DE3072201T2 - FLUIDOSCILLATOR WITH INWARD-RESISTANT ELEMENT AND DYNAMIC FLEXIBILITY CIRCUIT. - Google Patents

Description

The present invention relates to improvements in fluid oscillators, and more particularly to a new fluid oscillator which can provide a dynamic output flow of a wide range of efficiency which can be obtained by simple design changes and which can further be quickly controlled by a suitable adjustment device during operation to achieve a comprehensive performance flexibility and thus enable a wide range of uses.

Fluid oscillators and their application as fluid circuit components are well known. Fluid oscillators that produce dynamic spray or flow patterns that are emitted into the environment have been used in the following ways: shower heads as described in USA 3,563,462; lawn sprinklers as described in USA 3,432,102; decorative fountains as described in USA 3,595,479; oral irrigators and other cleaning devices as described in USA 3,468,325; (see also USA 3,507,275 and 4,052,002 etc.). Most of these oscillators are manufactured to produce discharge patterns that are suitable only for use with the particular device for which they were designed and lack flexibility and adjustability for use in other applications. In most applications for state of the art oscillators, it has been found that performance is adversely affected by relatively small dimensional changes in the oscillator passages and the chamber. It has also been found that most state of the art oscillators require configurations or relatively large dimensions to meet certain performance requirements, so that practical size limitations exclude them from many applications. In addition, most prior art oscillators have not had the capability for extensive adjustment of the operating or performance characteristics to meet many applications requiring such adjustment capabilities.

Many prior art fluid devices, such as in US-A 3,016,066 and 3,266,508, have relied in operation on well-established fluid principles, such as the Coander effect. This reliance on well-known effects is the reason for the aforementioned limitations and disadvantages. A fluid device similar to that of US-A 3,016,066 is known from US-A 3,294,103, which has been considered in the preambles of independent claims 1 and 3.

It is an object of the present invention to provide a fluid oscillator which functions largely according to different principles than previous fluid oscillators and therefore overcomes the aforementioned limitations and disadvantages and creates possibilities which were previously not available in order to meet application requirements for which prior art fluid oscillators were not suitable.

It is a further object of the present invention to provide a fluid oscillator whose outflow pattern performance can be varied over wide ranges by simple design measures.

It is a further object of the present invention to provide a fluid oscillator that is relatively insensitive to dimensional manufacturing tolerances and dimensional variations resulting from its operation.

It is a further object of the present invention to provide a fluid oscillator with relatively small dimensions to meet practical size constraints of many applications. Where most prior art fluid oscillators require for satisfactory operation between the introduction of a feed fluid and the final outlet opening of at least 10 (but more often 12 to 20 and in some cases even 30) times the respective feed inlet nozzle width, the fluid oscillator of the present invention operates for example at relatively narrow widths as small as 5. Similarly, whereas most prior art fluid oscillators require relative widths for the overall channel structure of at least 7 or more, the structure of the oscillator of the present invention extends over a relative width of 5 or less in many applications. One can already appreciate the application advantages offered by such practical size reductions in the entire oscillator assembly area to about half or one third.

It is a further object of the present invention to provide a fluid oscillator which allows and enables adjustments in the performance characteristics over wide ranges during operation. An oscillator frequency and an angle of the output flow oscillation pattern and hence also such dependent characteristics as waveform, dispersion distribution, speed, etc. can be adjusted by a simple device so that the performance during of operation and can be adapted to changing requirements. Moreover, it is also an object of the present invention to provide a fluid oscillator whose performance with respect to the aforementioned characteristics can be adjusted or continuously modulated by externally applied fluid control flow pressure signals. By way of example, tests have been carried out on experimental models of fluid oscillators of the present invention which have demonstrated a frequency adjustment range of over an octave and an output oscillation angle adjustment range of from almost 0º to over 90º by applying an external fluid pressure flow to the oscillator control input connection with a control pressure in a range between a gauge of 0 (no control flow) and the same pressure as that supplied to the oscillator fluid power input. Additionally, inertance settings of the fluid inertance feedthrough of the oscillator have demonstrated practical continuous control during operation over a multi-octave oscillation frequency.

It is a further object of the present invention to provide arrangements of two or more similar fluid oscillators which can be precisely synchronized with each other in any desired phase relationship by means of suitable simple fluid feedthrough connections between such oscillators.

It is a further object of the present invention to provide fluid oscillators for use in shower heads to create a dispersion of the water flow into a suitable spray or massage setting and to provide improved cleaning effects due to the cyclically repeating flow impact forces on body surfaces, to further provide shower heads which include fluid oscillators for the aforementioned purposes, wherein an oscillation frequency and a spray angle are adjustable over wide ranges, and wherein the oscillators, when more than one is used, are synchronized with each other, and wherein manual controls are provided for such adjustments, and wherein the shower head includes manually adjustable valve means for selecting the mode for a conventional quiet spray or oscillator-generated spray and massage effects, or a combination thereof.

