U.S. patent application number 11/445705 was filed with the patent office on 2006-12-21 for water supply system for a linearly moving sprinkler irrigation system.
Invention is credited to Samuel J. Marcy.
Application Number | 20060283507 11/445705 |
Document ID | / |
Family ID | 37572167 |
Filed Date | 2006-12-21 |
United States Patent
Application |
20060283507 |
Kind Code |
A1 |
Marcy; Samuel J. |
December 21, 2006 |
Water supply system for a linearly moving sprinkler irrigation
system
Abstract
A water supply system is described for supplying water to a
linearly moving irrigation system. The water supply system is able
to take water from a stationary water supply conduit (either a
collapsible conduit or a rigid conduit) and feed it into one end of
a feed pipe for the irrigation system. The water supply system
includes a pickup shoe which extends into the water supply conduit
through a traveling opening in the top side of the conduit. The
pickup shoe intercepts substantially all of the water in the supply
conduit and pumps it upwardly through the traveling opening to the
feed pipe for the irrigation system. The pump is located in the
portion of the shoe which extends into the supply conduit. In
another embodiment, the water supply conduit can be an open
channel.
Inventors: |
Marcy; Samuel J.; (Cheyenne,
WY) |
Correspondence
Address: |
Dean P. Edmundson
P.O. Box 179
Burton
TX
77835
US
|
Family ID: |
37572167 |
Appl. No.: |
11/445705 |
Filed: |
June 2, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60688117 |
Jun 7, 2005 |
|
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Current U.S.
Class: |
137/580 |
Current CPC
Class: |
Y10T 137/86268 20150401;
Y02A 40/237 20180101; Y02A 40/22 20180101; A01G 25/097
20130101 |
Class at
Publication: |
137/580 |
International
Class: |
E03B 1/00 20060101
E03B001/00 |
Claims
1. A water supply system for a moving irrigation system comprising:
(a) a stationary closed conduit with a traveling opening therein;
wherein said conduit contains a supply of irrigation water; (b)
means for intercepting any water flowing in said stationary closed
conduit before said water reaches said traveling opening; wherein
said means for intercepting comprises a pickup shoe which closely
conforms to the interior shape of said closed conduit; (c) pump
means within said pickup shoe for pressurizing the intercepted
water and discharging the intercepted water upwardly through said
pickup shoe; wherein said pickup shoe extends upwardly through said
traveling opening in said stationary closed conduit; and wherein
said pickup shoe is operatively connected to said moving irrigation
system for supplying water from said stationary closed conduit to
said irrigation system.
2. The water supply system of claim 1, wherein said stationary
closed conduit comprises a collapsible thin-walled plastic tube
having a longitudinal slit, wherein said slit is sealed by a
reclosable fastener assembly that can be parted to form said
traveling opening.
3. The water supply system of claim 2, wherein said reclosable
fastener assembly comprises a pair of complementary-shaped fastener
sections which fasten to each other to form a seam.
4. The water supply system of claim 3, wherein said reclosable
fastener assembly comprises first and second sliders which
delineate said traveling opening; wherein said first slider is
adapted to separate or join said fastener sections upstream of said
pickup shoe, and said second slider is adapted to join or separate
said fastener sections together downstream of said pickup shoe.
5. The water supply system of claim 3, wherein said fastener
sections fasten to each other by a press fit.
6. The water supply system of claim 1, wherein said stationary
closed conduit comprises a rigid conduit having a longitudinal slit
that is normally closed by spring forces in the walls of said rigid
conduit.
7. A water supply system for a moving irrigation system comprising:
(a) a stationary open channel conduit carrying a supply of water;
(b) means for intercepting any water flowing in said stationary
open channel conduit; wherein said means for intercepting comprises
a pickup shoe; and (c) pump means within said pickup shoe for
pressurizing the intercepted water and discharging the intercepted
water upwardly through said pickup shoe; wherein said pickup shoe
extends upwardly and is operatively connected to said moving
irrigation system for supplying water from said stationary open
channel conduit to said irrigation system.
8. A water supply system in accordance with claim 7, wherein said
open channel conduit has a cross-section that conforms to a flared
inlet on said pickup shoe.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon, and claims priority from, my
Provisional Application No. 60/688,117, filed Jun. 7, 2005.
FIELD OF THE INVENTION
[0002] This invention relates generally to field irrigation
systems. More particularly, this invention relates to linearly
moving sprinkler systems. Even more particularly, this invention
relates to water supply systems for supplying water from a
stationary conduit at a continuously changing location to a
linearly moving sprinkler irrigation system.
