Abstract:
There is disclosed a fluidic spa tub nozzle having a fluidic oscillator with diverging sidewalls and a cooperating mode-change member for changing the mode from an oscillatory swept jet mode to a straight jet mode and positions thereinbetween. The fluidic oscillator has an inertance loop formed by groove plates secured to the top and bottom walls of the fluidic oscillator.

Description:
REFERENCE TO RELATED APPLICATIONS 
   This application is related to provisional application Ser. No. 60/331,131 filed Nov. 9, 2001 entitled FLUIDIC SPA NOZZLE WITH MODE CHANGE DISC. 

   BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION 
   Fluidic and spa nozzles are widely known in the art. See for example the following patents: 
   
     
       
             
             
           
         
             
                 
             
             
               U.S. Pat. Nos. 
               Inventor 
             
             
                 
             
           
           
             
               3,471,091 
               Baker 
             
             
               4,151,955 
               Stouffer 
             
             
               4,227,550 
               Bauer 
             
             
               4,325,235 
               Bauer et al 
             
             
               4,407,032 
               Bauer et al 
             
             
               4,416,030 
               Reynoso 
             
             
               4,800,046 
               Malek et al 
             
             
               4,982,459 
               Henkin 
             
             
               4,985,943 
               Tobias et al 
             
             
               5,095,558 
               Howard 
             
             
               5,269,029 
               Spears et al 
             
             
               5,495,627 
               Leaverton 
             
             
               5,810,257 
               Ton 
             
             
               6,378,146 
               Johnston 
             
             
               6,401,273 
               Fung et al 
             
             
                 
             
           
        
       
     
   