These objects are achieved according to the invention by a fluid oscillator as claimed in claim 1 or by a fluid spray device as claimed in claim 3. Advantageous embodiments are claimed in the dependent claims 2, 4 and 5.

The invention relates to a fluid oscillator for use in dispersing liquids, mixing gases and applying cyclically repeating impulse or pressure forces to various materials, material structures and to tissue surfaces of living bodies for therapeutic massage and cleaning purposes. The fluid oscillator consists of a chamber, a fluid inertia passage connected to the chamber at two locations, and a dynamic compliance downstream from that location. A fluid jet is discharged into the chamber from which the fluid exits through one or more small openings in the form of one or more discharge streams, the exit direction of which changes angularly from side to side in a cyclically repeating manner in accordance with the oscillation imposed on the flow within the chamber by the dynamic action of the flow itself.

The fluid inertance feedthrough connects two chamber locations on either side of the output jet and acts as a fluid transfer medium between those locations for a fluid diverted from the jet. The exit region of the chamber is shaped to permit formation of a strong vortex which provides dynamic compliance so that the jet as it passes through the chamber will tend to promote and introduce this strong vortex in a supportive manner in the absence of any effect from the inertance feedthrough and, after the fluid inertance of the feedthrough responds to the flow pattern influences contained in the chamber, the jet will tend to oppose this strong vortex, will slow it down and reverse its direction of rotation. The flow pattern contained in the chamber at any given time will consist of the jet exiting the chamber, expanding slightly and forming a strong vortex in its exit region. In view of the continuous outflow of a fluid from the periphery of the strong vortex through the small exit opening, the strong vortex would suck in a flow adjacent to the chamber wall on the side where the jet joins the strong vortex, and it would gladly abandon a flow near the opposite chamber wall. Until this fluid mass contained in the inertance passage connecting two sides of the chamber is accelerated by these effects of the strong vortex on the chamber flow pattern, a flow can neither be sucked in at one side nor abandoned at the other side, and the flow pattern maintains itself in this quasi-stationary state. Once the fluid in the inertance passage is sufficiently accelerated to feed the suction region and empty the discharge region, the flow pattern will feed the strong vortex intensified to the chamber exit region, and the strong vortex will dissipate. Even though now the reason for the acceleration of the fluid mass in the inertance passage has ceased to exist, this fluid mass continues continues to move due to its inertance, and it only decelerates gradually as its energy is dissipated in first dissipating and subsequently reversing the previous flow pattern state of the chamber to its symmetrically opposite state, at which time the fluid mass in the inertance passage will be accelerated in the opposite direction; after which the processes will continue cyclically and repeatedly in the manner described. An outlet opening from the exit region of the chamber outputs a fluid flow in an oscillation pattern determined at the outlet opening by the vectorial sum of a first vector tangential to the strong vortex of the exit region and a function of the rotational speed, and a second vector directed radially to the strong vortex and established by the static pressure in the chamber, together with the dynamic pressure component directed radially away from the strong vortex. By changing the average static pressure and rotational speed of the strong vortex and their respective relationship by suitable design measures, the angle subtended by the oscillating spray can be controlled over a wide range. By appropriately designing the oscillator, concentrations and distribution of fluid in the spray pattern can be quickly controlled. By changing the inertance of the fluid inertance pass, the oscillation frequency can be changed. By externally imposed pressure in the chamber exit region, the oscillation frequency and the pass angle can be quickly controlled. Two or more oscillators can be synchronized with each other in any desired phase relationship by means of suitable simple connections.

The above and other objects, features and advantages of the present invention will become apparent upon consideration of the following detailed Description of a particular embodiment thereof will become apparent, particularly in connection with the accompanying drawing pages:

Fig. 1 is an isometric view of a fluid oscillator constructed in accordance with the present invention as it might be viewed if the device were constructed of, for example, transparent material;

Fig. 2 is a top plan view of the bottom plate of another fluid oscillator according to the present invention;

Fig. 3 is a top plan view of the bottom plate of another fluid oscillator according to the present invention;

Fig. 4 is a top plan view of the bottom plate of another fluid oscillator of the present invention, diagrammatically illustrating the output waveform associated therewith;

Figures 5, 6, 7, 8 and 9 are diagrammatic representations showing successive states of current in a typical fluid oscillator of the present invention;

Fig. 10 is a top plan view of the outline of a fluid oscillator of the present invention with a diagrammatic representation of the waveforms of the discharge sprays emitted from a typical multiple outlet discharge portion of a fluid oscillator according to the present invention;