BACKGROUND OF THE PRIOR ART
[0003] Efficient irrigation of large fields with sprinklers
requires that a relatively small number of sprinkling nozzles be
moved over the field. One method of accomplishing this is to mount
these nozzles on an overhead moving pipeline. The most prominent
system now in use is called a center pivot and consists of an
overhead pipeline supported by towers on wheels. The overhead
pipeline rotates about a fixed point called the pivot. Water is
supplied to the pipeline at this fixed pivot point and flows
radially outward to the nozzles mounted on the pipeline. The
resulting paths taken by the nozzles are concentric circles.
Disadvantages of the center pivot system are adapting the circular
pattern to square or rectangular fields and the fact that each
nozzle travels at a rate proportional to its distance from the
pivot point and must therefore be individually calibrated such that
the rate of water application is as uniform as possible over the
entire field.
[0004] Linear systems, sometimes called lateral move systems, also
consist of an overhead pipeline supported by towers on wheels.
Linear systems move perpendicular to the axis of the pipeline such
that all points on the pipeline move at the same rate. Linear
systems alleviate the two listed disadvantages of the center pivot
system because their spraying patterns are rectangular and each
nozzle sprays at the same rate, but they create another problem of
their own. This problem is getting the supply water into the moving
linear irrigation system. Because of this problem and the high cost
of overcoming it with existing technology, linear systems are not
now as widely used as are center pivot systems.
[0005] In general, there are two methods that are now in use to get
supply water into a moving linear irrigation system. They are the
ditch feed method and the hose drag method. The ditch feed method
requires that there be an open ditch adjacent to or through the
field carrying more water than is needed to irrigate the field. For
the great majority of fields, this is not feasible, so that the
hose drag method is now the most prevalent method of getting supply
water into a moving linear irrigation system. A hose drag system
consists of a hose attached at one end to a fixed hydrant and at
the other end to the moving overhead pipeline system. The hose is
doubled back on itself with a 180.degree. bend so that it can
accommodate the changing distance between the fixed hydrant and the
moving overhead pipeline.
[0006] Hose drag systems are cumbersome and expensive. The length
of hose that can be dragged is limited by the traction of the drive
wheels of the linear irrigation system and this limit is generally
less than desired. Thus, more than one hydrant is needed, which
requires additional underground pipelines to the additional
hydrants. Switching from one hydrant to the next is a significant
chore that requires a shut-down of the system while the hose is
dragged to the next hydrant. To accommodate the high flow rates
necessary to irrigate large fields, the hose must be relatively
large in diameter and therefore heavy when filled with water.
Forces required to drag it are substantial. The hose itself must be
strong enough to transmit these forces. The hose must also be
flexible and resistant to wear. A smooth strip of land at least
twice as wide as the minimum bending radius of the hose must be
provided for dragging the hose, and this strip of land cannot
otherwise be utilized. Clearly, there is a need for a better system
for getting supply water to a moving linear irrigation system.
[0007] In 1971 U.S. Pat. No. 3,592,220 (Reinke) was issued for a
LINEAR IRRIGATION SYSTEM WITH PICKUP SHOE. The patent discloses a
system for withdrawing fluid from a stationary closed conduit at a
continuously changing location in order to supply a linear
irrigation system. However, a system using the concept disclosed in
the patent is not available on the market.
[0008] In the aforementioned Reinke patent, it appears that the
water conduit 104 must be rigid, and the water in the conduit must
be pressurized in order to keep the slit closed in the top of the
conduit. It further appears that the water pressure in conduit 104
is substantially the same along the full length of that conduit,
both upstream and downstream from the pickup shoe 94. Another
disadvantage of the Reinke system is that a peripheral seal 102 is
required which is external to the conduit and extends the length of
the pickup shoe. The seal is subject to leakage whenever the pickup
shoe and the conduit are not in perfect alignment.
[0009] Another type of prior art includes the technology previously
used in designs for closing plastic bags and is marketed under
trade names such as ZIPLOC, HEFTY ONE, ZIP, GLAD LOCK, and others,
and it is disclosed in numerous patents including U.S. Pat. Nos.
4,212,337; 3,173,184; 5,664,299; and many others.
