Abstract:
The showerhead engine assemblies provide different combinations and variations of continuous, deflected, pulsating sprays, and aeration spray patterns including those that are adjustable enabling wide variations in the degree of aeration of the water passing through the showerhead, enabling wide variation of the characteristics of the water spray patterns. The spray patterns include a nondeflected, nonpulsating spray pattern; a deflected nonpulsating spray pattern; a nondeflected, pulsating spray pattern; and a deflected, pulsating spray pattern, while enabling the engine assembly to be self-cleaning. For pulsating spray modes, the showerhead engine assembly includes but five plastic parts and an O-ring seal; the parts being a stator, a spinner, an engager, a pressure plate, and a faceplate, openings beings disposed in the pressure plate and faceplate to enable fluid flow therefrom. Deflecting surfaces on the faceplate enable a variety of different flow patterns. Spinner rotation starts or stops depending upon the position of the spinner relative to the stator, since the stator includes a pair of stop flanges that engage and disengage with the spinner. When the spinner is disengaged and free to rotate, water flow through passages in the spinner cause spinner rotation, creating a vortex and pulsating spray patterns. The series of showerhead engine assemblies include component parts that are interchangeable, the number of component parts being minimal, the interchangeability reducing the number of spare parts necessary to repair the series of showerhead engine assemblies.

Description:
RELATED APPLICATIONS 
     This application claims priority from U.S. Provisional Application No. 60/128,289 filed on Apr. 8, 1999. 
    
    
     FIELD OF ART 
     This invention relates to showerhead engine assemblies and water aerators, and more particularly, to showerhead engine assemblies having different combinations of continuous and pulsating sprays. 
     BACKGROUND OF THE INVENTION 
     Numerous showerheads assemblies are known in the prior art that operate in multi-functional modes. These assemblies provide fixed spray patterns in combination with massaging action generated by either pulsating or whirling the water through the showerhead. Individual systems include: 
     (1) A selector disk removably and rotatably mounted inside the selector housing. The disk selector has an inlet end facing the inlet end of the selector housing, and an outlet end opposite the inlet end of the disk selector. The showerhead includes a selector face mounted inside the selector housing and a diffuser plate mounted inside the selector housing. 
     (2) A showerhead assembly enabling the selection of various forms of output streams, including a set of streams having a large diameter, rich in bubbles when the water pressure is high, a set of streams having a smaller diameter full of bubbles when the water pressure is low, or a spray instead of the bubbly stream. 
     (3) A showering system fed from a source of hot water that produces steam. A selectively controlled diverter is disposed within the conduit and diverts the water arriving from the source away from the showerhead and through the outlet in the form of a mist. The showerhead includes a nozzle-driven turbine. Apertures in a flow director plate, governed by a control plate, feed nozzles predetermined to vary the force of water delivered. The water force varies with the number of the nozzles that are open. 
     These systems have complex internal components which must be sealed relative to each other, are relatively expensive to produce, and due to the complexity of the components often do not operate in a manner which fully prevents leakage during use. In addition, the showerhead outlet ports often become obstructed by impurities causing almost random spray patterns. 
     What is needed is a showering system that overcomes the disadvantages of the prior art, that is economical to manufacture and durable in use, that operates effectively within a wide range of water pressures, that enables the person to select from a regular continuous spray, an aerated spray, a pulsating spray, and several combinations thereof, and that is energy efficient and yields spray characteristics that are better than conventional showerhead engine assemblies. 
     What is needed is a showerhead engine assembly having component parts that are interchangeable with other assemblies, the number of component parts being minimal, the interchangeability reducing the number of spare parts necessary for repair purposes, the assembly enabling various combination of spray patterns including jet spray, aeration, deflected spray, pulsating jet spray, and pulsating deflected spray, while providing self-cleaning convenience. 
     SUMMARY OF THE INVENTION 
     These needs are addressed by the preferred embodiments of the showerhead engine assemblies of the present invention. The term showerhead as used herein designates any device which attaches to a shower fluid supply through an inlet tube and creates a spray by changing the fluid pattern, including (1) standard showerheads, (2) pulsating showerheads, and (3) energy-savings, aerating showerheads. 
     In a first preferred embodiment of the showerhead engine assembly of the present invention comprises five plastic parts plus an O-ring seal; the parts being a stator, a spinner, an engager, a pressure plate, and a faceplate, openings beings disposed in the pressure plate and faceplate to enable fluid flow therethrough. Deflecting surfaces on the faceplate enable a variety of different flow patterns. Rotation of the spinner is dependant upon the particular spray pattern selected. The stator includes a pair of stop flanges that engage and disengage with the spinner. When the spinner is disengaged and free to rotate, fluid flow through passages in the spinner cause spinner rotation, creating a vortex. When the spinner is free to rotate, the combination of the spinner, stator, and pressure plate create pulsating action. 
