Abstract:
A flow shut off or throttling valve is provided in a sprinkler nozzle housing to enable a nozzle to be changed without having to turn off a flow pressure source. The valve intersects a flow path through the nozzle housing and has an opening such that when the opening is aligned with the flow path, a flow stream can flow unobstructed through the flow path. The valve is movable between a fully open position in which the opening is aligned with the flow path and a closed position which blocks the flow stream from flowing to a nozzle disposed at an outlet passage of the flow path. The valve may be constructed to be either slidable or rotatable between the two positions, and is actuated by a gearing arrangement which is operable at the exterior of the nozzle housing. The external valve actuator may function as a physical barrier to retain the removable nozzle in the nozzle housing when the valve is open and to disengage the nozzle when the valve is closed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a divisional of U.S. patent application Ser. No. 11/670,715, filed Feb. 2, 2007, which is a divisional of U.S. patent application Ser. No. 10/015,588, filed Dec. 17, 2001, which claims priority of U.S. provisional application Ser. No. 60/255,742, filed Dec. 15, 2000. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a flow shut off or throttling valve in the nozzle housing of a sprinkler for limiting or preventing flow of water to the nozzle. 
         [0004]    2. Background of the Invention 
         [0005]    In order to achieve suitably irrigate an irregularly shaped area of land surface or near the borders of a land parcel, it may be desirable to change the distribution profile or configuration in a sprinkler to adjust the coverage range, distribution angle, etc. As a result, several different types of sprinklers have been offered to address this need. 
         [0006]    For example, U.S. Pat. Nos. 3,323,725 to Hruby; 3,383,047 to Hauser; and 4,729,511 to Citron each discloses a sprinkler having various structures for restricting a flow of water through the flow path through the sprinkler. However, restriction of the flow also results in a loss in pressure of the flow exiting from the nozzle. Such limited adjustment capabilities, moreover, are frequently inadequate to provide adequate or even coverage to edges, corners, or more unusual boundaries of a parcel of land to be irrigated. 
         [0007]    U.S. Pat. No. 5,234,169 to McKenzie, on the other hand, discloses a sprinkler which provides a removable nozzle and a camming mechanism for expelling the nozzle from the flow passage in a nozzle housing. It is thus possible to achieve a greater range of distribution profiles with the ability to change the nozzle altogether, relative to the sprinkler systems in the prior art referenced above. With this sprinkler, however, it is necessary to turn off a flow of water to the sprinkler in order to avoid getting wet during the nozzle exchange process. 
         [0008]    Similarly, U.S. Pat. No. 6,085,995 to Kah, Jr. et al. discloses a sprinkler in which a plurality of different nozzles are provided in the nozzle housing, with each nozzle effecting a different distribution profile from the others. A nozzle selection change is easily performed by operating a selection mechanism provided on the nozzle housing. With this sprinkler, however, the plurality of nozzles are provided on a common unit, and a user may not need all of the different types of nozzles provided in the set. 
         [0009]    In U.S. Pat. No. 5,762,270 to Kearby, et al, the disclosed sprinkler unit includes a valve provided in the flow path through the sprinkler housing for stopping the flow through the nozzle for facilitating a nozzle change. The valve, however, is physically disposed within the flow path, regardless of whether the valve is in an opened position or a closed position. Such placement of the valve requires the flow stream to flow around the valve enroute to the nozzle when the valve is open, thus resulting in increased turbulence in the flow stream and pressure loss of the flow exiting from the nozzle. 
         [0010]    It is thus desirable to provide a sprinkler having a removable nozzle and a mechanism for stopping the flow through the nozzle at the sprinkler location, wherein the presence of the mechanism does not introduce a pressure loss to the flow exiting the sprinkler. 