SUMMARY OF THE INVENTION
[0010] The present invention provides apparatus and techniques to
get supply water from a fixed location such as a well or hydrant to
a moving linear irrigation system in an economical and convenient
manner. Water from the fixed location is directed to a stationary
water conveyance system that can be either a closed conduit or an
open channel conduit. The stationary water conveyance system has a
traveling opening or a continuous opening such that a pressurizing
pickup shoe mounted on a moving linear irrigation system can extend
down through the traveling or continuous opening in the stationary
water conveyance system to take water from that system. The
pressurizing pickup shoe comprises (1) an inlet for intercepting
the water in the stationary water conveyance system (i.e. a
conduit), (2) a seal (preferably around the periphery of the
portion of the pickup shoe which is inside the conduit) for
maximizing the amount of water intercepted and for separating that
portion of the conduit containing water from the downstream portion
that should be empty; (3) a pump for pressurizing the water in the
pickup shoe; and (4) a suitable channel for passing the water up
through the traveling opening into the moving linear irrigation
system. The channel can be shaped to conform to the shape of the
traveling opening in the stationary water conveyance system (i.e.
conduit). The channel must contain a compartment for getting power
down to the pump and must furnish structural support for the pump,
the pump motor and the rest of the pressurizing pickup shoe.
[0011] The first embodiment of the present invention utilizes a
thin-walled flexible and collapsible plastic tube for the
stationary water conveyance system (i.e. the water conduit). The
thin-walled plastic tube has a longitudinal slit running the length
of the tube, and the slit is closed with a long adaptation of a
reclosable fastener assembly such as those used to open and close
small plastic household containers and know by tradenames such as
ZIPLOC, HEFTY ONE ZIP, GLAD.LOCK or other similar identities.
[0012] A second embodiment of the invention uses a rigid stationary
closed conduit with a slit running the length of the rigid
stationary closed conduit. The slit is held in a normally closed
position by spring forces that are either built into the wall of
the stationary closed conduit or press against the external wall of
the stationary closed conduit. The flattened and streamlined neck
of the pressurizing pickup shoe has a wedge shape on each end that
pries open the slit as the linear irrigation system moves along the
slitted rigid stationary closed conduit. Flanges extending radially
outward can be provided on both sides of the slit, both to
facilitate the prying and to assist in sealing the slitted rigid
stationary closed conduit against leakage.
[0013] A third embodiment of the invention uses a formed open
channel in place of the stationary closed conduit of embodiments
one and two. The cross-sectional shape of the formed open channel
conduit is compatible with the shape of the lower part of the
pressurizing pickup shoe.
[0014] In addition to supplying water to a linearly moving
sprinkler irrigation system, the invention may also be used to
supply water to high pressure squirt guns, thereby replacing the
costly heavy duty hose reels now in use.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 illustrates the most common prior art method now in
use for getting supply water to a linear irrigation system.
Typically the four-wheel cart shown in FIG. 1 will have a platform
on which an engine, generator or oil pump and various panels and
controls are mounted, but the platform and items mounted thereon
are not shown here for reasons of clarity.
[0016] FIG. 2 is similar to FIG. 1 except that the present
invention is used for getting supply water to the linear irrigation
system.
[0017] FIG. 3 is a cross-sectional view of a thin-walled flexible
conduit taken along line 3-3 of FIG. 2, where the conduit is filled
with water.
[0018] FIG. 4 is a cross-sectional view of a thin-walled flexible
conduit taken along line 4-4 of FIG. 2 after the water has been
removed by a pressurizing pickup shoe.
[0019] FIG. 5 is an enlarged view of the pressurizing pickup
shoe.
[0020] FIG. 6 is a perspective view of that portion of the
pressurizing pickup shoe that would remain after a longitudinal cut
along the center line of the pressurizing pickup shoe.
[0021] FIG. 7 is a plan view of that portion of the pressurizing
pickup shoe that would remain after a horizontal cut through the
flattened and streamlined neck of the pressurizing pickup shoe.
[0022] FIG. 8 is a perspective view of that portion of the
pressurizing pickup shoe that would remain after a lateral cut
along plane 8-8, as indicated by line 8-8 on FIG. 7.
[0023] FIG. 9 is a perspective view similar to FIG. 8 except that
FIG. 9 illustrates the connection apparatus necessary when a press
fit type of closure fastening device is utilized. The location of
the lateral cut of FIG. 9 is indicated by line 9-9 in FIG. 7.
[0024] FIG. 9A is an enlarged view of a portion of the
cross-sectional cut of FIG. 9 illustrating the guideways that hold
the closure fastening device while it is disengaged.
[0025] FIG. 9B is an enlarged view of a portion of FIG. 9 that
illustrates the roller mechanism that is used to open and close the
closure fastening device.
