Scanner nozzle array, showerhead assembly and method

A new scanner fluidic oscillator is used in an economically manufactured fluidic showerhead or nozzle assembly 50, 198, 250, 400 which aims oscillating sprays from multiple scanner fluidics to spread water uniformly over a preselected coverage area. The scanner fluidics and showerhead of the present invention provide a pleasing spray pattern, droplet size, droplet velocity, and temperature uniformity at very low flow rates (i.e., 2 gpm or less) for showering. The scanner fluidics are provided in a plurality of distinct configurations for generating individually tailored scanning sprays having a selected scanning spray characteristics. The showerhead's front plate (e.g., 56, 200, 270, 454) is configured to support and aim the fluidic oscillators, optionally with indexing slots 802 configured to receive corresponding angular indexing tabs 800 on the fluidic oscillator inserts to orient and aim the spray from each fluidic oscillator (e.g., 172, 220,282, 530).

BACKGROUND

Field of the Invention

This invention relates to fluid handling processes and apparatus. More particularly, this invention relates to new methods and apparatus for fabricating fluidic oscillators or inserts and showerheads and other nozzle assemblies to improve their performance.

Description of the Related Art

Standard jet-type shower heads do not provide pleasing spray pattern, uniform droplet size, uniform droplet velocity, and temperature uniformity at very low flow rates (e.g., 2 gpm or less) for showering. Any fluidic showerhead can, in general, provide improvements over the prior art traditional showerheads. Most fluidic-equipped showerheads have very few spray generating openings and are, therefore, initially considered inferior by un-knowing consumers at stores where they cannot spray the showerhead before purchasing. Prior fluidic showerheads are also tricky to manufacture because of the difficulty in sealing of the fluidic passages. Prior fluidic showerheads also tend to be more expensive than conventional jet showers because of the number of component fluidics. A useful background and introduction to the nomenclature needed to understand this invention is provided in U.S. Pat. Nos. 6,938,835, 6,948,244, 7,111,800, 7,677,480, and 8,205,812, which patents are commonly-owned by the owner of the present application and cover a prior embodiment of the commonly-owned scanner fluidic oscillator, multiple fluidic enclosures, and methods of integrating fluidic geometry (exit geometry) into the housing of a fluidic device.

Fluidic inserts or oscillators are well known for their ability to provide a wide range of distinctive liquid sprays by cyclically deflecting, without the use of mechanical moving parts, the flow of a liquid jet. The distinctiveness of these sprays is due to the fact that they are characterized by being oscillatory in nature, as compared to the relatively steady state flows that are emitted from standard spray or shear nozzles.

U.S. Pat. No. 4,052,002 (Stouffer & Bray) shows in its FIGS. 5-7 some of the typical liquid droplet spray patterns that can be produced by fluidic oscillators (wherein the droplet patterns illustrated represent the droplets produced during one complete cycle of the cyclically deflected liquid jet). It shows what can be considered to be the essentially temporally varying, planar flow pattern of a liquid jet or spray that issues from the oscillator into a surrounding gaseous environment and breaks into droplets which are distributed transversely (i.e., in the assumed y-direction) to the jet's assumed, generally x-direction of flow.

Such spray patterns may be described by the definable characteristics of their droplets (e.g., the volume flow rate of the spray, the spray's area of coverage, the spatial distribution of droplets in planes perpendicular to the direction of flow of the spray and at various distances in front of the oscillator's outlet, the average droplet velocities, the average size of the droplets, and the frequency at which the droplets impact on an obstacle in the path of the spray).

A fluidic insert is generally thought of as a thin, rectangular member that is molded or fabricated from plastic and has an especially-designed, liquid flow channel (or a means for inducing oscillations in the liquid that flows through the channel) fabricated into either its broader top or bottom surface, and sometimes both (assuming that this fluidic insert is of the standard type that is to be inserted into the cavity of a housing whose inner walls are configured to form a liquid-tight seal around the insert and form an outside wall for the insert's boundary surface/s which contain the especially designed flow channels). Pressurized liquid enters such an insert and is sprayed from it. Appropriate selection of the arrangement of the oscillator's flow channel and its dimensions are seen, at a specified flow rate, to control the properties of the sprayed oscillating liquid droplets.

Although it is more practical from a manufacturing standpoint to construct these inserts as thin rectangular members with flow channels in their top or bottom surfaces, it should be recognized that they can be constructed so that their liquid flow channels are placed practically anywhere (e.g., on a plane that passes though the member's center) within the member's body; in such instances the insert would have a clearly defined channel inlet and outlet. For example, see U.S. Pat. No. 5,820,034 (Hess) and its FIGS. 3-4 which show a two-part, fluidic insert whose exterior surface is cylindrical so that this insert can be fitted into a similarly shaped housing.

Additionally, it should be recognized that these flow channels need not be of a uniform depth. For example, see U.S. Pat. No. 4,463,904 (Bray), U.S. Pat. No. 4,645,126 (Bray) and RE38,013 (Stouffer) for fluidic oscillators in which the bottom surfaces of these channels are discretely and uniformly sloped so as to impact the ways in which the sprays from these oscillators spread as the move away from the oscillator's outlet. There are many well-known designs of fluidic circuits that are suitable for use with such fluidic inserts. Many of these have some common features, including: (a) at least one power nozzle configured to accelerate the movement of the liquid that flows under pressure through the insert, (b) an interaction chamber through which the liquid flows and in which the flow phenomena is initiated that will eventually lead to the spray from the insert being of an oscillating nature, (c) a liquid inlet, (d) a pathway that connects the inlet and the power nozzle/s, and (e) an outlet or exit from which the liquid exits the insert in the form of a spray.

Despite much prior art relating to the development of fluidic circuits, the nature of the housings or enclosures that surround fluidic oscillators have not changed much over the years. For example, for automotive windshield washing applications (one of the first areas in which such fluidic inserts were extensively used) a typical housing's exterior shape is aerodynamically configured from its rear face to its front face in consideration of the fact that this housing will be mounted on an automobile's hood and in front of its windshield. In such a housing's front face is an especially configured cavity or cavities that accommodate, via a press-fit insertion, one or two, see U.S. Pat. No. 6,062,491 (Hahn), fluidic oscillators. Such housings can also be modified to accommodate a diverging stack of such oscillators; see U.S. Pat. No. 7,111,800 (Berning et al.). While one generally thinks of the enclosures for these oscillators as being of an almost totally enclosing nature, this need not be the case, see FIG. 3 from U.S. Pat. No. 5,845,845 (Merke et al.) which shows a “lid” for enclosing only the boundary surface of the oscillator in which the fluidic circuit is located.

Commonly owned U.S. Pat. No. 6,938,835 (Stouffer), assigned to the assignee of the present invention, relates to a three-dimensional (3-D) scanning nozzle operating in the liquid-to-air mode, and more particularly, to a 3-D scanning nozzle in which a single jet has long wavelengths so that slugs of fluid persist for greater distances from the nozzle, thereby providing superior cleaning for hard surfaces by impact and abrasion. Prior full coverage sprays have been accomplished by fluidic oscillators that sweep sheets (e.g. see Stouffer U.S. Pat. No. 4,151,955) or by mechanically traversing a sweeping jet over the target surface (as is done in the case of some headlamp washers). Many cleaning jets distribute energy by spreading the jet and rely on wand traversing to providing further distribution. Superior cleaning has been shown by sweeping-jets issued from a fan nozzle of the type shown in Stouffer U.S. Pat. No. 4,508,267 over that of a spread jet, with static (non-sweeping) nozzle on headlamp cleaning nozzles. According to the '835 patent, a single, concentrated jet that is time-shared over an area is superior to static, multi-jet nozzles that sweep just like a fan, so in order to obtain a full-coverage spray pattern that is also more uniform in both pattern distribution as well as droplet size, the '835 patent relies on a type of fluidic oscillator that produces a random scan in both radial and tangential directions. Thus, the patent features a full coverage area spray nozzle having a cylindrical oscillation chamber bounded by an upstream end plate and a downstream end plate. An inlet aperture in the upstream end plate is coupled to a source of pressurized liquid to be sprayed on the area, and an outlet aperture at the downstream end issues a jet of the pressurized liquid to ambient. In this patent, the cylindrical wall of the oscillation chamber is defined by a line revolved about an axial line passing through the inlet aperture and the outlet aperture. The oscillation chamber is adapted to support a basic oscillatory toroidal flow pattern which remains captive within the confines of that chamber. The toroid spins about its cross-sectional axis and is supplied with energy from the jet of liquid issued into the oscillation chamber. The toroidal flow pattern has diametrically opposed cross-sections which alternate in size to cause the outlet jet to move in radial paths and also in tangential directions and thereby moves in a different radial path at each sweep, whereby there is a random sweeping, or scanning, of the jet issuing from the outlet aperture over the spray area.

