US3304013A - Spray nozzles - Google Patents

Description

Feb. 14, 1967 E. J. OBRIEN 3,304,013

SPRAY NOZZLES Original Filed May 1, 1963 2 Sheets-Sheet 1 E. J. OBRIEN SPRAY NOZZLES Feb. 14, 1967 2 Sheets-Sheet 2 Original Filed May 1 1963 f w X W. [5 4 M Z w Z! Z W 54; {M m V1 M 5 6 .0/ .02 .03 .04 .05 .06 7.46 .09 d Z J? 4 A6" a ./7 J6 United States Patent 3,304,013 SPRAY NOZZLES Edward J. OBrien, Glen Ellyn, 11]., assignor to Spraying Systems Co., a corporation of Illinois Original application May 1, 1963, Ser. No. 277,269.

Divided and this application June 3, 1965, Ser. No.

7 Claims. (Cl. 239-468) This application is a division of application 277,269, filed May 1, 1963, now abandoned.

This invention relates to spray nozzles of the kind wherein the liquid passes into a whirl chamber where rotating motion is imparted thereto and thereafter passes axially of the whirl chamber through a discharge orifice in the form of a hollow conical spray. More particularly the invention relates to spray nozzles of the aforesaid character wherein the whirl chamber is provided as a separately formed, and readily replaceable element.

In spray nozzles, of the type generally known as whirl spray nozzles, the discharge orifice is formed as a circular outlet coaxially formed at one end of a generally cylindrical whirl chamber. Water or other liquid is introduced tangentially as a high speed jet into the whirl chamber so that the liquid is given ahigh speed whirling movement within the chamber. This rapidly whirling liquid passes through the axially disposed orifice, and because of the whirling motion thereof, is emitted from the orifice as a hollow conical spray.

The nature of spray nozzles of the aforesaid character is such that there is a'whirlpool or cavitation effect that forms an elongated cavity or air column which desirably extends centrally through the spray orifice and through the Whirl chamber and to or substantially to the opposite or bottom wall of'the whirl chamber.

. It has been recognized for many years that uniformity of the hollow conical spray is dependent upon maintaining the whirling mass of water in a substantially centered or axial relationship with respect to thedischarge orifice. Conversely, a mislocated air column results in a poor spray pattern. Control of the location of the cavity or air column thus becomes essential to the production of the desired balanced spray.

Different devices have been employed for controlling the location of the cavity or air column in the whirling mass of water so as to obtain the desired balanced conical spray. One such device is shown in Wahlin Patent 2,247,897, patented July 1, 1941. In this structural arrangement, a central depression or pocket is formed in the bottom wall of the whirl chamber. This construction has been effective in creating the desired spray, but because it maintains the air column in a substantially same position at all times, a pronounced wearing action takes place in the area Where the air column engages the depression or pocket. As a result, a hole is ultimately produced through the bottom wall of the chamber.

Concentration of wear has required further structural modifications to be made in spray nozzles of the aforesaid character. One of such modification is the use of a removable bottom plug at the bottom of the central depression of the whirl chamber. The removable plug is conveniently made of a hard, wear-resistant material, and of course is periodically replaceable.

Another type of device that has been utilized to produce a conical spray pattern is that shown in Wahlin Patent 2,666,669. This patent discloses a whirl chamber comprising a cylinder having an orifice and a separately formed and readily replaceable fiat bottom wall. A tangential inlet is provided by forming a passage in the cylinder wall.

Still another device involved the use of a separately fihdfi l 3 Patented Feb. 14, 1967 formed Whirl chamber with an integral bottom wall, a tangential inlet near the bottom wall and a central recess or cavity in the bottom wall for maintaining the air column in the proper coaxial relationship. This separately formed whirl chamber was then held in place by compression spring means opposite a discharge orifice member and within a nozzle body. This last-mentioned structural arrangement has been widely used, but is burdened with the problem of excessive wear at the bottom of the centering pocket.