       SUMMARY OF THE INVENTION 
       [0011]    In a primary aspect of the present invention, a flow control and shut off valve which has a simple configuration is provided in a sprinkler, and can be actuated from the top or side of the nozzle housing to shut off or throttle the flow to one or more sprinkler nozzles. The valve throttles or shuts off a stream of water flowing through the flow path in the nozzle housing at a location upstream of the nozzle, so that the nozzle can be removed and exchanged without having to turn off the water supply to the sprinkler. 
         [0012]    The valve can be formed as a simple and thin component which can be made of a molded plastic. The valve is disposed in the nozzle housing and can be moved in and out of a flow path through the nozzle housing a valve controller or actuating element, which is engaged with a set of gear teeth molded onto the valve. A tight seal around the valve is achieved by the mating fit between the smooth plastic surfaces of the valve and the valve seat or by the insertion of “O” rings in the valve seat areas. The valve may be a flat or curved component and may operate in a slot or in a cavity molded into the nozzle housing. In each case, an opening in the valve is aligned with the flow path through the nozzle housing so that all the surfaces and edges of the valve are completely out of the flow path when the valve is in a fully opened position. 
         [0013]    The flow control valve of the present invention may provide the ability to throttle or shut off the flow only to a primary nozzle while allowing the flow to continue at full pressure to at least one shorter range secondary nozzle, to thereby maintain good atomization for uniform precipitation close to the sprinkler. 
         [0014]    In another aspect of the present invention, a nozzle retention member may be mechanically linked to the shut off valve so that when the flow shut off valve is moved to a closed position, the nozzle retention is automatically disengaged so that the nozzle may be removed and exchanged while the sprinkler remains pressurized. 
         [0015]    The valve may be actuated by a manual shut off valve actuation ring rotatably mounted around the outside of the nozzle housing. Additionally, selectable stream break-up or deflection lugs which can be moved into the nozzle stream for range control may be mounted on the manual shut off valve actuating ring around the outside of the nozzle housing. Such an arrangement eliminates the need to include a separate stream breakup screw in the nozzle housing, as commonly used in many prior art sprinklers to secure a nozzle in the nozzle housing. 
         [0016]    In one embodiment of the invention, the valve is preferably provided in the nozzle housing of a rotary driven sprinkler and is formed as a sleeve valve having an axis of rotation which is displaced from the rotational center line of the sprinkler to enable straightening of the flow passing between the valve and upstream of the nozzle in a lateral side passage portion of the flow path through the nozzle housing. Generally, the lateral side passage portion extends at an angle from a vertical main portion of the flow path to lead the flow path out of the nozzle housing via the nozzle. 
         [0017]    In another embodiment of the invention, the valve is formed as a cone-shaped element and is disposed in the nozzle housing to intersect the flow passage from the side to shut off the flow through the nozzle passage. 
         [0018]    All of the configurations of the valve allow a stream to flow fully unobstructed through the flow path with no valve pressure loss when the valve is in a fully opened position. 
         [0019]    All of the nozzle housing valve configurations are preferably made to be operated from the top of the nozzle housing or the side of the nozzle housings and to include an indicator on the nozzle housing to indicate the opened or closed state of the valve. 
         [0020]    Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is a cross-sectional view of a rotary driven nozzle housing on top of a stationary sprinkler body showing a horizontally placed flow throttling and shut off valve in the nozzle housing. 
           [0022]      FIG. 2  is a cross-sectional view from the top through the plane II-II indicated in  FIG. 1  through the nozzle housing showing a vertical portion of the flow path with a throttle valve in a fully opened position to the left in the figure and the valve gate aligned with the flow path. 
           [0023]      FIG. 3  is a cross-sectional view from the top through the plane II-II indicated in  FIG. 1  through the nozzle housing showing a vertical portion of the flow path with a throttle valve in a fully closed position to the right. 
           [0024]      FIG. 4  is a cross-sectional view of an entire rotary driven sprinkler including nozzle housing and body showing the placement of an arc setting shaft, flow valve control shaft and components of a gear and water turbine drive. 
           [0025]      FIG. 4A  is a partial sectional view from the top of the sprinkler showing the arc set, idler reversing gear and indicator member gear. 
