Patent Application
20130334340
This invention relates to irrigation sprinklers and, more particularly, to an irrigation sprinkler head or nozzle operative through an adjustable arc and with an adjustable flow rate.
Nozzles are commonly used for the irrigation of landscape and vegetation. In a typical irrigation system, various types of nozzles are used to distribute water over a desired area, including rotating stream type and fixed spray pattern type nozzles. One type of irrigation nozzle is the rotating deflector or so-called micro-stream type having a rotatable vaned deflector for producing a plurality of relatively small water streams swept over a surrounding terrain area to irrigate adjacent vegetation.
Rotating stream nozzles of the type having a rotatable vaned deflector for producing a plurality of relatively small outwardly projected water streams are known in the art. In such nozzles, one or more jets of water are generally directed upwardly against a rotatable deflector having 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 underside surface of the deflector to fill these curved channels and to rotatably drive the deflector. At the same time, the water is guided by the curved channels for projection outwardly from the nozzle in the form of a plurality of relatively small water streams to irrigate a surrounding area. As the deflector is rotatably driven by the impinging water, the water streams are swept over the surrounding terrain area, with the range of throw depending on the radius reduction of water through the nozzle, among other things.
In rotating stream nozzles and in other nozzles, it is desirable to control the arcuate area through which the nozzle distributes water. In this regard, it is desirable to use a nozzle that distributes water through a variable pattern, such as a full circle, half-circle, or some other arc portion of a circle, at the discretion of the user. Traditional variable arc nozzles suffer from limitations with respect to setting the water distribution arc. Some have used interchangeable pattern inserts to select from a limited number of water distribution arcs, such as quarter-circle or half-circle. Others have used punch-outs to select a fixed water distribution arc, but once a distribution arc was set by removing some of the punch-outs, the arc could not later be reduced. Many conventional nozzles have a fixed, dedicated construction that permits only a discrete number of arc patterns and prevents them from being adjusted to any arc pattern desired by the user.
Other conventional nozzle types allow a variable arc of coverage but only for a very limited arcuate range. Because of the limited adjustability of the water distribution arc, use of such conventional nozzles may result in overwatering or underwatering of surrounding terrain. This is especially true where multiple nozzles are used in a predetermined pattern to provide irrigation coverage over extended terrain. In such instances, given the limited flexibility in the types of water distribution arcs available, the use of multiple conventional nozzles often results in an overlap in the water distribution arcs or in insufficient coverage. Thus, certain portions of the terrain are overwatered, while other portions are not watered at all. Accordingly, there is a need for a variable arc nozzle that allows a user to set the water distribution arc along a substantial continuum of arcuate coverage, rather than several models that provide a limited arcuate range of coverage.
It is also desirable to control or regulate the throw radius of the water distributed to the surrounding terrain. In this regard, in the absence of a radius reduction device, the irrigation nozzle will have limited variability in the throw radius of water distributed from the nozzle, given relatively constant water pressure from a source. The inability to adjust the throw radius results both in the wasteful watering of terrain that does not require irrigation or insufficient watering of terrain that does require irrigation. A radius reduction device is desired to allow flexibility in water distribution and to allow control over the distance water is distributed from the nozzle, without varying the water pressure from the source. Some designs provide only limited adjustability and, therefore, allow only a limited range over which water may be distributed by the nozzle.
In addition, in previous designs, adjustment of the distribution arc has been regulated through the use of a hand tool, such as a screwdriver. The hand tool may be used to access a slot in the top of the nozzle cap, which is rotated to increase or decrease the length of the distribution arc. The slot is generally at one end of a shaft that rotates and causes an arc adjustment valve to open or close a desired amount. Users, however, may not have a hand tool readily available when they desire to make such adjustments. It would be therefore desirable to allow arc adjustment from the top of the nozzle without the need of a hand tool. It would also be desirable to allow the user to depress and rotate the top of the nozzle to directly actuate the arc adjustment valve, rather than through an intermediate rotating shaft.
Accordingly, a need exists for a truly variable arc nozzle that can be adjusted to a substantial range of water distribution arcs. In addition, a need exists to increase the adjustability of radius reduction and throw radius of an irrigation nozzle without varying the water pressure, particularly for rotating stream nozzles of the type for sweeping a plurality of relatively small water streams over a surrounding terrain area. Further, a need exists for a nozzle that allows a user to directly actuate an arc adjustment valve, rather than through a rotating shaft requiring a hand tool, and to adjust the throw radius by actuating or rotating an outer wall portion of the nozzle.