[0026] FIG. 10 illustrates a prior art type of closure fastening
device from U.S. Pat. No. 4,212,337 that can be utilized in the
present invention.
[0027] FIG. 11 illustrates another type of prior art closure
fastening device from U.S. Pat. No. 5,664,299 that can also be
utilized in the present invention.
[0028] FIG. 12 is similar to FIG. 11 except that a modification has
been made wherein the walls of the zipper profile extend in
opposite directions from the slider.
[0029] FIG. 13 is similar to FIG. 7 except that FIG. 13 illustrates
the pressurizing pickup shoe needed for the second embodiment of
the invention which utilizes a rigid stationary closed conduit in
place of the flexible and collapsible stationary closed conduits of
embodiment one. FIG. 13 is a plan view of that portion of a
specially adapted pressurizing pickup shoe that would remain after
a horizontal cut through the neck of the pressurizing pickup
shoe.
[0030] FIG. 14 is a cross-sectional view of a rigid stationary
closed conduit as utilized in the second embodiment of the
invention. The cross-section is taken along line 14-14 in FIG.
13.
[0031] FIG. 15 is a cross-sectional view of a rigid stationary
closed conduit taken at a location where the rigid stationary
closed conduit is pried open by the pressurizing pickup shoe as
indicated by line 15-15 on FIG. 13.
[0032] FIG. 16 illustrates a method for assembling the rigid
stationary closed conduit utilized in the second embodiment of the
invention to get the necessary pre-stressing forces for holding the
seam closed.
[0033] FIG. 17 illustrates the third embodiment of the invention
wherein a formed open channel is used for the stationary water
conveyance system.
DETAILED DESCRIPTION OF THE INVENTION
[0034] FIG. 1 shows a prior art technique and system for getting
water into a linear irrigation system and sprayed onto crops. Water
from hydrant 11 enters hose 12, which is connected to cart 13 at
either point 14a or 14b. The water then flows up vertical feed pipe
15 to a swivel connection 16, thence out into a main water line 17.
The water then flows down through drops 18 to nozzles 19 where it
is sprayed onto the crops. Swivel connection 16 enables the main
line to be rotated 180.degree. so that crops on the opposite side
of cart 13 can be irrigated. The main water line 17 is supported by
truss structure 20. Cart 13 has drive wheels 21 which propel the
cart 13 down the field, dragging one end of hose 12 along with
it.
[0035] FIG. 2 illustrates how the present invention connects with
the sprinkler apparatus of the type shown in FIG. 1. Water is
directed into stationary closed conduit 22. Conduit 22 has a
traveling opening 23 that moves together with cart 13 such that the
traveling opening 23 remains directly under cart 13. A pressurizing
pickup shoe 24 extends through traveling opening 23 into conduit
22. Pressurizing pickup shoe 24 picks up water from the conduit 22,
pressurizes it, and directs it out through traveling opening 23
into vertical pipe 15. The water then proceeds onto the crops in
the same manner as in the system described and illustrated in
connection with FIG. 1.
[0036] FIG. 3 illustrates an approximation of a typical
cross-section of stationary closed conduit 22 at points between the
water source and cart 13 where the conduit is full of water.
Conduit 22 can be a thin-walled flexible plastic tube. Conduit 22
has a longitudinal seam 25 that runs the length of the conduit 22.
Longitudinal seam 25 is an adaptation of any one of numerous
reclosable fastener assemblies of the prior art such as those used
to open and close small plastic household containers and are known
by trade names such as "Ziploc", Hefty One Zip, GLAD.LOCK, or
similar identities. Longitudinal seam 25 is normally closed but can
be opened to create traveling opening 23.
[0037] FIG. 4 illustrates a typical cross-section of stationary
closed conduit 22 at points downstream from cart 13 after
pressurizing pickup shoe 24 has taken the water out of conduit
22.
[0038] FIG. 5 is an enlarged view of pressurizing pickup shoe 24
with stationary closed conduit 22 in place. Sliders 26a and 26b
open and close seam 25. When pressurizing pickup shoe 24 and hence
the whole linear irrigation system is moving to the left on FIG. 5,
slider 26a will be opening seam 25, and slider 26b will be closing
seam 25. When pressurizing pickup shoe 24 is moving to the right on
FIG. 5, slider 26a will be closing seam 25, and slider 26b will be
opening seam 25. Sliders 26a and 26b are attached to pressurizing
pickup shoe 24 by brackets 27. Seam 25 is open between sliders 26a
and 26b, and is therefore separated into two parts, 25a and 25b.