As fluidic oscillators continued to be used in more types of spray applications, the opportunity arose to re-examine and improve upon the design of their enclosures as a way to improve upon the overall spraying performance of nozzle assemblies which use fluidic oscillators. Recognizing the need for the development of improved enclosures and fluidic spray assemblies to more effectively and efficiently provide a wider range of desired spray distributions, U.S. Pat. No. 8,205,812 (Hester et al), assigned to the assignee of the present application, illustrates an improved fluidic device that operates on a pressurized liquid flowing through it at a specified flow rate to generate an oscillating spray of liquid droplets having desired properties. Hester's '812 device provides fluidic spray assemblies (i.e., fluidic oscillators with novel enclosures) that can provide specific types of desired sprays that had not been achievable with conventional fluidic technology. For example, Hester's '812 device provides a fan-shaped spray that uniformly covers a relatively large surface area (e.g., a 400 cm2area at a distance of 30 cm from the spray head's exit) with liquid droplets that have large diameters (e.g., >2 mm), high velocities (e.g., > or about 4 m/sec) and possibly pulsating frequencies that are in the range of perception by the human body (e.g., < or about 30-60 hertz). Such a device provides enclosures and fluidic spray assemblies that operate at low flow rates in shower head and body spray applications that can allow for reduced flow rates so as to yield significant water savings while still yielding sprays that provide the same tactile sensations as conventional shower heads as the sprays impact upon the skin of a user, while also providing enclosures and fluidic spray assemblies that are also ideally designed for an assortment of commercial cleaning applications.

There is a need for further improvements, however. Showerheads or nozzle assemblies which cost less to assemble and provide the ability to generate usefully shaped unconventional combined spray patterns are desirable, and greater reliability and service life (while providing hi performance sprays) is a long felt need. There is also a need for improved enclosures and fluidic oscillating sprays for shower head assemblies that can provide reduced energy consumption, while still yielding sprays that provide desired tactile sensations as they impact upon the skin of a user, as well as providing better directional control of the spray to permit control of the location of the areas being wetted by the sprays from such assemblies

SUMMARY OF THE INVENTION

In striving to improve the performance of various types of fluidic sprayers, applicants have discovered that there are significant opportunities to create and introduce new enclosures for these fluidic oscillators that appreciably improve their performance. Accordingly, it is an object of the present invention to provide improved enclosures and fluidic oscillating sprays for shower head assemblies that can provide reduced energy consumption, while still yielding sprays that provide desired tactile sensations as they impact upon the skin of a user, as well as providing better directional control of the spray to permit control of the location of the areas being wetted by the sprays from such assemblies.

Another object of the present invention to provide enclosures for fluidic spray assemblies that can make “less water” feel like “more water”, as by providing low flow rate sprays that provide the same tactile sensations as higher flow rates in non-fluidic sprays as they impact upon the skin of a user.

Still another object of the present invention is the provision of scanner spray assemblies having multiple outlet nozzles, with each nozzle having a preselected spray characteristic to produce improved showerhead patterns.

Another object of the present invention is the provision of scanner spray assemblies having multiple fluidic oscillators, wherein each oscillator incorporates an inlet power nozzle and an outlet selectively positioned with respect to the power nozzle to produce a preselected conical spray direction and angle.

Another object of the present invention is the provision of scanner sprayers having multiple fluidic oscillators with a minimal number of components to simplify molding and assembly procedures.

It is another object of the present invention to provide enclosures and fluidic spray assemblies that are suited both for shower massaging applications and non-massaging applications.

These and other objects and advantages of the present invention will become readily apparent as the invention is better understood by reference to the accompanying summary, drawings and the detailed description that follows.

The fluidic sprayer of the present invention, which is illustrated in its preferred embodiments as shower heads having multiple fluidic oscillator outlets producing selected spray patterns to provide all of the benefits of fluidic showerheads, with additional advantages in the provision of selectable spray characteristics and in improved manufacturing processes, and thus is generally directed to satisfying the needs set forth above and overcoming the disadvantages identified with prior art devices and methods. This is accomplished, in part, through the application in a showerhead of multiple 3-D oscillating scanner sprayers of the general type described in the commonly-owned Stouffer '835 patent discussed above, to provide multiple 3-D scanning, fluidic outputs, each providing a spray output that sweeps, or scans in a preselected conical pattern size and direction. For convenience, a showerhead incorporating the described conical spray pattern will be referred to herein as a scanner showerhead.

In its broadest aspects, the invention is directed to a method of fabricating a two-part fluidic oscillator for scanning sprayers, the steps comprising molding a hemispheric upper of an interaction region having an inlet nozzle, molding a hemispheric lower part of the interaction region having a corresponding outlet aperture and throat, and configuring the throat to produce a selected outlet scanning spray having a predetermined conical outlet spray direction and axis. Further steps include selectively offsetting the throat with respect to the axis of the corresponding opposed power nozzle by varying the outlet throat angles. For use in a showerhead or the like, the process includes providing a scanning sprayer with multiple fluidic oscillators, and providing each fluidic throat of the sprayer with a selected offset, with any combination of offsets being utilized to produce a desired overall spray pattern. The sprayer is completed by enclosing components of the oscillator circuits in a housing having a rear portion and a front panel forming an enclosed fluid plenum.

A scanner sprayer device incorporating a two-piece fluidic oscillator in accordance with the invention includes a hemispheric upper part of an interaction region having an inlet power nozzle and a hemispheric lower part of the interaction region having a corresponding outlet aperture and throat. The throat is configured to produce a selected outlet scanning spray having a predetermined conical outlet spray direction and axis. More particularly, the throat of the lower part opposes the inlet power nozzle of the upper part and is selectively offset with respect to the axis of the opposed power nozzle by the angle of the outlet throat. In this device, the hemispheric upper part and the hemispheric lower part are joined to form a two-piece fluidic oscillator chamber. A housing having a rear portion and a front panel form an enclosed fluid plenum, wherein the upper part is in fluid communication with the fluid plenum by way of the inlet power nozzle to lead fluid into the fluidic oscillator chamber, and wherein the opposed outlet throat of the lower component is in fluid communication with ambient by way of the outlet aperture and throat. The throat of the lower part opposes the inlet power nozzle of the upper part and is selectively offset with respect to the axis of the opposed power nozzle by the angle of the outlet throat. To form a showerhead or other spray device, the scanner sprayer further includes multiple fluidic oscillators having selected offsets to produce multiple outlet sprays each individually controllable by the selection of the offset for producing a composite scanning spray pattern.

In accordance with additional aspects of the present invention, a fluidic device is provided that operates on a pressurized liquid flowing through it at a specified flow rate to generate an oscillating spray of liquid droplets into a surrounding gaseous ambient environment, with the spray having preselected desired properties, such as a conical spatial distribution and cone angle, as well as the velocity, frequency and wavelength of liquid droplets in front of the device. The scanner sprayer of the invention includes a plurality of fluidic oscillators, each having a fluidic circuit for inducing oscillations in pressurized liquid that flows through the oscillator so as to emit a liquid jet in the form of a scanning conical spray of liquid droplets, the spray having preselected features such as its direction and cone angle. A housing encloses the fluidic circuit, the housing having an exterior surface that includes a front portion, or plate, with a center-point, a rear portion, or plate, and an intermediate boundary surface that connects the front and rear portions to define an interior plenum. The fluidic circuit includes a plurality of passages receiving a corresponding one of the plurality of fluidic oscillators, with the intersections of the passages with the housing front plate defining a plurality of spray outlets. The geometrical arrangement of these outlets in the housing front face is chosen so as to achieve the desired properties of the scanning spray when the device is operating at its specified flow rate. Among its many advantages, the fluidic circuit geometry of the present invention provides preselectable spray directions and angles from the spray outlets, and further simplifies the manufacture of such devices by facilitating the molding and assembly process. Further, the geometry of the device of the invention does not require a large surface seal like prior fluidic assemblies, since the assembly in some embodiments of the invention is molded in two parts that are joined by a very simple cylindrical seal. The cylindrical seal is much more robust than a large surface seal, as will be described.

