Fluidic scanner nozzle and spray unit employing same

Abstract

A fluidic nozzle of the scanner type has its outlet spray pattern skewed from its chamber axis (A) by an amount determined by the asymmetry of its outlet orifice (23, 33) about that axis. A spray assembly (70, 90) of such nozzles, such as a showerhead, can be designed using nozzles with selected pattern skew angles to achieve desired spray coverage. Indexing tabs (97) and slots (96) are used to angularly position the nozzles in the showerhead. A portion of each nozzle may be formed with the showerhead faceplate (71) as an integral piece.

Claims

1. A fluidic scanner nozzle comprising: an interaction chamber defined longitudinally between an upstream end and a downstream end and having a longitudinal chamber axis (A), first and second members secured and sealed together to define said interaction chamber therebetween, said first member including said upstream end and a first open end longitudinally opposite an inlet opening, said second member including said downstream wall and a second open end longitudinally opposite an outlet orifice, and wherein said first and second members are joined at said first and second open ends; said upstream end including a hemispherical downward facing surface having said inlet opening for receiving pressurized fluid and delivering the pressurized liquid as a jet into said chamber along said chamber axis; said downstream end including a hemispherical upward facing surface having said outlet orifice for issuing a substantially conical outlet spray of liquid droplets from said chamber into ambient environment; wherein said outlet orifice is asymmetric relative to said chamber axis to thereby skew the direction of the liquid outlet spray relative to the chamber axis; wherein the interaction chamber is configured to deflect said jet in three dimensions relative to said longitudinal chamber axis such that the jet, upon issuing from said outlet orifice, forms said spray pattern in a substantially conical configuration of liquid droplets about a spray axis; and wherein the nozzle is disposed in a first bore defined through a plate of a sprayer along with a plurality of said nozzles disposed in respective additional bores defined through the plate, wherein said first or second member includes an angular positioning tab projecting radially outward therefrom at a predetermined angular location about the chamber axis, and wherein said plate has at least one indexing slot defined longitudinally at the periphery of said first bore and arranged to receive and rotationally engage said positioning tab with said nozzle in an angular position determined by the angular location of said indexing slot.

2. The scanner nozzle of claim 1 wherein said outlet orifice is asymmetric about its centroid.

3. The scanner nozzle of claim 1 wherein said outlet converges in a downstream direction at an angle of convergence that varies with perimetric location about the orifice.

4. The scanner nozzle of claim 1 wherein the centroid of the outlet orifice is transversely offset from the chamber axis.

5. The scanner nozzle of claim 1 wherein said outlet orifice is configured as a conical frustum converging in a downstream direction.

6. The scanner nozzle of claim 1 wherein said upstream and downstream ends are configured as substantially spherical segments having respective bases at which said segments are joined.

7. The scanner nozzle of claim 1 wherein said second member is defined in and through a plate of a sprayer in which a plurality of said second members of a respective plurality of scanner nozzles are formed integrally therein in an array.

8. The scanner nozzle of claim 7 wherein said plate is a front plate of a shower head.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1A is a schematic illustration of a prior art fluidic scanner-type oscillator representing one condition during its operation.

(2) FIG. 1B is a schematic illustration of the oscillator of FIG. 1A representing another condition during its operation.

(3) FIG. 2 is a schematic illustration in longitudinal section of illustrating operation of a fluidic scanner oscillator of the present invention.

(4) FIG. 3 is a perspective view in longitudinal section of one fluidic scanner oscillator embodiment of the present invention FIG. 2.

(5) FIG. 4A is a top view in plan of the bottom portion of another embodiment of the scanner oscillator of the present invention.

(6) FIG. 4B is a view in longitudinal section of the scanner oscillator of FIG. 4A.

(7) FIG. 5A is a top view in plan of the bottom portion of another embodiment of the scanner oscillator of the present invention.

(8) FIG. 5B is a view in longitudinal section of the scanner oscillator of FIG. 5A.

(9) FIG. 6A is a top view in plan of the bottom portion of yet another embodiment of the scanner oscillator of the present invention.