In view of the undesirable wear characteristics encountered in whirl chambers, efforts have been made to reduce the wear on the bottom wall of the whirl chamber by utilizing the teachings of OBrien Patent 2,815,248, patented December 3, 1957. In the aforesaid OBrien patent, the whirl chamber is formed directly in the nozzle body, and a portion of the bottom wall of the whirl chamber is formed as a fiat sloping surface. This sloping surface was found to have an advantageous controlling effect on the whirling water or other liquid within the whirl chamber, and a balanced hollow conical spray was produced, while at the same time minimizing the wear on the bottom of the whirl chamber. For many years those skilled in the art have tried to adapt the sloping bottom principle of the aforesaid OBrien patent to spray nozzles of the kind having removable and separately formed whirl chambers. These efforts showed that the production of a balanced hollow conical spray is critically related to the path of the liquid through the hollow inlet body of the nozzle, to the relative size and position of the tangential inlet of the whirl chamber to the slope of the bottom. Prior efforts to utilize the sloping bottom principle in this general type of spray nozzle have until the present invention, been unsuccessful.

It is the primary object of the present invention to provide a new and improved whirl spray nozzle of the sloping bottom type. An object related to the foregoing is the provision of such a spray nozzle wherein a slope bottom whirl chamber may be utilized in a removable or replaceable relationship While at the same time assuring the production of a balanced hollow conical spray.

More specifically it is an object of this invention to provide a spray nozzle utilizing a separately formed slope bottom whirl chamber element associated with other elements of the nozzle as an independent assembly that may be used in the same form with inlet bodies ofdifferent types.

Other and further objects 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 a preferred embodiment of the present invention and the principles thereof, and what is now considered to be the best mode in which to apply these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the invention.

In the drawings:

FIG. 1 is an enlarged vertical section taken through an exemplary spray nozzle embodying the features of the invention, the spray nozzle in this instance having an inlet body where the inlet passage is coaxial with the discharge orifice of the nozzle;

FIG. 2 is a plan view of a retainer member used to hold the Whirl spray chamber in place;

FIG. 3 is a side elevation of an exemplary, separately formed slope bottom whirl chamber, embodying the present invention and adapted for use in the nozzle of FIG. 1;

FIG. 4 is a transverse cross section of the whirl chamber of FIG. 3 taken along lines 44 thereof;

FIG. 5 is a section of the whirl chamber of FIG. 3 taken substantially along the line 5-5 of FIG. 4;

FIG. 6 is a view similar to FIG. 1 but in partial vertical section showing the invention embodied in the spray nozzle having a female type lateral connection for the inlet passage to the inlet body; and

FIG. 7 is a graph of the relationship between inlet orifice diameter and slope angle for a given whirl chamber of FIGS. 3-5.

Referring to FIGS. 1 and 6, there is shown a spray nozzle 10, constructed in accordance with the present invention.

For purposes of this description, the invention is herein disclosed as embodied in a spray head 11 of familiar construction, adapted for association with different types of inlet bodies 14, such as exemplified in FIGS. 1 and 6. As will be seen, the inlet bodies may be straight or angular, having either male or female outlet fittings. In accordance with the present invention, the spray head 11 receives a separately formed, slope bottom whirl chamber 15 in such a way that when assembled with an inlet body, a uniform and balanced hollow cone spray S is invariably produced.

As seen in FIGS. 1 and 6, the respective inlet bodies have a relatively large diameter bore 16 extending therethrough defining a liquid distributing chamber 20. In order to receive a spray head assembly, the lower portion of the bore is internally screw threaded at 22.

The inlet body 14 has a liquid inlet passage 24 opening through the back wall 26, coaxial with the distributing chamber 20. The upper portion of the passage is suitably internally threaded at 27.