     The spray patterns are formed external to the pressure chamber. The spray selection occurs on more than one plane, between the pressure plate and the faceplate, and the spray selection occurs with water at atmospheric pressure. The spray patterns are created by the deflecting surfaces disposed on the faceplate. Four basic spray patterns: (1) nonpulsating uninterrupted flow where the spinner is stationary; (2) nonpulsating deflected flow where the spinner is also stationary; (3) pulsating uninterrupted flow where the spinner is rotating; and (4) pulsating deflected flow where the spinner is rotating. 
     In a second preferred embodiment of the showerhead engine assembly of the present invention, the engine assembly comprises only a pressure plate and a faceplate, without pulsation. A mechanism for alignment purposes is preferably incorporated into the pressure plate and faceplate, since unless properly aligned, the water flow becomes random. Also, a detente mechanism can be used. The faceplate is identical to the faceplate in the first preferred embodiment. Two spray patterns are available: (1) nonpulsating uninterrupted flow; and (2) nonpulsating deflected flow. 
     The pressure chamber within the showerhead engine assembly disposed between the stator and the pressure plate must be sealed from the spray selection chamber. In contrast to conventional showerhead engine assemblies where high-pressure seals are needed to provide necessary sealing, the showerhead engine assembly of the present invention only needs to seal the pressure chamber from the spray selection chamber. 
     Additional embodiments include showerhead engine assemblies similar to the first and second preferred embodiments that include a self-cleaning action. Six self-cleaning pins disposed are normal to the plane of the spring wire. The circular spring nests in a circular slot in the pressure plate. Each of the six orifice holes in the pressure plate comprise a cluster of apertures disposed about a central opening. The pins rest into each of the central openings. As the relative position of the faceplate is rotated about the pressure plate-spring combination as spray selections are made, the edges of the faceplate force the pins to move back and forth axially within the central openings generating the self-cleaning action. The pins translate within the holes by the action of rotation of the shower faceplate itself, resulting in the self-cleaning action. 
     The advantages of the showerhead engine assembly of the present invention are numerous. These advantages include spray patterns formed external to the pressure chamber; and a dramatic reduction in the number of component parts, which keeps part count down, improves assembly time, reduces costs, and simplifies repair. The showerhead engine assembly of the present invention also provides crossing spray patterns; and families of showerhead engine assemblies that provide various spray patterns with interchangeable component parts. Other shaped and sized orifices in the faceplate enable a selection of a variety of spray patterns with varying spray characteristics. Rotation and realignment of the faceplate relative to the pressure plate changes the orifice configurations and the number of spray selection options. 
     For a more complete understanding of the showerhead engine assembly of the present invention, reference is made to the following detailed description and accompanying drawings in which the presently preferred embodiments of the invention are shown by way of example. As the invention may be embodied in many forms without departing from spirit of essential characteristics thereof, it is expressly understood that the drawings are for purposes of illustration and description only, and are not intended as a definition of the limits of the invention. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     FIG. 1 discloses an exploded perspective view of the preferred embodiment of the showerhead engine assembly of the present invention comprising a stator, a spinner, an engager, an O-ring, a pressure plate, and a faceplate retained within a handle of a hand-held showerhead; 
     FIG. 2A discloses an exploded perspective view of the downstream surfaces of the engager, the spinner, and the stator of the showerhead engine assembly of FIGS. 1 and 2B discloses an exploded perspective view of the upstream undersurfaces of the engager, spinner, and stator of FIG. 2A; 
     FIG. 3A discloses a perspective view of the upstream surface of the engager of the showerhead assembly of FIG. 1, and FIG. 3B discloses a perspective view of the downstream surface of the engager of FIG. 3A; 
     FIG. 4A discloses a perspective view of the upstream surface of the pressure plate of the showerhead assembly of FIG.  1  and FIG. 4B discloses a perspective view of the downstream surface of the pressure plate of FIG. 4A; 
     FIG. 5A discloses a perspective view of the upstream surface of the faceplate of the showerhead assembly of FIG. 1, and FIG. 5B discloses a perspective view of the downstream surface of the faceplate of FIG. 5A; 
     FIG. 6 discloses an enlarged side sectional view of the assembly of the engager, pressure plate, and faceplate of FIG. 1; 
     FIG. 7A discloses a side view of the hand-held showerhead assembly of FIG. 1, and FIG. 7B discloses a front view of the hand-held showerhead assembly of FIG. 1; 
     FIG. 8A discloses a front view of the faceplate of the showerhead engine assembly of FIG. 7B, the position of the faceplate being between deflected and nondeflected flow relative to the pressure plate; 
     FIG. 8B discloses a top view of the hand-held showerhead engine assembly of FIG. 8A; and 
     FIG. 8C discloses a bottom view of the hand-held showerhead engine assembly of FIG. 8A; 
