The present invention relates to sprinklers used to irrigate turf and landscaping.
Many geographic locations have dry spells and/or insufficient rainfall requiring turf and landscaping to be watered to maintain the proper health of the vegetation. Turf and landscaping are often watered utilizing an automatic irrigation system that includes a programmable controller that turns a plurality of valves ON and OFF to supply water through underground pipes connected to sprinklers. Golf courses, playing fields and other large areas typically require rotor-type sprinklers that eject a long stream of water via a single relatively large nozzle that oscillates through an adjustable arc. Smaller areas are often watered with spray heads or rotary stream sprinklers. Spray heads eject a fan-shaped pattern of water at a relatively high rate and much of this water often flows off the vegetation and/or blows away and is wasted. Rotary stream sprinklers eject relatively small individual streams of water and use less water than spray head sprinklers. In some cases drip nozzles are employed in residential and commercial irrigation systems for watering trees and shrubs, for example.
Sprinklers used to irrigate turf and landscaping are exposed to many forces and contaminants that can adversely impact the performance of the sprinklers and in some cases render them completely inoperable. Rotary stream sprinklers are especially venerable to impaired performance due to the ingress of dirt and grit and the build up of calcium deposits. Rotary stream sprinklers typically include a nozzle head or stream deflector having flutes formed on the underside thereof that receive water from orifices in a nozzle plate and channel streams of water radially outward onto the turf or landscaping. The flutes and orifices can become clogged with dirt and grit, particularly where the sprinkler nozzle retracts to the level of the ground. Over time, calcium and other mineral deposits can build up due to evaporation and constrict or obstruct the flutes and/or orifices, particularly when the orifices are very small as required to produce a rotary stream sprinkler with a very small flow rate. For example, a round orifice in the nozzle plate might be only 0.015 inches in diameter in order to provide a rotary stream sprinkler with a flow rate of four gallons per hour. Such a low volume rotary stream sprinkler would be particularly desirable because it could be substituted for a spray head and result in substantial water savings.
Rotary stream sprinklers either employ a reactionary drive or a gear reduction in order to slowly rotate the stream deflector to optimize the water distribution. When a reactionary drive is employed, the flutes are angled so that the water ejected by the stream deflector rotates the same. A viscous damper or friction brake must be used to slow the rotation of the stream deflector with angled flutes. In a rotary stream sprinkler with a reactionary drive, the stream deflector can pop-up from a protective outer cylindrical base when the water is turned ON, and retract into the protective outer base, thereby providing a degree of protection of the flutes and nozzle plate orifices from dirt, debris and mineral deposit build-up due to evaporation. However, pop-up operation of the stream deflector is not practical in a rotary stream sprinkler that employs a gear reduction for driving the stream deflector. Therefore it would be desirable to provide such a sprinkler with an alternate means of protecting its flutes and orifices from debris and mineral build-up due to evaporation.
In accordance with the present invention, a sprinkler includes a nozzle and a cover configured for enclosing the nozzle. A hydraulically actuated mechanism supports the cover above the nozzle for reciprocation relative to the nozzle between a lower closed position and a raised open position.
The entire disclosures of the following U.S. patents disclosing rotary stream sprinklers, which are all assigned to Hunter Industries, Inc., the assignee of the subject application, are hereby incorporated by reference: U.S. Pat. No. 4,842,201 granted Jun. 27, 1989 to Edwin J. Hunter entitled ROTARY STREAM SPRINKLER UNIT; U.S. Pat. No. 4,867,379 granted Sep. 19, 1989 to Edwin J. Hunter entitled ROTARY STREAM SPRINKLER UNIT; U.S. Pat. No. 4,898,332 granted Feb. 6, 1990 to Edwin J. Hunter et al. entitled ADJUSTABLE ROTARY STREAM SPRINKLER; U.S. Pat. No. 4,932,590 granted Jun. 12, 1990 to Edwin J. Hunter entitled ROTARY STREAM SPRINKLER UNIT WITH ROTOR DAMPING MEANS; U.S. Pat. No. 4,967,961 granted Nov. 6, 1990 to Edwin J. Hunter entitled ROTARY STREAM SPRINKLER