US2537038A - Triangular shaping jet for spray guns - Google Patents

Description

Patented Jan. 9, 1951 UNITED STATES P NT OFFICE TRIANGULAR SHAPING JET FOR SPRAY GUNS Application May 27, 1948, Serial No. 29,552

3 Claims.

This invention relates to spray guns for sprayv ing paint and like surface coating materials, and

particularly it relates to nozzle structures for pro- :ducing an elongated spray pattern.

In spray guns for applying surface coating inaterial such as paint, it is desirable that the spray nozzle form the discharged spray of paint into an elongated and generally rectangular1 form. and many diiferent arrangements have been proposed for attaining this desirable spray pattern, Many of these prior spray nozzles have made vof are termed wing jets that cause suppleinental air to be impinged upon opposite sides of the originally conical spray so as to change the form thereof and cause the paint to be deposited in a rectangular or elongated pattern. Many problems have, of course, been encountered in such control of the paint spray pattern, and among these problems is the tendency of the spray pattern to divide about midway between the ends of the elongated spray pattern. In

. prior structures it has been somewhat difficult to lcontrol the action of the supplemental air issuing from the wing iets, and it is therefore an important object of the present invention to simplify the application of supplemental air from the wing jets of a paint spray nozzle, and 'a related object is to enable more accurate control of the pattern-forming action to be attained. Other obiects related to the foregoing are to impart a new cross sectional characteristic to the supplemental air iets and to do this in such a way that the wing jets may be readily and easily manufactured.

Other and further obiects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show preferred embodiments and the principles thereof and what I now consider to be the best mode in which I have contemplated applying those principles. Other embodiments of the invention embodying the saine or equivalent principles may be used and structural changes may be made as desired by those skilled in the -art without departing from the present invention and the purview of the appended claims.

In the drawings:

Fig. l is a vertical cross sectional View of e spray head embodying the features of the invention;

Fig. 2 is an enlarged portion of the structure shown in Fig. 1;

Fig. 3 is a front elevational view of the nozzle structure shown in Fig. 2;

Fig. 4 is a cross sectional view taken substantially along the line 4-4 of Fig. 2;

Fig. 5 is a fragmentary view similar vto Fig. 2 and illustrating an alternative construction;

Fig. 5 is a fragmentary front elevational view of the structure shown in Fig. 5;

Fig. 7 is a cross sectional view taken substantially along the line 1 1 of Fig. 5; and

Fig. 8 is a diagrammatic view illustrating the spray pattern and the relationship of the wing jets.

The nozzle or spray head structure of the present invention may be utilized with different forms or type of s'oray guns, but as herein shown, the invention is illustrated as embodied in a spray nozzle Hi that is mounted in association with the adapter iitting il which associates the spray nozzle with a sprav gun body l2. The spray gun body i2 may constitute the body of a spray gun of the kind illustrated in my copending application, Serial No. 734,319, led March 17, 1947, but it should again be observed that the spray nozzle lll may be utilized in association with other types or kinds of spray guns. As shown in Fig. 1, the adapter fitting il has a paint supply pipe I4 eX- tended downwardly therefrom so that paint or other surface coating material can be supplied to the nozzle will hereinafter be described in detail. The adapter tting Il is secured on the forward end of the spray gun body l2 by means including a fastening bolt l5 and a connecting nipple le, and when thus associated, a main air supply passage li! of the spray gun body is associated with the various air passages of the adapter fitting li, Thus the adapter tting I! has a main air passage 2D that connects directly with the passage I8. while a supplemental air passage El in the adapter fitting Il connects to tbe passage le and is controlled by a needle valve 22 that forms a part of the spray gun.

The main air passage 2) of the adapter fitting El connects at its forward end with an jannular distributing groove 24 formed in the forward face of the adapter fitting l l, while the suplformed in this same forward face of the adapter fitting, it being noted that groove 25 is of a larger diameter than groove 24. Centered with respect to the grooves Z4', and 25, the adapter litting ll has an internally screw threaded axial opening 25 that opens through the forward face of the ntt'ing II and is utilized in mounting a portion vof the nozzle structure, as will hereinafter be described, and this screw threaded opening or passage 26 opens at its rear end into a vertical passage 2l to which the paint supply pipe Hi is connected.