           [0026]      FIG. 5  is a cross-sectional view of a rotary driven nozzle housing having a rotatable sleeve valve positioned with its center line offset from the center line of rotation of the sprinkler and a valve actuation shaft accessible at the top of the sprinkler housing. 
           [0027]      FIG. 6  is a cross-sectional view of a rotary driven nozzle housing including a cone-shaped sleeve valve intersecting the flow passage through the nozzle housing. 
           [0028]      FIG. 7  is a cross-sectional view of a rotary driven nozzle housing with a rotatable sleeve valve connected through an idler gear to a ring gear around the outside circumference of the upper nozzle housing, wherein the ring gear has a serrated outside circumference to facilitate manual operation thereof. 
           [0029]      FIG. 8  is an elevational view of the nozzle housing of  FIG. 7  and showing the ring gear as having structure configured to retain or release the changeable nozzle in the nozzle housing. Also shown are selectable stream break-up lugs that can be moved into the stream by further rotation of the ring beyond a position at which the flow valve is opened. A nozzle alignment and removal lug is shown on the bottom of the nozzle. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0030]    Referring to  FIGS. 1-3  of the drawings, a first preferred embodiment of the present invention is shown in which an upper portion of a rotary driven sprinkler  1  includes a cylindrical nozzle housing assembly  2  mounted for rotation about axis X-X on top of a sprinkler stationary body or riser assembly  4 . The riser assembly  4  has an opening  3  at its upper end in which an output drive shaft  5  is received. Output drive shaft  5  extends above the riser assembly  4  and is connected to the nozzle housing assembly  2  for rotationally driving the nozzle housing assembly. 
         [0031]    A flow path through the sprinkler is established via a center flow passage  31  and an outlet passage  33 . Center flow passage  31  is defined by drive shaft  5  and an interior cylindrical portion formed centrally in chamber  10  of nozzle housing  12 . Center flow passage  31  leads into outlet passage  33  which is arranged at an angle relative to the axis X-X. As can be seen in  FIG. 1 , water flowing through the flow path thus flows from a water source (not shown) into the output drive shaft  5  of sprinkler body  4 , out through flow opening  25  of output drive shaft  5  and into nozzle housing  12 , through outlet passage  33  and exiting the nozzle housing  12  after passing through a nozzle  34  disposed in outlet passage  33  for distributing a flow of water in accordance with a profile or range enabled by nozzle  34 . 
         [0032]    Nozzle  34  is removably secured in the outlet passage  33  of the flow path in the nozzle housing  12 . The removable nozzle  34  is retained in place by a range control screw  38 . Furthermore, a turning and flow straightening guide  16  is provided in the flow path just upstream of the nozzle  34  in the flow passage  33 . 
         [0033]    The distribution range and/or profile of the stream exiting nozzle  34  can be controlled by range control screw  38 , which is provided in an opening  44  in nozzle housing  12  which is aligned with nozzle  34  in outer passage  33 . Range control screw  38  controls the distribution range by deflecting the flow stream exiting through nozzle  34 , and is accessible for adjustment from the top of nozzle assembly  2 . 
         [0034]      FIG. 1  also shows a second hollow shaft  6  which is concentric with output drive shaft  5  and is used for setting the arc of oscillation by rotationally positioning one arc control contact relative to the other. An arc setting gear  7  is attached to the outer hollow drive shaft  6  by serrations formed on one or both interfacial surfaces. The contacting edges between arc setting gear  7 , sprinkler housing  4  and outer shaft  6  are sealed by an “O” ring to the stationary sprinkler housing  7  to prevent water from penetrating into the sprinkler housing. 