Seam part 25a is visible and is designated on FIG. 5, while seam
part 25b is on the back side of pressurizing pickup shoe 24 and
invisible on FIG. 5. Flange 28 connects pressurizing pickup shoe 24
with vertical feed pipe 15.
[0039] FIG. 6 is a perspective view of that portion of pressurizing
pickup shoe 24 that would remain after a longitudinal cut along the
center line and shows the inside of said pressurizing pickup shoe
24. Because the walls of conduit 22 are too thin to be properly
illustrated at the cutting plane by a pair of lines with cross
hatching between them, the wall of conduit 22 is illustrated at the
cutting plane by a single line with cross hatching across said
single line.
[0040] Water enters pressurizing pickup shoe 24 through flared
inlet 29. The maximum circumference of flared inlet 29 is at
location 30 and is slightly smaller than the circumference of
stationary closed conduit 22 such that there will be a close fit of
conduit 22 over flared inlet 29. The shape of flared inlet 29 at
location 30 conforms approximately to the cross-sectional shape of
closed conduit 22 as shown in FIG. 3. As noted in the foregoing,
FIG. 3 is only an approximation to the shape that stationary closed
conduit 22 will assume when full of water. The exact shape depends
upon flow and pressure. A thin-walled plastic tube can only
withstand very minimal pressure, so that the pressure in stationary
closed conduit must be very low, almost nil. The lower the pressure
in conduit 22, the flatter the cross section depicted in FIG. 3
will be.
[0041] The circumference of flared inlet 29 at the leading edge 31
is smaller than at location 30, and said leading edge 31 is rounded
and turned inwardly in order to prevent snagging of conduit 22 as
pressurizing pickup shoe 24 moves along said conduit 22. The
trailing edge 32 of flared inlet 29 is circular and conforms to
pump housing 33. Fasteners 34 attach flared inlet 29 to pump
housing 33. If desired, a seal may be provided on the surface of
inlet 29 so that there is only minimal leakage of water around the
shoe. The seal may be comprised of soft pliable rubber or plastic
and may be fastened to the surface of inlet 29 by means of glue or
by mechanical fastener.
[0042] Pump 35 takes low pressure water from flared inlet 29 and
discharges it at a higher pressure into diffusion chamber 36. If
pump 35 operates too slowly, the system may become flooded. If pump
35 operates too fast, it may collapse flexible conduit 22.
Therefore, pump 35 needs to be a variable speed pump governed by
pressure sensors in the inlet region.
[0043] As shown in FIG. 6, pump 35 is located in the portion of the
shoe 24 which is located within the conduit 22. The pump 35
receives the low pressure water from conduit 22 and pushes
pressurized water upward out of the shoe and into the sprinkler
supply line. In contrast to the system described in U.S. Pat. No.
3,592,220 (Reinke), there is no pressure at the traveling opening
in the stationary water conveyance system of the present invention.
The rigid pressurizing pickup shoe 24 extends through the traveling
opening and upstream a short distance. After the water is
pressurized in the pressurizing pickup shoe, the water is
completely contained within a rigid system until the water exits
the sprinkler system. A seal around the leading edge of the pickup
shoe upstream from the traveling opening separates the portion of
the stationary water conveyance system that is carrying water from
the part that is empty. The seal is only subjected to the low
pressures of the stationary water in the conduit 22. Because of the
close fit between the pickup shoe and the interior surface of the
conduit 22, essentially all of the water in the conduit 22 must
pass into the leading end of the pickup shoe and pump 35.
Consequently, conduit 22 is substantially void of water at all
locations downstream from the pump, including the location of the
traveling opening.
[0044] Pump 35 takes low pressure water from flared inlet 29 and
discharges it at a higher pressure into diffusion chamber 36. Pump
35 is a variable speed pump governed by pressure sensors in the
inlet region. The pump may be, for example, a Goulds 6DHLC 2-stage
LS Bowl pump powered by a S12972 460 V 3 ph 10 HP submersible
motor. A pressure transducer located within the interior of inlet
29, and providing 1 ft. of amplitude control, sends signals to an
ABB variable frequency drive 15 HP controller. The controller is
located on cart 13 and will vary the frequency of the power to the
pump motor 41 such that the pump 35 operates at the right speed at
all times.