The arc adjustment and radius reduction features of the nozzle 1000 are similar to those described in U.S. patent application Ser. No. 12/952,369, which is assigned to the assignee of the present application and which application is incorporated herein by reference in its entirety. Further, some of the structural components of the nozzle 1000 are preferably similar to those described in U.S. patent application Ser. No. 12/952,369, and, as stated, the application is incorporated herein by reference in its entirety. Differences in the arc adjustment feature, radius reduction feature, and structural components are addressed below and with reference to the figures.
As described in more detail below, the nozzle 1000 allows a user to depress and rotate a deflector 1008 to directly actuate the arc adjustment valve 1002, i.e., to open and close the valve. The user depresses the deflector 1008 to directly engage and rotate one of the two nozzle body portions that forms the valve 1002 (valve sleeve 1004). The valve 1002 preferably operates through the use of two helical engagement surfaces that cam against one another to define an arcuate opening 1010. Although the nozzle 1000 preferably includes a shaft 1020, the user does not need to use a hand tool to effect rotation of the shaft 1020 to open and close the arc adjustment valve 1002. The shaft 1020 is not rotated to cause opening and closing of the valve 1002. Indeed, the shaft 1020 is preferably fixed against rotation, such as through use of splined engagement surfaces.
The nozzle 1000 also preferably uses a spring 1029 mounted to the shaft 1020 to energize and tighten the seal of the closed portion of the arc adjustment valve 1002. More specifically, the spring 1029 operates on the shaft 1020 to bias the first of the two nozzle body portions that forms the valve 1002 (valve sleeve 1004) downwardly against the second portion (nozzle cover 1006). In one preferred form, the shaft 1020 translates up and down a total distance corresponding to one helical pitch. The vertical position of the shaft 1020 depends on the orientation of the two helical engagement surfaces with respect to one another. By using a spring 1029 to maintain a forced engagement between valve sleeve 1004 and nozzle cover 1006, the nozzle 1000 provides a tight seal of the closed portion of the arc adjustment valve 1002, concentricity of the valve 1002, and a uniform jet of water directed through the valve 1002. In addition, mounting the spring 1029 at one end of the shaft 1020 results in a lower cost of assembly. Further, as described below, the spring 1029 also provides a tight seal of other portions of the nozzle body 1016, i.e., the nozzle cover 1006 and collar 1040.
As can be seen in
The rotatable deflector 1008 has an underside surface that is contoured to deliver a plurality of fluid streams generally radially outwardly therefrom through an arcuate span. As shown in
The variable arc capability of nozzle 1000 results from the interaction of two portions of the nozzle body 1016 (nozzle cover 1006 and valve sleeve 1004). More specifically, as can be seen in
As shown in
The arcuate span of the nozzle 1000 is determined by the relative positions of the internal helical surface 1005 of the nozzle cover 1006 and the complementary external helical surface 1003 of the valve sleeve 1004, which act together to form the arcuate opening 1010. The camming interaction of the valve sleeve 1004 with the nozzle cover 1006 forms the arcuate opening 1010, as shown in
In an initial lowermost position, the valve sleeve 1004 is at the lowest point of the helical turn on the nozzle cover 1006 and completely obstructs the flow path through the arcuate opening 1010. As the valve sleeve 1004 is rotated in the clockwise direction, however, the complementary external helical surface 1003 of the valve sleeve 1004 begins to traverse the helical turn on the internal surface 1005 of the nozzle cover 1006. As it begins to traverse the helical turn, a portion of the valve sleeve 1004 is spaced from the nozzle cover 1006 and a gap, or arcuate opening 1010, begins to form between the valve sleeve 1004 and the nozzle cover 1006. This gap, or arcuate opening 1010, provides part of the flow path for water flowing through the nozzle 1000. The angle of the arcuate opening 1010 increases as the valve sleeve 1004 is further rotated clockwise and the valve sleeve 1004 continues to traverse the helical turn.
When the valve sleeve 1004 is rotated counterclockwise, the angle of the arcuate opening 1010 is decreased. The complementary external helical surface 1003 of the valve sleeve 1004 traverses the helical turn in the opposite direction until it reaches the bottom of the helical turn. When the surface 1003 of the valve sleeve 1004 has traversed the helical turn completely, the arcuate opening 1010 is closed and the flow path through the nozzle 1000 is completely or almost completely obstructed. It should be evident that the direction of rotation of the valve sleeve 1004 for either opening or closing the arcuate opening 1010 can be easily reversed, i.e., from clockwise to counterclockwise or vice versa, such as by changing the thread orientation.
As shown in
As shown in
As can be seen in
In operation, a user may rotate the outer wall of the nozzle collar 1040 in a clockwise or counterclockwise direction. As shown in
Rotation in a counterclockwise direction results in axial movement of the throttle nut 1044 toward the inlet 1050. Continued rotation results in the throttle nut 1044 advancing to the valve seat 1048 formed at the inlet 1050 for blocking fluid flow. The dimensions of the radial tabs 1062 and 1064 of the throttle nut 1044 and the splined internal surface 132 of the nozzle collar 1040 are preferably selected to provide over-rotation protection. More specifically, the radial tabs 1062 and 1064 are sufficiently flexible such that they slip out of the splined recesses upon over-rotation. Once the inlet 1050 is blocked, further rotation of the nozzle collar 1040 causes slippage of the radial tabs 1062 and 1064, allowing the collar 1040 to continue to rotate without corresponding rotation of the throttle nut 1044, which might otherwise cause potential damage to sprinkler components.
Rotation in a clockwise direction causes the throttle nut 1044 to move axially away from the inlet 1050. Continued rotation allows an increasing amount of fluid flow through the inlet 1050, and the nozzle collar 1040 may be rotated to the desired amount of fluid flow. When the valve is open, fluid flows through the nozzle 1000 along the following flow path: through the inlet 1050, between the nozzle collar 1040 and the throttle nut 1044, between the ribs 1068 of the nozzle cover 1006, through the arcuate opening 1010 (if set to an angle greater than 0 degrees), upwardly along the upper cylindrical wall of the nozzle cover 1006, to the underside surface of the deflector 1008, and radially outwardly from the deflector 1008. As noted above, water flowing through the opening 1010 may not be adequate to impart sufficient force for desired rotation of the deflector 1008, when the opening 1010 is set at relatively low angles. It should be evident that the direction of rotation of the outer wall for axial movement of the throttle nut 1044 can be easily reversed, i.e., from clockwise to counterclockwise or vice versa.
As addressed above and shown in
In this preferred form, the structure of certain components has been tailored to reduce the variable effect of fluid pressure on the torque required to rotate the collar 1040 to actuate the flow rate adjustment valve (or radius reduction valve 1034). More specifically, as described in more detail below, the structure of the valve seat 1048, the nozzle cover 1006, and the nozzle collar 1040 allows a user to rotate the collar 1040 with an adjustment torque that is substantially independent of fluid pressure through the nozzle body 1016. The spring force is not directed axially against the nozzle collar 1040 but is instead directed axially against the nozzle cover 1006. Further, the frictional engagement between the nozzle collar 1040 and other components of the nozzle body 1016 has been reduced. Essentially, this structure reduces the torque required by the user to rotate the nozzle collar 1040 and to actuate the valve 1034, and in short, the valve 1034 is easier for a user to operate.
The radius reduction valve 1034 and certain components are shown in
As shown in
It is desirable to have the torque required for rotation of the nozzle collar 1040 to be relatively constant regardless of the flow rate through the nozzle body 1016. More specifically, it is desirable that the nozzle collar 1040 not be more difficult to rotate at high flow rates and long radiuses of throw. Further, it is desirable that the torque be less than about 3 inches-pound so that a user can easily rotate the collar 1040 (and thereby operate the valve 1034) with his or her fingers.
In designs where a spring directly engages the collar and urges it in an upward direction, there may be friction between the rotating collar and the static, non-rotating spring. Further, depending on the arrangement of the nozzle collar and the nozzle cover, it has been found that upward axial flow of the water may cause the collar to be urged upwardly against the cover. In turn, this may cause increased frictional engagement between the collar and the cover, thereby requiring greater torque for rotation of the collar. Thus, fluid flowing upward through the nozzle adds torque resistance to the radius reduction mechanism. In fact, it has been found that the spring load directed against the collar may be responsible for about 30% of the required adjusting torque from a user (about 20% due to friction between the spring and collar and about 10% due to friction between the collar and cover).
With respect to nozzle 1000, the valve seat 1048, the nozzle cover 1006, and the nozzle collar 1040 reduce the variable effect of fluid pressure on the required adjusting torque. More specifically, the structure reduces or eliminates engagement and the resulting friction between spring 1029 and collar 1040 and between collar 1040 and cover 1006. By reducing or eliminating this engagement, the required adjusting torque does not fluctuate depending on increases and decreases in fluid pressure, i.e., it is largely independent of fluid pressure.
As can be seen in
Thus, in this manner, the required adjustment torque is relatively constant and is reduced from what might otherwise be required, at high flow rates. In nozzle 1000, the required torque still needs to overcome friction arising from the compression at o-ring seals 1007 and needs to be sufficient to move the throttle nut 1044 axially. However, the torque generally does not need to overcome friction resulting from engagement of spring 1029 and collar 1040 and engagement of collar 1040 and cover 1006 (or, at least, this friction is significantly reduced and the corresponding adjustment torque is significantly reduced).