Fig. 11 is a top plan view of the outline of a fluid oscillator of the present invention, diagrammatically showing means for adjusting the length in the inertance feedthrough connection and indicating external connections for additional power adjustments and control in accordance with the present invention;

Figures 12 and 13 are diagrammatic view sections, from above and from the side, respectively, of an adjustment device for varying the inertance for use as the fluid inertance feedthrough, for example, the oscillators of Figures 1, 10, 11 or 14 in accordance with the present invention;

Fig. 14 is a diagrammatic representation of top plan views of a multiple fluid oscillator assembly synchronized by a link feedthrough device in accordance with the present invention;

Fig. 15 is an external perspective view of a typical shower head equipped with a power adjuster and a mode selector that reduce pressure and include two synchronized fluid oscillators in accordance with the present invention, and diagrammatically showing the associated output waveforms;

Fig. 16 is a diagrammatic front view illustration of a shower, spray booth or showerhead of a spray tunnel multiple spray head and a delivery plumbing fixture using the fluid oscillator of the present invention as spray heads or nozzles

Referring particularly to Figure 1 of the accompanying drawing pages, an oscillator 14 is shown as a number of channels and cavities etc. defined as recesses in a top plate 1, the recesses therein being sealed by a cover plate 2, and a piping or inertia feedthrough connection 4 between two bores 5 and 6 extending in the cavities through the top plate 1. It is to be understood that the channels and cavities formed as recesses in the plate 1 need not necessarily be two-dimensional, but may have different depths at different locations, with graded or stepwise changes in depth from one location to another. However, for ease of reference, entirely planar elements are shown here. It is also to be understood that where a two plate (i.e. plates 1 and 2) structure is shown on each of the embodiments, this is only to show one possible means of construction for the oscillator of the present invention. The invention itself resides in the various passages, channels, cavities, through-passages, etc., regardless of the type of structure in which they are formed. The oscillator 14, as formed by recesses in plate 1 and sealed by plate 2, includes an upstream chamber region 3 consisting generally of an approximately "U" shaped outline, with an inlet opening 15 located approximately in the middle of the base of the "U", the inlet opening 15 being the termination of the inlet channel 9 directed into the upstream chamber region 3. The open "U"-shaped upstream chamber region 3 extends outward to connect with the chamber exit region 11, which is again generally "U"-shaped, whereby the transition between the two chamber regions 3 and 11 is generally somewhat narrowed in width near chamber wall transition sections 12 and 13, so that the combination in this embodiment may give the appearance of what may be colloquially called an "hourglass shape". An outlet port 10 from the base of the "U" shaped chamber exit region 11 leads to the environment outside the structural housing of the oscillator. Short channels 16a and 16b lead in a generally upstream flow direction from the upstream chamber region 3 on either side of the inlet port 15 (from near corner regions 8 and 7) to bores 6 and 5 respectively.

The operation of the oscillator 14 is best illustrated in Figures 5 through 9. For purposes of description herein, it is assumed that the working fluid is a liquid and that the liquid is discharged into an air environment; however, it is to be noted that the oscillator of the present invention operates equally well with gaseous working fluids and that any working fluid may be discharged into the same or any other fluid environment. Upon receipt of a pressurized fluid through the inlet port 15, a jet of fluid is discharged and flows through the upstream chamber region 3 and the chamber exit region 11 and exits through the exit port 10 as shown in Figure 5. However, as a result of the expansion of the fluid jet during its passage through the chamber regions 3 and 11 and some loss of cohesion of the jet due to shear effects, some portions of its flow are pared off before exiting through the orifice 10 and such portions of the flow rapidly fill voids in the chamber cavities and also fill the inertia connection 4 as further shown in Fig. 5. Asymmetries inherent in structure and asymmetries inherent in the portions of pared off flow on either side of the jet ensure that complete filling occurs, for all practical purposes and almost instantaneously. The same The aforementioned inherent asymmetries will cause more of the flow to be peeled back on one side of the jet than on the other side, which will necessarily cause the jet to transition into a high swirl flow pattern resulting in the pattern shown in the chamber exit region 11 of Figure 6 (or its symmetrically opposite pattern). The tendency of the jet to transition into the high swirl pattern in Figure 6 is aided and amplified by the increasingly larger amount of flow peeled back due to the more angled approach of the jet to the outlet opening 10. Opposite this tendency is the jet flow momentum which acts to straighten the jet. A mutual balance of these influences on the jet is necessarily achieved before the jet can deviate completely to the respective side of the chamber exit region 11. By the inherent nature of this flow pattern, a powerful suction region builds up approximately in the vicinity itself where the jet flow enters the strong vortex near the transition between chamber regions 3 and 11 on opposite sides of the jet, towards the center of the strong vortex, and the strong vortex would like to abandon flow on its sides of the jet. The only path that can allow an exchange of flow between this suction region and the return region or abandonment region is along both sides of the jet in an upstream direction through the sides of the upstream chamber region 3 and across the inertance feedthrough junction 4. However, since the inertance feedthrough junction 4 presents a significant inertance and thus an impedance to flow changes due to its physical design, the fluid mass contained in this feedthrough junction 4 and in the remainder of this path between the suction and return regions must be accelerated before flow between these two regions can be allowed to pass. described flow pattern in quasi-steady state shown in Fig. As soon as the flow in the inertance feedthrough junction 4 is accelerated to a sufficient extent to feed the suction region and empty the return region, the previously established flow pattern will gradually cease to feed the strong vortex in the chamber outlet region and the strong vortex will disperse as shown in Fig. 7. Even if now the reason for the acceleration of the fluid mass in the inertance feedthrough junction has ceased to exist, the fluid mass continues to move due to its inertance and it is only gradually decelerated as its dynamic energy is consumed first in dispersing and later in gradually reversing the previous flow pattern state in the chamber to its symmetrically opposite state as shown in Figs. 8 and 9, after which this fluid mass in the inertance feedthrough junction will start to be accelerated in the opposite direction; thereafter, the sequence of events continues cyclically and repeatedly in the manner described. The sequence of events shown in Figs. 6, 7, 8 and 9 (in that order), and as described above, represents flow pattern states and their changes at different times within a half cycle of oscillation. To visualize the events of the second half cycle of oscillation, one need only symmetrically reverse all the flow patterns shown, beginning with the one shown in Fig. 6 and continuing through Figs. 7, 8 and 9.

