U.S. patent number 3,896,999 [Application Number 05/508,631] was granted by the patent office on 1975-07-29 for anti-clogging drip irrigation valve.
Invention is credited to Jaime Sahagun Barragan.
United States Patent |
3,896,999 |
Barragan |
July 29, 1975 |
Anti-clogging drip irrigation valve
Abstract
An anti-clogging drip irrigation valve or dropper which can be
unclogged without the need of disassemblage, comprises a flat
relatively thick elongated assembly having a flexible film cover
member, a relatively thick highly flexible member laminated to said
cover member, at least one elongated channel means opening towards
one of the faces of said highly flexible member opposite to the
face laminated to said cover member, a plurality of partition means
integrally formed with said highly flexible member and located
within said elongated channel means in order to form labyrinth
conduit means with a first cavity means formed at one of the ends
of said elongated channel means and a second cavity means formed at
the opposite end of said elongated channel means; and complementary
cover means attached to said opposite face of said highly flexible
member and to said partition means at their free ends, so as to
complete a labyrinth passage means with said labyrinth conduit
means and a first and a second respective chamber means with said
first and second cavity means; fluid entrance means at one of said
chamber means; and fluid outlet means at the other of said chamber
means. The highly flexible nature of said relatively thick
elongated assembly provides for the capability of said assembly to
be squeezed and deformed to release all the obstructions or clogs
which might have been deposited by the flowing fluid, in order to
prevent clogging of said labyrinth passage means. The flat
relatively thick elongated assembly can be directly attached to a
complementary cover means consisting of a drip irrigation pipe
having a hole in a position matching one of said chamber means to
act as the fluid entrance means, or can be permanently adhered to a
complementary cover means comprising a film member to form a
disposable valve unit having connecting fluid entrance means at one
of said chamber means to be inserted into a drip irrigation
pipe.
Inventors: |
Barragan; Jaime Sahagun
(Michoacan, MX) |
Family
ID: |
19745450 |
Appl.
No.: |
05/508,631 |
Filed: |
September 23, 1974 |
Foreign Application Priority Data
Current U.S.
Class: |
239/107; 138/42;
239/500; 239/533.13; 239/542; 239/602 |
Current CPC
Class: |
A01G
25/02 (20130101); Y02A 40/22 (20180101) |
Current International
Class: |
A01G
25/02 (20060101); B05b 001/32 (); B05b
015/02 () |
Field of
Search: |
;239/107,451,455,500,502,512,516,517,519,521,534,542,570,571,574,602
;138/42,43 ;137/525,525.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Ward, Jr.; Robert S.
Attorney, Agent or Firm: Imirie, Smiley & Linn
Claims
What is claimed is:
1. An anti-clogging drip irrigation valve which comprises a flat
relatively thick elongated assembly having a flexible film cover
member, a relatively thick highly flexible member laminated to said
cover member, at least one elongated channel means opening towards
one of the faces of said highly flexible member opposite to the
face laminated to said cover member, a plurality of partition means
integrally formed with said highly flexible member and located
within said elongated channel means in order to form labyrinth
conduit means with a first cavity means formed at one of the ends
of said elongated channel means and a second cavity means formed at
the opposite end of said elongated channel means; complementary
cover means attached to said opposite face of said highly flexible
member and to said partition means at their free ends, so as to
form a labyrinth passage means from said labyrinth conduit means
and a first and a second respective chamber means from said first
and second cavity means; fluid entrance means at one of said
chamber means; and fluid outlet means at the other of said chamber
means.
2. An anti-clogging drip irrigation valve according to claim 1
wherein said flat relatively thick elongated assembly is a highly
flexible continuous ribbon-like member containing a plurality of
said elongated channel means and partition means separated by block
mans integrally formed in said relatively thick highly flexible
member.
3. An anti-clogging drip irrigation valve according to claim 1
wherein said flexible film cover member is a thin thermoplastic
film laminated to said relatively thick highly flexible member.
4. An anti-clogging drip irrigation valve according to claim 1
wherein said relatively thick highly flexible member comprises a
plastic foam material having closed or separate cells.
5. An anti-clogging drip irrigation valve according to claim 1
wherein said complementary cover means is a pipe of a drip
irrigation system, said fluid entrance means comprising openings in
said pipe matching each one of said one chamber means which
therefore will constitute fluid reception chamber means for the
drip irrigation valve.