The spray head assembly 11 comprises, in keeping with the invention, a cap having a reduced upwardly projecting (as seen in the drawings) nipple 32 that is externally threaded at 33 so that it may bescrewed into the threads 22. An upwardly facing shoulder 38 is formed about the lower end of the nipple 32 for receipt of a gasket 40 so that the cap may be sealed against the opposed surface 42 of the inlet body. The inner surface of the nipple 32 defines a mounting chamber 45 of conveniently greater diameter than the Whirl chamber 15. The chamber 45 has a reduced forward end portion 47 that has a diameter just slightly greater than the outer diameter of the whirl chamber 15. The reduced portion 47 terminates short of the lower face of the cap 30 so that a forward cross wall 50 is provided for the cap. In this cross wall 50, and coaxially with respect to the mounting chamber 45, a tapered bore 53 is provided through the wall, thereby providing a seat for a complementary sized orifice insert 55. The insert 55, in the illustrated form, has an outer tapered surface complemental to the tapered seat 53, so as to permit press fitting engagement and a central cylindrical opening 57 defines the discharge orifice for the spray head. As will be observed, the upper portion of the orifice opening 57 is formed with a shallow tapered countersink 60.

The slope bottomed whirl chamber 15 has a generally cup-shaped form, and is adapted to be placed in inverted relationship (FIGS. 1 and 6) in the mounting chamber 45 with its open, lower end, located in, and guided laterally by, the reduced portion 47. The transverse face of the wall of the open lower end of the whirl chamber 15 is substantially planar, and rests on the upper edge of the orifice insert 55. The closed, upper end (as seen in FIG. 1) of the whirl chamber 15 is engaged by removable T shaped retaining plug member 62 having its peripheral edge screw threaded to permit engagement with internal screw threads 64 formed on the nipple 32.

The retaining member 62 has an upstanding central cylindrical stem 66 that facilitates handling and insertion of the member in the nipple 32. A transverse slot 69 in the upper end of the stem 66 receives an appropriately shaped tool for tightening the member in position to hold tnue slope angle phi to the size of the inlet diameter.

4 the whirl chamber 15 against the orifice insert 55 in sealing relation, these elements together defining an independ-- ent assembly for receipt in an inlet body 14.

The member 62 has a plurality of flow stabilizing passages 71 (FIGS. 1 and 6) that extend downwardly therethrough in equally spaced circumferential relationship about the stem. In the present instance four such passages 71 are shown, but more or less may be used.

It will be noted that the height of the stem 66 is, in each instance, such that it terminates short of the upper wall of the inlet chamber 20, and the relative length of the nipple 32 is such that when the spray head 11 is associated with angular inlet bodies such as shown in FIG. 6, the upper end of the nipple is located at or downwardly from the lowermost portion of the lateral inlet passage permitting unrestricted flow of fluid to the chamber 20.

As shown particularly in FIGS. 3, 4 and 5, the separately formed whirl chamber 15 has a generallycup-like profile in section, and may be made by any suitable known process, but preferably from a hard material such as tungsten carbide or chrom carbide. The member 15 generally comprises a bottomwall and an integrally formed cylindrical side wall 82, together defining a cylindrical inner chamber 85. The inner bottom wall will be seen to slope, lying in a plane containing, for identification purposes, a line 87. The line 87 defines an acute angle phi with respect to another identification line 89 disposed perpendicular to the longitudinal axis AA of the chamber, and this angle is the true slope angle of the chamber bottom.

Extending through the side wall 82 of the whirl chamber, an inlet passage is formed. The passage breaks through the inner wall at a point 97, tangent to the side wall of the chamber so that liquid entering the passage is impelled about the smooth periphery of the chamber, thereby imparting a whi-rlingmotion.

In keeping with the invention, the inlet is disposed at short distance from the intersection of the side and bottom wall. Ideally, a distance between the axis of the inlet and the bottom of about 0.062 inch plus the radius of the in= let passage provides not only optimum wear characteris tics, but a stable and excellent spray pattern. On the drawings (FIG. 3) this dimension would be C. It has been found that variations from this dimension first re= sult in deterioration of wearability, but a certain amount is permissible in order to gain the manufacturing advan= tage' of forming the inlet on a jig using the same center for various diameters. Naturally, the smaller the diameter, the greater the distance C becomes.