(10) FIG. 6B is a view in longitudinal section of the scanner oscillator of FIG. 6A.

(11) FIG. 7 is a view in perspective from below of a showerhead of the present invention.

(12) FIG. 8 is an exploded view in longitudinal section of an embodiment of the showerhead of FIG. 7 employing fluidic scanner oscillators of the present invention partially molded into the showerhead faceplate.

(13) FIG. 9 is a partial perspective view from below in longitudinal section of the showerhead faceplate of FIG. 8 showing a bottom portion of a fluidic scanner oscillator of the invention molded into the faceplate.

(14) FIG. 10A is a top view in plan of the bottom portion of still another embodiment of the fluidic scanner oscillator of the present invention.

(15) FIG. 10B is a view in longitudinal section of the fluidic scanner oscillator of FIG. 10A.

(16) FIG. 11A is a top view in plan of the bottom portion of a further embodiment of the fluidic scanner oscillator of the present invention.

(17) FIG. 11B is a view in longitudinal section of the fluidic scanner oscillator of FIG. 11A.

(18) FIG. 12A is a top view in plan of the bottom portion of still a further embodiment of the fluidic scanner oscillator of the present invention.

(19) FIG. 12B is a view in longitudinal section of the fluidic scanner oscillator of FIG. 12A.

(20) FIG. 13 is an exploded view in longitudinal section of another embodiment of the showerhead of the present invention employing fluidic scanner oscillators of the type illustrated in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(21) Specific dimensions set forth below are by way of example for particular embodiments to assist in an understanding of the illustrated structure; these dimensions are not to be construed as limiting the scope of the invention.

(22) Referring specifically to FIG. 2 of the accompanying drawings, a fluidic scanner oscillator 20 comprises an interaction chamber 21 of substantially spherical configuration and having a longitudinal axis A. An inlet lumen 22 is disposed preferably concentrically about axis A and is typically connected to a source of pressurized liquid to deliver a jet of the liquid into the upstream end of the chamber. Substantially diametrically opposed to the inlet lumen is an outlet orifice or aperture 23 for issuing the liquid jet to the surrounding ambient environment through a short annular collar region 24 defined as a recess in the outer surface of the chamber wall and diverging from orifice 23.

(23) The periphery of outlet orifice 23 is configured as an irregular conical frustum converging in a downstream direction from the downstream end of the chamber with chamber axis A passing therethrough. The terminus of outlet orifice 23 is an angularly continuous edge of negligible axial length, as opposed to a lumen or passage having finite axial length. The convergence angle of the perimeter of orifice 23 varies angularly (i.e., as a function of perimetric location) such that it is asymmetrically disposed about its own centroid and about axis A. In the illustrated embodiment the maximum convergence angle ϕ of orifice 23 relative to axis A is approximately 49° and shown to the left of the axis in FIG. 2; the convergence angle is at a minimum, on the order of 1°, at the diametrically opposed location to the right of the axis in the drawing.

(24) As described above in connection with the scanning oscillator shown in FIGS. 1A and 1B, a portion of the periphery of the liquid jet that does not exit through outlet orifice 23 is fed back upstream alongside the jet to form a three-dimensional vortical flow pattern (i.e., a doughnut or toroidal shaped vortical flow) axially centered about the chamber axis A. Random perturbations in the flowing liquid cause the vortical flow in the toroid to become diametrically unstable such that the toroid transverse cross-section randomly increases along different angular sections thereof and correspondingly decreases in the toroid sections at correspondingly opposite sides of the chamber. The jet flowing through the chamber and toroid will be deflected away from the larger diameter portion of the toroid and, when so deflected, will cause the spray pattern produced by the jet at outlet orifice 23 to be deflected accordingly. The randomly oscillating deflection of the jet in chamber 21 causes the resulting oscillating outlet jet to break up into a generally conical pattern of liquid droplets about a spray axis that, in the absence of the asymmetry of outlet orifice 23, would be substantially coaxial with chamber axis A. However, as a result of the orifice asymmetry, the axis X of the scanning spray pattern egressing from chamber 20 is skewed (i.e., the spray pattern experiences yaw) relative to axis A by an angle θ determined by the orifice configuration and transverse position relative to axis A. Moreover, the conical spray pattern becomes asymmetrical as indicated by the nominal boundary line Y of the deflected spray pattern shown in the drawing.