     FIG. 9 discloses an exploded perspective view of a second preferred embodiment of the showerhead engine assembly of the present invention comprising a shell, a stator, a spinner, an engager, an O-ring, a pressure plate, and a faceplate; 
     FIG. 10A discloses a side view of the showerhead engine assembly of the present invention as used in the fixed showerhead assembly of FIG. 9; and 
     FIG. 10B discloses a side sectional front view of the showerhead engine assembly of FIG. 10A; 
     FIG. 11A discloses a perspective view of the downstream surface of another preferred embodiment of the faceplate of the showerhead engine assembly of the present invention, the faceplate having two spray selection modes of operation—aeration spray and nondeflected spray; 
     FIG. 11B discloses a perspective view of the upstream undersurface of the faceplate of FIG. 11A; and 
     FIG. 11C discloses an enlarged detail view of the one of the deflectors of the faceplate of the showerhead assembly of FIG. 11B; 
     FIG. 12A discloses a perspective view of the upstream surface of another preferred embodiment of the pressure plate of the showerhead engine assembly of the present invention, this preferred embodiment for use with an interchangeable faceplate, the faceplate being shown FIGS. 5A and 5B for a two-piece showerhead engine assembly; and 
     FIG. 12B discloses a perspective view of the downstream undersurface of the pressure plate of FIG. 12A; 
     FIG. 13 discloses an exploded perspective view of yet another preferred embodiment of the showerhead engine assembly of the present invention, with the showerhead engine assembly of FIG. 1 including a self-cleaning ring that cleans apertures within the pressure plate as the faceplate is rotated relative to the pressure plate; 
     FIG. 14 discloses an exploded perspective view of still yet another preferred embodiment of the showerhead engine assembly of the present invention, with a two-piece fixed showerhead engine assembly of FIG. 9, and with the self-cleaning ring shown in FIG. 13; 
     FIG. 15 discloses an enlarged, partial perspective view of the cooperative engagement between the self-cleaning ring and the pressure plate of FIGS. 13 and 14; and 
     FIGS. 16A,  16 B,  16 C, and  16 D show enlarged views of the cooperative engagement between the faceplate and the self-cleaning ring of FIGS.  13  and  14 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Attention is initially drawn to the drawings, as FIG. 1 discloses an assembly view of the preferred embodiment of the hand-held embodiment of the showerhead engine assembly  10 A of the present invention. FIGS. 7A,  7 B,  8 A,  8 B, and  8 C show additional views of the hand-held showerhead shell and casing  15 A. The showerhead engine assembly  10 A of the present invention comprises a stator  20 , a spinner  30 , an engager  40 , an O-ring  50 , a pressure plate  60 , and a faceplate  80 . 
     High-pressure water enters the back end of the showerhead shell of the present invention at between about 20 to 80 psi with a maximum flow of 2.5 gallons/minute @ 80 psi. The water is thrust through the stator  20  and into the spinner  30 , passing into and through the pressure plate  60  and is discharged through the faceplate  80 . The spinner  30 , O-ring  50 , and engager  40  are inserted into the pressure plate  60 . The stator  20  is snapped into the pressure plate  60  and the faceplate  80  is snapped into the engager. An essentially conventional hand-held shell  15 A is used. 
     Reference is now drawn to FIGS. 2A and 2B which disclose the downstream and upstream surfaces, respectively, of the stator  20 , spinner  30 , and engager  40 . Water enters the showerhead engine assembly  10 A of the present invention tangentially through four evenly-spaced passages  22  disposed at the periphery of the stator  20 . Such tangential flow generates a vortex in the pressure chamber within the showerhead engine assembly, causing the spinner  30  to rotate. 
     The stator  20  is a flat, circular disc. The stator  20  has a centrally disposed stator hub  21  with a centrally disposed orifice  24  for receiving the shaft of the engager  40  therethrough. The stator  20  has eight spokes, the spokes  23  being evenly and symmetrically spaced about the stator hub  21 . The spokes  23  extend from the stator hub  21  to the perimeter of the stator  20 . Four stator passages  22  are disposed on alternating spokes on the distal half portion of each spoke  23 . The stator peripheral passages  22  are defined by and are formed between a flag-shaped raised portion of the essentially flat surface of the stator  20 , the stator  20  being sloped in a rearward direction toward the shell  15 A. Abutting two of the opposing stator peripheral passages  22  are a pair of flanges  26  extending normal to the plane of the stator  20 . The flanges  26  extend from the stator upstream surface  20 A and engage the inner surface of the shell  15 A. This secures the stator  20  relative to the shell  15  thereby preventing any rotary motion of the stator  20  when the pressurized water enters the showerhead assembly and into the showerhead engine assembly.  10  of the present invention. The stator  20  remains engaged and retained by the shell during all spray selection patterns. The stator  20  also includes a pair of stopping ribs  28  extending from the stator downstream surface  20 B. The stopping ribs  28  serve to engage the spinner  30 , and block spinner rotation when the spinner  30  is positioned axially in the upstream direction toward the stator  20 . The stator ribs  28  are so positioned that when the spinner  30  is restricted from rotation, the pads  37  do not obstruct flow through the stator peripheral passages  22 . 