UNIT; U.S. Pat. No. 4,971,250 granted Nov. 20, 1990 to Edwin J. Hunter entitled ROTARY STREAM SPRINKLER WITH ROTOR DAMPING MEANS, U.S. Pat. No. 5,058,806 granted Oct. 22, 1991 to Robert L. Rupar entitled STREAM PROPELLED ROTARY POP-UP SPRINKLER WITH ADJUSTABLE SPRINKLING PATTERN; U.S. Pat. No. 5,288,022 granted Feb. 22, 1994 to George L. Sesser entitled PART CIRCLE ROTATOR WITH IMPROVED NOZZLE ASSEMBLY; U.S. Pat. No. 6,244,521 granted Jun. 12, 2001 to George Sesser entitled MICRO-STREAM ROTATOR WITH ADJUSTMENT OF THROW RADIUS AND FLOW RATE; U.S. Pat. No. 6,499,672 granted Dec. 31, 2002 to George Sesser entitled MICRO-STREAM ROTATOR WITH ADJUSTMENT OF THROW RADIUS AND FLOW RATE; U.S. Pat. No. 6,651,905 granted Nov. 25, 2003 to George Sesser et al. entitled ADJUSTABLE ARC, ADJUSTABLE FLOW RATE SPRINKLER; U.S. Pat. No. 6,688,539 granted Feb. 10, 2004 to Loren Vander Griend entitled WATER DISTRIBUTION PLATE FOR ROTATING SPRINKLERS; U.S. Pat. No. 6,736,332 granted May 18, 2004 to George L. Sesser et al. entitled ADJUSTABLE ARC, ADJUSTABLE FLOW RATE SPRINKLER; U.S. Pat. No. 7,032,836 granted Apr. 25, 2006 to George Sesser et al. entitled ADJUSTABLE ARC, ADJUSTABLE FLOW RATE SPRINKLER; U.S. Pat. No. 7,159,795 granted Jan. 9, 2007 to George L. Sesser et al. entitled ADJUSTABLE ARC, ADJUSTABLE FLOW RATE SPRINKLER; and U.S. Pat. No. 7,322,533 granted Jan. 29, 2008 to Glendale Grizzle entitled ROTARY STREAM SPRINKLER WITH ADJUSTABLE DEFLECTOR RING. In addition, the entire disclosures of pending U.S. patent application Ser. No. 11/762,678 of Michael L. Clark filed Jun. 13, 2007 entitled “Gear Driven Sprinkler with Top Turbine,” and Pending U.S. patent application Ser. No. 11/928,579 of LaMonte D. Porter filed Oct. 30, 2007 entitled “Rotary Stream Sprinkler Nozzle with Offset Flutes,” both assigned to Hunter Industries, Inc. are hereby incorporated by reference.
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The rotary stream sprinkler 10 can have a very low rate of precipitation, e.g. approximately four gallons per hour or less, when the sprinkler 10 is coupled to a source of water pressurized between about 20 and 50 PSI. As illustrated in
The location of the turbine 18 at the top of the rotary stream sprinkler 10 above the planetary gear train reduction 20 substantially eliminates the pressure difference that would otherwise tend to cause dirt and other debris to enter the gear box 28 through a turbine shaft bearing conventionally located in the lower end of the gear box 28. The top placement of the turbine 18 also reduces adverse effects of water and air surges that could damage a turbine conventionally located at the lower inlet end of the device. Locating the turbine 18 at the top of the rotary stream sprinkler 10 also allows the turbine 18 to have a larger diameter which produces a larger drive force for the stream deflector 24. The additional water flow needed for large radius or arc of coverage does not have to flow around the turbine 18, thereby providing increased torque.
While the gear train reduction 20 has the configuration of a planetary gear drive, other forms of gear train reduction could also be used such as a staggered gear train reduction of the type illustrated in
A cylindrical housing 34 (
A screen 38 (
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The exploded views of
While I have described and illustrated an embodiment of a rotary stream sprinkler with a hydraulically actuated nozzle cover, it should be apparent to those skilled in the art that my invention can be modified in arrangement and detail. For example, the planetary gear reduction of sprinkler 10 can be operatively coupled in various different ways. For example, the gear box 28 could rotate and drive the stream deflector 24. Mechanisms can also be incorporated into the sprinkler 10 for adjusting the shape of coverage. It is not necessary to incorporate a means for biasing the cover 44 downward since it could fall downward under the force of gravity without a spring once the sprinkler 10 is de-pressurized. However, the biasing means enhances the integrity of the seal that prevents the ingress of debris and reduces the evaporation of residual water from the surfaces of the flutes 32 and the orifice 31 in the nozzle plate 30. The hydraulically actuated nozzle cover could also be incorporated into it other types of sprinklers besides gear driven rotary stream sprinklers, including rotary stream reaction drive sprinklers, spray nozzle type sprinklers, and gear-driven rotor-type sprinklers. Therefore, the protection afforded my invention should only be limited in accordance with the scope of the following claims.