[0045] Diffusion chamber 36 has a relatively long thin slot on the
top side which spreads the compact concentrated stream coming out
of pump 35 into a confined stream wide in the direction
longitudinal to conduit 22 and narrow in the direction lateral to
conduit 22 so that this confined stream can pass through traveling
opening 23 in stationary closed conduit 22 with as little
disruption to the structural integrity and continuity of said
conduit 22 as possible. The component of pressurizing pickup shoe
24 that extends through traveling opening 23 in said conduit 22 is
called the neck and is given designation 37 in the drawings. Water
passes from neck 37 into concentrating chamber 38 through a long
thin slot in concentrating chamber 38. Concentrating chamber 38
consolidates the water flow into a compact stream and feeds said
water flow into vertical pipe 15 of the linear irrigation
system.
[0046] In addition to conveying water out of stationary closed
conduit 22, neck 37 must also convey energy down into conduit 22 in
order to operate pump 35. Therefore, a small portion of neck 37 is
divided off from the water carrying portion by wall 39. Wall 39
extends out and forms one end of both diffusing chamber 36 and
concentrating chamber 38. Either hydraulic or electrical energy is
supplied through duct 40 to motor 41, which converts it to
mechanical energy and transmits said mechanical energy to pump 35
via shaft 42. A combination bearing and seal 43 is mounted on wall
39 and supports shaft 42. Motor 41 is housed in motor housing 44.
Bearing 45 is mounted in the base of fairing 46 and supports shaft
42. The function of fairing 46 is to facilitate a smooth transition
of conduit 22 between being full of water and being empty, as
depicted in FIGS. 3 and 4. When the linear irrigation system and
hence the pressurizing pickup shoe are moving to the right in FIG.
6, fairing 46 will penetrate into the collapsed portion of conduit
22 and open up the cross section. Seam 25 will remain closed until
it reaches slider 26b. When the systems are moving to the left in
FIG. 6, fairing 46 will help the collapsing portion of conduit 22
to lay out smoothly. Fasteners 47 attach fairing 46 to motor
housing 44.
[0047] Heretofore, the various components of the pressurizing
pickup shoe 24 have been discussed with regard to function. Turning
to manufacturing and assembly, flared inlet 29 requires a smooth
and gradual transition in cross-sectional shape between the leading
edge, location 30, and the trailing edge 32 such that flared inlet
29 may be most conveniently constructed out of fiberglass over a
suitable mold. The most economical and practical shape for
diffusion chamber 36, concentrating chamber 38, pump housing 33,
and motor housing 44 are cylindrical. Pump housing 33 and diffusion
chamber 36 can be one monolithic piece. Short lengths of the same
tubing can be used for concentrating chamber 38 and motor housing
44. Wall 39 is cut out and welded to the appropriate ends of
diffusion chamber 36 and concentrating chamber 38. Motor housing 44
is aligned with diffusing chamber 36 and welded to wall 39 on the
assembly. Two plates are formed and welded to the assembly to make
neck 37. Pump 35 is inserted into pump housing 33 from the flared
inlet 29 end of said pump housing 33. Motor 41 is inserted into
motor housing 44 from the fairing 46 end of motor housing 44.
Although shown in FIG. 6, sliders 26a and 26b are assembled with
stationary closed conduit 22. Standard and known techniques can be
used for the remainder of the fabrication and assembly of
pressurizing pickup shoe 24.
[0048] FIG. 7 is a plan view of that portion of the pressurizing
pickup shoe 24 that would remain after a horizontal cut through
neck 37 at a location just below the point where neck 37 meets
concentrating chamber 38. When seam 25 is in the open position, the
two separated halves are designated 25a and 25b. Seam half 25b was
behind neck 37 and not visible in FIG. 5. Thus, 25b appears for the
first time in FIG. 7. For purposes of clarity, shaft 42 is not
shown in FIG. 7 even though it would be visible in the cavity of
neck 37. However, the combination bearing and seal 43 that supports
shaft 42 in wall 39 is shown in FIG. 7.
[0049] FIG. 8 is a perspective view of that portion of pressurizing
pickup shoe 24 that would remain after a lateral cut through the
forward portion of said pressurizing pickup shoe 24 at the location
indicated on FIG. 7 by line 8-8. Again, because the walls of
conduit 22 are too thin to be properly illustrated at the cutting
plane by a pair of lines with cross-hatching between them, the wall
of conduit 22 is illustrated at the cutting plane by a single line
with cross-hatching across said single line.