It should perhaps be mentioned here that while the inertance effect of the inertance feedthrough 4 is clearly analogous to an electrical inductance (L), the effect of a reversing strong vortex in a confined flux pattern, when occurring in the oscillator of the present invention, can be considered to produce a dynamic compliance (even when operating with incompressible fluids), and it provides an analogous effect not unlike that of an electrical capacitance C. From the preceding description, one can quickly imagine the alternating energy exchange between the inertance of the fluid in the inertance feedthrough junction and the dynamic compliance of the highly vortex flow pattern as analogous to the mechanism of a resonant electrical inductance/capacitance (LC) oscillator circuit.

As a result of the aforementioned changing flow pattern with strong vortex in the chamber exit region 11, flow through the exit port 10 enters a side-to-side oscillating pattern which is determined at the exit port by the vectorial sum of a first vector tangential to the strong vortex of the exit region and a function of rotational speed, and a second vector directed radially away from the strong vortex and established by the static pressure in the chamber exit region 11, together with the dynamic pressure component directed radially from the vortex at the exit port 10. A resulting typical exit flow pattern 16 is shown diagrammatically in Fig. 4. It can be seen in Fig. 4 that this exit flow pattern 16 takes on a sinusoidal shape with the wave amplitude increasing with distance downstream. Since the pattern 16 shown represents the state at a moment, one must clarify the current dynamic situation; the wave of the pattern 16 migrates away from the exit opening 10 when it expands in its amplitude, which spans the angle α;.

Referring to Fig. 2, the oscillator 17 shown is shown with only the plate 18 in which the recesses containing the oscillator channels form and contain the cavities, and the cover plate is removed for simplicity and clarity of description. In fact, most of the oscillators shown and described hereinafter have the cover plate removed for these reasons. The oscillator 17 includes an inlet port 19 similar to the inlet port 15 of Fig. 1, and an inertance feedthrough 20 similar to the inertance feedthrough connection 4 of Fig. 1, except that the latter is in the form of a tube connection external to the top plate 1 of the oscillator of Fig. 1, and the former is in the form of a channel connection formed in the plate 18 of Fig. 2 itself. An inlet passage and hole 21 corresponds to the inlet channel 9 of Fig. 1. An upstream chamber region 22a and a chamber exit region 22b correspond to the upstream chamber region 3 and the chamber exit region 11 in Fig. 1, respectively, except that the chamber wall transition sections 23 and 24, corresponding to sections 12 and 13 of Fig. 1, are curved inwardly in a downstream direction until they meet strongly inwardly directed wall sections 25 and 26 leading to the exit opening 10 (the same as the exit opening 10 in Fig. 1). The chamber exit region 22b, although of slightly different shape from the corresponding region 11 of Fig. 1, serves the same purpose as previously described. While the narrowed transition between regions 3 and 11 of Fig. 1 provides certain performance characteristics under certain specific operating conditions, the inwardly curved wall transition of wall sections 23 and 24 of Fig. 2 provides other performance characteristics under different operating conditions without changing the basic function of the oscillator already described with reference to Fig. 1. For example, chamber regions 22 and 23 cause the discharge spray pattern (among other features) to be smaller droplets than the hourglass shape of the corresponding areas of Fig. 1. An inertance feedthrough 20 located in the plate 18 does not cause any different oscillation than the inertance feedthrough 4 of Fig. 1, except insofar as a different inertance results due to different physical dimensions. Basically, inertance is a function of the fluid density contained and is proportional to the length of the feedthrough and inversely proportional to its cross-sectional area. Consequently, longer feedthroughs and/or feedthroughs with smaller cross-sectional areas produce greater inertances and thus cause lower oscillation frequencies of the oscillator.

