This invention relates generally to improvements in irrigation sprinklers of the so-called micro-stream type having a rotatably driven vaned deflector for sweeping a plurality of relatively small water streams over a surrounding terrain area to irrigate adjacent vegetation. More specifically, this invention relates to an improved rotating stream sprinkler having a turbine driven gear drive arrangement for regulating the rotational speed of the vaned deflector to a controlled and relatively slow rate for sweeping and distributing the water streams relatively slowly over the adjacent landscape.
Rotating stream sprinklers, sometimes referred to as micro-stream sprinklers, are well known in the art of the type for producing a plurality of relatively small outwardly projected water streams swept over surrounding terrain for landscape irrigation. In one common form, one or more jets of water are directed upwardly against a rotatable vaned deflector which has a vaned lower surface defining an array of relatively small flow channels extending upwardly and turning radially outwardly with a spiral component of direction. The water jet or jets impinge upon this array of vanes to fill the curved flow channels and to impart a rotary drive torque for rotatably driving the deflector. At the same time, the water is guided by the curved flow channels for projection generally radially outwardly from the sprinkler in the form of a plurality of relatively small water streams to irrigate adjacent vegetation. As the deflector is rotatably driven, these small water streams are swept over the surrounding terrain area, with a range of throw depending in part on the channel configuration. Such rotating stream sprinklers have been designed for irrigating a surrounding terrain area of predetermined pattern, such as a full circle, half-circle, or quarter-circle pattern. For examples of such rotating stream sprinklers, see U.S. Pat. Nos. 4,660,766; 4,796,811; 4,815,662; 4,971,250; 4,986,474; Re. 33,823; U.S. Pat. Nos. 5,288,022; 5,058,806; 5,845,849; and 6,244,521.
In rotating stream sprinklers of this general type, it is desirable to control or regulate the rotational speed of the vaned deflector and thereby also regulate the speed at which the small water streams are swept over the surrounding terrain. In this regard, in the absence of speed control or brake means, the vaned deflector can be rotatably driven at an excessive speed up to and exceeding 1,000 rpm, resulting in rapid sprinkler wear and distorted water stream delivery patterns with reduced projected range. A relatively slow deflector rotational speed on the order of about 4-20 rpm is desired to achieve extended sprinkler service life while producing substantially uniform and consistent water stream delivery patterns. Toward this end, a variety of fluid brake devices have been developed wherein a rotor element carried by the vaned deflector is rotatably driven within a closed chamber containing a viscous fluid. In such designs, the viscous fluid applies a substantial drag to rotor element rotation which significantly reduces the rotational speed of the vaned deflector during sprinkler operation.
While such fluid brake devices are effective to prevent deflector rotation at excessive speeds, the actual rotational speed of the deflector inherently and significantly varies as a function of changes in water pressure and flow rate through the sprinkler. Since these parameters can vary during any given period or cycle of sprinkler operation, corresponding changes or fluctuations in the water stream delivery patterns can and do occur to result in inconsistent and sometimes inadequate irrigation of adjacent vegetation. In addition, such fluid brake concepts require the use and effective sealed containment of a viscous fluid such as a silicon-based oil or the like, which undesirably increases the overall complexity and cost of the irrigation sprinkler.
There exists, therefore, a need for further improvements in and to rotating stream sprinklers of the vaned deflector type for sweeping a plurality of relatively small water streams over a surrounding terrain area, particularly with respect to rotatably driving the vaned deflector at a controlled and relatively slow rotational speed to achieve improved and consistent water distribution with a substantially maximized the range of the outwardly projected water streams. The present invention fulfills these needs and provides further related advantages.
In accordance with the invention, a rotating stream sprinkler is provided of the type having a spiral vaned deflector for rotatably sweeping and distributing a plurality of relatively small outwardly projected water streams swept over a surrounding terrain area to irrigate adjacent vegetation. The sprinkler includes a turbine driven speed governor having meshed reduction gear components for regulating and limiting the speed of the deflector to a relatively slow rate of rotation which is approximately constant throughout a range of normal water supply pressures and flow rates.