In broad terms, then, the present invention is directed to scanner-type sprayer devices, such as showerheads or the like, that incorporate two-piece oscillator chambers formed with opposed upper and lower components which, when assembled, produce a fluidic oscillator chamber. The upper component is in communication with a fluid plenum chamber by way of an inlet power nozzle which leads fluid through an upper wall portion of the oscillator chamber, while the opposed lower component is in fluid communication with ambient by way of an outlet aperture and throat leading through a lower wall portion of the oscillator chamber. The power nozzle is aligned with an axis of the oscillator chamber, while the opposed outlet aperture is offset from this axis a selected amount. Fluid under pressure enters the chamber though the power nozzle and circulates in the chamber, which in the illustrated embodiments is preferably generally spherical, to create a fluidic oscillation such as that described in the above-referenced U.S. Pat. No. 6,938,835. Fluid from the oscillation chamber is ejected in a variable-direction spray that scans randomly across a selected area that is defined by the conical outer shape of the spray pattern, with the direction of the spray cone and its conical angle depending on the geometry of the outlet aperture and throat and thus by the amount by which the outlet aperture is offset from axis of the power nozzle. This geometry and offset is preselected for each fluidic oscillator in a scanner sprayer so the cumulative effect of all the spray outlets produces a desired overall scanner spray pattern. Each spray cone may have a different geometry, or they may be all the same, or any combination may be used to produce the desired overall sprayer effect.

In accordance with the present invention, then, there is disclosed a scanner sprayer having a housing which receives a front plate to define a fluid plenum. Mounted in the front plate and having inlet power nozzles in fluid communication with the plenum and outlet throats in fluid communication with ambient are a plurality of fluidic oscillator circuits that generate scanner sprays having preselected characteristics such as direction and conical angle to produce a selected sprayer pattern having desired droplet sizes and uniformity as are particularly desirable in body sprayers and showerheads. In the disclosed embodiments of the invention, the oscillator circuit has a two-part configuration for ease of manufacture, with the parts being joined during assembly of the sprayer to form a generally spherical fluidic oscillator interaction region. An upper part of the circuit incorporates an upper hemispherical half of an oscillator interaction region and a single inlet power nozzle which is upstream of the interaction region and supplies under pressure a fluid to be sprayed. A lower part of the circuit incorporates a lower hemispherical half of the interaction region and a single outlet aperture and outlet throat through which fluid is ejected in a selected 3-dimensional scanning spray pattern to ambient.

In a first embodiment, the lower half of the fluidic oscillator circuit is formed, as by molding, in a lower front plate for the sprayer, with the front plate incorporating a preselected number of substantially hemispherical depressions incorporating outlet apertures and defining the lower half of the fluidic circuit. The upper half of each circuit is formed by a corresponding insert which incorporates a substantially hemispherical dome and incorporates the oscillator power nozzle, and which is partially inserted and secured in the lower front plate depression. A top housing component contacts at a sealed joint the top surface of the front plate and forms a plenum which encloses the oscillator circuit inserts. A fluid under pressure supplied to the sprayer enters the plenum and is distributed through the power nozzle of each oscillator circuit to the corresponding interaction region. This fluid circulates in the spherical interaction region and generates oscillations in the fluid, causing the fluid to be ejected as a conical scanning spray having characteristics of axial direction and cone angle determined by the location of the outlet with respect to the axis of the corresponding power nozzle.

Another embodiment of the invention incorporates a two-piece oscillator circuit insert, wherein a top half includes a power nozzle leading into a hemispherical dome and a bottom half includes a hemispherical depression incorporating an outlet aperture and throat. The sprayer includes a front plate having multiple openings for receiving the inserts, and a back plate, or housing top component, which is secured to the front plate to enclose the inserts in a plenum and to force the inserts tightly into the front plate openings. Spacer posts on the top of each insert contact the inner surface of the housing top plate to securely position the inserts a to act as turbulence filters. In operation, fluid under pressure supplied to the sprayer enters the plenum and is distributed into the power nozzle of each oscillator circuit through spaces between the spacer posts and then into the corresponding interaction region. This fluid circulates in the spherical interaction region, as described above, and generates oscillations in the fluid, causing the fluid to be ejected as a conical scanning spray having characteristics of axial direction and cone angle determined by the location of the outlet with respect to the axis of the corresponding power nozzle.

In still another embodiment, multiple two-piece oscillator circuits for a scanner sprayer are formed, as by molding on a single layer of a front panel, all of the downstream halves of the interaction regions and their outlets and scanner throats. Similarly, the upstream halves of the interaction regions and all of their power nozzles are molded in another single layer of the front sprayer panel. In this embodiment, a third layer is provided to support the first two layers and incorporates corresponding fluidic circuit apertures for receiving the downstream halves of the oscillator circuits. The front panel is secured to a top housing member, or component, to form an inner plenum which surrounds the power nozzles. Once again, fluid under pressure supplied to the sprayer enters the plenum through the top housing member and is distributed into the power nozzle of each oscillator circuit through spaces between spacer posts at the power nozzles and then into the corresponding interaction region. This fluid circulates in the spherical interaction region, as described above, and generates oscillations in the fluid, causing the fluid to be ejected through the outlet throat as a conical scanning spray having characteristics of axial direction and cone angle determined by the location of the outlet with respect to the axis of the corresponding power nozzle.

In accordance with the method of the invention, each of the two-part fluidic oscillators is fabricated so that the inlet nozzles, hemispheric upper and lower parts of the interaction region and the corresponding outlet apertures and throats are configured to produce selected outlet scanning sprays having predetermined conical outlet spray directions and axes. This is accomplished in accordance with the invention by selectively offsetting the outlet throat with respect to the axis of the corresponding opposed power nozzle, with the offset being accomplished by varying the outlet throat angles. Each fluidic circuit of a sprayer is provided with a selected offset, with any combination of offsets being utilized to produce the desired spray pattern. The components of the oscillator circuits are enclosed in a housing having a rear portion enclosing an inlet plenum and a part of the circuit and a front panel incorporating the remainder of the circuit and its scanning spray outlets. Thus, the method includes selecting each spray outlet to have an offset with respect to its corresponding power nozzle axis to create a desired overall pattern, with, for example, all the individual sprays being directed in a narrow pattern, as might be desirable for a body spray, or selecting them to create a broader overall pattern as might be desirable for a showerhead.

This scanner nozzle member configuration and showerhead assembly and method of the present invention provides some significant advantages, including:1. The simplicity of the geometry of each of a multiplicity of fluidic scanner nozzles, wherein each fluidic nozzle includes an essentially spherical interaction region and opposed inlet lumen (power nozzle) and outlet orifice (throat) features that allow for simplified construction of scanner fluidic arrays.a. All of the scanner throats are located in the downstream half of the interaction regions and thus can be molded in one piece of the showerhead. Since such fluidic devices are typically made by plastic injection molding methods, those knowledgeable with such manufacturing methods will understand that such manufacturing methods impose constraints on the geometry of such devices, and the molding of the downstream portions of the interaction regions in one piece has significant advantages. In this scenario, the power nozzle and upstream half of the interaction region are molded individually for each fluidic, so that the component count for the fluidics is equal to the number of fluidics plus one. This is more than in a prior fluidic shower, but the components are much simpler to design, mold, and assemble, as will be illustrated below.b. Alternatively, all of the scanner throats for 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 scenario also allows each showerhead to be designed and built to whatever scanner fluidic geometry is best suited rather than using the standard components that are typical in prior fluidic showerheads.i. To facilitate the alignment of a large number of fluidics 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. Alternatively, 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 fluidics and the showerhead nozzle assembly—the essentially spherical interaction region's coaxial, opposed inlet (power nozzle) and outlet (throat)—provide the option to economically mold the downstream halves of the interaction regions in the one piece of the showerhead assembly, as discussed above. Since the power nozzle 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.

The scanner fluidic showerhead of the present invention contains many more spray orifices or openings (more fluidics) than are available with prior fluidic showerheads, thereby overcoming one of the perceived drawbacks for such prior fluidic-equipped showerheads. Further, the fluidic oscillator outlet sprays may incorporate various outlet geometries to produce individually selected spray directions and cone angles to produce a desirable overall spray pattern. The method of manufacture and configuration of the present invention provides an economical and very effective seal for fluidic circuits in the scanner fluidic showerhead assembly of the present invention. The scanner showerhead of the present invention need not be as expensive to make as prior fluidic showerheads because there can be fewer components as compared with prior fluidic showerheads.

Thus, there has been summarized above, rather broadly, the present invention in order that the detailed description that follows may be better understood and appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims to this invention. Accordingly, the above and still further objects, features and advantages of the present invention will become apparent upon consideration of the following detailed description of specific embodiments thereof, particularly when taken in conjunction with the accompanying drawings, wherein like reference numerals in the various figures are utilized to designate like components.