   The present invention incorporates fluidic oscillators adaptable for submerged operation, e.g. for spa use, which can be caused to sweep or not sweep a jet of water with simple manual adjustment from the front of the device. In addition, the frequency of oscillation or sweeping of the water jet into the spa can be changed by adjusting the length and size of the inertance loop plates attached to the walls of the fluidic element itself. The inertance plates have inertance loop-forming grooves formed therein, one end of each inertance plate, forming a loop groove being juxtaposed over an aperture to a control passage and the other end of the loop groove being juxtaposed over a pass-through port or passage to the corresponding end of the loop on the loop groove in the opposing inertance plate to thereby form the frequency determining loop connecting the control ports of the fluidic oscillator. 
   The invention also features a mode disc which is secured to the front of the fluidic in such a manner as to allow it to be manually rotated by a spa user to change the outlet geometry of the fluidic element and thus the character of the fluidic stream. In one position, the mode ring has a slot which aligns with and provides a continuation of the fluidic exit geometry and thus allows the water jet to oscillate. Upon rotation of 90°, for example, the slot is perpendicular to the fluidic exit geometry, and this results in the edges of the oscillating wave being backloaded so that the output is a straight focused jet. The shape of the rectangle can be made with the generally round section to control the feel of the jet in the jet mode. In addition, it can be adjusted to angles in between to achieve progressively narrower oscillations. The mode control disc has a pair of depressions or slots to each side of the slot in the mode disc to enable easy and firm grasping between the user&#39;s fingers. 
   Air is routed through a central control valve. Air enters the rear of the spa nozzle housing and is kept separated from the water passages by O-rings. The air passes through two channels along either side of a water conditioning passage. The air goes to the top and bottom inertance plates of the fluidic oscillator. The inertance plates have an air channel in them to carry the air to an air entrainment hole or port downstream of the power nozzle. 
   Thus, the object of the invention is to provide an improved fluidic spa nozzle. A further object of the invention is to provide an improved fluidic spa nozzle which incorporates a manually movable mode-change disc to control the sweeping of the jet back and forth in the spa. 
   Another object of the invention is to provide an improved fluidic spa nozzle which incorporates inertance loop plates which are interconnected by a pass-through. Another object of the invention is to provide a structure which enables the air to be introduced into the spa nozzle just downstream of the power nozzle and to maintain the inertance loop substantially free of air and thus maintain the inertance loop operable. 
   The inertance loop is comprised of a pair of plates secured to said top and bottom walls, respectively, each plate has a groove cut therein forming the inertance loop and having one end of said groove juxtaposed over an aperture in one of said control ports and the opposite end of said groove being juxtaposed over a passage passing between the top and bottom walls to interconnect with the end of a groove of opposing plates secured to the top and bottom walls. The spa tub nozzle includes a water ingestion port in the passage for purging air from said inertance loop. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects, advantages and features of the invention will become more apparent when considered with the following specification and attached drawings wherein: 
       FIG. 1  is an exploded isometric view of a fluidic spa nozzle incorporating the invention, 
       FIG. 2A  is a sectional view of the assembled fluidic spa nozzle, and  FIG. 2B  is a sectional view taken on the plane of the device showing the fluidic silhouette, 
       FIG. 3A  is a front view of a schematic version of the device showing the mode disc, 
       FIG. 3B  is a schematic isometric view of the device showing the oscillating liquid jet, 
       FIG. 3C  is a schematic illustration showing the mode disc in a position to prevent sweeping, and 
       FIG. 3D  is a further isometric schematic view showing the straight flow. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to the exploded view of  FIG. 1 , the spa nozzle includes a main housing  10  which has an external threaded portion  11  for below the waterline securement or mounting by a gland nut (not shown) in the wall W of a spa, an air inlet barb  12  and a main water inlet barb  13 . The air inlet  12  is connected to a valve (not shown) for ON/OFF control. 
   The upstream end  14  of subhousing  15  has a cutout  16  ( FIG. 2A ) that aligns with the flow inlet  13  to control water flow rate from full to about 30%. Subhousing  15  has a flared or bell-shaped section  15 B and an annular rib  15 R which engages the inner wall of main housing  10 . The downstream end of the subhousing  15  has a hook element CHM which will be described later in connection with the securement thereto of the escutcheon  40 . 
   The fluidic oscillator element  20  includes an annular dam member  21  that receives an O-ring member  22  which engages the inner wall  23  of the upstream end  14  of subhousing  15  (see FIGS.  2 A and  2 B). This forms a water chamber WCP for feeding water into the fluidic itself. The fluidic oscillator per se is shown in silhouette form in FIG.  2 B and includes a plug P, a power nozzle PN for projecting a jet stream of water past a pair of control ports CP 1 , CP 2  through an interaction region IR which has sidewalls SW 1  and SW 2  which diverge or flare outwardly toward ambient and top TP and bottom BT walls. Top and bottom inertance plates  25  and  26 , respectively, are mounted on the top and bottom walls and have inertance loop forming grooves ILG (only one shown in  FIG. 1 ) formed in the faces thereof. One inertance loop coupling aperture is shown in the view taken in FIG.  1  and designated as ILC for inertance loop connection passage to interconnect the control ports CP 1  and CP 2 . A similar passage or opening is formed in the opposite control passage CP 1 , but in the opposite sidewall thereof. (See exploded view shown in  FIG. 1. ) 
