 which is spring loaded toward valve closed position and slidably guided in a cylindrical bore in the fitting 46. The aforementioned assembly provides a seal around the axially slidable rod and prevents leakage of fluid from the chamber 34.
A trigger 50 is pivotally connected to the gun body at 52 near the handle, and the trigger has bifurcated lugs 54 which embrace the rod 40. A pair of adjustable locking nuts 56 are provided on the threaded end of the rod to complete the assembly. Movement of the trigger 50 toward the handle 18 causes the rod to move rearwardly and open the valve. It will be understood that the trigger operates two parallel valve mechanisms conjointly such that both valves are opened and closed at about the same time. The locking nuts 56 of the respective rods may be adjusted in different positions to cause either simultaneous or sequential opening and closing of the respective valves.
As shown in FIG. 2, the spray heads 10 and 12 are equally spaced from the central longitudinal axis A of the head fixture 20, and the heads are located in diagonally opposite quandrants between horizontal and vertical planes passing through said axis. The axes of the heads are also inclined toward the central axis preferably at equal angles, such that the head axesintersect on the central axis, as indicated in FIGS. 3 and 4.
The heads 10 and 12 preferably include airless spray tips or nozzles each having a cat-eye" or narrow slot outlet orifice 58 which causes liquid to be issued from each in a fan pattern. The orifices 58 are adjusted to be disposed parallel to one another; in FIG. 2 vertically, so that two vertical fan patterns issue from the tips, impinge upon one another, and form a common vertical fan pattern. as shown in FIGS. 3 and 4.
FIG. 9 illustrates the resulting spray patternof the present invention in comparison with the illustration in FIG. 8 of a conventional two stream spray pattern. FIG. 8 shows the spray pattern from a conventional two headed spray apparatus having a pair of parallel apertured fan spray heads l-I-l-I located along the same axis X-X, the heads being inclined toward one another to impinge and form a composite. pattern in a plane coincident with the central axis Z.Z between the heads.
As the particles from the respective sprays, indicated at v 89 and 61 converge, they are deflected along a single angle and tend to travel in straight parallel lines from the point of impingement. Since movement of the particles within the plane of the composite pattern is substantially parallel to the central axis Z-Z, the particles of the respective sprays tend to remain separated and thus form an unmixed and striated final spray pattern as indicated at and 62.
Referring to FIG. 9, the apparatus of the present invention provides a pair of converging spray patterns which are also directed inward toward one another. The central axes of the sprays converge toward one another and intersect the central longitudinal horizontal axis Z'Z'. In addition, however, the sprays originate on a diagonal DD' on oppositesides of axis Z'Z' in locations between the vertical axis X'X' and the horizontal axis Y'Y'. Thus, the particles of respective sprays converge toward the Z'-Z' axis in both coordinate planes of X'X' and YY.
In the case of fan spray patterns as shown in .FIG. 9, the particles of respective sprays converge in the ZZ' axis to form a composite spray pattern wherein the particles continue to converge in the X'-X' and YY' axes. The respective particles have two components of motion relative to the composite pattern, which results in greater mixing efficiency; in fact, completely uniform and thorough mixing as indicated at 63 in FIG. 9.
FIGS. 5-7 illustrate how the composite spray pattern may be adjusted about the central axis A without loss of aforementioned mixing benefits. In FIGS. 5 and 7, the apertures in the spray heads are adjusted in parallel to respective vertical and horizontal parallel positions to achieve, respectively, a vertically or a horizontally elongated fan spray pattern. It may be'seen that the separate spray patterns (represented by dot-dash lines) do not simply converge and travel in parallel; in each case, they converge in both horizontal and vertical planes because of the positioning of the spray heads. A similar result is achieved if the spray pattern is adjusted to an intermediate position between horizontal and vertical without loss of compound angle impingement, as shown in FIG. 6. The only important consideration for proper mixing is that the apertures not coincide with the same line and be maintained in parallel to allow the separate sprays to be coextensive at the line of intersection.
1. Apparatus for spraying first and second liquid components which react with one another upon mixing, comprising a pair of spray nozzle means, supportmeans for mounting said pair of spray nozzle means about a common axis, means for supplying one of said nozzle means with said first component and means for supplying the other of said nozzle means with said second liquid component, said spray nozzle means being supported in respective opposite quandrants between horizontal and vertical with respect to said common axis and inspaced relation thereto, said spray nozzle means having respective axes disposed on inclined paths intersecting said common axis, whereby the reactive sprays from the respective nozzle means intersect one another at compound angles externally of said spray nozzle means.
2. The apparatus of claim 1 wherein each of said spray nozzle means comprises orifice means for producing a fan spray, whereby the two fan sprays impinge to form a common fan spray moving in a plane coincident with said common axis, and wherein particles of the two sprays converge in the plane of said common fan spray.
3. The apparatus of claim 2 wherein means are provided for supplying one of said pair of spray nozzle means with a pressurized liquid containing a polymer, and means are provided for supplying the other of said spray nozzle means with a pressurized liquid containing a catalyst for said polymer.
4. The apparatus of claim 2 further comprising separate valve means for controlling each of said pair of nozzle means, and means for operating said valve means conjointly.
5. The apparatus of claim 2 wherein said nozzle means comprises a nozzle body and said means for producing a fan spray comprises a part rotatable in said nozzle body, said parts being rotatable in said bodies to maintain the two fan sprays in parallel relationship.
6. The apparatus of claim 2 wherein said pair of spray nozzle means are mounted on a common spray gun having a generally vertically disposed handle.
7. A spray gun for spraying first and second liquid components which react with one another upon mixing, comprising a spray gun body having a pair of liquid inlets therein and a handle, means for supplying one of said inlets with said first liquid component, means for supplying the other of said inlets with said second component, a pair of spray nozzles mounted on said body,
a pair of separate chambers connecting respective inlets to respective nozzles, separate valve means in each of said chambers, means for operating said valve means conjointly, said nozzles being directed generally through an unobstructed space toward a common axis and being mounted on said body in opposite quandrants between horizontal and vertical with respect to said common axis, said nozzles being arranged at compound angles with respect to said common axis to cause intermixing of the first and second components externally of said nozzles.
8. Method of simultaneously mixing and spraying a plurality of reactive components in a composite spray comprising the steps of spraying one of said components on an angle horizontally inward and vertically upward along a first axis, and spraying another of said components horizontally inward and vertically downward along a second axis substantially intersecting the first to cause the respective sprays to converge at compound angles with' respect to a common axis.
9. The method of claim 8 wherein the respective components are sprayed in the form of first and second fans coinciding respectively with first and second converging planes, and the composite spray is in the form of a third fan coinciding with a third plane and defined by the intersection of said first and second fans, and wherein particles of said one component converge with particles of said other component within the plane of said third fan.
10. The method of claim 8 including the steps of adjustably rotating the planes of said first and second fans along parallel lines to adjustably rotate the plane of said third fan;