[0050] FIG. 9 is similar to FIG. 8 except that FIG. 9 illustrates a
press fit type of closure fastening device in place of the double
slider arrangement illustrated in FIG. 8. U.S. Pat. No. 4,212,337
discloses an example of a press fit type of closure fastening
device. A press fit type of closure may require that the two halves
of seam 25 be held in guides when they are separated and include an
apparatus for pressing the two halves together. FIG. 9 and FIG. 9A
illustrate the guideways. One guideway 48 would hold half seam 25a
and another guideway 49 would hold half seam 25b. FIG. 9B
illustrates a tapered finger 50 that would slide into the cavity of
seam 25 in order to open said seam 25 by separating half seam 25a
from half seam 25b. FIG. 9B also illustrates a pair of rollers 51
that press seam half 25b into seam half 25a, thereby causing them
to meld into seam 25. Rollers 51 are supported by brackets 52a and
52b. Brackets 52a are attached to pressurizing pickup shoe 24 on
the outside of stationary closed conduit 22, and brackets 52b are
attached to pressurizing pickup shoe 24 at a location that is
inside stationary closed conduit 22. Another tapered finger 50, a
pair of rollers 51 and their supporting brackets 52a and 52b are
also located on the opposite end of neck 37 of pressurizing pickup
shoe 24 and not shown in FIG. 9.
[0051] FIG. 10 is similar to FIG. 7 of U.S. Pat. No. 4,212,337 with
the numerical designations of that patent removed and with finger
50 added to the illustration. Finger 50 is tapered so that as said
finger 50 moves in one direction with respect to the closure
fastening device, dimension 53 will become larger and the closure
fastening device will be pried open. When finger 50 moves in the
opposite direction, dimension 53 will become smaller and finger 50
will disengage from the closure fastening device.
[0052] FIGS. 11 and 12 illustrate how a slight modification to
prior art can make closure fastening devices that were developed
primarily to seal household containers better suited for use in the
present invention. Household containers require complete closure at
both ends of the zipper profile. This can be best attained if the
walls to be sealed together both enter the slider on the bottom of
the slider and the two sides of the slider are interconnected
across the top of the slider. This arrangement will work in the
present invention but the seam that is formed will protrude outward
from a line defining the circumference of the stationary closed
conduit and may be subject to damage from ordinary wear and
tear.
[0053] FIG. 11 is similar to FIG. 3 of U.S. Pat. No. 5,664,299 with
the numerical designations of that patent removed and new numerical
designations added. FIG. 11 is a cross-sectional view of a slider
from the '299 patent near the front of the slider where the zipper
profile is open. The two container walls that are about to be
joined and sealed together enter the slider from the bottom. The
stradling slider has an inverted U-shaped member having an integral
top 54 and side walls 55 and 56. For use in the present invention,
the two container walls become walls 22a and 22b of stationary
closed conduit 22, and slider 26 is attached to bracket 27 by any
suitable connection between bracket 27 and the inverted U structure
of slider 26 consisting of top 54 and side walls 55 and 56.
[0054] FIG. 12 illustrates a similar slider that has had part of
top 54 removed and has been turned on its side so that walls 22a
and 22b can enter the slider from opposite sides. Because top 54
provided structural integrity between walls 55 and 56, an
alternative means of holding walls 55 and 56 in position must be
provided. One of the walls 55 and 56 is now on the inside of
stationary closed conduit 22, and the other is on the outside such
that the alternative structural connection between walls 55 and 56
must pass through traveling opening 23. Pressurizing pickup shoe 24
passes through traveling opening 23. Thus, the modification to the
slider that is illustrated in FIG. 12 requires a pair of brackets
27a and 27b for each slider, one of which is mounted on that
portion of pressurizing pickup shoe 24 that is on the outside of
stationary closed conduit 22, and the other of which is mounted on
that portion of said pressurizing pickup shoe 24 which is on the
inside of said stationary closed conduit 22.
[0055] FIGS. 13, 14, 15 and 16 illustrate a second embodiment of
the invention wherein a rigid stationary closed conduit 57 is
substituted for collapsible stationary closed conduit 22. Rigid
stationary closed conduit 57 has a longitudinal slit 58 that serves
the same purpose as seam 25 in collapsible stationary closed
conduit 22. Slit 58 is normally held closed and sealed by
spring-like forces that can be created by pre-stressing forces in
the walls of said rigid stationary closed conduit 57, or by other
means. When a linear irrigation system moves along rigid stationary
closed conduit 57, one half of a double wedge-shaped neck on a
specially adapted pressurizing pickup shoe pries slit 58 open to
create traveling opening 23.