     The spinner  30  has a circular shape with a centrally disposed spinner hub  32 , an opening being disposed in the center of the spinner hub  32 . The spinner hub  32  has a generally tubular extension  35 , protruding outward from the spinner  30  extending toward the stator  20 . The tubular extension  35  nests within the stator hub  25 . The spinner  30  preferably has twelve blades  34  extending from the spinner hub  32  to the spinner perimeter, the positioning of the blades  34  being symmetrical and evenly spaced. The blades  34  extend in the axial direction and are so positioned that water entering through the stator passages  22  will propel the blades  34  when the spinner  30  is released from the stator  20  causing a spinning action. The blades  34  are essentially radial except that they are slightly offset from the spinner center, simulating the shape of a spiral. The spiral shape enhances rotation. Two arcuately-shape pads  37  opposing each other extend circumferentially about the perimeter of the spinner  30 , each pad  37  joining three of the blades  34  together. The blades  34  are not secured together. 
     When the spinner  30  is rotating, the pressurized water strikes the pads  37 , interrupting water flow. When the pressurized water does not strike the pads  37 , flow is continuous. The sequencing of interrupted and uninterrupted flow creates the pulsating effect. The two pads  37  interrupt water flow through the showerhead engine assembly  10 A of the present invention, causing the jet streams to have differing velocities, and thereby causing a “massage” action. The pads  37  are so configured that when the spinner  30  is engaged with the stator  20 , the spinner being stationary, the pads  37  are not in the path of the water flow, so that all flow is essentially continuous. Either expanding or reducing the number of blades  34  covered by each pad  37  generates other pulsation patterns. 
     As shown in FIGS. 3A and 3B, the engager  40  includes a stem-like member  42 . The engager upstream surface  40 A has a center section that forms a central chamber. Centrally disposed and extending in the upstream direction is the stem  42 . The stem  42  has a thicker inboard portion  42 A for nesting engagement with the spinner hub  32 , and a thinner outboard portion  42 B for nesting engagement with the stator hub  21 . A shoulder  44  is disposed between the stem inboard portion  42 A and the stem outboard portion  42 B. The shoulder  44  prevents axial movement of the spinner  30 . The spinner  30  moves axially with the engager  40  on the stem inboard portion  42 A. The stator  20  is secured relative to the shell  15 A. 
     The spinner  30  seats on the thicker inboard portion of the engager stem  42 , and the stator  20  seats on the thinner outboard portion  42 A of the engager stem  42 . In order to minimize the bearing surface of the spinner  30  on the engager  40 , a central passageway  31  extends through the spinner  30  and tapers inwardly, preferably on the upstream edge, which results in less of a frictional surface between the engager stem  42  and the spinner  30 . 
     The outer perimeter of the engager  40  is defined by an annulus  48  that surrounds the engager center section  45 . The annulus  48  is secured to the engager center section  45  by three radial spokes  46 , the engager radial spokes  46  being evenly spaced about the engager  40 . The inboard half of each spoke  46  is roughly three times as thick as the outboard half of each engager spoke  46  for purposes of strength. The engager spokes  46  divide the engager perimeter into three outer sections  47 , each perimeter section  47  having an arcuate segment of about 120 degrees. Each perimeter section  47  has a centrally disposed nub  50 , the nub  50  being less than a forty-five degree sector of each perimeter section  47 . The nubs  50  provide the engager  40  with elasticity and improve the secure engagement of the engager  40  with the pressure plate  60 . 
     Centrally disposed within the engager downstream surface  40 B is a recess  52  and a middle chamber  56 . Three evenly spaced ribs  54  extend radially outward between an inner tubular wall  53  defining the central recess  52  and an outer tubular wall  55  surrounding the middle chamber  56 . The ribs  54  divide the middle chamber  56  into three sections, each section having an arcuate segment of about 120 degrees. Each section is aligned with the three perimeter sections  47  of the engager  40 . 
