Patent Publication Number: US-11045823-B2

Title: Rotary nozzle sprinkler with orbital diffuser

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is the U.S. national phase of International Application No. PCT/US2017/060593 filed Nov. 8, 2017 which designated the U.S. and claims priority to U.S. Provisional Patent Application No. 62/420,216 filed Nov. 10, 2016, the entire contents of each of which are hereby incorporated by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     (Not Applicable) 
     BACKGROUND 
     The invention relates to a rotary nozzle sprinkler and, more particularly, to a rotary nozzle sprinkler with an extended throw radius and a low-cost construction that provides low friction axial load support, braking action, intermittent stream diffusion and clocking of struts. 
     In some existing designs, a water stream flows through a nozzle and emits to atmosphere axially, and in a high velocity state, the water stream is deflected by a downstream deflector (60° or more) to arrive at a desired trajectory. A downstream deflector utilizes a portion of the energy in the water stream, and as such, the throw radius of the water stream can be limited. An example of a prior art sprinkler of this type is described in U.S. Pat. No. 7,395,977. 
     BRIEF SUMMARY 
     It would be desirable to design a rotary nozzle sprinkler with an increased throw radius that overcomes the drawbacks with existing designs. 
     In some embodiments, the rotary nozzle sprinkler of the described embodiments turns the water upstream of the nozzle when the water is in a much lower velocity state (as compared to the prior art devices). As such, there is less energy lost in the turn, and more energy is in the stream when it shoots radially away from the sprinkler. As a consequence, the sprinkler of the described embodiments will have a greater throw radius than what is possible with existing designs. The design also facilitates the ability to achieve good stream integrity, which also helps the throw radius. 
     In an exemplary embodiment, a rotary nozzle sprinkler includes a base assembly with a bearing, a stem mounted rotatably in the bearing, an elbow coupled at a proximal end to and rotatable with the stem and including an elbow bend, a nozzle secured to a distal end of the elbow, and a diffuser assembly including a brake mechanism cooperable with the elbow. The elbow bend may be a transverse offset bend. The rotary nozzle sprinkler may further include a cage assembly extending between the diffuser assembly and the base assembly, where the cage assembly is configured to clock around the base assembly with rotation of the elbow. In this context, the cage assembly may include diffuser struts coupled with the diffuser assembly and cage struts coupled with the diffuser struts. 
     The elbow and stem rotate around an elbow axis of rotation, and the rotary nozzle sprinkler may further include a brake shaft connected between the elbow and the brake mechanism. The brake shaft may have a brake shaft rotation axis that is offset and/or tipped relative to the elbow axis of rotation. The cage assembly may be aligned with the brake shaft rotation axis and may be correspondingly tipped relative to the elbow axis of rotation such that rotation of the elbow effects orbital rotation of the brake shaft rotation axis and the cage assembly. The base assembly may be provided with base lugs, where the cage assembly includes cage teeth, and the base lugs may engage the cage teeth as the cage assembly clocks orbitally around the base assembly. In some embodiments, the rotary nozzle sprinkler is provided with one more of the cage teeth than the base lugs. 
     The diffuser assembly may include diffuser bumps positioned in a nozzle stream path of the nozzle, where the diffuser bumps clock around the base assembly with the cage assembly. 
     A brake shaft channel may be secured to the elbow, and the brake shaft may be secured at one end in the brake shaft channel. In this context, the brake mechanism may include a viscous brake, and the brake shaft may be secured at an opposite end to the viscous brake. 
     The base assembly may include a base securable to a source of water under pressure and having a bore in which the bearing may be disposed, where the rotary nozzle sprinkler may further include a seal disposed between the base and the bearing. A spring may be disposed between the base and the seal that urges the seal into engagement with the bearing. 
     In another exemplary embodiment, a rotary nozzle sprinkler includes a base assembly including a base having a bore therein and a bearing secured in the bore. An elbow assembly coupled with the base assembly includes an elbow connected for rotation relative to the bearing around an elbow axis of rotation. The elbow is provided with an elbow bend. A nozzle is secured to a distal end of the elbow, and a diffuser assembly including a brake mechanism is cooperable with the elbow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other aspects and advantages will be described in detail with reference to the accompanying drawings, in which: 
         FIG. 1  is a sectional view of the rotary nozzle sprinkler according to preferred embodiments; 
         FIG. 2  is an elevation view of the rotary nozzle sprinkler shown in  FIG. 1 ; 
         FIG. 3  illustrates a base of the base assembly; 
         FIG. 4  illustrates an elbow; 
         FIG. 5  illustrates a nozzle; 
         FIG. 6  is a close-up sectional view of the diffuser and brake assembly; 
         FIGS. 7 and 8  are an elevation view and a sectional view, respectively, of the sprinkler from an opposite side of  FIG. 1 ; and 
         FIG. 9  is an elevation view of the sprinkler from another perspective. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a sectional view of the rotary nozzle sprinkler according to preferred embodiments.  FIG. 2  is an elevation view of the sprinkler from the same angle. A base assembly  10  includes a base  12  with a threaded end as shown that may be connected to a supply line that in turn is connected to a source of water under pressure. A seal assembly coupled with the base  12  includes a seal  14  having an O-ring  16 . A bearing  18  is threaded into a bore in the base  12 , and a stem  20  is rotatably supported in the bearing  18 . The bearing  18 , stem  20  and seal  14  are mounted over a spring  22  that urges the seal  14  into engagement with the inlet face (or lower face) of the stem  20 .  FIGS. 7-9  show views of the sprinkler from different perspectives. 