In Fig. 3, an oscillator 27 is again shown with only the plate 28 in which the recesses forming the oscillator channels and cavities are contained, so shown for the same reason as already described with reference to Fig. 2. The oscillator 27 of Fig. 3 has the same general configuration form as shown for the oscillator 17 of Fig. 2, except that the inertance feedthrough 29 assumes a circular path, and regions 30 and 31 define a smoother wall contour which is even more inwardly curved and begins its curvature near the two ends of the inertance feedthrough 29. As discussed with reference to FIG. 2, different designs of the inertance feedthroughs have an impact on the basic oscillator operation, but flexibility in design provides different advantages in designing and constructing actual products incorporating the oscillator of the present invention, and it is a particular purpose of FIGS. 1, 2, 3 and 4 to demonstrate such flexibility. The oscillator 27 of FIG. 3, in view of its discussed more inwardly curved smoothed chamber wall outline, may have certain different performance characteristics, such as narrower spray output angles, a more cohesive output flow with larger droplets in a narrower size distribution range, etc. The basic function and operation of the oscillator 27 is the same as already described with reference to the oscillator 14 of Fig. 1.

Referring particularly to Fig. 4, there is shown an oscillator 32 with only the plate 33 in which the recesses forming the oscillator channels and cavities are contained, which is shown as such, for the same reason as already described with reference to Fig. 2. The oscillator 32 has the same general construction and shape as shown for the oscillator 14 of Fig. 1, except that the inertance feedthrough 34 is shaped similarly to the inertance feedthrough 29 of Fig. 3, and that it is also contained as a recess in the plate 33, corresponding to the construction shown in Fig. 3, and that the inertance feedthrough 34 is formed into a very short path, the effect of which is to increase the oscillation frequency, for reasons already discussed with reference to Fig. 2. A chamber region 35 is simply adjusted in width near the inlet opening 19 to match its walls with the outer wall of the ends of the inertia feedthrough 34, which has no relation to the general function and operation of the oscillator 32, as distinguished from the oscillators 14, 17 and 27 (Figs. 1, 2 and 3 respectively). The chamber exit region 36 corresponds to the chamber exit region 11 of Fig. 1 in construction and function. Compared to, for example, the construction of the oscillator 27 of Fig. 3, the chamber shape, particularly the wider and generally larger exit region 36 of Fig. 4, will give rise to different performance characteristics; for example, wider spray discharge angles α, a more cohesive discharge flow with a narrower droplet size distribution, smoother output waveforms of more sinusoidal character, etc. A typical output waveform generally applicable to all oscillators of the present invention is shown diagrammatically as output flow pattern 16 of Fig. 4. The basic function and operation of the oscillator 32 of Fig. 4 is the same as that already described with reference to the oscillator 14 of Fig. 1.

It should be noted that with respect to the effects of relatively sharp changes in the inertances of the inertance feedthroughs, in particular width and length dimensions of the chamber exit areas, certain performance trends have been experimentally verified, as shown below: very high relative inertances cause output waveforms to take on more and more trapezoidal characteristics. Gradually reduced relative inertances cause output waveforms to converge and possibly achieve a sinusoidal character, and further relative reductions in inertance cause a sharpening of the wave peaks, causing waveforms to possibly achieve triangular shapes. Additional relative inertance reductions result in small additional waveform changes, if any, but they cause gradual swing or angle reductions (which actually remain constant to inertance changes up to that point). Of course, oscillation frequencies changed during these experiments in accordance with the different relationship between applicable oscillator characteristic parameters and applied inertances.

Design control over output waveforms is an important aspect of the present invention, since the output waveform is largely based on the spray flow distribution or droplet density distribution across the output spray angle, and different requirements pertain to different products and applications. For example, trapezoidal waveforms generally provide higher densities at extremes of the swing angle than anywhere else. Sinusoidal waveforms provide even more uneven distributions with higher densities at extremes of the swing angle and usually reduce densities near the center. Triangular waveforms generally provide a uniform distribution across the swing angle.