Further, in keeping with the invention, the bottom surface of the chamber is formed so that the deepest portion thereof, shown in FIGS. 3 and 5 as a point 100, is located in a particular relationship with respect to the inlet passage 95.

With reference particularly to FIG. 4, in order to develop a desirable spray pattern, placement of the inlet must be proper with respect to the position of the shape of the slope. Thus, the axis, identified as line 102, of the inlet bore and the line 87 lying in the plane of the slope define an angle theta (0). This angle is preferably between 30 and 50, and ideally between 40 and 45. Variations within this range may be measured by dis placement of the highest point of the slope to the right or left of its indicated position, as'seen in FIG. 4 and identified as lines and 112. Lines 110 and 112 WhlCh pass through the highest point and the axis of the chamber thus define the position of the plane of the slope relative to the inlet hole 95.

Still another parameter is involved in achieving the desirable result of the present invention. Uniform spray patterns, as previously noted, arise through maintenance of a properly formed and positioned air core. Important to this performance factor is the relationship of the The ordinate is divided into units of 1 of slope, and the abscissa into units of equal length, defining units of 0.010 inch of orifice diameter. This relationship has been plotted, and appears as FIG. 7. It will be seen that a range of approximately 12 is permissible to obtain the desired results.

Specific measured relationship for optimum performance show that for an inlet diameter of .067 inch the angle phi is 2. This is point 120 on the graph. For greater capacity, the orifice diameter may be increased for example to a .096 inch and the slope angle phi becomes 3, point 122 on the graph. Likewise, a diameter of 0.109 inch relates to an optimum slope of 4", point 124 on FIG. 7. Broadly considered, as the diameter of the tangential inlet passage 95 is increased, the slope of the bottom surface is increased. As seen in FIG. 7, above orifices sizes of approximately 0.11 inch, the relationship approaches 1:1.

Orifice inserts 55 of different diameters are conventionally employed with any selected size of inlet opening 95 to obtain variations in capacity and spray angle, and this is influenced by the pressure in the liquid being sprayed. The range of diameters of the orifices often employed is from .055 inch to .250 inch, and by difierent oombinations of inlet diameter and orifice diameter a wide range of output capacities and spray angles may be obtained for the input pressure that is to be involved.

Referring again to FIGS. 1 and 6, it will be observed that when liquid enters the relatively large distributing chamber 20 there is a reduction in flow velocity. The liquid then flows axially through the several stabilizing flow passages 71 so that regardless of the direction of entry of the liquid into the distributing chamber 20, the flow of such liquid into the chamber 45 is the same. Such flow through the equally spaced stabilizing passage 71 is thus evenly distributed about the axis of the chamber 45, and the change of direction of flow that is required for this liquid to enter the tangential passage 95 remains the same regardless of the rotative position of the whirl chamber 15 within the chamber as determined by the tightening of the threaded cap into the inlet.

In the proportion shown in the drawings, the spray nozzles of all of the forms shown are such that even though liquid enters the chamber 20 at a relatively high velocity, the larger volume of the chamber reduces the velocity of the liquid to but a small fraction of the velocity at which it entered. Thus, in the chamber 20, the liquid has a relatively large pressure head and it has lost any directional characteristics of the velocity that it may have had as it entered. The relatively high pressure head causes the liquid to pass downwardly through the flow stabilizing passages 71 at a somewhat increased velocity, and the fiow is again balanced in the chamber 45.

Within the chamber 45. the downward velocity is again decreased, and in the proportion shown, the downward velocity is measurable at about one-third of the velocity of the liquid as it moves through the passages 71. Thus, regardless of the relative inlet direction of the inlet nassages, the liquid in every instance loses its original direction characteristics in the distributing chamber 20 and enters the chamber 45 in the same direction and in a balanced relationship about the annular chamber provided between the walls of the chamber 45 and the outside of the whirl chamber 15. This advancing liquid thus has the same characteristics of pressure flow direction and the like in every instance, and the liquid therefore is forced through the tangential passage 95 into the whirl chamber 15 in the same manner regardless of the direction of entry into the distributing chamber 20 and regardless of rotative relationship of the whirl chamber 15 within the chamber 45. Thus, uniformity of the resulting spray S is unefiected in any way upon the direction of the entry of liquid into the distributing chamber, nor is it dependent upon the rotative position of the chamber 15 within the chamber 20.