DESCRIPTION OF PREFERRED EMBODIMENTS

In broad terms, the present invention is directed to scanner-type sprayer devices, such as showerheads or the like, that incorporate two-piece oscillator chambers formed with opposed upper and lower components which, when assembled, produce a fluidic oscillator chamber. The upper component is in communication with a fluid plenum chamber by way of an inlet power nozzle which leads fluid through an upper wall portion of the oscillator chamber, while the opposed lower component is in fluid communication with ambient by way of an outlet aperture and throat leading through a lower wall portion of the oscillator chamber. The power nozzle is aligned with an axis of the oscillator chamber, while the opposed outlet aperture is offset from this axis a selected amount. Fluid under pressure enters the chamber though the power nozzle and circulates in the chamber, which in the illustrated embodiments is preferably generally spherical, to create a fluidic oscillation. Fluid from the oscillation chamber is ejected in variable-direction spray having a changing, or scanning cross-sectional pattern and with an outer conical shape, with the direction of the spray cone and its conical angle depending on the geometry of the outlet aperture and throat and by the amount by which the outlet aperture is offset from axis of the power nozzle.

This geometry and offset is preselected for each fluidic oscillator in a scanner sprayer so the cumulative effect of all the spray outlets produces a desired scanner spray pattern. Each spray cone may have a different geometry, or they may be all the same, or any combination may be used to produce the desired overall sprayer effect.

As an introduction to the present invention, attention is directed to the prior art configuration ofFIGS. 1-5, which illustrates a fluidic device that operates on a pressurized liquid flowing through it at a specified flow rate to generate an oscillating, cone-shaped spray of liquid droplets having desired properties. This device, which is described in commonly-owned U.S. Pat. No. 6,938,835 described above, the disclosure of which is hereby incorporated herein by reference, provides fluidic spray assemblies (i.e., fluidic oscillators with novel enclosures) that can provide specific types of desired sprays that had not been achievable with conventional fluidic technology, and more particularly demonstrates a 3-dimensional scanning nozzle. As shown inFIGS. 1 and 4, this fluidic device is a figure of revolution: a cylinder10with a domed-top endplate11. The top end plate11and bottom end plate12have round orifices or apertures d2and d1, respectively, which, preferably, are closely sharp edged or chamfered as shown at Cd1and Cd2. As shown inFIG. 4, in operation, liquid under pressure entering the bottom of the chamber generates an oscillating toroid T, which is smallest on the left side TLand largest on the right side TR, but this condition changes or alternates. The toroid flow pattern remains captive within the confines of the oscillation chamber, spinning about its cross-sectional axis and being supplied energy from the liquid jet entering from orifice d1.

The toroidal flow pattern (also shown inFIGS. 2 and 3) has diametrically opposed cross-sections which alternate in size to cause the fluid in the oscillation chamber to move in radial paths and also in tangential directions and thereby choose or traverse a different radial path at each sweep. As a result, there is a random-direction sweeping of the outlet jet issuing within a conical space facing away from the outlet orifice at the outlet area. As illustrated inFIG. 5, the randomly directed sweeping, or scanning single outlet jet quickly covers the area A, which is a cross-section of the conical spray taken in a plane transverse to the spray's central axis, in a substantially uniform, generally conical distribution with substantially uniform slugs or droplets of liquid. Thus, the scanning jet automatically and continually distributes the jet's effects (cleaning, for example) over an area, even if movement of a wand (not shown) in which the nozzle is mounted were halted. All of the outlets disclosed and illustrated in this patent promote recirculation on the side to which the jet is deflected, but the dome shape has the most unfavorable angle to promote recirculation on the opposite side, thereby allowing a larger deflection of the jet.

The use of fluidic circuits in sprayers such as shower heads is illustrated in prior artFIGS. 6A and 6B, taken from commonly owned U.S. Pat. No. 8,205,812 (Hester et al), the disclosure of which is incorporated herein by reference. Hester's '812 patent illustrates a fluidic device20that operates on a pressurized liquid flowing through it at a specified flow rate to generate an oscillating spray of liquid droplets having desired properties. Hester's '812 device provides multiple fluidic spray assemblies (i.e., fluidic oscillators with novel enclosures) indicated generally at22that can provide specific types of desired sprays. For example, as noted above, Hester's '812 device provides a spray that uniformly covers a relatively large surface area (e.g., a 400 cm2area at a distance of 30 cm from the spray head's exit) with liquid droplets that have large diameters (e.g., >2 mm), high velocities (e.g., > or about 4 m/sec) and pulsating frequencies that are in the range of perception by the human body (e.g., < or about 30-60 hertz). In accordance with Hester's '812 patent, a fluidic device that operates on a pressurized liquid flowing through it at a specified flow rate to generate an oscillating spray of liquid droplets into a surrounding gaseous environment and with the spray having desired properties (e.g., average spatial distribution, size, velocity, frequency and wavelength of liquid droplets at a defined distance in front of the device) includes a plurality of fluidic oscillators within the assemblies22, each having a channel that is part of a fluidic circuit for inducing oscillations in the pressurized liquid that flows through the oscillator so as to emit a liquid jet in the form of an oscillating spray of liquid droplets. The device includes a housing having an exterior surface that includes a rear face24and a front face26with a center-point28. An intermediate boundary surface30connects the faces. A plurality of passages29, each of which extends through the housing and intersects with the front and rear faces, are configured to allow for the insertion of one of the plurality of fluidic oscillators into each of the passages, so that the intersections of the passages with the housing front face define a plurality of outlets32. The geometrical arrangement of this housing's passages and their inserted oscillators is seen inFIG. 6Bto consist of an outer octagonal array of eight fluidic-oscillator-containing passages that is centered on the center-point of the front face. Inside this outer array is located an inner array of four fluidic-oscillator-containing passages that is also centered on the center-point of the enclosure's front face.

The geometrical arrangement of the Hester '812 outlets in the housing front face was chosen to achieve the desired properties of the oscillating spray when the device is operating at its specified flow rate. The fluidic oscillators chosen for this application were sized and proportioned so that, at the fluid pressures and flow rates at which they operated, they caused the liquid jets flowing from them to oscillate at a frequency of approximately 50 hertz and with the wavelength of approximately 10 cm. The result is a large area spray that, to the human touch, has very pleasing, vigorous (because of the relatively high velocity and large diameter of the droplets) massaging qualities. Furthermore, this spray is achieved at surprisingly low flow rates (i.e., ranges of 1.2-1.9 gpm versus non-fluidic, spray heads operating in the range of 2.0-2.5 gpm) as compared to those used by the currently available, non-fluidic, massaging spray heads which cover significantly smaller surface areas. In accordance with this prior art, maximum flexibility is provided in the design of showerhead oscillators with differing fan angles, oscillation frequencies, droplet sizes and velocities.

Hester's '812 showerhead (like traditional jet type shower heads) does not provide pleasing spray patterns, droplet size, droplet velocity, and temperature uniformity at very low flow rates (2 gpm or less) for showering. Furthermore, most prior fluidic showerheads have very few openings and so (as noted above) were hastily judged inferior by consumers who could spray the showerhead before purchase. In addition, prior fluidic showerheads were difficult to manufacture because of the difficulty in sealing the fluidic passages, and tend to be more expensive than conventional jet showers because of the number of component fluidics.

We reprise that prior art so that we can have a well-defined context for the scanner fluidic showerhead and method of the present invention as described below and illustrated in the accompanyingFIGS. 7-33A, to which reference is now made. The showerhead assembly and method of the present invention overcomes the problems (both perceived and real) of prior fluidic showerheads and provides an improved fluidic assembly that is also suitable for other spraying applications. In prior scanner fluidic showerheads, one scanner replaces 2-4 jets due to its small cone angle and uniform distribution. Thus, in a typical prior fluidic showerhead, one fluidic replaces 10-15 jets, leaving a typical prior fluidic showerhead with 4-10 openings, where a comparable jet type would have 40-100 openings, leading to the perception by potential consumers that fluidic showerheads had too few openings. The scanner fluidic showerhead as described and illustrated herein contains many more openings, and thus more fluidics, than prior devices. Thus, the fluidic spray output scanner throats provided in the devices of the present invention deliver uniform cone angles of about 8°. This is larger than a standard jet ˜2° cone, but smaller and more uniform than prior fluidics, ˜20°×5° for ‘2D’ and ˜35°×20° for ‘3D’ fluidic chips. A scanner fluidic showerhead in accordance with the invention can have from 5-40 openings, negating the perception by potential purchasers that they have too few spray openings. Further, the unique construction of the present device overcomes manufacturing difficulties of prior devices by making it very easy to seal its fluidic circuits, and in addition, it need not be as expensive as prior fluidic showerheads because there need not be as many components as were needed in such prior devices.