     While the engager  40  is seated within the pressure plate  60 , the engager  40  moves axially within the pressure plate  60  with the faceplate  80 , the faceplate  80  moving axially with the manual selection of spray patterns. When the engager  40  is repositioned axially toward the shell  15 A, the spinner  30  is forced into engagement with the pair of opposing stopping ribs  28  disposed on two opposing blades  34  of the stator  20 . This engagement locks the spinner  30  relative to the stator  20 . When the engager  40  moves axially downstream with the faceplate  80 , the spinner  30  also moves axially toward the faceplate  80  on the engager stem  42 , releasing the spinner  30  from the stator  20 . This causes the high pressure water to pass between the blades  34  in the spinner  30  causing the spinning action. 
     The axial force is controlled by the size of the O-ring  50  sealing the engager stem  45 A inside the bore in the pressure plate  60 . The size of this O-ring  50  and shaft are determined by the size needed to transmit torque between the faceplate  80  and the engager stem  45 A. 
     FIG. 4A shows the pressure plate upstream surface  60 , and FIG. 4B shows the pressure plate downstream undersurface  60 B. The pressure plate upstream surface  60 A cooperatively engages the engager downstream surface  40 B, and the pressure plate downstream surface  60 B cooperatively engages the faceplate upstream surface  80 A. 
     The pressure plate  60  includes a central opening  64  for receiving the engager outer tubular wall  55 . The wall  65  defining the central opening  64  on the pressure plate upstream surface  60 A is ramped inwardly and outwardly. The inner section of the pressure plate upstream surface  60 A is surrounded by a concentric cylindrical wall  66 . The concentric wall  66  surrounds the engager annulus  48  during engagement. 
     The opening wall  65  is ramped having three each sloped upward segments  61 A, flattened top segments  61 B, sloped downward segments  61 C, and flattened base segments  61 D. The length and slope of the sloped upward segments  61 A is the same as the length and slope of the sloped downward segments  61 C. The length of the flattened top segments  61 B is the same as the length of the flattened base segments  61 D. The ramps  61  in the opening wall  65  separate the opening wall into six equal sections. Since the engager  40  moves axially and rotationally with the faceplate  80 , the ramps  61  cooperatively engage the engager perimeter sections  47 . When the engager  40  is in a forward position, the engager spokes  46  are aligned with the flattened base segments  61 D, and the ramps  61  nest within the open engager perimeter sections  47 . When the engager  40  moves rearward toward the shell  15 A, the ramps  61  are aligned with the engager spokes  46  that separate the engager perimeter sections  47 . 
     The midsection of the pressure plate  60  is divided into twelve pie-shaped sections. Alternating sections include a cluster  72  of jet orifices  73  that extend through the pressure plate  60 . Each cluster  72  of jet orifices  73  has a box-type configuration. The clusters  72  of jet orifices  73  are positioned on alternating sections. The openings are arranged in two groups of two, an upper group being aligned with and disposed above the lower group. The other alternative sections have no jet orifices. The outer section of the pressure plate upstream surface  60 A includes a circumferentially disposed recess  68  sandwiched between two annular flanges  67  and  69  for cooperative engagement with the hand-held showerhead shell  15 A. 
     The hub  62 B of the pressure plate downstream surface  60 B includes another series of three ramps  71  for cooperative engagement with three ramps  81  on the faceplate upstream surface  80 A. Each of the ramps  71  on the pressure plate downstream surface  60 B are out of phase and aligned with the ramps  61  on the pressure plate upstream surface  60 A. The top portion  71 B of each downstream ramp  61  is aligned with a ramp spacing  61 D disposed on the pressure plate upstream surface  60 A. The ramps  71  on the pressure plate downstream surface  60 B have the same shape and configuration as the ramps  81  on the faceplate upstream surface  80 A as hereinafter set forth. The hub  62 B of the pressure plate  60  and the hub  82  on the faceplate upstream surface  80 A are each divided into six equal sections—alternating sections including a ramp (either  71  or  81 ). The length of the top and bottom ramp sections of the engager  40 , pressure plate  60 , and faceplate  80  are each sized so that the faceplate  80  and the engager  40  move freely together into the proper axial position as shown in FIGS. 3B,  4 A,  4 B, and  5 A. The relative position of the ramps  71  and  81  moves the faceplate  80  axially relative to the pressure plate  60  during the manual selection of spray patterns. Again, each ramp  71  and  81  includes an upward ramped surface  71 A and  81 A and a downward ramped surface  71 C and  71 C. The length of each up-ramped surface  71 A and  81 A is the same and opposite to the slope of the opposing ramped surface  71 C and  81 C. The pressure plate downstream surface  60 B also includes a cylindrical flange for receiving the faceplate  80 . 
     The central opening  64  of the pressure plate  60  is surrounded by an annular sleeve  68 . A plurality of platforms  43  are arcuately positioned about the annular sleeve  68 . The pressure plate upstream surface  60 A includes a recess  63  disposed between an outer perimeter  67  and an outer rim  69  as shown in FIG.  4 A. The recess  63  enables the pressure plate  60  to be securely retained onto the shell  15  of the showerhead. The pressure plate  60  includes a circular lip  70  extending from the pressure plate downstream surface  60 B. The lip  70  is concentric with the central passageway  63 , and encases the faceplate  80 . 