The rotating stream sprinkler comprises the vaned deflector having an underside surface defined by an array of spiral vanes with generally vertically oriented upstream ends which spiral or curve and merge smoothly with generally radially outwardly extending and relatively straight downstream ends having a selected angle of inclination. These spiral vanes cooperatively define a corresponding array of intervening, relatively small flow channels of corresponding configuration. One or more upwardly directed water jets impinges upon the spiral vanes and are subdivided thereby into the plurality of relatively small water streams flowing through said channels. These water streams impart a rotational drive torque to the deflector and are then projected generally radially outwardly therefrom. As the deflector is rotated, these relatively small water streams are swept over the surrounding terrain area.
The turbine driven speed governor, in the preferred form, comprises a turbine rotatably driven at a relatively high rate of speed by water under pressure supplied to the sprinkler. The turbine rotatably drives an orbiter having a first or reaction gear meshed with a stator gear having a different number of gear teeth, and a second or drive gear meshed with a driven gear rotatably carried with the deflector and also having a different number of gear teeth. The orbiter is driven on an eccentric axis and reacts against the stator gear for rotatably driving the driven gear and deflector with a substantial speed reduction, thereby sweeping and distributing the projected water streams over the adjacent landscape at a regulated and relatively slow rate of speed with a substantially maximum projected range.
The rotating stream sprinkler further includes a flow rate adjustment assembly for selectively varying the rate of water inflow to the sprinkler to correspondingly permit selection of the projected range of the irrigation water streams. This flow rate adjustment assembly includes a rotatable adjustment screw carrying an axially translatable nut for bearing against a compressible restrictor element. Rotation of the adjustment screw selectively positions the nut in variable bearing engagement against the restrictor element for varying the cross sectional area of one or more inflow ports for water flow to the turbine and vaned deflector. The deflector can be axially shifted or depressed to engage a tool tip on a turbine shaft with the adjustment nut, and also to disengage the stator gear from a stator key to uncouple the deflector from the reduction gear components. In this depressed position, the deflector can be rotated for rotating the adjustment screw.
Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
The accompanying drawings illustrate the invention. In such drawings:
As shown in the exemplary drawings, a rotating stream sprinkler referred to generally in
The rotating stream sprinkler 10 of the present invention generally comprises a compact sprinkler nozzle unit or head having a base 20 adapted for convenient thread-on mounting or the like onto the upper end of a stationary or pop-up tubular riser 22(FIGS. 1-2). In general terms, the deflector 12 is rotatably supported on the base 20 and includes an underside surface defining an array of spiral vanes 24 (
More particularly, as shown in
A filter unit 44 having an upwardly open and generally cup-shaped configuration is mounted at the underside of the sprinkler base 20. In one form, this filter unit 44 includes an outwardly radiating upper flange 46 having a size and shape for press-fit or snap-fit reception into the underside of the base 20, as by snap-fit connection with an inwardly radiating shoulder 48 (
The turbine 16 is mounted at a lower end of the drive shaft 26 extending downwardly through a central aperture formed in the pattern plate 38. This drive shaft 26 is rotatably carried within a tubular bearing sleeve 56, a lower end of which extends downwardly through the pattern plate 38 as by press-fit or snap-fit reception therethrough and terminates in a lower end captured by a shaft seal 58. The turbine 16 is mounted onto the drive shaft 26 as by press-fit to snap-fit mounting thereon, to position the turbine within an upper region of the filer unit 44 generally surrounded by the imperforate upper wall segment 50 and in the path of upward water flow to the sprinkler 10, when the riser 22 is connected to a supply of water under pressure. A swirl plate 60 is also positioned within the substantially ixnperforate wall segment 50 of the filter unit 44, at an upstream location relative to the turbine 16, and includes an annular array of angularly oriented swirl ports 62 (shown best in
