Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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The present invention relates to irrigation sprinkler
heads of the ro-tary type, and, more particularly, to
sprinkler heads dispersing water at a constant precipita-
tion rate according to a preselected pattern.
~ urbine driven pop-up sprinkler heads o~ the type
shown in my U.S. Patent No. 2,909,325 provided a step
increase in the art of irrigationO Previously, rotary
sprinklers were o~ the impact driven type wherein a high
velocity stream of water deflected a spring-loaded hammer
which nudged the sprinkler in a rotary direction about a
vertical pin-axis upon its return. Whereas such impact
driven sprinklers emitted a high precipitation rate water
1~ stream in order to effect the necessary Eorces to cause
rotation, the pop-up type sprinklers of my aEorementioned
patent employed a small water turbine wheel rotating at
relatively high speed to eEfect slow rotation of a
sprinkler nozzle turret on top. Accordingly, the emitted
stream or streams of water Erom one or more nozzle openings
in the rotating turret could be such as to efEect a low
precipitation rate of water dispersal to maximlze water
penetration t:o the desired area while minimizing undesired
water runoff
In my later issued U.S. Patent No. 3,85~,664, I
disclosed improvements to such turbine driven sprinlclers.
In particular, a bulkhead was disposed between the common
source of water under pressure and the plurality of nozzle
openings contained in a rotating turret. Each oE the
nozzles terminated iQ an opening wiping over the surface of
the bulkhead as the turret turned. By providing openings
in the bulkhead, the pathways to the nozzles were selec-
tively opened and shut as a function of the direction in
which the particular is instantaneously facing. In this
manner, a preestablished on/oEf spray pattern was put into
the sprinkler head~ However, the preestablished pattern
was limited to circular arcs.
In pattern sprinklers, a rectangular shape is very often
desirable, as most garden and landscape areas are on rectangular
lots surrounding rectangular buildings. Known sprinkler heads
creating a rectangular spray pat-tern are of the fixed and
oscillating type. The fixed type, having a plurality of holes ~n
the top, generally does not distribute water evenly over the entire
area and tends to be of a high precipi-tation rate type. The
oscillating type is large and is generally not suited to the
permanent irrigation systems, but rather to connection to the end
of a garden type hose for selective placement within an area to be
watered on a time-by-time basis.
Furthermore, in those prior art sprinklers capable of
watering a pre-established pattern, the size of the pattern is
changed by increasing or decreasing the pressure of the water
supplied to the sprinkler. By doubling the pressure, the area
coverable by the prior art sprinklers increases by approximately
four times. However, the gallonage discharged by the sprinkler
nozzles only increases by a factor of 1.41 (the square root of 2).
Accordingly, the precipitation rate is greatly reduced when the
prior art sprinklers are used to cover a larger area by increasing
the pressure of the water supplled to the sprinklers.
Accordingly, it is the principal aim of the present
invention to discharge water from a sprinkler head over a pre-
selected pattern at a constant precipitation rate.
The present invention seeks to provide in an irrigation
sprinkler head adapted for connecting to a source of pressurized
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water and havlng at least one nozzle which is revolved about a
vertical axis by the flow of water between the connection to the
water source and the nozzle to create a horizontal watering pat-
tern from the water emitted from the nozzle, nozzle opening
means for delivering a stream of water of variable volume and
distance from said nozzle and means for continuously and pro-
portionately exposing said opening means to said source of said
pressurized water according to a present function of said nozzle's
instantaneous rotation position as said sprinkler turns, whereby
said sprinkler head will create a horizontal spray pattern of
preset configuration and will supply a relatively constant volume
of water to all portions of said pattern, the improvement wherein
said nozzle opening means comprising: an opening for said nozzle
shaped as a radial "V" cut from a plane parallel to said vertical
axis of rotation to a plane normal to said axis and relative to
a point exterior of said nozzle, with said V-shape oE said opening
emitting a stream of water whose distance increases linearly with
the exposed length of said opening means to said source of
pressurized water and whose volume increases as the square of
exposed length to supply a volume of water through said opening
which increases as the square of distance of sa:id opening from
said axis and with the radial shape of said opening directing said
stream in a generally horizontal direction.