     The faceplate  80  has a generally cylindrical shape, with a upstream surface  80 A as shown in FIG. 5A, and a generally flat downstream surface  80 B as shown in FIG.  5 B. The faceplate upstream surface  80 A includes a center shaft  84  that extends upstream toward the showerhead shell  15 A. The center shaft  84  of the faceplate  80  nests within the center portion of the engager  40 . Surrounding the shaft is a cylindrical wall having three notches  85 . Each notch  85  is evenly spaced and extends from the flat faceplate upstream surface  80 A to the distal end of the cylindrical wall. The notches  85  mesh with the engager ribs  54  downstream surface  40 B. 
     The center section of the faceplate upstream surface  80 A includes three ramps  81 , as already described, for cooperative engagement with the ramps  71  on the pressure plate downstream surface  60 B. 
     The outer section of the faceplate downstream surface  80 A includes twelve passages  92  of the same size and shape, each passage  92  being symmetrically spaced about the center shaft along a common circumference. Six of the passages  92 A are hollow and unobstructed for nondeflected flow. Alternating passages  92 B are divided into four equal quadrants by a pair of crossing portions  93 . The outer perimeter of the faceplate upstream surface  80 A is a cylindrical flange  88  for retention within the pressure plate  60 . The faceplate downstream surface  80 B includes convex bubble-shaped deflector surfaces  98  covering the passages  92 B. Deflected flow occurs when the bubble-shaped deflector surfaces  98  are aligned with the clusters  72  of jet orifices in the pressure plate  60 . Nondeflected flow occurs when the nondeflecting outlet passages  92 A are aligned with the clusters  72  of jet orifices in the pressure plate  60 . A spray-pattern selector  99  extends radially outward and then rearward from the perimeter of the faceplate  80 . The spray-pattern selector  99  enables a secure grasp for repositioning of the faceplate  80  relative to the shell  15  for spray pattern selection. Since the only jet impingement striking the faceplate  80  is through the bubble-shaped deflector surfaces  98 , the faceplate  80  only requires attachment to the engager stem  42  with a low force snap fit. 
     The spacing  81 D between each ramp is sufficient to enable ramps on opposing surfaces to nest therebetween during selected spray patterns. The ramps enable (a) the faceplate  80  and the engager  40  to move axially relative to the pressure plate  60 , and also (b) the spinner  30  to move axially relative to the stator  20 , alternately, engaging and releasing the spinner  30 . As the incoming spray alternately is projected through the bubble-shaped deflector surfaces  98  and the nondeflecting passages  92 A of the faceplate  80 , and the spinner  30  is alternately engaged and released, four distinct spray patterns are enabled. 
     The pressure chamber is the area between the pressure plate upstream surface  60 A and the shell  15 A. The spray selection chamber is positioned between the pressure plate downstream surface  60 B and the faceplate upstream surface  80 A. Water enters the stator  20  at between 12 and 18 psi and leaves the spinner  30  at between 7 and 14 psi and water leaves the pressure plate  60  at atmospheric pressure. The engager  40  acts as an adapter to cooperatively engage the pressure chamber with the spray selection chamber. The O-ring  50  is disposed onto the engager downstream surface  40 B, providing a seal between the pressure chamber and the spray selection chamber. 
     The pressure plate  60  is secured to the shell and does not move in either the axial or rotation positions relative to the shell. Similarly, the stator  20  is engaged with the pressure plate  60  and does not move either axially or rotationally relative to the shell. The faceplate  80  is rotated relative to the shell during manual selection of spray patterns. As the faceplate  80  is rotated relative to the pressure plate  60  during spray pattern selection, the faceplate  80  moves inward and outward axially—one complete rotation includes six inward positions and six outward positions. The faceplate  80  moves axially with alternate position selections, the pattern being A, A, B, B, A, A, B, B, A, A, B, and B for each complete rotation. The hole clusters in the pressure plate  60  are either aligned with the bubble shaped deflector surfaces or the passages disposed between the bubble shaped deflector surfaces, to provide a variety of spray patterns. 
     The preferred embodiment of the showerhead engine assembly of the present invention as depicted in FIGS. 1 through 8 includes two pulsated positions and two nonpulsated positions. Since the faceplate  80  is divided radially into twelve equal sections, the spray selection pattern is repetitive three times during a complete rotation of the faceplate  80 . 
     As the spray-pattern selector  99  is rotated to select a spray pattern, the axial position of the spinner  30  moves forward and backward relative to the stator  20  as described above. 