         [0035]    As can be seen in  FIGS. 4 and 4A , arc setting gear  7  engages a gear  69  formed at the base of an arc set shaft  71 , which can be accessed from the top of nozzle assembly  2  to set the arc of oscillation. An arc set indicator  50  is viewable at the top of nozzle assembly  2 . Optionally, arc set indicator  50  can be used to also set the arc from the top of the nozzle housing as well as serving as an indicator, instead of or in addition to shaft  71  as an arc set controller. The arc set indicator  50  includes a gear  68  which is engaged with an intermediate idler gear  80 , which in turn is engaged with a gear  70  of arc set shaft  71 . Thus, arc set indicator  50  is connected to arc setting gear  7  via gear  69  of shaft  71 , gear  70  of shaft  71 , idler gear  80 , and gear  68  of arc set indicator  50 . 
         [0036]    Idler gear  80  is provided between gear  70  on connecting shaft  71  and gear  68  of arc set indicator  50  for reversing the rotation direction of the arc setting indicator  50  from that of the rotation movement of the arc control contact member being set. This is an important feature since it allows the arc set shaft  71  and the indicator  50  to be turned in the same rotational direction as a change in the arc of oscillation occurs. That is, the indicator will reflect an increase in arc of oscillation by turning in the same direction that the arc set shaft  71  is being turned to effect such an increase, for example. Also, when nozzle housing  2  is rotated to its fixed side of the arc, the indicator will then point to where it will oscillate to for ease of arc setting. This is advantageous because to increase the arc of oscillation, e.g., by rotating the arc set shaft in the clockwise direction, the arc control contact that is being rotated clockwise must be shifted further counter-clockwise so that it does not trip the reversing mechanism as soon. This aspect of controlling the arc of oscillation is discussed more fully in, for example, U.S. Pat. No. 4,901,924. 
         [0037]    Additionally, arc of oscillation setting of the output drive shaft is more thoroughly discussed in U.S. Pat. Nos. Re 35,037; 5,417,370; and 4,901,924, the disclosures of which are hereby fully incorporated by reference. 
         [0038]    Nozzle housing assembly  2  includes a housing body  12  and a bottom plate  11  attached to housing body  12  by sonic welding or other attachment means, to thereby define a chamber  10  in the nozzle housing  12 . A shut off valve  9  is formed as a simple slidable shut off piece  13  and is positioned in chamber  10  across the center flow passage  31  of the flow path through sprinkler body  4  and nozzle housing  12  at the top of output drive shaft  5 . Shut off valve  9  includes a valve gate  17  formed as an opening in slidable piece  13 , and is slidable between a fully opened position in which valve gate  17  is aligned with opening  25  in the flow path ( FIG. 2 ), and a fully closed position in which valve gate  17  is moved entirely out of the flow path such that flow passage  31  is blocked at opening  25  of drive shaft  5  ( FIG. 3 ). Slidable shut off valve  9  also includes gear teeth formed along one side edge for engaging the gear of shut off valve actuation shaft  20  ( FIGS. 2 ,  4 ), whereby valve  9  is moved between the fully opened position and the fully closed position by turning shut off valve actuation shaft  20 . Moreover, slidable valve piece  13  is guided by guide rails  14  formed on nozzle housing bottom plate  11 , while being moved by the gear of actuation shaft  20 . An “O” ring seal  30  is shown surrounding the flow passage  31  at opening  25  into the nozzle housing, to serve as a water tight seat for the valve piece  13 . 
         [0039]    A recess  15  is formed on the underside of sliding shut off valve member  13  to allow flow to continue at full pressure to a secondary stagger passage nozzle  41  which is separated from the primary nozzle, to provide water coverage fall out close-in to the sprinkler. 
         [0040]    As further shown in  FIG. 1 , a recess  42  is formed at and extends around the top of nozzle housing  12 . A plate  39  and a rubber cover  40  are received in recess  42 , wherein the plate  39  provides rigidity for supporting the rubber cover  40  and is attached to the nozzle housing  12  by sonic welding or other attachment method. Plate  39  has openings where required, such as for exposing the arc set indicator  50 , the shut off valve actuation shaft  20 , etc. 