Referring to Fig. 10, an oscillator of the general type shown in Fig. 1 is modified by replacing one output port 10 of Fig. 1 with three output ports 37, 38 and 39 located in the same general area. In fact, any number of output ports may be provided along the front (output) vicinity of the chamber exit areas at any desired distances and of the same or different sizes. The output ports 37, 38 and 39 in Fig. 10 will each output an output flux pattern exhibiting the same characteristics as described in detail with respect to Figs. 1 or 4. The oscillation angles of the multiple output flux patterns may be separate, or they may overlap as required by performance requirements. Waveforms will be of generally identical phase relationship (and frequency). An inertance feedthrough connection 40 is shown for directly connecting regions 41 and 42 without using intermediate channels such as those shown in Fig. 1 as short channels 16a and 16b. The variation is shown only to show another design option that is possible if the size and other design criteria allow or impose such differences, and it has no effect on the basic function and operation of the oscillator shown in Fig. 10, which is the same as that already described with reference to the oscillator 14 of Fig. 1. The purpose for multiple discharge orifices in oscillators as shown in Fig. 10 is to be able to obtain different discharge spray characteristics; e.g., different distributions, spray angles, small droplet sizes, low spray burst forces, several widespread spray discharge patterns, etc.

Referring to Fig. 11, an oscillator of the general type shown in Fig. 1 is modified by providing an opening 43 in the chamber exit region 44, using an inlet hole 47 as in the inlet opening 19 and the inlet through hole 21 both in Fig. 2, and using an adjustable length inertia feedthrough connection 45. Fig. 11 shows further fluid supply connections to the inlet hole 47 and also to the opening 43, both leading from a valve means 46 shown in block form. The oscillator of the arrangement in Fig. 11, which operates in the same manner as the oscillator 14 of Fig. 1, in receiving pressurized fluid through the opening 47, is not affected by the presence of the opening 43 so long as feeding to the opening 43 is excluded, and it is not affected by the presence of the adjustable length inertia feedthrough connection 45, except to the extent that the oscillation frequency will change as a function of a change in the length of the connection 45. The oscillation frequency can be further varied by adjusting the valve means 46 as pressurized fluid enters through the opening 43 in the region 44. Such entry of fluid occurs at relatively low flow rates and does not generally affect the basic flow pattern operations in the region 44. As the pressure on the opening 43 is increased, however, the static pressure will prevail in region 44, and also in the rest of the oscillator. This has two main effects: firstly, the supply flow through orifice 47 will be reduced due to the increase in the back pressure experienced, and consequently the oscillation frequency will be reduced as the jet velocity also reduces; and secondly, the static pressure in region 44 in particular will increase. A change in the vector sum at the oscillator output orifice from the various velocities described in detail with respect to the operation of the oscillator embodiment shown in Figure 1 such that the second vector directed radially to the strong vortex increases with respect to the first vector tangential to the strong vortex of the exit region, and consequently the output flow oscillation angle decreases. Thus, it can be seen that adjusting the pressure supplied to orifice 43 changes the oscillation frequency and the output flow oscillation angle. At the same time, only minimal total flow rate changes will be experienced by the oscillator because the pressurization of the region 44 via the orifice 43 and the inflow of additional fluid thereby caused through the orifice 43 is compensated to some extent by the accompanying decrease in supply flow through the inlet hole 47. Pressure adjustment by means of a valve means 46 may be applied exclusively to the orifice 43 while maintaining a pressure at the inlet hole 47 constant, or both pressure supplies may be adjusted independently, or both pressures may be adjusted by valve arrangements joined together in some conventional relationship. Furthermore, the pressure (and flow) input to the orifice 43 may be from any fluid source, for example one which will provide a pressure change dependent on a time or event, such as for example controlling or modulating the oscillator input as a function thereof. Experimental results have shown practical frequency adjustment ranges of over an octave and output oscillation angle adjustment ranges of almost 0º to over 90º without exceeding the supply pressure to the inlet hole 47 by the adjustment pressure to the port 43. In addition to the power adjustments offered by the aforesaid arrangement, the oscillation frequency is independently adjustable by means of a length adjustment of the adjustable length inertia feedthrough connection 45, which is simply an arrangement similar to the slide of a trombone, whereby the length of the feedthrough can be continuously varied. Experiments have shown practical adjustment ranges of up to several octaves using such an arrangement. It is possible to provide valve assemblies which are combined not only to adjust the pressure to the orifice 43 and to the inlet hole 47, but also mechanically coupled to adjust the length of the inertance feedthrough connection 45 with a single control means so that, for example, a single manually rotatable knob causes oscillator output power variation over a further extended very wide range. The aforementioned power adjustment capabilities will be particularly useful in applications where operating requirements vary. In other applications, adjustability is required to adapt the power to subjective requirements; for example, oscillators used in massage shower heads for therapeutic or simply recreational purposes would show particularly advantageous appeal if their effects could be adjusted to a wide range of individual subjective needs and desires.