The nozzle l includes an inner nozzle member 30 and an outer nozzle member 3i, and the inner nozzle member has a nipple at its rear end that is screw threaded into the passage The inner nozzle member 3b has a flange 39E* that covers the annular groove 2d, and a central axial passage SSP in the inner nozzle member extends through the nozzle member and terminates in an outer discharge tip SET. A conventional needle valve 33, that forms part of the spray gun, extends through the passage SElP to control the discharge opening at the discharge tip 30T, and hence the flow of paint or other surface coating material through the passage ttl? is controlled.

The outer nozzle member 3i has a forward wall 35 in which an opening 36 is provided centrally thereof, and the tip of the nozzle member 30 extends through the opening 3% in a spaced relation so that the primary air may be discharged about the tip 3ST for causing an aspirating and spray-forming action upon the paint. The forward wall 35 of the nozzle member 3| connects with a rearwardly extending tubular portion 37| that is concentric with the opening 36, and an attaching or retaining collar 38 is rotatably secured on the tubular portion 3l. This attaching collar 38 is adapted to be threaded onto the threaded forward portion of the adapter fitting to hold the outer nozzle member Si in place as shown in Fig. l. In this connection it should be observed that the outer edge of the flange Si?? of the inner nozzle member 3E? has a forwardly and inwardly tapered surface, and the cylindrical portion 3l of the outer member has a complemental tapered seat 38 formed thereon so that the seat 3Q acts on the tapered edge of the flange 38B' to hold the two members 353 and El in a predetermined relationship to each other. Fo wardly of the tap-ered seat 39, the outer nozzle member has another tapered seat it formed thereon, and this tapered seat is arranged to engage a complemental tapered seat di formed on a forward portion of the inner nozzle member Thus, the two tapered seat engagements afforded by the tapered seats .te and @El serve to afford a pair of annular distributing chambers. The first of these chambers is identiied as il!! in Fig. 1 and is disposed about the tip 3ST and rearwardly of the wall 35, and the primary air is supplied to this chamber i2 by a plurality of angular bores 3 formed through the inner nozzle 3s from the annular distributing passage E@ to the forward face of the nozzle member 3S. rllhe other of the two annular chambers is identified at lill in Fig. 1, and this annular chamber has supplementary air supplied thereto by a plurality of grooves 45 formed in the outer tapered edge of the flange SDF. These grooves l5 afford air passages from the annular orroove .'25 past the tapered seat 39 and into the annular chamber lili.

The primary air supplied to the annular chamber 42 is discharged through an annular space afforded within the opening E@ and about the discharge tip 3ST so as to aspirato the paint or other surface coating material and discharge the same in a conical spray centered on theaxis of the discharge tip 3ST. This conical spray is modified as to form by supplementary air jets that are caused to impinge upon the opposite sides of the conical spray from wing jets B that are formed on the outer spray nozzle member 3|. These wing jets 50 have angular supply passages 5| formed therein as bores extending from the chamber 4t. The bores 5| terminate short of the ends of the wing jets 5u, and discharge ends are formed for the passages 5| so as to discharge the supplementary air in jets of such a form that they will act upon the conical paint spray to change the same from the circular cross sectional form indicated at lo in Fig. 8 to the elongated and generally rectangular pattern indicated at ii in Fig. 8. In accomplishing this action under the present invention, the discharge ends of the bores 5| are arranged so that the jets will be discharged in a triangular cross sectional form as indicated at 'i2 in Fig. 8. In accomplishing such control of the cross sectional form of the jets of air discharged from the wing jets 5S, the discharge ends are arranged so as to constitute passages that are of triangular cross sectional form, and this may be accomplished in different ways, as will hereinafter become apparent. Thus, as shown in Figs. 2, 3 and 4 of the drawings, angular bores 5s of circular form are made in wing jets 5@ so as to intersect with the supply passages 5| near the ends of the wing jets, and these bores 55E are arranged so that the axes thereof will intersect on the axis of the passage s6 a subst ntial distance forwardly of such passage 36. These bores Erl are utilized as a mounting for bushings that are mounted therein as by providing a drive fit. Each of the bushings 55 has a passage 5t formed therein and such passage 5S is in the form of a triangle. As herein shown, the triangle is an equilateral form, and one corner of the triangle is disposed s0 as to be adjacent to the axis of the opening 36. Thus, as will he evident in Fig. 3 of the drawings, the two openings 5E will be disposed with the corner that is adjacent to the opening 35 located in a common plane that passes through the axis of the opening 3%, while the opposite sides of these triangular openings t5 will in each instance be disposed perpendicular to such a plane. With the triangular passages 5S thus symmetrically related to the axis of the opening 36, the supplemental jets of air will be discharged therefrom in the relationship indicated at 'i2 in Fig. 8, and hence when the supplemental ,iets impinge on the opposite sides of the conical paint spray l0, the different parts of the jets or air will have a differential action that resu ts in a more uniform modification of the paint spray pattern. Thus it has been found that with the triangular discharge openings 56, disposed in the relationship illustrated in Figs. l te 3, the paint spray pattern is modified and converted to an elongated form as shown in Fig. S of the drawings.