         [0041]    Preferably, the rubber cover  40  is fixed in the recess  42  with the plate  39  by rubber holding plugs fitting into holes in the plate  39  (not shown). However, other holding devices can be used. An opening  56  in rubber cover  40  is aligned with opening  44  in the nozzle housing  12  to access the stream-deflecting range control screw  38  through a slit  58  in rubber cover  40 . An “arrow” marked on cover  40  indicates radial the position of the stream outlet opening  33  so that it can be quickly determined with a glance at the top of nozzle housing assembly  2 . Also, arc set indicator  50  extends through an opening  64  in the rubber cover  40  aligned with an opening  48  in plate  39  and to the top surface of the rubber cover  40 . 
         [0042]    Arc set shaft  71  and flow throttling and shut off valve actuation shaft  20 , as seen in  FIG. 4 , extend to the top of rubber cover  40  and are accessible from the top through holes  95  and  96  formed therein. The position of the shut off valve can also be viewed and/or indicated at the top cover  40 , since less than one turn is required for full opening or closing of the flow shut off valve. 
         [0043]    Referring now to  FIG. 5 , a second preferred embodiment of the present invention is shown in which an upper portion of a rotatable sprinkler  101  includes a cylindrical nozzle housing assembly  102  mounted for rotation about axis X-X on top of a stationary sprinkler body assembly  104 . The stationary sprinkler body assembly  104  is connected to a source of water and has an opening  103  at its upper end through which an output drive shaft  105  exits stationary sprinkler body  104  (riser assembly) for connecting to nozzle housing assembly  102 . 
         [0044]    The output drive shaft  105  is hollow as shown in  FIG. 5 , and is attached to nozzle housing assembly  102  through a snap collar  108  which can be glued or sonic welded to the nozzle housing  115 . 
         [0045]    A flow path is defined from the water source through output drive shaft  105 , into a central cylindrical chamber  169  formed in nozzle housing  115 , and through a side passage  133  arranged at an angle relative to axis X-X and extending to a stream exit opening  132  leading out of nozzle housing  115 . 
         [0046]    A removable nozzle  134  is fitted in stream exit opening  132  of nozzle housing  115 , and is held in the nozzle housing by a stream break-up or deflection screw  138 . The nozzle has a primary stream exit opening  141  and optionally may have one or more secondary flow openings  140  for close-in stream break-up and coverage by the sprinkler. Flow straightener  150  is provided upstream of the nozzle for guiding a flow stream flowing through the flow path through sprinkler  101  after the change in direction from the vertical orientation of cavity  169  to the angled orientation of side passage  133 . 
         [0047]    Flow from the sprinkler body assembly  104  up through the nozzle drive shaft  105  and into the nozzle housing  115  and to the nozzle  134  is controlled by a sleeve valve  160  and can be shut off to allow removing and/or changing the nozzle  134  to a different nozzle for effecting a different flow rate or stream angle, if desired, even when the sprinkler is connected to a pressurized source of water. 
         [0048]    The rotary sleeve valve  160  has an opening  161  at least the size of the transition area forming the junction between the central portion of the flow path and the angled side passage  133 , and can be operated by turning a geared operator screw  165  to align the opening  161  in sleeve valve  160  with the side passage  133  in the nozzle housing  102 . 
         [0049]    As the secondary opening  140  of nozzle  134  is downstream of valve opening  161 , flow to secondary nozzle  140  is throttled or opened and closed along with flow to the primary nozzle opening  141 . 
         [0050]    Sleeve valve  160  has gear teeth  162  formed around its top end, as shown in  FIG. 5 , to cooperate with gear teeth on the operator screw  165 , and is configured to rotate about axis Y-Y in cavity  169 . The operator screw  165  can extend to the top of nozzle housing assembly  102  so as to allow opening and closing the valve from the outside during sprinkler operation. 
         [0051]    The gear ratio of the operator screw  165  to the sleeve valve gear  162  can be made 1:1. Since a full revolution of the operator screw  165  is not required to open and close the sleeve valve  160 , an arrow head recess  168  may be provided on the top of operator screw  165  to indicate a valve open or closed position on the top of the sprinkler nozzle housing assembly  102 . 