Turning now to a more detailed description of the present invention, reference is made toFIGS. 7-13, which illustrate at50a first embodiment of a fluidic scanning spray device which may be in the form of a hand-held body sprayer or shower, a fixedly or movably mounted showerhead, or the like, and which for convenience will be referred to herein as a scanner showerhead which incorporates a multiplicity of fluidic oscillators. The scanner showerhead50preferably is of a molded plastic material and includes a two-piece housing52having a rear (or top as viewed inFIG. 7) housing component54and a front plate (or bottom, as viewed in the Figure) housing component56mated at an interface58to form an enclosed plenum which encloses the fluidic oscillator elements of the invention, as will be described. As illustrated, the top housing component54incorporates a fluid inlet60for connection to a source of fluid under pressure, such as a conventional sprayer or shower supply fixture or hose (not shown), to which it is connected as by means of external threads as shown at62. The diameter of the interior64of the inlet is stepped down, as at a first inwardly extending shoulder66, a second inner shoulder68which is secured to an inner wall69formed by shoulder66, and a final inwardly extending shoulder70to form a small-diameter inlet71through which fluid flows, as indicated by arrows72, into the interior plenum74defined between the rear and front components, or portions,54and56of the housing52. In the illustrated embodiment, the inner shoulder68is in the form of a ring secured to wall69by, for example, three radial arms indicated at78, with the spaces79between the radial arms directing fluid flow indicated by arrows80into the plenum and cooperating with the central opening71to reduce turbulence in the fluid flow into the plenum74for even distribution of the flow to the outlet fluidic oscillators to be described.

The top housing portion54is generally cup-shaped, forming a housing cover portion having a top wall90, which incorporates the centrally-located inlet60, and a circumferential, downwardly-extending (as viewed inFIG. 7) side wall92having at its bottom an outwardly-flared circumferential sealing flange94which incorporates a flat bottom sealing surface96. As best seen inFIG. 8, the housing cover54incorporates around the sidewall92a plurality of outwardly-extending radial protrusions100spaced around the housing side wall. Each protrusion includes a through aperture102which is aligned with a corresponding aperture104in the bottom housing56for receiving a suitable fastener for assembly of the showerhead50. It will be noted that at the location of each outward protrusion100, the wall92of top housing component52incorporates a curved, inwardly-extending projection, or bulge110, as best seen inFIG. 9, which serves to provide sufficient thickness in the side wall92to accept the apertures102. The multiple protrusions and their corresponding inward projections produce a curved circumferential inner wall surface112, as seen inFIGS. 7 and 9.

The bottom, or front plate housing component56of the housing52includes a generally planar bottom wall120having a back (or top, as viewed inFIG. 7) surface122, a front surface124, and a circumferential wall126. As best seen inFIG. 8, the housing component56includes multiple circumferentially-spaced apertures104, with the back surface122incorporating a sinuous sealing groove130having inner and outer walls132and134and a groove bottom136for receiving a flexible circular seal (not shown). The inner wall132of the sealing groove follows the curvature of the curved inner wall112, so that when the housing52is assembled, upper and lower parts54and56of the housing engage at interface58with the surface96of the top housing54engaging the back surface122of bottom housing56and covering the sealing groove130to provide a fluid-tight seal between these upper and lower components when a suitable flexible seal is in the groove130. The scanner fluidic geometry contained in the housing, as will be described, does not require a large surface seal like prior fluidics so that the scanner fluidic of this invention can be molded in two parts that, when joined, provide a sealed housing using a very simple cylindrical seal that is much more robust than a large surface seal.

Molded as a part of the front plate housing component56are a plurality of concave depressions150, illustrated in perspective view inFIG. 8, which form the lower halves of fluidic oscillators for the sprayer50. For clarity, only one such depression will be described in detail, it being understood that all of them, in this case eight, are substantially alike and are formed during the molding process for making the component56. Each depression is molded to incorporate a cylindrical upper portion152, an inward ledge, or shoulder154, and a substantially hemispherical lower cavity portion156which will form a lower part of a two-piece scanner fluidic oscillator element when the scanner showerhead is assembled. At the bottom of the lower cavity portion, slightly offset radially outwardly from a centerline of the fluidic oscillator, and thus off center of the depression150, is an outlet aperture158which opens through a throat portion160formed in a wall portion162of the depression150. As best seen inFIG. 9, the throat portion160flares outwardly from the aperture158to produce a scanning fluid spray pattern, as will be described.

Mounted within each depression150, as illustrated inFIG. 7, is a corresponding cylindrical fluidic power nozzle insert170, which forms the second part of the two-part fluidic oscillator. The insert has an upper planar surface172and a cylindrical side wall174which has a diameter selected to fit snugly into the upper portion152of its corresponding depression. As illustrated in the cross-section ofFIG. 7, the bottom of each insert incorporates an open, downwardly facing substantially hemispherical dome176having a cylindrical bottom edge178which engages the ledge154in its corresponding depression when assembled. The inert dome and its corresponding depression form a spherical fluidic oscillator interaction chamber180. Centrally located in the upper surface of each cylindrical insert is an inlet passage182having an axis184, which is also the axis of the cylindrical insert170, and forming a power nozzle leading into the insert interior dome and thus into the interaction chamber180formed by each insert with its corresponding depression. As illustrated inFIG. 7, it will be noted that the outlet apertures158, and the throats160of each fluidic oscillator are offset radially from the axis184, and as illustrated, these offsets are of selected, usually different dimensions to provide predetermined different but complementary outlet spray patterns of each oscillator output scanner spray. In the illustrated embodiment, the outlets are spaced radially outwardly by different distances186and188in the two fluidic oscillators illustrated in cross-section inFIG. 7, but it will be understood that the offset may be in any direction from the axis184, the offsets may all be the same, or a selected mixture of offsets, or there may be no offsets, as selected for the desired scanner spray pattern. It is noted that the inserts may be partially serrated around their upper edges190for ease of handling.

The method of assembly of showerhead50involves positioning an insert170into each of the cylindrical upper portions152of depressions150in the front plate so that the bottom178of the insert engages the ledge154, with the inserts being secured in place by the tight fit of the insert outer side wall174, thereby forming a plurality, in this embodiment for purposes of illustration, eight fluidic oscillator interaction chambers and corresponding scanning spray outlets and outlet throats. A seal is placed in the groove130and the back and front portions54and56are positioned and aligned and are secured together by suitable fasteners, such as screws or bolts, to provide a fluid-tight enclosure. In operation, the shower head is secured to a suitable source of fluid under pressure, which flows into the interior plenum, or fluid manifold74of the housing, as indicated by arrows72and80. The fluid circulates in the chamber and flows at substantially equal flow rates into the several inlet power nozzles182, as illustrated by arrows190. The fluid enters the fluidic interaction chambers180under pressure, circulates in the chamber to produce a fluidic oscillation, and is ejected through the corresponding outlet aperture158and throat160to generate from each outlet a scanning fluidic spray output which is delivered in a uniform cone angle, illustrated inFIG. 7by arrows192. This scanning spray output is similar to that illustrated inFIG. 5, in that it randomly scans across and around the defined cone angle to produce a highly desirable flow pattern for use, for example in a shower.

The simplicity of the scanner geometry—an essentially spherical interaction region with opposed, but selectively offset, inlet (power nozzle) and outlet (throat)—allows for simplified construction of scanner fluidic arrays. As illustrated in the embodiment ofFIGS. 7-9and in the related second embodiment of the invention illustrated inFIGS. 10-15, such simplified construction is accomplished by molding the scanner throats and the downstream half of the interaction regions in one piece of the showerhead. In this scenario, as discussed above, the inserts containing the power nozzle and the upper, or upstream half of the interaction region are molded individually for each fluidic so that the component count for the fluidics device is equal to the number of fluidics plus one. This is more than in a prior fluidic shower, but the components are much simpler to design, mold, and assemble.

