Patent Application
20140110501
The present invention relates in general to a rotary distributor head for a sprinkler.
In sprinkler irrigation systems, water is received under pressure and is introduced into a main water supply pipe which is connected with one or more distributing pipes forming a fluid conduit. The irrigation system typically includes a plurality of discharge irrigation sprinkler heads to distribute water uniformly over a surrounding area. The sprinkler heads may be of the rotatably driven deflector type where a water stream is directed against the deflector, which drives the deflector using a series of channels that turn outwardly. In operation, the water stream impinges on the surface of the deflector and fills the channels to rotatably drive the deflector. As a consequence, water is thrown radially outward and swept out over the surrounding area.
A shortcoming of the rotatably driven deflector type head is the inability to control the rotational speed of the deflector. High rotational speeds result in less effective water distribution patterns and excessive sprinkler wear. Prior attempts to control the rotational speed include a fluid brake device which generally is a rotor element attached to the deflector and placed in a viscous fluid. The viscous fluid applies a drag on the rotor element to reduce the rotational speed of the deflector. However, the fluid brake devices do not consistently control the speed and vary with changes in water pressures and flow rates, which is prevalent in irrigations systems.
Another attempt to control the rotational speed is the use of braking channels on the deflector. One example is U.S. Pat. No. 7,240,860 to Griend, which describes a rotor plate that includes brake channels to slow the rotation of the deflector. A disadvantage of this design of including brake channels and distribution channels on the same deflector, is that the brake channels are curved opposite of the channels intended to distribute the water radially. Thus, each rotation of the deflector distributes less water, less uniformly, than a deflector with all channels on the deflector working together to distribute water.
Accordingly, what is needed in the art is a rotary distributor head for a sprinkler that controls the rotational speed while increasing the uniform wetted footprint of instantaneous impact under a range of operating pressures and flow rates.
However, in view of the prior art at the time the present invention was made, it was not obvious to those of ordinary skill in the pertinent art how the identified needs could be fulfilled.
In a particular embodiment, a rotary distributor head is disclosed. The head includes a first deflector pad, a plurality of distribution channels radially disposed on the first deflector pad configured to distribute a stream of water, and a second deflector pad axially aligned downstream of the first deflector pad. In addition, the head includes an orifice disposed on the first deflector pad configured to pass a portion of the stream of water through the first deflector pad to the second deflector pad. A plurality of grooves is radially disposed on the second deflector pad configured to cause the head to rotate when the water is flowing through the grooves.
In another particular embodiment, the head includes a stack of three or more deflector pads axially aligned, a plurality of distribution channels radially disposed on at least one deflector pad configured to distribute a stream of water, a plurality of spiral grooves disposed on at least one deflector pad configured to cause the head to rotate when the water is flowing through the grooves, and an orifice on each upstream deflector pad configured to pass a portion of the stream of water through to an adjacent downstream deflector pad.
One particular advantage provided by the embodiments of the rotary distributor head for a sprinkler is to control the rotational speed of the deflector pad while increasing an area of instantaneous impact and uniformity under a range of operating water pressures and flow rates.
Other aspects, advantages, and features of the present disclosure will become apparent after review of the entire application, including the following sections: Brief Description of the Drawings, Detailed Description, and the Claims.
Referring now to
A rotary distributor head of the sprinkler 100 includes a first deflector pad 102 and a second deflector pad 104 that are located downstream of the nozzle 108. The deflector pads 102, 104 are axially aligned to the nozzle 108 where a stream of water exits the nozzle 108 and impacts a top surface of the first deflector pad 102. The deflector pads 102, 104 (collectively, the “head”) are stacked together and rotate about a central shaft 110 or axis. The head provides for a relatively constant rotational speed through a range of flow rates at a given operating pressure.
In this particular embodiment, the head includes two deflector pads 102, 104. However, additional deflector pads may be used and stacked together as desired. Accordingly, the head has the ability to be adjusted to address each particular application to achieve the desired irrigation specifications by using different configurations and combinations of deflector pads with different characteristics. The first deflector pad 102 is configured to divide a water steam or jet received from the nozzle 108 into a plurality of water streams. As a portion of the water stream impinges the second deflector pad 104 causing rotation of the head, the plurality of water streams are swept over the surrounding area.
