1. Technical Field of the Invention
This invention relates generally to underground irrigation systems that include a plurality of pop-up-type sprinklers connected to an irrigation source pipeline, and more particularly, to shipping or flush caps for such sprinklers.
2. Related Art
Manufacturers of turf irrigation systems often supply the sprinklers with flush caps to cover the opening of the spray heads instead of a nozzle which will be used for normal operation. During installation, a shallow trench is dug in the desired layout, and the network of irrigation supply piping is laid out in the trench. The spray heads are then attached to the piping with the caps still attached, the water supply is connected, and the trench is covered over.
Once this has been done, the piping and spray heads must be flushed before the spray nozzles are installed to remove dirt and debris which accumulated in the system during installation, or the spray nozzles may become unobstructed when the system is placed in operation. This is accomplished by turning on the irrigation system and allowing a high pressure, high velocity flow through the system to “blow out” the dirt and debris, generally through side openings provided in the flush caps. In this flushing process, all of the spray heads along the irrigation path are essentially “blown out” at the same time (once the water flow reaches each respective sprinkler head), and then are closed at the same time, when the water supply is turned off.
Conventional flush caps include some type of mechanism which closes the spray head outlet opening when the water is turned off to prevent debris from reentering the spray head. After the pipes and spray heads have been flushed in a conventional sprinkler system, and the irrigation source has been turned off, the flush caps are removed from the spray heads in preparation for installation of the nozzles. When the spray heads are mounted on risers which are lifted by water pressure during operation, the conventional flush caps are typically equipped with a lift ring or other gripping means to facilitate lifting the riser.
To a greater or lesser degree, conventional flush caps suffer from certain disadvantages. For one thing, it is difficult to reliably seal the flush openings after the flushing process is completed. As a result, there is a risk of debris re-entering the spray heads, particularly, since the flush water usually pools around the spray heads. Providing a reliable closure often entails increased cost and complexity in an item which is generally not reusable.
Another problem is that conventional flush caps lack a way to selectively close an individual flush cap at a particular location in the system when further flushing of the spray head at that location is not needed, but other spray heads require further flushing. This results in unnecessary flooding around the spray heads which are already cleared, and prevents direction of extra water to the spray heads which do require further cleaning.
Thus a need clearly exists for further improvement in what, on its face, would seem to be a relatively simple, but widely used device.
The present invention seeks to satisfy this need by providing a flush cap assembly which includes a mechanism to shut off the water to individual spray heads and to reliably prevent backflow of debris through the shut off flush cap, as well as a method of preparing a sprinkler system for operation using such a flush cap assembly.
The device is comprised of a body portion which is constructed for removable attachment to the spray head, and a cap rotatably mounted on the body portion to open and close a flow passage through which the spray head and piping can be flushed of dirt and debris. The method of use involves providing each of the spray heads with a flush cap assembly as described above, installing the system, opening the flow passages for all the spray heads, turning on the water supply, selectively closing individual flush caps for portions of the system which have been sufficiently flushed, thereby directing additional water to portions of the system still requiring it, thereafter shutting down the system, and replacing the flush caps with spray nozzles.
Flush caps according to the invention provide improved functionality without adding significant cost, and the associated method permits more efficient, and, in some instances, faster preparation of the system for use.
The invention has several specific advantages over conventional flush caps. First, the shut off mechanism according to the invention allows the installer to shut off each spray head after sufficient water has flowed through that respective spray head. By enabling the installer to selectively stop the water flow through individual spray heads, further flushing of other spray heads can continue to be flushed without further flooding around the spray heads that have been shut off.
A second advantage provided by the invention is that when the installer shuts off selected spray heads, water flow to the other spray heads increases, which results in an increased flow rate of water through the other spray heads to thereby flush the system more effectively.
Referring first to
As best seen in
Body 12 also includes an upper portion 27 having a circumferentially extending opening 26 adapted to be aligned with opening 22 in cap 14 to allow water to exit from the spray head during the flushing operation. As described below, cap 14 is rotatable between such an aligned open position, and a closed position in which sleeve 20 blocks opening 26 to prevent water flow out of the spray head. A circumferential groove 28 encircling the body 12 engages with a retaining flange 30 extending radially inward from the bottom of sleeve 20 to guide the rotation of cap 14 relative to body 12, and to prevent cap 14 from being separated from body 12 by the force of the water during the flushing operation, but any other suitable or desired retaining means may be employed instead.
Axially below groove 28 is a stepped shoulder 31 extending part way around body 12. One end of shoulder 31 is delimited by a rotational limit stop 34 best seen in
As best seen in
A second embodiment of the invention is shown in
Body portion 112 and cap portion 114 may be secured together, for example, by a downwardly depending central pin having a barbed lower end (not shown) adapted to be snap fitted into a central opening 130 in the top of body portion 112. Alternatively, a slot and rib arrangement as shown and described in connection with the first embodiment, or any other suitable or desired arrangement, can be employed.
As best seen in
When the opening 126 of the cap 114 is aligned with the opening 126 of body portion 112 as shown in
In another embodiment of the invention, the flush cap shut-off feature may be provided as a flap or a slider which can be manually locked or released with respect to an opening on the body. In that event, the cap and body portions do not need to be movable relative to each other. Other mechanisms for blocking the outlet opening of the body may be implemented within the principles and scope of the present invention, as will be appreciated by those skilled in the art.
While the invention has been described and illustrated with reference to specific exemplary embodiments, it should be understood that many other modifications and substitutions could be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be considered as limited by the foregoing description, but is to be given the full scope permitted by the appended claims.
This application is based on and claims priority to U.S. Provisional Application 60/568,316, filed May 6, 2004, the entire disclosure of which is incorporated herein by reference.
Number | Date | Country | |
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60568316 | May 2004 | US |