The drive shaft 26 and the associated bearing sleeve 56 project upwardly from the pattern plate 38, and through a central bore 66 (
The deflector 12, which also may be conveniently formed from lightweight molded plastic, incorporates the array of vanes 24 formed on an underside surface thereof. This array of vanes is disposed, as previously described, for engagement by the jet or jets of water flowing upwardly from the pattern plate 38, in accordance with the number and configuration of jet ports 42 formed in the pattern plate. These vanes 24 (shown best in
An upper end of the drive shaft 26 projects a short distance above the stator key 72 at the upper end of the bearing sleeve 56, and terminates in an upwardly projecting drive pin 74 disposed off-axis relative to a rotational axis of the drive shaft. This drive pin 74 is seated as by a slip-fit connection within a central port 76 formed in the orbitor 28. As viewed best in
The first or lower ring gear 78 on the orbiter 28 comprises a reaction gear supported by the drive pin 74 in an off-axis position meshed at one side along a line of contact with the stator gear 30. In this regard, the stator gear 30 comprises a diametrically larger female ring gear formed on a disk-shaped stator member 84 carried by the upper end of the bearing sleeve 56 and including a hub recess 86 of noncircular shape for normally receiving the stator key 72 of mating configuration. Accordingly, during normal sprinkler operation, the stator key 72 on the nonrotating bearing sleeve 56 interengages with the stator member 84 by means of the hub recess 86 to lock the stator member 84 and the associated stator gear 82 thereon against rotation.
The second or upper ring gear 80 on the orbiter 28 comprises a drive gear supported by the drive pin 74 in an off-axis position meshed at one side along a line of contact with the driven gear 32 for rotatably driving and regulating the rotational speed of the deflector 12. More specifically, the driven gear 32 also comprises a comparatively larger diameter female ring gear formed on a cap plate 88 having a size and shape for mounting onto and for rotation with the deflector 12. As shown, the illustrative cap plate 88 is designed for press-fit or other suitable attachment of the female driven gear 32 into an open upper end of a cylindrical wall 90 formed on the deflector 12 and upstanding from the periphery of the spiral vane array 24. Accordingly, the cap plate 88 is connected to and rotatable with the deflector 12. In addition, the cap plate 88 cooperates with the deflector 12 including the outer cylindrical wall 90 thereof to define a substantially enclosed chamber 92 within which the above described speed reduction gear components are protectively mounted.
In the preferred form, and in accordance with one primary aspect of the invention, the reaction and drive gears 78, 80 on the orbiter 28 are coaxial and have a generally or substantially common diametric size somewhat less that the stator and driven gears 30, 32 which also are coaxial and have generally or substantially common diametric size. Accordingly, the reaction and drive gears 78, 80 mesh with their respective stator and driven gears 30, 32 along a generally common or directly overlying orbital or radial line of contact. In addition, the number of gear teeth on each of the reaction and drive gears 78, 80 is different from the number of gear teeth on the stator and driven gears 30, 32 meshed respectively therewith to achieve a substantial speed reduction ratio in the drive speed of the cap plate 88 and deflector 12 relative to the drive shaft 54. For example, in one working embodiment of the invention, the reaction gear 78 on the orbiter 28 includes 31 gear teeth for meshed engagement with the stator gear 30 which has 32 gear teeth. In turn, the drive gear 80 on the orbiter 28 includes 32 gear teeth for meshed engagement with the driven gear 32 which has 33 gear teeth. In this particular geometry, this results in a speed ratio reduction of 32 between pair of meshed gears 78, 30 and 80, 32 for a total gear train speed reduction of 322, or 1,024.
During normal sprinkler operation, water under pressure is supplied via the riser 22 to the swirl plate 60 for passage through the swirl ports 62 therein to rotatably drive the turbine 16. This water flow axially passes the turbine 16 and proceed further upwardly through the jet ports 42 in the pattern plate 38 to impinge upon the array of vanes 24, thereby imparting a rotary drive torque to the deflector 12 as previously described. In addition, the water flow is subdivided by the vanes 24 into the plurality of relatively small water streams 14 for outwardly projection from the sprinkler.