In the embodiment ofFIGS. 10-17, which are directed to a second embodiment198of the present scanner showerhead or sprayer invention,FIGS. 10-13diagrammatically illustrate a downstream, or front plate portion200of such a scanner spray utilizing multiple fluidic oscillator scanner sprays in accordance the present invention. In this illustration, front plate200is generally cup-shaped, having an upstanding cylindrical side wall202and a bottom wall204in which a desired number, in this case six, fluidic depressions206are formed. These depressions have corresponding outlet apertures208and scanner throats210, in the manner described above with respect to the depression150, outlet158and throat160ofFIG. 7.FIGS. 10-13illustrate the dimensions of a typical six-spray scanner shower head. In this embodiment, and as best seen inFIGS. 14 and 15, suitable inserts220are provided, having the shape described above with respect to inserts170inFIGS. 7-9, and being securable in the corresponding depressions206to form corresponding fluidic interaction chambers212, as illustrated diagrammatically inFIG. 16. In this embodiment, a rear, or upper housing portion230is configured to match and enclose the sidewall202of the front portion200of the assembly, and thus itself is generally cup-shaped, having a downwardly (or forwardly) facing cylindrical side wall which surrounds and engages the upper edge of the sidewall202, as best seen inFIG. 16, to provide a water-tight plenum234within the housing198. As with the embodiment ofFIGS. 7-9, the housing portion230has a rear wall240carrying a threaded fluid inlet fitting242, by which fluid under pressure is supplied to the interior plenum formed within showerhead198. As before, the inlet fluid circulates in the plenum234and flows through the insert power nozzles182, the fluidic interaction chambers212, and outlets208through throats210. As noted above with respect toFIGS. 7-9, the outlets208and throats210are selectively offset from the axes of their corresponding opposed inlet power nozzles182to produce the desired scanner spray pattern.

FIGS. 18 and 19illustrate exploded top and bottom perspective views of a third multiple fluidic oscillator scanner spray embodiment of the present invention, illustrating at250a fluidic oscillating scanner showerhead in accordance with the present invention. The showerhead incorporates a top (or rear) housing component252having an upper surface254in which is located an inlet fixture256that in this case is internally threaded, as at258, for connection to a suitable hose or pipe fitting to receive fluid under pressure. The inlet fixture is axially centered in the component252and passes through it to direct supplied fluid to an internal cavity, or plenum, formed within the showerhead assembly250. Spaced around the edge of the rear component252are a plurality of apertures for receiving suitable fasteners for securing this component to a corresponding bottom (or front panel) showerhead component270having a front face surface272around which are spaced apertures274corresponding to the apertures260in the top housing component252to receive corresponding fasteners for assembling the showerhead. In this embodiment, the showerhead includes, for example, five two-part fluidic oscillator circuits280for producing an output scanner spray, in accordance with the invention.

As illustrated in perspective views inFIGS. 18 and 19, and in cross-section inFIG. 20, a two-part fluidic oscillator280consists of upper and lower insert portions, or halves282and284which are separately fabricated, as by molding, and which fit together to produce a substantially spherical interaction region generally indicated at286inFIG. 20. The lower insert284includes a side wall290having a generally cylindrical exterior surface292which is stepped downwardly and inwardly to form a pair of steps294and296and a bottom wall300. The inner surface302of the insert portion284has an upper cylindrical portion304, an inwardly extending ledge306, and a substantially hemispherical, upwardly opening cavity308. In the bottom wall300of the insert portion284is an outlet aperture310which opens downwardly and outwardly from the cavity308through a tapered, expanding throat312.

The several lower insert portions284are received in corresponding openings or receptacles320in the front showerhead component, or front plate270, best seen inFIGS. 18 and 19. As illustrated, in this embodiment five receptacles are equally spaced around the front plate to receive five inserts, although it will be understood that they need not be equally spaced. On the rearward, or inner surface322of plate270it will be seen that the receptacles are spaced radially inwardly of a circumferential sealing groove324adapted to receive a suitable sealing gasket (not shown) for providing a fluid-tight seal when the showerhead250is assembled. Also, as seen inFIG. 18, and illustrated in the cross-section ofFIG. 20, each receptacle320has a cylindrical upper wall325and incorporates below that upper wall325inwardly extending steps, or ledges326and328shaped so that the receptacle receives the corresponding exterior wall292and steps294and296of the lower insert portion284, with each receptacle snugly securing a corresponding insert.

The upper portion282of the two-part fluidic oscillator280includes a top wall338and a depending sidewall340having a cylindrical outer surface342having an outer diameter which is snugly received in the upper cylindrical wall304of insert portion284upon assembly of the oscillator. The inner surface344of sidewall340forms a downwardly opening hemispherical dome346, the upper portion of which is formed in the top wall338of upper portion282of the two-part insert, as illustrated inFIG. 20. A fluid inlet aperture, or power nozzle350having an axis351extends through the top wall338to admit fluid under pressure into the substantially spherical interior interaction region286of the oscillator280. The spherical interaction chamber is formed when the upper insert portion282is joined to the lower insert portion284by pressing the two halves together so that the surface342is in contact with the surface304and the bottom352of portion282engages ledge306of portion284. To assist in the assembly of the device, the top surface354of each fluidic oscillator assembly280incorporates three spaced, upstanding spacer posts356(seeFIG. 18) which engage the undersurface360(seeFIG. 19) of the rear showerhead component252when the showerhead is assembled, to force the insert halves together and into their corresponding receptacles320.

When so assembled, fluid under pressure enters the showerhead250via inlet256into a plenum362formed between the top and bottom components252and270, and in which the upper portions of the fluidic oscillators are located. The fluid circulates in plenum362and flows between the upstanding spacer posts356into the power nozzle inlets350of each oscillator and into the spherical interaction region286. The spacer posts not only position the oscillators in the housing, but also act as turbulence filters to calm any turbulence in the plenum and to smooth the fluid flow into the fluidic oscillator power nozzles. The fluid flow into the spherical fluidic oscillator generates fluidic oscillations which, in turn, produce a fluid discharge from the region286through aperture310and throat312into ambient atmosphere to produce the conical scanner spray discussed above. As in the previously-described embodiments, the spray outputs from outlet apertures310and throats312are configured by selectively offsetting them from the axes351of their corresponding power nozzles in each of the fluidic oscillators to permit preselected scanner spray patterns for the spray device250.

FIGS. 21-25illustrate at400a fourth embodiment of the scanner sprayer of the present invention incorporating multiple fluidic oscillators wherein downstream (or front) halves of the oscillator interaction regions, including outlet apertures and throats, are all molded in one piece of the sprayer and upstream (or rear) halves of the oscillator including power nozzles and upstream halves of the interaction regions are molded in one other piece of the sprayer to simplify its manufacture and assembly. In this embodiment, the scanner sprayer400, which is illustrated as a showerhead having multiple spray outlet streams, includes a rear (or upper as viewed inFIGS. 21 and 22) cup-shaped housing member402having a top wall404and a forwardly (downwardly as viewed inFIGS. 21 and 22) extending, generally cylindrical side wall406having an inward peripheral shoulder407. Centrally located in the top wall402is an upstanding fluid inlet fixture408having a cylindrical side wall410carrying external threads412for receiving a suitable internally and externally threaded fluid supply fitting414. The fitting414may be any conventional supply fitting, with the illustrated device having a generally cylindrical wall420incorporating at its lower end422suitable internal threads424for engaging the threads412, and incorporating at its upper end426external threads428for receiving a threaded fluid supply hose or pipe, or the like (not shown). The fitting414may include an internal nozzle430secured at its lower end432in the upper wall portion426of fitting414and engaging a cylindrical seal433in the inlet fixture408, and having an upper connector portion434for receiving a supply fluid. The internal nozzle includes an outlet aperture436for directing fluid into an internal plenum440defined within the cup-shaped housing member402.

The undersurface450of wall404of the housing member402includes a plurality of spaced, arcuate reinforcing ridges452spaced inwardly from side wall406to provide reinforcement for wall404and to act as spacers for positioning a lower, or face plate portion454of the scanner sprayer400within the plenum region440. In addition, the ridges provide sufficient strength to receive a plurality of spaced fastener holes456. Corresponding fastener holes458are provided in the face plate454and may be threaded, as at460to receive a suitable fastener such as a threaded bolt for assembly of the scanner sprayer400.

The front plate454incorporates a three-tier, layered fluidic oscillator assembly forming multiple, two-part spaced fluidic oscillators to produce scanning sprays such as those described above in the previous embodiments. The front plate454includes a lowermost (as viewed inFIGS. 21 and 22) layer that is a supporting frontpiece470, which supports a middle layer plate472. The middle layer is molded to form the first parts of all of the oscillators, that is, the downstream (or front) halves474of the multiple fluidic oscillator interaction regions of this device. The middle layer in turn supports an uppermost layer, or top plate476that is molded to form the second parts of all of the oscillators, that is, the upstream (or back) halves478of the multiple fluidic oscillator interaction regions. Since these layers are each typically made by plastic injection molding methods, those knowledgeable with such manufacturing methods will understand that such manufacturing methods impose some constraints on the geometry of such inserts and their enclosures, so the described embodiment is illustrative of the invention. To facilitate the alignment of a large number of fluidic oscillators in the assembly454, one of the upper476or middle472layers may be molded out of a flexible material to allow it to conform to the other hard plastic layer. Alternatively, to facilitate the alignment of a large number of fluidic oscillators in the assembly and to allow bending of the fluidics into various aim angles, both the upper476and middle472layers may be molded out of a flexible material to allow them to conform to each other and the lower layer470may be a hard plastic forming a hard face or backing plate that holds prescribed aim angles.