(25) It should be noted that obtaining selected aiming is sensitive to the axial length of the outlet orifice relative to its transverse dimension. If the throat length is too short, the spray aim angle will not be achieved reliably. If the throat angle is too long, then the cone angle of the output spray will be reduced. Also, the entrance angle of the scanner outlet orifice in the particular example illustrated in FIG. 2 (i.e., 49°+1°=50°) must be considered: if the entrance angle is too small, then the cone angle of the spray will be reduced; if the entrance angle is too large, then the desired aim angle of the output spray may not be achieved. As examples of dimensions in embodiments successfully tested, axial lengths of the outlet throats ranged from 0.010 inch to 0.020 inch, and diameters of the downstream throat ends ranged from 0.039 inch to 0.044 inch. In order to effect different skew or aiming angles, the angle of the asymmetrically converging throat wall relative to the chamber axis varied along its periphery between 19° and 31° in one embodiment, between 49° and 1° in another embodiment, between 13° and 37° in a further embodiment, and between 1° and 14° in still a further embodiment.

(26) The ability to redirect the spray pattern axis X as a function of the asymmetry of outlet orifice 23 permits the spray pattern to be aimed as desired. More particularly, in a spray head having a flat front face at which the outlets of a plurality of scanner oscillators are coplanar, differently aimed coplanar oscillators can be positioned by the designer to achieve a wide variety of combined spray patterns and overall spray coverage.

(27) The oscillator 30 illustrated in FIG. 3 is functionally the same as oscillator 20 of FIG. 2 and is made in two parts, a top part 35 and bottom part 36, to define a generally spherical interaction chamber in two respective halves joined at their bases. Top part 35 includes an inlet connector 37 extending upstream from its top in which liquid inlet lumen or passage 32 to chamber 31 is defined. A hemispherical downward-facing surface of top part 35 defines the upper half of interaction chamber 31 and is bounded perimetrically by a depending cylindrical wall 39. An annular flange 38 projects radially outward from wall 39.

(28) Bottom part 36 has a hemispherical upward-facing surface defining the lower half of chamber 31 and has the oscillator's asymmetrical outlet orifice 33 and surrounding collar region 34 defined therethrough. The wall 40 of bottom part 36 includes an annular ledge 41 surrounding the rim of the lower half of chamber 31. At the radial outer extremity of ledge 41 the wall 40 extends upwardly as a cylindrical section 42, radially spaced from the chamber. The resulting annular space is configured for receiving depending cylindrical wall 39 of top part 35. With top part 35 and bottom part 36 thusly joined, the bottom edge of wall 39 abuts ledge 41. Similarly, the annular upper edge of wall section 42 abuts the bottom surface of ledge 41, and the circumferential inner surface of wall section 42 abuts the circumferential outer surface of wall 39. These abutting surfaces facilitate sealing between parts 35 and 36, either by tight fit abutment, the use of one or more grommets, silicone sealant or the like, or any combination thereof. The bottom surface 47 of wall section 42 projects radially outward from wall 40 and serves as a support flange for the assembly as described in connection with the showerhead of FIG. 13. An indexing or positioning tab 43 extends a short distance radially outward at a predetermined angular location on the periphery of wall section 42. Tab 43 permits oscillator 30 to be positioned in a predetermined angular orientation in a showerhead, or the like, as described hereinbelow in in relation to FIG. 13.