[0056] FIG. 13 is similar to FIG. 7 and is a plan view of that
portion of a specially adapted pressurizing pickup shoe 24a that
would remain after a horizontal cut through neck 37a of said
pressurizing pickup shoe 24a at a location just below the point
where neck 37a meets concentrating chamber 38. Dimension 59 is the
maximum width of neck 37a. The value of dimension 59 is governed by
the amount of deflection that can be imposed on rigid stationary
closed conduit 57 without damage to said conduit 57. The length of
neck 37a is as necessary to pass the required amount of water from
rigid stationary closed conduit 57 to the linear irrigation system.
Pressurizing pickup shoe 24a is similar to pressurizing pickup shoe
24 except that neck 37a is shaped to conform with the traveling
opening in rigid stationary closed conduit 57, the flared inlet 29
is shaped to conform to the inside of rigid stationary closed
conduit 57, and fairing 46 is not required. Again, for purposes of
clarity, shaft 42 is not shown on FIG. 13 even though it would be
visible in the cavity of neck 37a.
[0057] FIGS. 14 and 15 are cross-sectional views of rigid
stationary closed conduit 57 taken along lines 14-14 and 15-15,
respectively, of FIG. 13. FIG. 14 illustrates a cross section at a
location away from pressurizing pickup shoe 24a where spring forces
hold slit 58 closed. FIG. 15 is a cross section near the center of
pressurizing pickup shoe 24a where rigid stationary closed conduit
57 has been pried open by said pressurizing pickup shoe 24a.
[0058] FIG. 16 illustrates one method for pre-stressing the walls
of rigid stationary closed conduit 57 in order to establish the
spring-like forces that will hold slit 58 in a normally closed and
sealed configuration. A circular pipe with a cross section as
designated by numeral 60 in FIG. 16 is manufactured by known
methods. The diameter of pipe 60 is smaller than the desired final
diameter of rigid stationary closed conduit 57 and has
circumferential reinforcing near the inside edge of the wall. Next,
a longitudinal slit is cut and twisting couples 61 are applied to
both sides of the slit such that the cross section opens up to
position 62. Then, flanges 63 with legs 64 are attached to the
edges of the slit in pipe 60, said legs 64 becoming part of the
circumference of rigid stationary closed conduit 57. When twisting
couples 61 are released, the material that originally comprised
pipe 60 will attempt to return to its original configuration but
will be unable to do so because legs 64 and part of flanges 63 are
in the way. Pipe 60 will then assume a new position with a larger
diameter and a pre-stress that will hold slit 58 normally closed
and become a part of rigid stationary closed conduit 57.
[0059] Reinforcing in the walls of pipe 60 can be designed to give
the desired stiffness in both the longitudinal and circumferential
directions by complicated but known methods of structural analysis
such as curved beam analysis and orthogonally anisotropic analyses.
Other techniques for obtaining pre-stressing forces are known.
[0060] A third embodiment of the invention utilizes a stationary
open channel in place of the stationary closed conduits of earlier
embodiments. An open channel may be feasible when the slope of the
field to be irrigated is uniform and mild. The third embodiment
differs from prior art in that a formed channel that conforms
precisely to a flared inlet on a pressurizing pickup shoe is
utilized such that virtually all of the water flowing in the open
channel is picked up and sprayed onto the field. Any flow that does
not get through the small gap between the flared inlet and the
formed open channel is leakage and must be minimized by suitable
sealing devices. The shape of the formed open channel can be as
desired. One possibility is a cross section similar to that of
rigid stationary closed conduit 57 as it appears in FIG. 15, except
that the width of the open slit could be larger so that the length
of the neck on the pressurizing pickup shoe could be shorter. The
slot would be open at all locations so that pre-stressing forces
would not be necessary.
[0061] FIG. 17 is a cross-sectional view of the third embodiment of
the invention showing the pressurizing pickup shoe in an open
channel. Flared inlet 29 and pump 35 with shaft 42 are similar to
those of embodiments one and two, as are neck 37 and flow
concentrating chamber 38. The inside surface of formed open channel
66 conforms to the external periphery of flared inlet 29. In order
to accommodate the relative motion between the stationary formed
open channel 66 and the moving flared inlet 29 there must be a
small gap between them. This gap is bridged by seal 65 which
minimizes flow that would bypass the pressurizing pickup shoe and
thus be wasted. Designation 67 indicates the approximate location
of the water surface in formed open channel 66. Diaphragm 68 is
attached to the pressurizing pickup shoe to prevent water from
overtopping flared inlet 29. Diaphragm 68 can be an integral part
of flared inlet 29. Finally, expansion joint 69 is installed in
line 15 to allow for some differential motion between the
pressurizing pickup shoe and cart 13.
[0062] Other variants are possible without departing from the scope
of this invention.
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