As illustrated, the lowermost layer470has a front surface490which serves as the visible face of the sprayer (seeFIG. 25) and a substantially planar back surface491(seeFIG. 23) which is in contact with the middle layer472(seeFIGS. 21 and 22). Lower layer470incorporates a plurality of spray fluidics outlets492which are spaced around the scanner sprayer400in a desired pattern with the number of such outlets depending on the number of spray outputs desired for the scanner sprayer400. In the illustrated embodiment20such outputs are included, each substantially the same as those illustrated in cross-section inFIGS. 21 and 22. Each outlet492has a wall494that is tapered upwardly and outwardly, and is shaped to receive corresponding downstream fluidic oscillator components474formed by the middle layer472, with the wall including a shoulder496for positioning the downstream oscillator components, and a top surface aperture498into which the downstream oscillator components are inserted in the assembly of the front plate454. The lowermost layer also incorporates the fastener openings458described above.

Middle layer472is generally planar, having a bottom face500shaped to contact face491of the lowermost layer470, and having a top face502generally parallel to it. The middle layer incorporates a plurality of depressions, two of which are illustrated inFIGS. 21 and 22at510and512, with the number of depressions matching in number and location the number of front plate outlets492. Each depression has an inner surface514that is generally hemispherical and an outer surface516that is shaped to match the shape of its corresponding opening in the lowermost plate470and forms the downstream component474of a fluidic oscillator. A generally cylindrical upstanding wall520surrounds each depression and is positioned to receive and position the upper layer476.

The upper layer476of the front plate470is generally planar, with an upper surface522and a lower, generally parallel surface524, and incorporates a plurality of hemispherical domes530shaped by top curved walls531and downwardly extending side walls532and forming the upstream component478of a fluidic oscillator. The outer surfaces534of side walls532are generally cylindrical and fit into corresponding lowermost layer cylindrical walls520, when the front plate454is assembled, to produce generally spherical fluidic oscillator interaction regions, two of which are illustrated in the Figures at522and524. The top walls531incorporate centrally-located power nozzles540surrounded by upstanding cylindrical walls542and having upper ends544which open into the plenum440and lower ends546which open into the fluidic oscillator interaction regions, such as those illustrated at522and524.

Opposite the power nozzles540in each fluidic oscillator and located in the approximate center of the downstream hemispherical surface514is an outlet aperture550which opens into ambient by way of a downwardly and outwardly opening throat552which is shaped to produce desired fluid scanning spray characteristics. As in prior embodiments of the invention, the outlet apertures550are offset from the axes554(seeFIG. 22) of the corresponding power nozzles by selected amounts, again to produce desired fluidic oscillation in the interaction chambers and to produce desired spray scanning characteristics.

On the top surface of each power nozzle side wall542are spacer posts, such as posts560and562illustrated inFIGS. 21 and 22, which extend upwardly to engage the undersurface450of the upper housing component402when the device is assembled. If desired each oscillator may include three spaced posts, as illustrated in the embodiment ofFIG. 18. Between the posts are spaced openings564leading from the plenum to the power nozzle. These posts also serve as filters for the fluid in the plenum to reduce fluid turbulence in the inlets to the power nozzles.

Assembly of the scanner sprayer400is easily done. After the parts have been molded, the three layers of the front plate454are aligned (seeFIGS. 23 and 24) so that they may be pressed together with the depressions510,512of the middle layer472fitting snugly into the corresponding openings492in the bottom layer470, and with the downwardly-extending walls532of the upper layer476fitting snugly into the upwardly-extending walls520of the middle layer472. When pressed together, these three layers form the composite, or layered front plate454incorporating a plurality of fluidic oscillators having downstream, forwardly facing (downwardly in the views ofFIGS. 21 and 22) outlet apertures550. The front plate454is then inserted into the front-facing cavity formed by the cup-shaped rear (or upper) housing402and the entire assembly is pressed together and secured by fasteners through apertures456. Pressing the assembly together pulls the front plate inwardly into contact with the interior peripheral shoulder407of the side wall406of the upper housing402and the downwardly-extending ridges452so that the front plate and rear housing are spaced apart sufficiently to form the housing plenum440. Spacers452also engage the under surface450of the top housing component402to space the front plate from the top housing, with the spaces464between the spacers462providing fluid communication between the plenum and the oscillator power nozzles.

In operation, fluid under pressure, indicated by arrows570, is supplied to the sprayer400through inlet436and flows downwardly through inlet410into the plenum440and flows outwardly toward the fluidic oscillators. The fluid570enters the fluidic oscillators from the plenum by way of the spaces564between the spacer posts560,562and thus into the power nozzles540and the spherical interaction regions522and524, as best seen inFIG. 22. The fluid circulates in the interaction region to generate fluidic oscillations and is ejected through each outlet aperture550and throat552as a conical scanning spray580having a direction and conical angle as predetermined by the design of the individual fluidic oscillator.

As has been discussed above, for example in the description of the outlet apertures158and the throats160in the embodiment ofFIGS. 7-9, the apertures208and throat210in the embodiment ofFIGS. 10-17, the apertures310and throat312in the embodiment ofFIGS. 18-20, and the apertures550and552of the embodiment ofFIGS. 21-25, the outlet apertures of each fluidic oscillator are offset radially from the axes of the corresponding opposed power nozzles. These outlets are formed in the bottom surface of each fluidic oscillator, and with the exception of the embodiment ofFIGS. 18-20, are all molded in preselected locations and with preselected offsets in a single front plate incorporating multiple outlets. The configurations of these outlets, and the downstream throats, of selected, usually different, dimensions and angles to provide predetermined different but complementary outlet spray patterns for each oscillator output scanner spray. The offset of each fluidic oscillator may be in any direction from the corresponding power nozzle axis, and the offsets may all be the same, or a selected mixture of offset amounts, or there may be no offsets, as with each individual oscillator configured to produce a selected spray cone direction and angle, with all of them being selected to produce a desired overall, or composite, scanner spray pattern. The embodiment ofFIGS. 18-20differs in that the lower parts of the fluidic oscillator are each fabricated separately and are inserted in in a supporting faceplate270; however, as illustrated inFIG. 20, each may incorporate similar aperture and throat configurations having selected offsets from their corresponding power nozzle axes.

FIGS. 26-33Aillustrate in diagrammatic form a method for fabricating selected fluidic oscillator configurations that may be used with scanner sprayers of the present invention. For convenience, these illustrations are provided for the fluidic oscillator configuration of the embodiment ofFIGS. 18-20, but it will be apparent that the same configurations may be incorporated in the rest of the described embodiments. Further, these Figures include dimensions for a preferred embodiment of the invention, to better illustrate its features. Thus,FIG. 26is a diagrammatic cross-sectional view of a first version of a lower portion590of a fluidic oscillator insert that forms a lower half of a hemispherical chamber, or interaction region592, and which incorporates an outlet aperture594opening out of the interaction region592into an upper throat595and a lower throat596, in accordance with the present invention. This part590of the oscillator corresponds to the similar insert lower half284of the device ofFIGS. 18-20and thus includes an upstanding cylindrical wall597and a hemispherical wall598adapted to fit into, and be supported by, a front plate (not shown) such as the plate270illustrated inFIG. 20.

FIG. 27is a cross-sectional view of the insert590, taken along line27-27ofFIG. 26andFIG. 27Ais a top plan view of the device ofFIG. 27. As illustrated, the outlet aperture594opens into the upper throat portion595which tapers downwardly and inwardly from the interaction region through opening600, indicated by arrows602inFIG. 26, to define an upper throat length604. The upper throat opens through the downwardly and outwardly tapered throat portion596to ambient. The taper angle of the upper throat portion595is indicated by the angle lines606and608which are extensions of the wall of the upper throat and pass through the edges of opening600and aperture594on opposite sides of a central axis610. This axis passes through the centers of circular aperture594and circular opening600, and when inlet590is assembled in a sprayer such as that ofFIGS. 18-20, is also the axis of the oscillator power nozzle. In this version of the insert590, both the angle612between extension606and axis610and the angle614between extension608and axis610are selected to be 25°, and this equality of throat angles produces no offset of the outlet with respect to the central axis of the interaction region. These equal upper throat angles cause the insert590produce a first outlet spray pattern indicated by outlet spray arrows, this first output fluidic spray having a first selected, predetermined outlet axis and cone angle, in accordance with the invention.