Turning now to
In accordance with further aspects of the head, a portion of the stream of water passes through an orifice 112 centrally disposed on the first deflector pad 102 to the downstream second deflector pad 104. A top surface of the first deflector pad 102 may be sloped outwards from the orifice 112 forming a truncated conical shape that is tapered to direct the water into the channels 114. A center divider 115 of the second deflector pad 104 divides the remaining water and directs the water into a plurality of spiral grooves 116, which distributes the remaining water radially outward. The spiral grooves 116 may be formed into an annular base 118 of the second deflector pad 104.
The plurality of spiral grooves 116 are radially disposed on the second deflector pad 104 and are configured to cause the deflector pads 102, 104 to rotate together when the water is flowing through the grooves 116. The spiral grooves 116 of the second deflector pad 104 are shaped in such a way to cause water exiting them to have a varying trajectory to direct the water radially outward from a center axis to generate a desired torque on the second deflector pad 104. The trajectory of each channel 114 of the first deflector 102 may be neutral, or opposite, to the trajectory of the plurality of grooves 116 of the second deflector pad 104. Accordingly, the channels 114 may be used, if necessary, to slow the rotational speed of the head. Thus, a combination of curvature of the channels 114 and the spiral grooves 116 may be used to produce a desired rotational speed under numerous different operating pressures, flow rates and conditions.
For example, the curvature of the channels 114 may be used as a braking mechanism to slow down the rotation of the head by having the curvature of the channels 114 in an opposing direction to that of the spiral grooves 116 of the downstream second deflector pad 104. Thus, the torque created by the spiral grooves 116 to rotate the head in a first direction, is offset in part by the channels 114 producing a torque in an opposing direction.
In addition, the size of the orifice 112 is such that the volume of water impinging on the second deflector pad 104 may eliminate the need for any braking altogether. In operation, the orifice 112 limits the amount of water impinging the second deflector pad 104 to maintain the rotation at a relatively constant speed over a range of flow rates at a given operating pressure. This ability to control the amount of water impinging the second deflector pad 104 and spiral grooves 116 that are driving the rotation of the head represents an advance over existing rotor plate designs that include braking channels and drive channels on the same rotor plate. In addition, a larger surface area is available to place more channels on the deflector pads to allow for greater control and freedom of where the water is distributed over a given area.
A connector is used to stack together the first deflector pad 102 and the second deflector pad 104. In a particular embodiment, the connector includes three struts 120 that extend downstream from an underside of the first deflector pad 102. Receptacles 122 are disposed on a top surface of the second deflector pad 104 that are adapted to slidingly engage and receive the respective struts 120 to secure the first pad 102 to the second pad 104 using a suitable snap-fit connection or the like. In this particular embodiment, the pads 102, 104 are separate elements, however, in another embodiment the pads 102, 104 are constructed as a single unit to form the head. One advantage of using a snap-fit connector as described herein is that the deflector pads are interchangeable.
As explained above, the rotary distributor head includes at least one deflector pad 102 configured to distribute a stream of water. A plurality of spiral grooves 116 disposed on the downstream second deflector pad 104 is configured to cause the head to rotate when the water is flowing through the grooves 116, and an orifice 112 on each upstream deflector pad 102 is configured to pass a portion of the stream of water through to the adjacent downstream second deflector pad 104. The plurality of distribution channels 114 is configured to distribute the water to a uniform area of instantaneous impact. In such an arrangement, the distribution channels 114 may have a neutral trajectory from a center to a periphery of a respective deflector pad 102. The deflector pads are interchangeable to adjust the range of the sprinkler 100 or the rotational speed of the head by using deflector pads with a different configuration of grooves, a size of the orifice, or any combination thereof. Further, the spiral grooves 116 may have one or more different curvatures to cause water exiting them to have trajectories that do not oppose one another.
The distribution channels 114 may be uniform on the deflector pad 102. The cross section areas of the distribution channels 114 may increase along their lengths to the periphery of the deflector pads 102. In addition, the distribution channels 114 may be evenly spaced about the deflector pad.
As illustrated in
Another particular embodiment of the rotary distributor head is illustrated in
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the disclosed embodiments. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the principles defined herein may be applied to other embodiments without departing from the scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope possible consistent with the principles and novel features as defined by the following claims.