     The base  12  includes a plurality of base lugs  24 . See  FIGS. 3, 7 and 9 . The base assembly  10  is cooperable with a cage assembly  26  including cage struts  28  connected between an upper portion/diffuser  30  and a lower portion  32  of the cage assembly  26 . The lower portion  32  of the cage assembly  26  includes cage teeth  34  that engage the base lugs  24  of the base assembly  10 . 
     As shown, an elbow  36  is secured by threads or the like over the stem  20 , and a nozzle  38  is secured to a downstream end of the elbow  36 . A close-up view of an exemplary elbow  36  is shown in  FIG. 4 , and a close-up view of an exemplary nozzle  38  is shown in  FIG. 5 . The elbow  36  includes an elbow bend, such as a transverse offset bend, so that a reactionary force from an emitting stream  50  creates rotational drive about a rotational axis of the elbow, which corresponds to a vertical axis of the base  12 . The term “transverse offset bend” refers to an elbow that is bent in at least two planes, being a bend forward or backward relative to a water flow direction (see  FIG. 1 ) and a lateral bend or bend to the side. The base  12  and the elbow  36  may be provided with flow straightening vanes so the emitting stream  50  can have maximum stream integrity and radius of throw. The stem  20  may be provided with bearing surfaces to resist the side thrust of the nozzle stream. The elbow  36  and stem  20  may constitute a nozzle assembly. The nozzle  38 , elbow  36  and stem  20  all rotate together. 
     The diffuser  30  includes a brake assembly  40  such as a viscous brake or the like.  FIG. 6  is a close-up sectional view of the diffuser  30  and brake assembly  40 . A brake shaft  42  is connected at one end to the elbow  36  via a suitable bore or channel  44 . Specifically, the brake shaft  42  may be provided with raised knurling on the outside diameter that press fits into the bore/channel  44 . The brake shaft  42  is connected at an opposite end to the brake assembly  40 . In an exemplary embodiment, an impeller or the like is secured to the opposite end of the brake shaft  42  and is immersed in a viscous fluid. The brake assembly  40  serves to slow rotation of the elbow  36  to counteract the reactionary force on the elbow  36  by the emitting stream  50 . Without the brake assembly  40 , the nozzle  38 , elbow  36  and stem  20  would rotate at a high whirling speed. In some embodiments, the brake assembly  40  slows the rotation to somewhere in the range of 0.25-20 RPM, depending on the application. 
     The diffuser  30  includes diffuser struts  46  connected with the cage struts  28  via suitable connectors  47  and a plurality of diffuser bumps  48  spaced around an outer periphery of the diffuser  30 . As the nozzle  38 , elbow  36  and stem  20  rotate by action of the reactionary force on the elbow  36  by the emitting stream  50 , the emitting stream  50  intermittently impacts the diffuser bumps  48 , which serve to diffuse the stream emitted from the nozzle  38  to provide better coverage of the area being irrigated. 
     As shown in  FIGS. 1, 2, 6 and 7 , the diffuser  30  and cage assembly  26  are tipped at an angle such that several of the cage teeth  34  on one side of lower portion  32  are engaged with corresponding ones of the base lugs  24 . The axis of the brake shaft  42  is offset and/or tipped relative to the elbow axis of rotation. Rotation of the elbow  36  thus causes the brake axis to rotate in an orbital manner, which drives the diffuser  30  and cage assembly  26  in an orbital manner. In some embodiments, the sprinkler is provided with one more cage tooth  34  than the number of base lugs  24  that mesh with the cage teeth  34  on the one side. As a consequence, the diffuser struts  46  and diffuser bumps  48  clock slowly around. Clocking of the struts is helpful to prevent dry spokes in the water pattern. Clocking of the diffuser bumps is helpful to apply diffusion to all sectors of the water pattern. In an exemplary embodiment, the cage has twenty-eight teeth, and the base has twenty-seven lugs. The contact between mating faces of the base  12  and cage assembly  26  may be a rolling type contact so the upward thrust of the water pressure is resisted in a very low friction, low wear manner. 
     The design may also be adapted for use on a drop tube, for example, associated with a center pivot irrigation system. 
     In use, as water under pressure flows through the base  12  into the elbow  36 , the water impacts the elbow bend, and a reactionary force from the stream  50  creates rotational drive about the rotational axis of the elbow  36 . As the elbow  36  rotates about the elbow rotational axis, the tipped diffuser  30 , cage assembly  26  and brake shaft  42  rotate in an orbital manner, and the cage assembly  26  clocks around the base  12 . Clocking of the cage assembly  26  prevents spoking of the water pattern that could result from impacting static struts  28 ,  46  and also serves to displace the diffuser bumps  48 . Since the nozzle  38  is downstream of the elbow  36 , the stream is turned when the water is in a much lower velocity state. As such, there is less energy lost in the turn, and more energy is in the stream when it shoots radially away from the sprinkler. As a consequence, the sprinkler of the described embodiments can achieve a greater throw radius than what is possible with existing designs. 
     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.