(29) The bottom hemispherical parts of fluidic scanner oscillators 45, 55 and 65, each of the general type illustrated in FIGS. 2 and 3, are illustrated in FIGS. 4A & 4B, 5A and & 5B and 6A & 6B, respectively. Each oscillator is molded into a sprayer unit 44, only a downstream portion of which is shown in these drawings, the planar bottom surface 50 of which is the face of the sprayer. Oscillator nozzles 45, 55 and 65 are substantially identical except for the configurations of their respective outlet orifices which are asymmetrically (or symmetrically for no skewing or yaw) contoured as described above to effect different aiming directions. Specifically, the outlet orifice in oscillator 45 is asymmetrically configured relative to the oscillator axis identically to the outlet orifice 23 in FIG. 2, such that the aim angle of the outlet spray is deflected downward to the right. The outlet orifice in oscillator 55 is symmetrical about the oscillator axis so that there is no deflection of the spray pattern axis from the oscillator axis. The outlet orifice in oscillator 65 is asymmetrically configured relative to the oscillator axis such that the aim angle of the outlet spray is deflected downward to the left.

(30) It will be appreciated that any number of oscillators can be thusly combined in a sprayer with their aim angles selected to effect a desired overall spray pattern. As an example, a showerhead 70 employing plural fluidic scanner nozzles of the present invention is illustrated in FIGS. 7, 8 and 9. Showerhead 70 comprises a faceplate 71 having a substantially planar front surface and with multiple spray openings 72 defined therein, each opening configured to issue a spray pattern from a respective fluidic scanner nozzle. The fluidic scanner nozzles are preferably arrayed in the circular faceplate 71 at different radial distances from the plate center to cooperate with the aiming angles of the scanner nozzles so that the resultant spray from the showerhead provides a widely distributed and uniform distribution of water droplets.

(31) The bottom parts 75 of fluidic scanner nozzles of the type illustrated in FIGS. 4A, 4B and 5A, 5B and 6A, 6B are molded as part of faceplate 71 and extend therethrough. In assembling the showerhead the top parts 76 of these nozzles, which are substantially similar to the nozzle top parts 35 in FIG. 3 without the positioning tabs 43, are placed in the faceplate 71 from above to join with and communicate with respective bottom parts 75. The faceplate is then placed in the showerhead housing 77 and secured and sealed therein by screws (not shown) extending through appropriate bores 79 defined through housing and into threaded bores 78 defined in the faceplate. Pressurized water is received via a showerhead inlet fitting 80 which is preferably made of a metal such as brass, or of plastic or the like, and is adapted to engage a fitting such as a standard ½-inch pipe fitting. The received water is delivered to the various oscillator nozzles via respective inlet connectors 81 formed as a portion of the upper parts 76 of the nozzles and which are configured similarly to connector 37 in FIG. 3. In this regard, when faceplate 71 is sealed in housing 77 there is an open volume or space above the faceplate that receives the pressurized water and serves as a manifold from which the turbulently flowing water is distributed to the connectors 81. Alternatively, housing 77 may be provided with fittings integrally formed therein to receive respective connectors 81.

(32) Instead of molding the bottom part of the fluidic nozzles as part of a showerhead faceplate, a plurality of fluidic scanner nozzles 85A, 85B, 85C of the type illustrated in FIG. 3 may be disposed as respective nozzle units in an appropriately configured faceplate 91 of a showerhead 90 as illustrated in FIG. 13. The bottom parts of three such nozzles are illustrated in FIGS. 10A & 10B, 11A & 11B and 12A & 12B, each shown to have a respective aim angle as described in connection with the embodiments illustrated in FIGS. 4A & 4B, 5A & 5B and 6A & 6B. The faceplate 91 has a plurality of bores 92 defined therethrough for receiving respective scanner nozzles 85. Each bore 92 includes an upper cylindrical section 93 of a relatively large diameter and a lower cylindrical section 94 of relatively smaller diameter, the demarcation between the sections being defined by an annular shoulder 95. Each nozzle 85 includes an annular support flange 98, configured similarly to support flange 47 of FIG. 3, and arranged to abut shoulder 95 when a scanner nozzle is fully longitudinally inserted into a respective bore 92. In this position the bottom portion of the scanner nozzle extends into the lower section 94 of the bore with the upper part of the nozzle residing in the upper bore section 93.