         [0052]    A third preferred embodiment of the present invention is shown in  FIG. 6 . This embodiment is similar to the second embodiment in that a nozzle housing assembly  202  is rotationally mounted on a stationary riser assembly  204 , and includes a rotatable flow shut off valve  260  mounted in the nozzle housing around the flow path for intersecting the same. Flow shut off valve  260 , however, is conically-shaped and has a valve opening  261  intersecting the flow passage  233  through the nozzle housing assembly  202 , at a position between the removable nozzle  241  and a flow straightening element provided in the flow path. 
         [0053]    Nozzle  241  may also include a secondary nozzle area  250 . As in the case of  FIG. 5 , flow to secondary nozzle  250  is throttled or opened and closed along with flow to the primary nozzle opening. 
         [0054]    The conically-shaped flow shut off valve member  260  is operated by gear teeth  262  formed around its bottom end and connected for external operation from the top or side of nozzle housing assembly  202  by gear  265 . 
         [0055]    In this embodiment, nozzle housing  215  includes a centrally positioned arc set shaft  275  which is concentric with the nozzle drive shaft  205  and which is connected to the top of nozzle housing  215  via an arc set indicating and setting mechanism. As shown in  FIG. 6 , the arc set indicating and setting mechanism includes an arc set indicating cylinder member  280  having an upper smaller section  282  rotatably fitted in a correspondingly sized cylindrical opening  283  in the nozzle housing  215 . 
         [0056]    The arc set indicating cylinder member  280  has a lower larger section  284 . An “O” ring seal  286  is provided to prevent flow from leaking to the outside while allowing the arc set indicating member  280  to be turned to set a desired arc of oscillation of the nozzle housing assembly  202  by the rotary drive mechanism (not shown) housed in the sprinkler body housing assembly  204 . Such an arc set control mechanism is shown and described in U.S. Pat. No. 4,901,924, issued Feb. 20, 1990 and U.S. Pat. No. 5,417,370, issued May 23, 1995, the disclosures of which are incorporated herein by reference as though fully set forth. 
         [0057]      FIGS. 7 and 8  show a fourth preferred embodiment of the present invention, which includes the nozzle housing assembly and flow shut off valve described above in connection with the embodiment shown in  FIG. 5 . The fourth embodiment is a variant of the second embodiment in which a removable nozzle  334  is now retained at  380  in the nozzle housing assembly  302  by a rotatable nozzle retention and flow shut off control ring  375  around the outside of the cylindrical nozzle housing  315 . 
         [0058]    Here, nozzle  334  includes a primary opening  350  and one or more secondary openings  352 , again downstream of a rotary shut off and throttle valve  360  described below. 
         [0059]    The nozzle retention and flow shut off control ring  375  as shown in  FIG. 8  has recesses  390  and  391  which enables nozzle  334  to be removed from nozzle housing  315  when control ring  375  is rotated so that one of recesses  390  and  391  is aligned over nozzle  334 . When neither of recesses  390  and  391  are aligned with nozzle  334 , control ring  375  forms a barrier to thereby retain nozzle  334  in the nozzle housing  315  against the water flow pressure forces. 
         [0060]    The nozzle retention and flow shut off control ring  375  is connected to the rotary sleeve valve  360  by gear teeth  376  formed around the inside circumference of the nozzle retention and flow shut off ring  375 . Gear teeth  376  cooperate with teeth  366  formed on geared operator screw  365 , which teeth  366  are in turn connected to teeth  362  of the rotary sleeve valve  360  for rotating the sleeve valve to align opening  361  formed in the barrel of the sleeve valve  360  with flow passage  333  in the nozzle housing  315 . 
         [0061]    As previously described with respect to the embodiment of  FIG. 5 , such arrangement opens and closes off a flow to the removable nozzle  334 . 