     When the engager perimeter sections  47  are in alignment with the pressure plate ramps  61 , the ramps  61  nest with the perimeter sections  47 , moving the engager  40  forward relative to the pressure plate  60 , and moving the spinner  30  forward relative to the stator  20 . Forward movement of the spinner  30  relative to the stator  20  releases the spinner  20  from engagement with the stator stopping ribs  28 . With the jets orifices  73  in the pressure plate  60  aligned with the nondeflecting passages  92 A in the faceplate  80 , the water jets continue in a straight, narrow (nondeflected) spray pattern. By continuing to rotate the faceplate  80  relative to the shell  15 , the bubble-shaped deflector surfaces  98  are brought into alignment with the jet orifices  73 . This time, the water jets are deflected into a larger spray pattern. During rotation of the spinner  30 , the pressurized water entering through the stator peripheral passages  22  is stopped by opposing pads  37  from exiting jet orifices  73  of the plate  60 . Rotation of the spinner  30  enables a deflected, pulsating mode and a nondeflecting, pulsating mode. 
     To operate in the nonpulsating modes, the faceplate  80  is again rotated. The ramps  61  on the pressure plate upstream surface  60 A move into alignment with the engager spokes  46 . This results in the engager  40  moving backward, bringing the spinner  30  into contact with the stator stopping ribs  28 . Such engagement blocks the spinner  30  allowing the water jets to exit the showerhead engine assembly  10  of the present invention in a continuous, uninterrupted spray pattern. With the jets orifices  73  in the pressure plate  60  aligned with the nondeflecting passages  92 A in the faceplate  80 , the water jets continue undeflected in a straight, narrow spray pattern. By continuing to rotate the faceplate  80  relative to the shell  15 , the bubble-shaped deflector surfaces  98  are brought into alignment with the jets orifices  73 . This time, the water jets are of a relatively constant velocity and deflect into a larger spray pattern. Once again, the correct alignment is secured by virtue of the detenting action of the engager  40  (which is snap-fit to the faceplate  80 ) into the pressure plate  60 . 
     The number of seals in the showerhead engine assembly of the present invention is independent of the number of spray patterns. Fewer seals result in fewer sealing surfaces. The pressure ranges in the showerhead engine assembly of the present invention are unique in that the fluid pressure of the water leaving the pressure plate  60  is essentially atmospheric. 
     Referring now to FIG. 9, an assembly view of a second preferred embodiment of the showerhead engine assembly  10 B of the present invention is shown. The showerhead engine assembly  10 B is a fixed unit being mounted onto a shell  15 B. The showerhead engine assembly comprises a stator  20 , a spinner  30 , an engager  40 , an O-ring  50 , a pressure plate  60 , and a faceplate  80  identical to the stator  20 , spinner  30 , engager  40 , O-ring  50 , pressure plate  60 , and faceplate  80  of the first preferred embodiment of the showerhead engine assembly of FIG.  1 . The shell  15 B is essentially the same as any conventional shell for a fixed showerhead assembly. FIG. 10A discloses a side view of the showerhead shell and casing of FIG. 9; and FIG. 10B discloses a sectional front view of the showerhead engine assembly of FIG.  10 A. 
     The shell  15 B is part of the permanent attachment mechanism that is welded to the pressure plate  60 , and the shell  15 B is affixed directly to the water connection mechanism of the fixed unit shown in FIG. 9. A bushing is threadedly attached to the shell  15 B. The shell further includes crossing rods that divide the shower spray into equal quadrants (not shown). Care is taken to prevent any welding at locations other than the main weld. In some instances dissimilar materials are used, such as (acrylonitrile-butadiene-styrene) or Acetal, to limit the weld surface. Alternatively, the spinner  30 , engager  40  and stator  20  are assembled onto the pressure plate  60  and the showerhead engine assembly of the present invention is then welded to the shell. Then, the faceplate  80  is pressed onto the engager  40  and the engager  40  is firmly seated against the stator  20 . 
     FIGS. 11A and 11B disclose the downstream and upstream surfaces, respectively, of an alternate embodiment of a faceplate  180  for use with the showerhead engine assembly of the present invention. This faceplate  180  shown provides aerated spray, and nondeflected spray. When used with a spinner and stator, pulsating selection modes can also be provided. This faceplate  180  is compatible with the pressure plate  60 , engager  40 , spinner  30 , and stator  20 , and shell of FIG.  1 . The aerating flow is at near atmospheric pressure. The aerating flow passages  192 B alternate with nondeflected passages  192 A and include an inlet head  196  centrally disposed and positioned on the faceplate upstream surface  80 A. As shown in FIG. 11C, each inlet head  196  is surrounded by eight spokes  197  radially extending therefrom. The inlet heads  196  and spokes  197  are integral with the flow passages  192 B—the spokes  197  do not rotate. The inlet head  196  is dome-shaped. Water jets passing through the pressure plate  60  strike the inlet heads  196 , disrupting the water jets while entraining air into the flow passages  192 B. The surface tension forces are sufficient to divert the path of the water jets so that they fail to leave the inlet head  196  cleanly and becomes attached to the top face inlet head  196 . Once attached to the surface, the water jets tend to remain attached due to surface tension forces (Coanda effect). This occurs when a water jet strikes the convex surface of the inlet head  196 , generating internal pressure forces that effectively entrain the water jets towards the surface. The inlet heads  196  can be used with the bubble-shaped deflector surfaces  98  to provide deflected and aerated spray. The inlet heads  196  can also be used with the spinner  30  and stator  20  to provide massaging spray modes. 