FIG. 28is a diagrammatic cross-sectional view, also taken at lines27-27ofFIG. 26, of a second version630of a fluidic oscillator insert having an interaction region632defined by hemispherical wall633. A circular outlet aperture634leads to a downwardly and outwardly tapering upper throat portion636which opens through a circular throat opening638into a downwardly and outwardly opening lower throat portion640. In this version, the taper angles642and644of the upper throat portion differ on opposite sides of the central axis610(of the opposed power nozzle, not shown), as viewed inFIG. 27, with one half642of the throat having a wall angle of 31°, as illustrated by wall extension646, and the other half644having an angle of 19°, as indicated by wall extension648. The angle642of the throat wall at one side of the axis causes the base of the wall at opening638to shift closer to the axis, while the angle644of the wall at the other side shifts the opening away from the axis, thereby shifting, or offsetting, the opening638with respect to the axis and making the opening smaller, as illustrated inFIG. 28A. This configuration, in accordance with the present invention, effectively offsets the outlet throat from the axis610of the interaction chamber602to produce an outlet spray pattern, indicated by arrows650, having a second predetermined outlet axis and cone angle.FIG. 28Ais a top plan view of the device ofFIG. 28, and illustrates the throat offset.

Similarly,FIG. 29is a diagrammatic cross-sectional view taken at lines27-27ofFIG. 26, and illustrates a third version660of a fluidic oscillator chamber, or interaction region662formed by hemispherical wall664and having an outlet aperture666, and an inwardly upper tapered throat wall668leading to opening670. The upper part of the throat has a length672and is outwardly tapered at angle674, illustrated in the Figure on the left side of axis610by extension675at an angle of 37° and at an angle676, illustrated on the other side of the central axis by extension677at an angle of 13°. As explained with respect toFIG. 28, this angle difference shifts the opening670closer to the axis610with respect to the aperture666to produce a larger offset than that ofFIG. 28, as illustrated inFIG. 29A, and to make the opening670slightly smaller to produce an outlet fluidic spray indicated by arrows680having a third predetermined outlet axis and cone angle.

FIG. 30is a diagrammatic side elevation view of the device590ofFIG. 26, whileFIG. 31is a diagrammatic cross-sectional view taken along line27-27ofFIGS. 26 and 30, illustrating a fourth version700of a fluidic oscillator unit. This unit has an interaction region702defined by a hemispheric wall704having an outlet aperture706leading to an upper throat708having a lower opening709, configured as described above. As illustrated, the upper throat708has a wall that is inwardly tapered, as indicated by wall angle extensions710and712. One part of the throat wall, illustrated in the Figure on the left side of its axis610, is at an angle714of 43° and the other part, illustrated on the other side of the central axis, is at an angle716of 7°. This produces a larger offset of opening709at the bottom of throat708, with respect to the axis and to the aperture706than that ofFIG. 28, as illustratedFIG. 31A, which is a top plan view of the device ofFIG. 31. This configuration produces an outlet spray pattern having a fourth predetermined outlet axis and cone angle, as indicated by arrows720, in accordance with the present invention.

FIG. 32is a diagrammatic cross-sectional view, taken at27-27ofFIG. 26, of a fifth version730of an inset having a fluidic oscillator chamber, or interaction region732, and an outlet aperture734leading to an upper throat736configuration which has a lower opening737, in accordance with the present invention. The upper part of throat736has a wall that is downwardly and inwardly tapered, as indicated by wall angle extensions738and740, with one part of the wall, illustrated in the Figure by extension738on the left side of its axis610, at an angle742of 49°, and the other part, illustrated on the other (right) side of the central axis610at an angle744of 1°. This provides a larger offset of the opening737with respect to the axis610and the aperture734, and an opening that is smaller than those of the prior versions discussed above, as best seen inFIG. 32A, which is a top plan view of the device ofFIG. 32. This configuration produces an outlet spray pattern, illustrated by arrows748, having a fifth predetermined outlet axis and cone angle in accordance with the present invention.

FIG. 33is a diagrammatic cross-sectional view, taken at27-27ofFIG. 26, of a sixth version770of a sprayer insert including a fluidic oscillator chamber, or interaction region772defined by a hemispherical wall774. The interaction region incorporates an outlet aperture776which leads through an upper throat778to an outlet opening780, in accordance with the present invention. The upper throat778is downwardly and inwardly tapered, as indicated by wall angle extensions782and784, with one part of the wall, illustrated in the Figure by extension782on the left side of its axis610, at an angle786of 61°, and the other part, illustrated on the other (right) side of the central axis610at an angle788of 1°. This provides a larger offset of the opening780with respect to the axis610and the aperture776, and an opening that is smaller than those of the prior versions discussed above, as best seen inFIG. 33A, which is a top plan view of the device ofFIG. 33, to produce an outlet spray pattern790having a fifth predetermined outlet axis and cone angle in accordance with the present invention.

It will be noted that each of the described fluidic oscillator inserts described inFIGS. 26-33Aincorporates a protrusion800which serves as an alignment tab for aligning the insert with a support front plate in a sprayer. As indicated, the tabs are aligned with the direction of offset, and thus serve to identify the direction of the spray outlet for the corresponding insert.FIGS. 18 and 20illustrate the use of the inserts ofFIGS. 26-33Ain a sprayer device, where each of the lower halves of the inserts280incorporate an alignment tab800, while each opening320in the front plate270has an alignment notch802to receive a tab. The alignment notches are placed at predetermined locations around the circumferences of the openings320. Since each of the inserts590,630700730and770is configured to produce a different, known scanning spray characteristic; i.e. a known spray cone angle and direction as produced by the specific outlet offset, and since the locations of the notches are predetermined in the front plate, selection of any insert for any front plate opening allows provision of a desired combined spray pattern from the sprayer, which is a composite of all the selected individual spray inserts. Each of the inserts provides a scanning output within its cone, so that in accordance with the invention highly desirable scanning sprayers are provided

The variations in the outlet throat offset described inFIGS. 26-33Aillustrate the manner in which 3-dimensional scanning fluidic outputs, each providing a spray output that sweeps, or scans in a preselected, conical pattern size and direction, can be varied by changing the characteristics of the outlet throat angle and thus its location with respect to a fluidic oscillator interaction region axis which coincides with the axis of the opposed input power nozzle. These Figures illustrate typical measurements for fluidic oscillators in which vortices are produced to generate a scanning spray output having droplets of selected size and velocity, for use in scanner spray devices as disclosed herein to produce preselected spray patterns for scanning spray devices. In particular, the devices of the invention are used in applications such as scanner body sprays and showerheads to generate fluidic oscillator spray outputs which deliver a multiplicity of sprays having selected cone angles and directions. In the scanner fluidic showerhead assembly of the present invention, one fluidic scanner nozzle member effectively replaces 2-4 normal fluid jets by providing a small cone angle and uniform distribution, so that a scanner fluidic showerhead can have from 5-40 openings, which should overcome a possible objection (not enough openings) that may deter a consumer. In a typical prior fluidic showerhead, one fluidic replaces 10-15 jets, leaving a typical prior fluidic showerhead with 4-10 openings where a comparable jet type showerhead would have 40-100 openings.

Persons of skill in the art will appreciate that the present invention can be configured to provide a new scanner fluidic oscillator adapted or configurable for use in an economically manufactured fluidic showerhead or nozzle assembly (e.g.,50,198,250,400) which aims oscillating sprays from multiple scanner fluidics to spread water uniformly over a preselected coverage area positioned distally from or in front of the front plate or front panel (56,200,270,454). The scanner fluidics and showerhead of the present invention are configurable to provide a particular composite pleasing spray pattern with a selected, droplet size, droplet velocity, and temperature uniformity at very low flow rates (i.e., 2 gpm or less) for showering, washing or spraying a target area. The scanner fluidics are provided in a plurality of distinct configurations for generating individually tailored scanning sprays having a selected scanning spray characteristics. The showerhead's front plate (e.g.,56,200,270,454) is configured to support and aim the fluidic oscillators, optionally with indexing slots802configured to receive corresponding angular indexing tabs800on the fluidic oscillator inserts to orient and aim the spray from each fluidic oscillator (e.g.,172,220,282,530).

Having described preferred embodiments of a new and improved method, 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.