It will be apparent therefore that the present invention provides an improved spray nozzle structure wherein the wear-resisting capabilities of a slope bottom whirl chamber may be effectually utilized while at the same time assuring that the spray that is produced will be balanced in every instance.

It will also be evident that the present invention provides a new and improved spray head structure that is of great utility because it may be utilized in a single form for association with inlet bodies of diflerent construction.

Thus while a preferred embodiment of the invention has been illustrated herein, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit and scope of the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a spray nozzle, comprising a spray head assembly removably fitted to an inlet body, said spray head defining with said inlet body a relatively large cylindrical space, and having an outlet orifice disposed in one end thereof, a cup-shaped member adapted to be removably secured within said space with the open end thereof disposed about said orifice in overlapping relation, said cupshaped member and spray head together defining a generally cylindrical whirl chamber co-axial with said orifice, having side walls, and an integral bottom wall opposite said orifice, the plane of said bottom wall being oblique to the axis of said whirl chamber, an inlet passage formed through the wall of said cup member generally transverse to the axis of said chamber and terminating in said chamber adjacent to the intersection of the side' wall and said bottom wall so that fluid under pressure disposed in the portion of the space about said up member is forced into said chamber through said passage and against the side wall and sloping bottom adjacent thereto, causing a whirling helical movement of said fluid as the same passes through said orifice, in an evenly dispersed conical fan.

2. A whirl spray head assembly adapted to be received in an inlet body to form a whirl spray nozzle comprising in combination, a cap portion having a cross wall and defining a chamber therein, means defining an orifice centrally disposed in said cross wall, a cup-shaped member having a bottom portion and an integrally formed cylindrical wall together defining a generally cylindrical whirl chamber, said chamber being coaxially disposed in overlapping relation about said orifice and in unrestricted communication therewith, the bottom wall of said chamber opposite said orifice being disposed in a plane which is oblique relative to the axis of said chamber, means defining an inlet passage in the cylindrical wall of said member adapted to direct fluid into said chamber in a direction substantially tangent to the cylindrical wall of chamber and toward the lowest point of said sloping bottom wall so that the fluid flows in a helical path toward said orifice, and means fitted in said cap for holding said member in rigid alignment with said orifice.

3. A whirl spray head assembly adapted to be received in an inlet body to form a whirl spray nozzle comprising in combination, a cap portion having a cross wall and defining a chamber therein, means defining an orifice generally centrally disposed in said cross wall, a cupshaped member having a bottom portion and an integrally formed cylindrical wall together defining a generally cylindrical whirl chamber, said chamber being coaxially disposed in overlapping relation about said orifice and in unrestricted communication therewith, the bottom wall of said chamber being disposed in a plane which forms an acute angle relative to a plane transverse to the axis of said chamber, means defining an inlet passage in the cylindrical wall of said member adapted to direct fluid into said chamber in a direction substantially tangent to the cylindrical wall of chamber and toward the lowest point of said sloping bottom wall so that the fluid flows in a helical path toward said orifice, said angle of the plane of said sloping bottom wall being variable in direct proportion to the diameter of said inlet passage,

and means fitted in said cap for holding said member in rigid alignment with said orifice.

4. In a spray nozzle, comprising a spray head assembly removably fitted to an inlet body, said spray head defining with said inlet body a relatively large cylindrical space, and having an outlet orifice disposed in one end thereof, a cup-shaped member adapted to be remov-ably secured within said space with the open end thereof centrally disposed about said orifice in overlapping relation, said cup-shaped member and spray head together defining a generally cylindrical, smooth walled whirl chamber coaxial with said orifice having side walls, and an integral bottom wall opposite said orifice, the plane of said bottom wall being oblique to the axis of said whirl chamber, an inlet passage formed through the wall of said cup member generally transverse to the axis of said chamber and terminating in said chamber adjacent to the intersection of the side wall and said bottom wall, the slope of said bottom wall being generally upward toward said inlet passage whereby fluid under pressure disposed in the portion of the space about said cup member is forced into said chamber through said passage and against the side wall and sloping bottom adjacent thereto, causing a whirling helical movement of said fluid as the same passes through said orifice, in an evenly dispersed conical fan.