     These water streams are redirected by impinging the jets upon various deflector surfaces disposed within the faceplate  80 . These deflector surfaces are positioned within alternating openings in the faceplate  80 —an exploded detail view of an aerating deflector surface is shown in FIG.  11 C. The water jets pass through an opening and are not deflected or strike a series of deflector surfaces and are redirected, resulting in a more diverse and less directed spray pattern. Spray pattern selection occurs by rotating the faceplate  80  relative to the pressure plate  60 . The faceplate  80  is keyed and press fitted to the engager  40 . The rotation of this assembly results in the open hole or the deflector surfaces aligned with the jet orifices  73 . 
     FIGS. 12A and 12B disclose another preferred embodiment of a pressure plate  260  for the showerhead engine assembly of the present invention. In this embodiment, the hub portion of the pressure plate  260  has been modified, eliminating ramp features  61  and  71 , and including a central boss to receive faceplate boss  84 . This pressure plate  260  is compatible with the faceplate  80  of FIG. 5 to form a two-piece assembly. Since connection to the engager is not required, no pressure seal is required, and O-ring  50  can be eliminated. The assembly provides only two modes of operation: (1) nondeflected, and nonpulsated spray; and (2) deflected nonpulsated spray. Again spray selection is made by rotating the faceplate  80  relative to the pressure plate  260 . This enables the faceplates and the pressure plates to be interchangeable with similar components in the other assemblies, reducing the number of replacement parts needed for stocking inventory. A detent feature can be included between faceplate  80  and pressure plate  260 . 
     Referring now to FIGS. 13,  14 ,  15 ,  16 A,  16 B,  16 C, and  16 D, a novel self-cleaning showerhead engine assemble is shown. FIG. 13 discloses an assembly view of a preferred embodiment with the showerhead engine assembly of FIG. 1 including a self-cleaning ring  110  that cleans apertures within the pressure plate  60  as the faceplate  80  is rotated relative thereto. Similarly, FIG. 14 discloses an assembly view of the same self-cleaning ring  110  shown in FIG. 13 with the showerhead engine assembly of FIG.  9 . 
     Six self-cleaning pins  103  are disposed normal to the plane of the spring wire ring  105 . The jet orifices  173  now comprise a primary central opening  173 A with four smaller openings  173 B intersecting the central opening  173 A (see FIG.  16 D). Each pin  103  of the spring wire ring  105  is positioned in a central opening  173 A. The pin  103  is made to translate within the holes  65  by the action of rotation of the shower faceplate  80 , resulting in a cleansing action. 
     As the relative position of the faceplate  80  is rotated about the shell-spring combination as spray selections are made, the edges of the faceplate  80  force the pins  103  to move forward and backward in an axial direction within the jet orifices  173 . Both the jet orifice  173  and the pin  103  are tapered and the upward movement of the pin  103  into the jet orifice  173  results in the inside edge of each of jet orifice  173  to be opened and flushed. 
     FIG. 15 discloses an exploded view of the cooperative engagement between the self-cleaning spring-wire ring and the pressure plate  60  of FIGS. 13 and 14; and FIGS. 16A,  16 B,  16 C, and  16 D show exploded views of the cooperative engagement between the faceplate  80  and the self-cleaning ring of FIGS. 13 and 14. 
     While the self-cleaning embodiments are shown with the preferred embodiment of FIG.  1  and FIG. 9, one skilled in the art will readily recognize that these principles regarding self-cleaning can be readily applied to all of the other embodiments depicted herein, In addition to being applicable to both hand-held and fixed showerheads, the principles of the present invention are also applicable to other type of shower, nozzle, and sprinkler configurations including lawn sprinklers, dental appliances, and sprinkler systems in manufacturing and process control operations. 
     It is evident that many alternatives, modifications, and variations of the showerhead engine assembly of the present invention will be apparent to those skilled in the art in light of the disclosure herein. It is intended that the metes and bounds of the present invention be determined by the appended claims rather than by the language of the above specification, and that all such alternatives, modifications, and variations which form a conjointly cooperative equivalent are intended to be included within the spirit and scope of these claims.