The discharge openings may, of course, be formed in different ways, another way of accomplishing this is illustrated in Figs. 5 to 7 of the drawings. Thus in outer nozzle member Il, wing jets los are provided with supply passages iiii of the general type herein described, and these supply passages itil are each arranged to intersect with discharge passages 56 that are of triangular form and are disposed in the same way or relation as the passages 56. The passages 56, however, are afforded by forming relatively small bores in the wing jets |50, corresponding in general location to the bores 513. The shape of each of these bores is then modied by driving a suitable forming tool into such bore to change the shape thereof to the triangular form illustrated in the passages |56 in Figs. 6 and 7. The discharge passages |56 are effective in the same. manner as the passages 56 to impart the desired elongated form to the spray pattern.

From the foregoing description it will be apparent that the present invention enables the spray pattern of a spray gun to be converted into an elongated form in a simple and eiective manner, and it will also be clear that the employment of a triangular wing jet arrangement under the present invention assures gradual change of form of the paint spray so as to attain the de` sired elongated spray pattern without danger of splitting of the spray.

Thus, while I have illustrated and described the preferred embodiments of my invention, it is to be understood that they are capable of variation and modification and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim: 1. In a spray head for paint spray guns an the like, means affording air and paint supply passages for forming a conical spray of paint discharged forwardly along a predetermined axis, and means affording supplemental air discharge passages terminating in discharge openings of triangular cross section disposed on opposite sides of said axis for discharging supplemental air jets of triangular cross section against opposite sides of such a conical spray in symmetrical relation to said axis and said opposite sides of said conical spray.

2. In a spray head for paint spray guns and the like, means affording air and paint supply passages for for-ming a conical spray of paint discharged forwardly along a predetermined axis, and means affording supplemental air discharge passages terminating in discharge openings of triangular cross section and disposed on opposite sides of said axis with one side of each triangle disposed perpendicular to said axis so that s uch sides are parallel to each other and lie in a common plane, the corners of said triangles opposite said sides being disposed in a common plane passing through said axis.

3. In a spray head for paint spray guns and the like, means aiording air and paint supply passages for forming a conical spray of paint discharged forwardly along a predetermined axis, and means affording supplemental air discharge passages terminating in mounting bores disposed on opposite sides of said axis for discharging supplemental air jets against oppositefsides of such a conical spray in symmetrical relation to said axis and said opposite sides of said conical spray, and dischargesleeves secured in the respective bores and having longitudinal discharge passages formed respectively therethrough and of a triangular cross sectional form.

WILLIAM P. DALRYlVIPLE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date Re. 19,913 Paradise Mar. 3l, 1936 2,416,923 Jenkins Mar. 4. 1947 FOREIGN PATENTS Number Country Date 347,146 Great Britain Oct. 14, 1929

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