   The opposing ends of the inertance grooves and the inertance loops themselves are juxtaposed over a pass-through passage PTP so that the inertance loop extends between the two control ports CP 1 , CP 2  and controls the frequency of oscillation of the fluidic oscillator. Thus, the inertance loop between the two control ports CP 1  and CP 2  is comprised of inertance loop coupling passages ILC (one for each control port), two inertance loop grooves ILG (one in each of plates  25  and  26 ) which are connected by the passthrough passage PTP. The fluidic oscillator operates in a conventional fashion as follows: the water jet issues through power nozzle PN and passes across the control ports adjacent thereto and due to some perturbance, the jet will be closer to one or the other control port CP 1  or CP 2 . This produces a pressure gradient across the jet at the control ports to switch the let to one side or the other and then the process repeats. As noted earlier, the length and size of the inertance loop plates attached to the control ports of the fluidic element set the oscillating frequency. The frequency oscillation or sweeping of the water jet into the spa tub per se can be changed by adjusting the length and size (area) of the inertance loops formed on the inertance loop plates. 
   An air passage or groove AG is formed in the top and bottom inertance plates for matching with other holes all in the body of the fluidic for air entrainment admission to air entrainment hole AH. In this embodiment the air entrainment hole AH is located downstream of the power nozzle PN. The fluidic interaction region IR has sidewalls SW 1 , SW 2  that diverge downstream of the power nozzle PN to form a “V” shape. To obtain sufficient air entrainment, the air entrainment hole must be located close to the power nozzle where the jet is still focused. If the air entrainment hole AH is moved further downstream, the moving (sweeping) jet is not over the hole for a sufficient period of time to allow sufficient air to be drawn in. 
   When the air entrainment hole AH is positioned close to the power nozzle PN to optimize air entrainment, some quantity of air would be drawn into the inertance loop constituted by the groove AG in inertance plates  25 ,  26 . Air is sufficiently less dense than water so its inclusion in the inertance loop would first raise the oscillating frequency, and then as more air contaminates the inertance loop, the oscillations would stop. 
   To solve this problem, a water ingestion port WIP is added to the inertance loop. In addition to slowing the frequency (desirable in this application), the key benefit of the water ingestion port WIP is to provide water to purge the air contamination from the inertance loop. Without the water ingestion port WIP, the air entrainment hole AH would need to be placed further downstream and less air would be entrained into the exiting water (undesirable). 
   Air entrainment may be enhanced by a slot structure SLO extending downstream of air entrainment port or hole AH, as is disclosed in Thurber et al application Ser. No. 09/899,547, filed Jul. 6, 2001, entitled SPA NOZZLES WITH AIR ENTRAINMENT, incorporated herein by reference. 
   Integrally molded with the fluidic is an annular ring  29  which receives a rotatable or movable mode change disc  30  which has tabs  31 ,  32  that are fitted into arcuate guide slots  33 ,  34 . Mode change disc member  30  is also retained in position by a snap-on escutcheon member  40 . Snap-on escutcheon member  40  has a cooperating latch member CLM which engages a cooperating hook member CHM on the downstream end of housing  15 . Mode change disc  30  has an elongated slot  35 . The important feature about mode-change disc  30  is the slot  35  and its orientation relative to the downstream end of the interaction region or chamber IR. As illustrated, the mode disc  30  is generally round and has a generally rectangular slot  35  therein. The slots  33 ,  34  and tabs  31 ,  32  allows the mode disc  30  to be rotated up to about 90° to change the outlet geometry and thus the sweep of fluid stream. At 0° rotation (FIGS.  3 A- 3 B), the slot  35  is aligned with the diverging ends of the fluidic oscillator. As shown in  FIG. 2B , the slot  35  is aligned with the width of the diverging end of sidewalls SW 1  and SW 2  of the interaction region IR, thus allowing the water jet to sweep. Thus at 0° rotation, the slot  34  provides a continuation of the exit geometry of the interaction region IR and allows the submerged jet to sweep or oscillate back and forth in the water of the spa tub. At 90° rotation, the slot  34  is perpendicular to the fluidic exit geometry. This results in the edges of the oscillating wave being backloaded, and the output is a straight focused jet. The rectangular slot  34  can be made larger with a generally round section to control the field of the straight jet in the jet mode. The disc  30  can be adjusted to angles from between 0° and 90° to achieve progressively narrower sweeping oscillations. 
   The mode control disc  30  has a pair of side slots or depressions F 1 , F 2  to each side of the slot in the mode disc  30  to enable easy, ergonomic and firm grasping between the user&#39;s fingers. 
   In the straight jet mode, the jet may have a pulsating sensation, depending on the size of the opening chosen. This pulsation feels twice as quick as the oscillations in oscillating mode due to the jet passing through the center twice per oscillation. 
   In the straight jet mode, the water is concentrated in a smaller area than the oscillation mode. Therefore, the momentum flux and intensity, is greater. Control of the flow rates can be accomplished by rotating the sleeve valve formed in the subhousing and discussed briefly above. 
   Air can be routed through the central control valve on the spa nozzle to a manifold, and an air line (not shown) from this manifold is connected to each spa nozzle housing via air barb fitting  12 . Air enters the rear of the housing and is separated from the water passages by the rear O-ring RO. The air passes through the two channels HC 1  and HC 2  on either side of the water chamber WCP. Air passages then turn 90° through aperture APP to the top and bottom inertance plates  25 ,  26  of the fluidic, and each of the inertance plates  25 ,  26  have an air channel AG in them to carry the air to the pass-through hole AH downstream of the power nozzle PN. 
   The fluidic oscillator can be set in any angular position. As illustrated in the drawings, the fluidic oscillator is constrained in its fore and aft position by being retained between the housing and the escutcheon. It is constrained from rotating by the friction of the rear O-ring. 
   While the invention has been described in relation to preferred embodiments of the invention, it will be appreciated that other embodiments, adaptations and modifications of the invention will be apparent to those skilled in the art.