A constant precipikation rate is thereby maintained as
the volume of water dispersed from the nozzle increases as the
square of the distance of water must travel. The radial shape of
the opening directs the stream of water passing therethrough in a
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generally horizontal direction. The nozzle openinys are exposed
to the source of pressurized water by a bulkhead positioned be-
tween the openings and the water. The bulkhead has an opening
defining the spray pattern to be produced.
The present invention is Eurther illustrated in the
accompanying drawings, in which:
Figure 1 shows an elevational view of a pop-up sprinkler
according to the present invention;
Figure 2 shows a cross-sectional view of the nozzle
portion of the sprinkler shown in Figure l;
Figure 3 shows a sectional view of the nozzle of Figure 2,
taken through the plane III-III;
Figure 4 shows a sectional view of the nozzle of Figure
2, taken through the plane IV-IV; and
Figure S shows a detailed cross-sectional view of the
exposure of the nozzle opening to the water within the sprinkler
of Figure 1 via the pattern bulkhead disposed
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therein.
Referring more particularly to the drawings, Figure 1
shows an elevational view of a pop-up type sprinkler
assembly, generally denoted 20. The specific improvement
to a sprinkler of the present invention in its operating
portion is primarily embodied in the pop-up type sprinkler
assembly 20. A detailed description of such general
assemblies can be seen in my aforementioned prior patent
3,854,~64. For purposes of the present invention, assembly
20 will be described only briefly. Inlet pipe 22 from a
source of pressurized water leads into A closed sprinkler
body 24. The body 24 has a cap 42 with a circular opening
23 in the top thereof through which a cylindrical member 28
is disposed capable of sliding vertically up and down
l; through the circular opening 23. Cylindrical member 28 is
biased in a downward direction by biasing spring 20 and by
gravity. When pressurized water is introduced to the
sprinkler body 24, cylindrical member 28 is forced upwardly
through the circular opening 23 against the force of
gravity and the biasing spring 26. When water pressure is
turned off, cylindrical member 28 retracts once again into
the body 24 through the circular opening 23. A cylindrical
screen member 27 is disposed around cylindrical member 28
and has small openings to allow water to pass through but
ko prevent the passage into the operating sprinkler
mechanism oE particles sufficiently large as to Eoul the
operating n~echanism.
Disposed within cyclindrical member 28 and moving in
combination therewith is a turbine-gear motor drive,
generally denoted 34. The bottom of cylindrical member 28
contains a stator 32 having a hole 30 through which water
can pass and impinge upon an impeller 33 of the turbine-
gear motor drive 34. ~s the impeller 33 is rotated by the
water passing thoru~h the hole 30, a plurality of gears
3~ (not shown) attached thereto cause upper shaft 36 to be
rotated slowly. Upper shaft 36 is attached to a generally
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cylindrical nozzle assembly 44 according to the present
invention, causing it to rotate. The nozzle assembly 44
rotates wi~hin a ring member 48 disposed benea~h the upper
portion of the sprinkler body 24. The ring member 48 also
engages the closing spring 26 and the screen 27 to maintain
them in proper position within the sprinkler 20. ~ater
passing around the turbine-gear motor drive 34 enters the
nozzle assembly 44 and exits through the nozzle openings 52
to create emitted sprinkling water streams 56 as the nozzle
assembly 44 rotates. The specific improve~ents of the
present invention as incorporated within the known basic
pop-up sprinkler mechanism will now be described.
From basic hydrodynamics, it is known that fluid
pressure and distance are directly proportional, whereas
lS flow rate (and corresponding volume) are in a square
relationship to pressure. Thus, as the pressure of a
stream of water is doubled, the volume oE water in the
stream only increases by the square root oE two (1.41).
The only means of adjusting the sprinklers of the prior art
to cover a larger area is to increase the pressure to the
sprinkler head. Accordingly, if the pressure to a prior
art sprinkler is doubled, the sprinkler head would throw
water twice the distance. The amount of water from the
sprinkler head, however, would only increase by 1.41. The
2S result is that larger patterns can only be watered at a
lower preciptiation rate than smaller patterns with the
prior art sprinklers.