         [0062]    Because control ring  375  has a greater diameter than that of sleeve valve  360 , the inner circumference of control ring  375  is capable of accommodating more gear teeth  366 . For example, a 40° rotation of the control ring  375  may achieve a 120° rotation of the rotary sleeve valve  360 . This is more than enough to rotate the rotary sleeve valve  360  to fully open or close flow to the removable nozzle  334 . Preferably, therefore, rotary sleeve valve  360  has a barrel top  367 , as shown in  FIG. 7 , which is exposed at the top  303  of nozzle housing assembly  302  to directly indicate the position of flow shut off valve  360 , i.e. whether the valve is open or closed or at a position in-between. 
         [0063]    A stream deflection lug  392  and a stream break-up lug  393  are shown in  FIG. 8  as elements attached to the rotatable nozzle retention and flow shut off control ring  375 . 
         [0064]    Teeth  376  around the inside diameter of control ring  375  may be omitted beyond a rotational position of the control ring  375  in the counter-clockwise direction, as shown in  FIG. 8 , for example, at which the flow shut off valve  360  is fully opened, and beyond the rotational position in the clockwise direction at which the flow shut off valve  360  is fully closed. This will allow the ring to continue to be rotated to the right (counter-clockwise) once the flow shut off valve  360  is fully opened to enable a full stream to flow to the nozzle, which thereby enables other functions to be associated with the control ring  375 , such as mounting the flow break-up lug  393  or flow deflection lug  392  on the control ring  50 . The additional functional features may then be rotated to intercept the flow stream from the nozzle  334  in the primary flow opening  341  to produce the desired stream modification results. 
         [0065]    Also, continued rotation of the nozzle retention and flow shut off control ring  375  to the right (counter-clockwise) beyond the fully opened position of valve  360  will bring recess  391  in the ring  375  into alignment with nozzle  334 . Since the gearing for closing the flow shut off valve  360  has been omitted for this portion of the control ring  375 , the valve  360  is still open such that when recess  391  is moved into alignment with nozzle  334 , the flow pressure can be used to blow the now unrestrained nozzle out of the nozzle housing  315  so that another nozzle configuration maybe installed. 
         [0066]    Upon rotating the control ring  375  back to the left (clockwise) so that teeth  376  around the inside surface of ring gear  375  again engages teeth  366  of operator screw  365 , flow shut off valve  360  will again be rotated towards the closed position. This arrangement is configured so that when recess  390  is aligned with nozzle  334 , no flow or pressure is present in outlet passage  333  in the nozzle housing so that nozzle  334  may be removed for cleaning or substitution with a different nozzle, for example. 
         [0067]    After insertion of a new nozzle or re-insertion of the one removed, control ring  375  may be again rotated to the right (counter-clockwise) in which nozzle  334  is retained in the nozzle housing  315  by edge  380  of the ring  375 , such as the position shown in  FIG. 8 , wherein continued rotation of ring  375  will re-open flow shut valve  360  by aligning flow opening  361  in the valve  360  sleeve with flow passage  333  in the nozzle housing  315 . 
         [0068]    As shown in  FIGS. 7 and 8 , the removable nozzle  334  preferably includes an alignment and removal lug  395  at the bottom of the nozzle  334 . A recess  396  with sloped sides is formed in the nozzle housing  315  to cause nozzle  334  to be properly set and in the same position each time a nozzle is just installed into the nozzle housing side passage  333 . Also, a tool may be inserted into recess  396  behind the alignment and retention lug  395  to manually pry or pull the nozzle  334  out from the nozzle housing  315  when the nozzle is not retained by the ring  375 . As previously described, the nozzle  334  may be blown out with the ring  375  positioned with recess  391  aligned with the nozzle, if desired. 
         [0069]    Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. For example, although the present invention is described above as being preferably used in rotary driven sprinkler, it is noted that the present invention may also be useful in stationary sprinklers or sprinklers having a non-rotational spray pattern. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims.