1. Field of the Disclosure
The present disclosure relates to an apparatus and method for maintaining consistent rotational speed of a rotary nozzle sprinkler with viscous damping when the arc of coverage is adjusted resulting in varying water flow rates.
2. Related Art
Rotary sprinklers using viscous dampening have been in use in the irrigation industry for more than fifteen years. Viscous damping resistance is provided to apply a specific amount of friction to counter movement of a deflector of the rotary sprinkler when a force is applied to it. Viscous damping has several advantages over gear driven sprinklers or impact sprinklers. For example, viscous damped sprinklers have fewer moving parts and a longer life. One drawback of viscous damped sprinklers is the inability to control the speed of rotation over varying water flow and pressure ranges.
Today, in the sprinkler industry, there are several manufacturers of rotary nozzles. These rotary nozzles use viscous damping, which is known in the art, to limit the speed at which the sprinklers rotate. Viscous damping relies upon oils or greases to create friction to limit sprinkler rotation speeds. Viscous damped units, however, typically are unable to maintain a consistent rotational speed over a wide range of pressure and flow rates. Another problem may arise when a small arc of coverage is selected, where the viscous damped sprinkler will have a very low flow rate. The low flow rate may not provide enough kick, or rotational force, to rotate the deflector and the rotary nozzle will stop rotating or stall.
Water deflection at the discharge point is what typically determines the power and rotational speed. Viscous damped rotary nozzles utilize a deflector with multiple fixed angular slots, or channels, which discharge the water off the deflector in streams. As the water is discharged from the internal valve it strikes the deflector and force is exerted on the deflector supplying the power to rotate the deflector while the viscous oil limits the speed of the turning deflector. The limitation of the current designs on the market is that as the arc of coverage increased, the flow against the deflector increases to maintain matched precipitation. This results in an increase in the rotational speed of the deflector because there are more streams of water and more force exerted on the deflector. Currently, in the industry, contractors and consumers have to purchase rotary nozzles in fixed patterns 90, 180, 270, and 360 degrees or nozzles that have limited adjustable range. These units in order to maintain speed over different flow rates all have unique deflectors to compensate for the amount of water to control the speed. The limitation with these conventional units that are currently on the market is that if the flow or pressure is changed, the rotation speed of the sprinkler increases or decreases. That is, there is no mechanism to change or control the rotational speed. A few manufacturers offer adjustable units that are adjustable only through a limited range, not 80 to 360 degrees.
Accordingly, it would be desirable to provide a deflector of a rotary sprinkler that avoids these and other problems.
An objective of the present disclosure is to provide a means for increasing or decreasing the speed of rotation of a rotary nozzle sprinkler.
Another objective is to expand the operating pressure range of rotary nozzle sprinklers.
A rotating deflector for use with a rotary sprinkler in accordance with an embodiment of the present disclosure includes a conical body, a plurality of channels formed on a bottom surface of the conical body and extending from a center of the conical body outward toward an outer edge of the conical body, and a deflector ring rotatably mounted on the conical body such that the deflector ring rotates from a first position in which the deflector ring provides additional rotational force for rotation of the deflector and a second position in which the deflector ring provides substantially no rotational force for rotation of the deflector.
A rotary sprinkler assembly in accordance with an embodiment of the present disclosure includes a base configured to received water, a riser mounted in the base and movable from a down position to an up position in the base, and a rotary nozzle assembly provided at a top of the riser and configured to direct water that flows through the base and the riser outward around the rotary sprinkler assembly. The rotary nozzle assembly included a rotating deflector configured to deflect the water outward around the rotary sprinkler assembly. The rotating deflector includes a conical body, a plurality of channels formed on a bottom surface of the conical body and extending from a center of the conical body outward toward an outer edge of the conical body to direct water outward around the rotary sprinkler assembly, and a deflector ring rotatably mounted on the conical body such that the deflector ring rotates from a first position in which the deflector ring provides additional rotational force for rotation of the deflector and a second position in which the deflector ring provides substantially no rotational force for rotation of the deflector.
Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings.
The present disclosure provides a simple apparatus for maintaining consistent rotational speed of a rotary nozzle sprinkler with viscous damping when the arc of coverage is adjusted resulting in varying water flow rates. A benefit of this new design is that one adjustable arc rotary nozzle sprinkler can be used in the place of several different fixed arc units. The adjustable unit still maintains speed and uniformity across adjustment from 80 to 360 degrees. Rotation speed is important to maintaining uniform distribution and distance of throw. With the disclosed enhancement to an adjustable arc rotary sprinkler, one unit can replace what now takes three separate units to cover area from 80 to 360 degrees.
The present disclosure is related to controlling the rotational speed of viscous damped units over a wide operating flow range. Today in the industry, to deal with the speed control issues, most manufacturers build viscous damped sprinklers in fixed arcs of coverage changing the amount of water deflection to control the speed of the units.
This present disclosure specifically shows how a small ring 1 is added to the deflector which may be used to increase or decrease the amount of kick provided by water flow in a limited number of discharge streams of the deflector to increase the angular discharge for small arcs of coverage to have reliable rotation speeds.
More specifically,
A rotary nozzle assembly 12 is mounted on the top of the riser 4. The rotary nozzle assembly 12 of
In a preferred embodiment, the rotary nozzle assembly 12 includes a deflector 2 mounted on a shaft 13 that extends downward to a viscous braking assembly 11. The bottom end of the shaft 13 includes or is connected to a rotor 16. The bottom end of the shaft 13 and the rotor 16 are mounted in a fluid chamber 11 a of the end of the shaft 13. The fluid chamber 11a includes a viscous material such as oil or grease. The rotor 16 is sized such that there is a narrow clearance between the outer edge of the rotor and the inner surface of the sidewall of the chamber 11a. The deflector 2 is secured to the shaft 13 such that the shaft rotates with the deflector. The resistance of the viscous fluid in the chamber 11a against the rotation of rotor 16 limits the speed of rotation of the deflector 2.
The flow control ring 3 shown in
The deflector 2 further includes a stream deflector ring 1. In
The deflector ring 1 includes a plurality of downward extending ribs 1a that extend at an angle to the radial direction. That is, the ribs 1a extend outward away from the center of the deflector 2 at an angle to a radius of the deflector 2. Alternatively, the ribs 1a may simply be curved relative to a radius of the deflector 2. The ring 1 is rotatable with respect to the deflector 2 and the channels 16, 16′ formed therein, such that the ribs 1a may be moved between a first position and a second position. In the first position, illustrated in
In use, when the arc of coverage is relatively small and/or when the flow rate is reduced, the ring 1 is rotated to place the ribs 1a in the first position such that they impart additional rotational force to the deflector 2 to maintain relatively constant speed despite the reduced flow and contact of the water with the deflector 2. At higher flow rates and/or arcs of coverage, the ring 1 is rotated to move the ribs 1a into the second position since additional rotational force is unnecessary to maintain speed.
While five ribs 1a are illustrated in
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.
The present application claims benefit of and priority to U.S. Provisional Patent Application Ser. No. 61/552,153 filed Oct. 27, 2011 entitled VISCOUS DAMPED ROTARY NOZZLE SPEED CONTROL, the entire content of which is hereby incorporated by reference herein.
Number | Name | Date | Kind |
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4754925 | Rubinstein | Jul 1988 | A |
4944456 | Zakai | Jul 1990 | A |
4967961 | Hunter | Nov 1990 | A |
5718381 | Katzer et al. | Feb 1998 | A |
Number | Date | Country | |
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20130105596 A1 | May 2013 | US |
Number | Date | Country | |
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61552153 | Oct 2011 | US |