As mentioned, the other problem with the prior art
sprinklers is that the only type oE spray patterns
coverable are rectangular spray patterns. The prior art
sprinklers are not capable oE covering a nonrectangular
spray pattern o~ arbitrary shape.
The present invention overcomes all of these
limitations. Specifically, the nozzle assembly 44 is
provided with a plurality of nozzle openings 52, as shown
in more detail in Figures 2-S. As shown in Figure 2, each
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of the openings 52 is shaped in cross section to have a
radial shape relative to a point exterior of the nozzle
assembly 44. As shown in Figures 4 and 5, each of the
nozzle openings 52 appears as a "V" shape relative to a
plane normal to the axis of rotationO The noxzle assembly
of the present invention produces a tight, well-knit
plurality of streams due to the true arc curve oE the
nozzle opening 52.
As shown in Figure ~, the nozzle assembly 44 is a
generally cyldindrical element having a plurality of the
nozzle openin~s 52. Attached to the nozzle assembly 44,
via a screw 54 engaging a threaded opening 63 in the nozzle
assembly 44, is a top cap 46. The top cap 46 limits the
downward travel of the nozzle assembly 44 within the
sprinkler body ~4 under the force of gravity and ~he
closing spring 26. The cap 46 also has an integral helical
toothed ring 60, as will be described hereinafter.
The nozzle assembly 44 can be a molded plastic part.
The one-piece molding of the present invention is to be
contrasted with the nozzles of the prior art sprinklers
which were two-part assemblies welded together.
Disposed beneath the nozzle assembly 44 is a bulkhead
40 having a spray pattern opening 39 therein, as shown in
Figure 5. The bulkhead 40 is Eixedly mounted for non-
2~ rotation in the sprinkler body 20 by means o-E a slot ~4 on
the bulkhead 40 which engages a boss 62 extending outwardly
Erom the inner housing 28. The bulkhead 40 rests upon a
resilient sealing ring 38, which insures that all water
passing Erom within the sprinkler body 20 to the environ-
ment through the nozzle assembly 44 passes through thepattern opening 3g in the bulkhead 40.
The bulkhead 40 is preferrably of smooth, corrosion-
resistant, wear-resistant metal such as stainless steel.
High strength, wear-resis-tant, graphite filled plastic has
also been tried with some success. In operation, the spray
pattern 39 in the bulkhead 40 direc~s the water from within
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the sprinkler body 20 through the nozzle openings 52 as -the
length o the nozzle openings 52 is instantaneously and
continuously varied by the bulkhead 40.
With reference to Figure 5, one can easily envision
how the exposed length of the nozzle openings 52 are
changed as the nozzle assembly 44 rotates relative to the
bulkhead 40. ReEerring to Figure 5, it is seen that the
exposed length of the nozzle opening 5~ in the 9:00 o'clock
position is significantly less than the e~posed length of
the nozzle opening 52 in the 10:00 o'clock position. That
is, the efective opening of each of the nozzles 52 is
continuously varied as the nozzle assembly 44 rota-tes
relative to the bulkhead 44. As a result, each oE the
nozzle openings 52 will vary the projected distance oE
their associated water streams pro~ortionately to the
length oE the exposed nozzle openings. Most importantly,
the V shape of each of the nozæle openings (in a plane
normal to the shaft 36) provides a volume of water which
increases as the square oE the ]ength oE an exposure of the
nozzle opening 52 via the bulkhead 44. That is, with
reference to Figure 5, as the exposed length of the nozzle
opening 52 in the 10:00 o'clock position is approximately
twice the length of the exposed nozzle opening ~2 in the
9:00 o'clock position, the nozzle opening 52 in the 10:00
o'clock position will project a stream twice as Ear as the
nozzle opening 52 in the ~:00 olclock position and ~ith
four times the volume.
Accordingly, each nozzle emits a stream whose
distance increases linearly with the length oE the exposed
3~ nozzle opening 52 and whose volume increases as the square
of the exposed length of the nozzle opening 52. ThereEore,
the limitation oE the prior art sprinklers in covering
greater distances only by increasing the pressure, which
effected a corresponding decrease in the volume metric flow
rate has been overcome. The design oE the nozzle assembly
44 and the bulkhead 40 provides variable length streams o
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water at a constant volumetric ~low rate, thereby achieving
a relatively uniform precipitation rate over the entire
pattern to be watered. As should be obvious ~rom the
foregoing, the spray pattern acheivable with the present
invention can have any conEiguration employing straight or
curved boundaries, or any combination thereof. A rectangu-
lar spray pattern has ~een shown with the present invention
only to make easier the explanation oE its operation.
The ~oregoing demonstrates the simplicity of the
present invention and its eEfectiveness in not only in
generatiny streams having a distance of throw directly
proportional to the exposure of the nozæle opening to the
water within the sprinkler body 24, but also in delivering
the correct volume of water to each sector of the spray
pattern.
It should be noted that an increase or decrease in
the precipitation rate produced by the nozzle assembly 44
can be effected by changing the number of nozzle openings
52 in the cylindrical assembly 44. Prototypes of the
~0 invention have been made using 6, 9, 12 or 18 nozzle
openings 52 to change the precipitation rate over the
pattern to be covered. It has been found that 6 openings
with ~ pounds of pressure will produce a uniform precipi-
tation rate over a pattern which is 5 feet by 10 feet,
while 18 openings with 30 pounds of pressure produces an
even precipitation rate over a pattern of 25 ~eet b~ 55
feet. The precipitation rate is said to be constant
insoEar as a 1.5 to 1 ratio oE precipiatation between the
farther and closer areas oE the pattern is maintained.
Accordingly, the number of nozzles and the pressure of the
water supply is selected according to the particular size
of the pattern to be covered.
While the number of nozzle openings 52 may be changed
to vary the precipitation rate produced by the nozzle
assembly 52, it has been found that an optimum shape Eor
each nozzle opening is as Eollows, with reEerence to Figure
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g
5. Dimension ~ is optimally on the order oE .015 inches,
and dimension B is optimally 8 degreesO ~he radius o~
curvature of the curved portion oE the nozzle, (dimension
C) in Figure 2 is approximately .6 inches.
~s noted above, difEerent pressures and different
nozzle openings are used depending upon the si~e o~ the
pattern to be covered. For correct operation oE the
present invention, water at a relatively constant pressure
must be supplied to the sprinkler body. In this regard,
the inlet pipe 25 is preferrably connected to a pressure
regulator to insure a uniform pressure. An internal
pressure regulator may also be used with the invention.
The operation o~ the present invention is enhanced by
the inclusion oE a generally helical toothed ring Z0
attached to the top cap 46 on the nozzle assembly 4~. This
toothed ring, as shown in Figures 1, 2, and 4, is usecl to
deflect water Erom the nozzle openings 52 to an area closer
to the sprinkler 20. The top cap 4~ is rotatable relative
to the nozzle assembly 44 by way oE the screw 54 in the
boss 63 Eormed within the nozzle assembly 44. By rotating
the top cap ~6 downwardly, more of the teeth on the ring 60
are brought into contact with the emitted streams 5O to
deflect them closer ~o the sprinkler 20.
The toothed ring finds application with large spray
patterns and with corresponding high pressures in the
sprinkler body to propel the streams to cover the patterns~
If the pressure is reduced to achieve a smaller pattern or
area oE coverage, most of the water tends to fall in the
outer perimeter of the pattern. Accordingly, by adjusting
3~ the helical toothed ring 60 downwardly, the teeth on the
helical ring ~0 progressively encounters more of the
emitted streams and deflects these streams to reduce the
distance of throw. Thus, an increasing number of the
streams can be pulled in to correct the distribution
pattern that exists at low pressures. The toothed
adjustment ring 60 is adjusted downward if there is not
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enough water close to the sprinkler 20 and is adjusted
upward if there is too much water close to the sprinkler
20. ~s shown in cross section in Figure 2, the helical
nature of the ring is ac`nieved by having smaller teeth 60a
and larger teeth 60b on the ring.
The combination of the novel design oE the nozzle
assembly 44 and the bulkhead 40 when combined with the
helical toothed ring 60 acheives relatively uniform
watering over a wide variety of spray patterns.
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