5. A whirl spray head assembly adapted to be received in an inlet body to form a whirl spray nozzle comprising in combination, a cap portion having a cross wall and defining a chamber therein, means defining an orifice generally centrally disposed in said cross wall, a cupshaped member having a sloping bottom portion and an integrally formed cylindrical wall together defining a generally cylindrical whirl chamber, said chamber being coaxially disposed in overlapping relation about said orifice and in unrestricted communication therewith, means de-- rection of said inlet passage, from a point therebelow, a

line in said plane between the lowest and highest point therewithin, said chamber defining with the axial center of said inlet passage, an acute angle, said inlet passage adapted to direct fluid into said chamber in a direction substantially tangent to the cylindrical wall of chamber and toward the lowest point of said sloping bottom wall so that the fluid flows in a helical path toward said orifice, and means fitted in said cap for holding said member in rigid alignment with said orifice.

6. The combination as set forth in claim 5 wherein said acute angle ranges between and 7. The combination as defined in claim 5 wherein the slope of the bottom wall of said chamber defines an acute angle with respect to a line transverse to the axis thereof, said angle being variable in direct proportion to the diameter of said inlet passage.

References Cited by the Examiner UNITED STATES PATENTS 2,218,110 10/1940 Hosmer et a1. 239468 2,247,897 7/1941 Wahlin 239-468 2,666,669 1/1954 Wahlin 239468 2,815,248 12/ 1957 OBrien 239-468 FOREIGN PATENTS 1,378,681 10/1964 France.

EVERETT W. KIRBY, Primary Examiner.

Claims (1)

1. IN A SPRAY NOZZLE, COMPRISING A SPRAY HEAD ASSEMBLY REMOVABLY FITTED TO AN INLET BODY, SAID SPRAY HEAD DEFINING WITH SAID INLET BODY A RELATIVELY LARGE CYLINDRICAL SPACE, AND HAVING AN OUTLET ORIFICE DISPOSED IN ONE END THEREOF, A CUP-SHAPED MEMBER ADAPTED TO BE REMOVABLY SECURED WITHIN SAID SPACE WITH THE OPEN END THEREOF DISPOSED ABOUT SAID ORIFICE IN OVERLAPPING RELATION, SAID CUPSHAPED MEMBER AND SPRAY HEAD TOGETHER DEFINING A GENERALLY CYLINDRICAL WHIRL CHAMBER CO-AXIAL WITH SAID ORIFICE, HAVING SIDE WALLS, AND AN INTEGRAL BOTTOM WALL OPPOSITE SAID ORIFICE, THE PLANE OF SAID BOTTOM WALL BEING OBLIQUE TO THE AXIS OF SAID WHIRL CHAMBER, AN INLET PASSAGE FORMED THROUGH THE WALL OF SAID CUP MEMBER GENERALLY TRANSVERSE TO THE AXIS OF SAID CHAMBER AND TERMINATING IN SAID CHAMBER ADJACENT TO THE INTERSECTION OF THE SIDE WALL AND SAID BOTTOM WALL SO THAT FLUID UNDER PRESSURE DISPOSED IN THE PORTION OF THE SPACE ABOUT SAID UP MEMBER IS FORCED INTO SAID CHAMBER THROUGH SAID PASSAGE AND AGAINST THE SIDE WALL AND SLOPING BOTTTOM ADJACENT THERETO, CAUSING A WHIRLING HELICAL MOVEMENT OF SAID FLUID AS THE SAME PASSES THROUGH SAID ORIFICE, IN AN EVENLY DISPERSED CONICAL FAN.

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