Nozzle 1000 also includes a frustoconical brake pad 1030. As can be seen in FIGS. 2 and 5-7, the brake pad 1030 is part of a brake disposed in the deflector 1008, which maintains the rotation of the deflector 1008 at a relatively constant speed irrespective of flow rate, fluid pressure, and temperature. The brake includes the brake pad 1030 sandwiched between a friction disk 1028 (above the brake pad 1000) and a seal retainer 1032 (below the brake pad 1032). The friction disk 1028 is held relatively stationary by the shaft 1020, while the seal retainer 1032 rotates with the deflector 1008. During operation of the nozzle 1000, the seal retainer 1032 is urged upwardly against the brake pad 1030, which results in a variable frictional resistance that maintains a relatively constant rotational speed of the deflector 1008 irrespective of the rate of fluid flow, fluid pressure, and/or operating temperature.
As can be seen in
In other brake designs, difficulties have been found in braking properly at low power input. The power input is determined generally by fluid pressure and/or flow rate and corresponds generally to the rotational force directed against the deflector by the impacting fluid. At low power input, where there is significant frictional engagement between the brake pad and other braking components, there has been too much braking, which may lead the nozzle to stall. For example, if the bottom surface of the brake pad 1030 has a horizontal portion as its bottommost surface, the brake pad 1030 will tend to cause too much friction at low power input. This issue is exacerbated at different operating temperatures because the lubricant viscosity changes at different temperatures, which results in too much friction at low power input at certain temperatures.
At low power input, the seal retainer 1032 is urged slightly upwardly against the bottom surface 1033 of the brake pad 1030. As can be seen in
At high power input, the seal retainer 1032 is urged upwardly against the bottom surface 1033 of the brake pad 1030 such that the brake pad 1030 is substantially flattened. In this circumstance, the thick outermost annular lip 1038 is sandwiched between the friction disk 1028 and seal retainer 1032, and most of the friction (and braking) results from the engagement of the thick outer lip 1038 with the seal retainer 1032. This engagement results in significant braking at high power input. Accordingly, with relatively little braking at low power input and relatively significant braking at high power input, the brake provides a relatively constant deflector rotation speed, irrespective of flow rate, fluid pressure, and operating temperature.
Further, with respect to nozzle 1000, a cap 1026 is provided (preferably composed of stainless steel or a similar material) to provide protection to the brake against mishandling, misuse, and environmental exposure. As can be seen in
The deflector 1008 includes a protruding flange 1009 at the top of the deflector 1008. The flange 1009 includes two cut-outs 1111 disposed preferably 180 degrees apart and corresponding to the slots 1021 and walls 1023 of the cap 1026. The cap 1026 is inserted in a circular groove 1012 formed in the top of the deflector 1008 and disposed within the groove 1012 so as to position the cap walls 1023 within the deflector cut-outs 1011. The walls 1023 are then punched inward to deform them and to thereby lock the cap 1026 to the deflector 1008. The energy needed to attach the cap 1026 is much less than the energy needed to detach the cap 1026 from the deflector 1008, and this manner of attachment is a way of tamper-proofing the nozzle 1000. Further, if a vandal removes the cap 1026 and causes internal damage, this action could be seen from the condition of the cap 1026 and deflector 1008, and it would be evident that such internal damage was not related to the fabrication process.
Also, as should be evident, the shaft and rib structure may be adapted to increase concentricity of the shaft 1020 and to increase the flow rate through the nozzle body 1016. It has been found that, during operation, the shaft 1020 is exposed to side loads and torsion effects from fluid flow. The central hubs of the valve sleeve 1004 and nozzle cover 1006 must provide adequate support so the shaft 1020 keeps its alignment and concentricity. When the shaft 1020 is misaligned, the flow rate may be reduced considerably.
As shown in
With respect to nozzle 1000, as shown in
Also, with respect to nozzle 1000, the deflector 1008 and valve sleeve 1004 preferably include a relatively few number of teeth, and in this preferred form, they each include six teeth. As can be seen in
As can be seen in
It will be understood that various changes in the details, materials, and arrangements of parts and components which have been herein described and illustrated in order to explain the nature of the sprinkler head may be made by those skilled in the art within the principle and scope of the sprinkler and the flow control device as expressed in the appended claims. Furthermore, while various features have been described with regard to a particular embodiment or a particular approach, it will be appreciated that features described for one embodiment also may be incorporated with the other described embodiments.