The thus-driven turbine 16 rotatably drives the drive shaft 26 at a relatively high speed, for correspondingly rotating the drive pin 74 with an eccentric or off-axis rotary motion. The drive pin 74 imparts this off-axis or eccentric motion to the orbiter 28, causing the reaction and drive gears 78, 80 thereon to rotate slowly about a central axis of the drive shaft 26. In the course of such orbital motion, the reaction gear 78 reacts against the nonrotational stator gear 30, while the drive gear 80 rotatably drives the driven gear 32 at a slow rotational speed reflective of the total gear train speed reduction, e.g., a speed reduction of 1,024 in the foregoing example. Thus, the rotational speed of the cap plate 88 and the deflector 12 attached thereto is effectively regulated or limited by the turbine driven speed governor of the present invention at a relatively slow rate for slowly sweeping the projected water streams 14 over the surrounding terrain area. Importantly, the turbine 16 and speed reduction gear train 18 are designed to provided a deflector rotational speed in the range of about 4-20 rpm during sprinkler operation at normal water supply pressures and flow rates. Due to the large speed reduction ratio provided by the gear train 18, the rotational speed of the deflector 12 remains approximately constant despite variations in water supply pressure and flow rate with normal operation ranges.
A flow rate adjustment assembly 93 (FIGS. 3 and 11-12) may be provided for selectively setting the water flow rate through the sprinkler 10, for purposes of regulating the range of throw of the projected water streams 14. As shown (FIG. 3), this flow rate adjustment assembly 93 is mounted within the filter unit 44 at an upstream location relative to the swirl plate 60. Conveniently, the flow rate adjustment assembly 93 is adapted for variable setting by means of a screwdriver 94 (
The illustrative flow rate adjustment assembly 93 includes an adjustment screw 96 having a head 97 rotatably carried and axially retained by a cylindrical hub 98 of the swirl plate 60 (
A resilient flow rate restrictor element 108 is captured between the flow rate adjustment nut 102 and a support disk 110 seated axially against a backstop flange 112 formed on the screw head 97 (FIGS. 3 and 12). In addition, this support disk 110 may also include a pair of outwardly radiating ears 114 (shown best in
However, the flow rate of water through these channels 118, 120 can be selectively throttled or reduced by rotating the adjustment screw 96 in a direction translating the adjustment nut 102 in an upward direction to compress the restrictor element 108. Such adjustment is illustrated in
The head 97 of the adjustment screw 96 includes an upwardly presented slotted recess 125 (
More particularly, to adjust the water flow rate through the sprinkler 10 and thereby select the projected range of the water streams 14, the screwdriver or other suitable tool 94 (
In this downwardly shifted position with the stator member 84 free to rotate, rotatable displacement of the tool 94 is effective to rotate the deflector 12 and the gear train components to correspondingly rotate the drive shaft 26 is either direction. This rotational displacement is transmitted via the drive shaft 26 directly to the adjustment screw 96 for variably setting the adjustment nut 102 compressively against the restrictor element 108, as previously described, to adjust water flow rate to the swirl plate 60 and other operating components of the sprinkler. Importantly, the large speed ratio reduction provided by the gear train 18 effectively locks the cap plate 88 and deflector 12 with the gear train for positive rotary displacement of the drive shaft 26 during this adjustment step. Upon release of the adjustment tool 94 from the cap plate 88, and subsequent supply of water under pressure to the sprinkler 10, the upward force of the water jet or jets applied to the vaned underside of the deflector 12 functions to assure return displacement of the downwardly shifted components back to a normal operating position with the tool tip 126 on the drive shaft 26 spaced above and disengaged from the adjustment screw head 97 (as viewed in FIG. 3).
A variety of further modifications and improvements in and to the rotating stream sprinkler of the present invention will be apparent to those persons skilled in the art. Accordingly, no limitation on the invention is intended by way of the foregoing description and accompanying drawings, except as set forth in the appended claims.
Number | Name | Date | Kind |
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3854664 | Hunter | Dec 1974 | A |
4131234 | Pescetto | Dec 1978 | A |
Number | Date | Country | |
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20040195360 A1 | Oct 2004 | US |