Referring to Figs. 12 and 13, there is shown a compact adjustment device for varying the inertance of the inertance feedthrough connection of any of the oscillators shown in Figs. 1-11 and 14. A cylindrical piston 47a is axially movably disposed within a cylindrical hollow body 48, the piston 47a being circumferentially sealed by a seal 49. A portion of the body 48 is of slightly larger inner diameter than the piston 47a so that an annular cylindrical void 48a is formed between the piston 47a and the body 48 when the piston 47a is moved fully into the body 48, and so that a partially annular and partially cylindrical void is formed when the piston 47a is in a partially retracted position, and so that a cylindrical void is formed when the piston 47a is further retracted. The inner peripheral wall of the cylindrical hollow body 48 has two feedthrough connections aligned close to each other and approximately tangential to the inner cylindrical circumference, with the feedthrough inlets pointing away from each other. The feedthroughs lead to connecting ports 50 and 51 respectively. Since the inertance between the two ports 50 and 51 is a proportional function of the length and an inversely proportional function of the cross-sectional area of the path, if passing between the ports 50 and 51 the device shown in Figs. 12 and 13 were compelled to take it, it can be shown that the inertance of this path is continuously varied as the piston 47a is moved within the body 48 and as the internal void changes shape and volume between one extremum of a cylindrical ring when a higher inertance is obtained and the other extremum of a cylinder when the lowest inertance is reached. Compared to the variable inertance feedthrough connection 45 of Fig. 11, the arrangement of Figs. 12 and 13 offers compactness, easy sealing and a less critical structure. If the slider of the connection 45 of Fig. 11 is replaced by the arrangement of Figs. 12 and 13 by connecting the terminals 50 and 51 respectively to the two bushing legs opened by the removal of the connection 45, the entire operation and adjustment described with reference to Fig. 11 is valid.

Referring to Fig. 14, two oscillators of the general type shown in Fig. 1 are connected by suitable synchronizing feedthroughs 52 and 53 between symmetrically positioned locations of respective inertance feedthrough connections, particularly between such locations near the chamber inlets 54, 55, 56 and 57 of the inertance feedthrough connections. Feedthrough 52 connects inlet 54 to inlet 57 and feedthrough 53 connects inlet 55 to inlet 56. The two oscillators will oscillate synchronously in the connection shown provided they are both similarly constructed to operate at nearly the same frequencies when supplied with the same pressure and their relative phase relationship will be 180° when viewed as drawn. Swapping the connections of the two entries on just one oscillator, for example reconnecting feedthrough 52 to entry 55 and feedthrough 53 to entry 54, will produce an in-phase relationship. Different lengths and unequal lengths of feedthroughs 52 and 53 and also changes in the connection locations of the synchronizing feedthroughs along the inertance feedthrough connections will result in a variety of different phase relationships. It is also possible to connect dissimilar oscillators in this way to create a lock-in at harmonic frequencies. More than two oscillators can be connected together and synchronized in the same way, and such arrangements may be connected to produce different phase relationships between different oscillators. Furthermore, series connections between many oscillators may be used, synchronizing feedthroughs may be used to produce the inertance previously supplied by the inertance feedthrough connections, and individual oscillator inertance feedthrough connections may be omitted.

Referring to Fig. 15, there is shown a typical portable massage showerhead which includes two synchronized oscillators of the general type shown in Fig. 1 connected by an arrangement as shown in Fig. 14 and equipped with variable power adjustment arrangements generally described with reference to Fig. 11 and Figs. 12 and 13. The showerhead is supplied with water under pressure through a hose 58 and generally includes valve means for mode selection between conventional stationary spraying and a massage action. Manual controls 59 and 60 are arranged to advantageously provide not only mode selection control but also the adjustment control for the frequency and the oscillation angle (as described with respect to Fig. 11 by means of the pressure adjustment to the opening 43 and/or by a combined or combined pressure adjustment to the feed hole 47), all of the foregoing adjustment controls and the mode selection preferably being arranged in one of the two hand controls 59 or 60, and to provide the independent frequency adjustment (as described with respect to Figs. 11, 12 and 13 by means of the inertance adjustment of the inertance feedthrough connection 45 or by means of the arrangement shown in Figs. 12 and 13) in the other of the two hand controls 59. or 60. The measured or combined mode selection and frequency and oscillation angle control may be a valve arrangement which allows feed water passage only to the conventional stationary spray nozzles when the manual control is in an extreme position. When the manual control is rotated by a certain angle, the valve arrangement allows feed water passage also to the feed inlets of the oscillators, and with a further control rotation, water passage is allowed only to the feed inlets of the oscillators. A further additional rotation of the manual control will reduce the frequency and oscillation angle by adjusting the respective pressures of the oscillators.