(33) One or more longitudinally extending indexing slots 96 are defined at different angular positions in the boundary wall of lower section 94 and are configured to longitudinally receive and angularly engage a indexing or positioning tab 97 extending radially from the outer wall of the bottom section of each scanner nozzle 85. Positioning tabs 97 are configured substantially the same as positioning tab 43 described in connection with FIG. 3. Insertion of a scanner nozzle 85 into any bore 92 is prevented unless the nozzle positioning tab 97 is angularly aligned and engaged with one of the indexing slots 96 defined in that bore. This permits a nozzle having a specific aim axis direction to have its location in the showerhead nozzle array predetermined, permits specific design and preselection of the overall pattern of the showerhead spray. In other words, oscillator nozzles having specific aim angles and be inserted into the faceplate in specific angular orientations to effect a desired three-dimensional combined outlet spray pattern for the showerhead.

(34) This scanner nozzle configuration and showerhead assembly and method of the present invention provide some significant advantages, including: 1. The simplicity of the scanner nozzle member geometry, which includes an essentially spherical interaction region with coaxial, opposed inlet lumen (i.e., power nozzle) and outlet orifice or throat, allows for simplified construction of scanner fluidic arrays. a. All of the scanner nozzle throats with the downstream half of the interaction regions can be molded in one piece of the showerhead. In this embodiment, the power nozzle and upstream half of the interaction region are molded individually for each nozzle. The component count is equal to the number of fluidic nozzles plus one, which greater than in some prior fluidic showerheads, but the components are much simpler to design, mold, and assemble. b. All of the scanner throats with the downstream half of the interaction regions can be molded in one piece of the showerhead and all of the power nozzles and upstream half of the interaction regions can be molded in one other piece of the showerhead. In this scenario, component count for the fluidics is two, no matter how many fluidics are included. This embodiment also allows each showerhead to be designed and built to whatever scanner fluidic geometry is best suited rather than using more or less standard components that are typical in prior fluidic showerheads. i. To facilitate the alignment of a large number of fluidic nozzles in the assembly, one of the components may be molded out of a flexible material to allow it to conform to the other hard plastic component. ii. To facilitate the alignment of a large number of fluidics in the assembly of the present invention and to allow aiming or bending of the fluidics into various aim angles, both of the components may be molded out of a flexible material to allow them to conform to each other and to a hard face or backing plate that holds prescribed aim angles. 2. The economy inherent in the manufacturing process for making the scanner nozzles and the showerhead nozzle assembly (i.e., the essentially spherical interaction region coaxial opposed inlet and outlet) provide the option of economically molding the downstream parts of the interaction regions in the one piece of the showerhead assembly. Since the inlet lumen and upstream half of the interaction region are molded individually for each fluidic, the assembly of the showerhead is simplified and the components are much simpler to design and mold.

(35) As described, the bottom parts of showerhead nozzles may be molded together economically in a single molding operation, and this rapid and economical fabrication method provides a showerhead or nozzle assembly that reliably generates sprays covering large coverage areas with uniform coverage across target area. The method and structure of the present invention thus provides a practical way to make the throat sides of the distinct scanner inserts in a scanner array in a single molded piece in commercially available “open and close” tooling, by providing arrays with selected aiming features molded into the throats of each scanner insert.

(36) The scanner fluidic nozzle geometry of the present invention does not require a large surface seal as is required in prior fluidic nozzles; rather the nozzle of the present invention is molded in two parts that are joined by a very simple cylindrical seal which is much more robust than a large surface seal.

(37) As noted herein, although the invention has been disclosed with primary application for a showerhead, the principles are equally applicable for and sprayer unit requiring area coverage of liquid spray.

(38) Having described preferred embodiments of new and improved fluidic scanner nozzles and sprayer assemblies employing same, it is believed that other modifications, variations and changes will be suggested to those skilled in the art in view of the teachings set forth herein. It is therefore to be understood that all such variations, modifications and changes are believed to fall within the scope of the present invention as defined by the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.