The independent frequency adjustment is a mechanical arrangement that allows the required translational movement to the respective inertance feedthrough connection setting described in detail above. Thus, for example, the respective manual control 59 or 60 can be adjusted by rotation between two extreme positions while the oscillation frequency changes between corresponding values. It should be noted here that the frequency settings have such a relationship with respect to each other that the frequency range ratio of one is approximately multiplied by the frequency range ratio of the other to obtain the total combined frequency range, which is therefore greatly expanded due to the two control settings.

In Fig. 16 an application of the oscillator of the present invention is shown in a shower or a spray booth (or shower or spray tunnel), wherein a plurality of oscillators in the form of identical nozzles 61 are arranged and mounted at different locations along a liquid supply passage 62, the liquid under pressure to each nozzle 61. The feedthrough 62 is formed along its length into a door outline or any suitable shape for the particular application. The nozzles 61 are directed inwardly to produce an overlap of spray patterns. The nozzles 61 are preferably aligned with the plane of their spray patterns in the plane determined by the shape of the feedthrough 62. The purpose of such an arrangement is to produce a large spray area coverage with minimal flow consumption, for example in shower cubicles or in spray booths, where one or more such arrangements may be installed. The oscillator nozzles of the present invention are not only capable of producing the large area coverage with relatively fine spray at minimal flow consumption, but they offer additional advantages in the arrangements shown in Figure 16 in that they are much less subject to clogging than conventionally used stationary stream or spray nozzles due to the small openings of the latter in relation to the much larger oscillator channels. Furthermore, orders of magnitude greater numbers of conventional nozzles are required to achieve the same effect than the wide angle spray nozzles required to produce the same coverage.

Claims (5)

1. A fluid oscillator (14) having a chamber (3,11), an inlet port (15) for discharging a jet of working fluid into the chamber (3,11) and an outlet port for discharging working fluid from the chamber (3,11) to the environment, a fluid inertia flow passage (4) transferring the working fluid between a first and a second location (7,16b 5; 8,16a,6) on opposite sides of the jet and near the inlet port (15) in the chamber (3,11), characterized by a dynamic compliance in the form of a region of strong vortex defined between side walls of the chamber (3,11) which converges generally towards the outlet port (10) and near the outlet port (10) so that the working fluid in the jet in the strong vortex region forms a strong vortex flowing alternately in opposite directions, the strong vortex alternately sucking fluid from the first and second locations (7, 16b, 5; 8, 16a, 6) and supplying fluid to them in opposite phase, and thereby through the inertance flow passage (4) in alternating opposite directions. 2. Oscillator according to claim 1, further comprising means for changing the inertance of the flow passage (45). 3. A fluid spray device comprising: a chamber (3, 11), a fluid inertia flow device (4), an inlet device (15) for discharging a jet of a working fluid into the chamber (3, 11), outlet means (10) for discharging a working fluid from the chamber (3, 11) in a flow pattern and direction determined by the static pressure and flow velocity of the working fluid in the chamber (3, 11), characterized by dynamic compliance means in the form of side walls (3, 11) converging against and near the outlet means (10) for establishing a high vortex flow of the working fluid discharged into the chamber (3, 11), the high vortex fluid inertia flow means cyclically reversing between a first and a second flow direction, the fluid inertia flow means having first and second locations (7, 16b, 5; 8, 16a, 6) in the chamber (3, 11) on opposite sides of the jet in the vicinity of the inlet means (15) so that a strong vortex flow in the first flow direction draws fluid from the fluid inertance means (4) at the first location (7, 16b, 5) and carries fluid into the fluid inertance flow means (4) at the second location (8, 16a, 6), and so that the strong vortex flow in the second direction draws fluid from the fluid inertance flow means (4) at the second location (8, 16a, 6) and carries fluid into the fluid inertance flow means (4) at the first location (7, 16b, 5), the fluid inertance flow means (4) including means for establishing flow inertia for delaying changes in flow conditions through the fluid inertance flow means (4) in response to differential pressure changes across the first and the second place (7, 16b, 5, and 8, 16a, 6). 4. A spray device according to claim 3, comprising a frequency control device (45) for allowing selective control of the frequency at which the flow with high vortex directions are reversed. 5. Spray device according to claim 4, wherein the fluid inertia flow means (4) comprises a small cross-sectional flow passage extending between the first and second locations, and wherein the frequency control means (45) comprises means for selectively adjusting the length of the flow passage.