6. An anti-clogging drip irrigation valve according to claim 5
wherein said fluid outlet means comprises a check valve formed by a
loose section provided at said other of said chamber means so as to
form an opening between said highly flexible member and said pipe,
whereby said other chamber means will constitute fluid emission
chamber means for the drip irrigation valve.
7. An anti-clogging drip irrigation valve according to claim 5
wherein said fluid outlet means comprises an opening provided
through said highly flexible member and communicating said other of
said chamber means to the environment.
8. An anit-clogging drip irrigation valve according to claim 1
wherein said complementary cover means is a flexible film having a
form complementary to the face of said relatively thick highly
flexible member, connector means being provided at one of the ends
of said highly flexible member to removably engage the thus formed
valve unit to a hole of a drip irrigation pipe.
9. An anti-clogging drip irrigation valve according to claim 8
wherein said connector means comprises an element selected from the
group consisting of a flanged nipple and a flexible tube.
10. An anti-clogging drip irrigation valve according to claim 8
wherein said fluid outlet means comprises a check valve formed by a
loose section provided at the other end of said highly flexible
member so as to form an opening between said highly flexible member
and said complementary flexible film, which opening will remain
opened as long as there is pressure in said elongated channel means
but will be closed if a relative vacuum is applied to said
elongated channel means.
Description
BACKGROUND OF THE INVENTION
The present invention refers to an anti-clogging drip irrigation
valve or dropper which can be attached to a drip irrigation pipe or
which can serve as a separate disposable element to be connected
thereto and, more particularly, it is related to an anti-clogging
drip irrigation valve which is formed by a labyrinth passage
provided in a highly flexible assembly in order to provide for its
deformation by squeezing so as to release any obstruction or clog
which might have been introduced in the passage.
As is well known, the drip irrigation method comprises applying
irrigation fluid in a perfectly controlled manner to the
neighborhood of the plants in order to keep a proportion of
moisture necessary to provide for its growth with a minimum
consumption of liquid. The drip irrigation systems require pipes
which are installed along the rows of plants and include bores to
which special droppers or valves are adapted, said valves being
coupled to the pipes at points suitable to control the outlet of
liquid. The valves which have been used in accordance with the
prior art for the purpose of controlling the outlet of the liquid
from the drip irrigation piping, can be generally embodied into two
different types, namely, droppers acting by obstruction and
droppers acting by friction.
The first type of droppers or valves includes a large multiplicity
of different types of drip irrigation devices having a member
capable of gradually closing and opening the bore of the valve in
order to provide for the dropwise emission of the liquid, such as
is necessary for this type of systems. The droppers or valves
working by friction, on the other hand, are provided with a very
long and narrow passage in order to force the irrigation liquid to
flow throughout the length of said passage, whereby a pressure drop
by friction is produced sufficient to obtain the dropwise emission
of the liquid at the outlet end of the passage.
A variant developed in the last years in connection with this type
of drip irrigation devices comprises a valve having a relatively
long and narrow passage to cause high friction losses, by the
incorporation of baffles or the like causing sharp changes of
direction in the path of the fluid flow, so as to cause impacts and
turbulences to produce a higher friction loss in each change of
direction, thereby enabling decrease in the lengths and increase in
the cross sections of the prior art passages.
The valve systems operating by obstruction, however, have left much
to desire, inasmuch as, regardless of the fact that they are
capable of preventing clogging in view of their characteristics of
comprising a movable member which can be removed to clean the
valve, they are nevertheless very difficultly controllable and very
easily disadjustable. Also, when there is a large amount of said
valves in an irrigated land, the control of each of the valves is
very troublesome, whereby these systems have been falling in
disuse, by virtue of the very high labor costs for maintenance and
control thereof. In effect, very frequently some of the droppers or
valves emit excessive amounts of irrigation liquid while others are
clogged and do not permit flow of liquid, whereby there is a high
disuniformity in the irrigation rate, which is detrimental to the
growth of the plants being served thereby.
On the other hand, the drip irrigation systems having valves
systems working by friction loss have been built in accordance with
the prior art as members containing a spiralling passage, with or
without changes of direction, said passage being excessively narrow
and, therefore, highly susceptible to be very frequently clogged by
foreign matter or by the deposition of salts, particularly so in
those places which are in the proximities of the liquid outlet,
where the solar or ambient heat evaporates the liquid and gradually
deposits salts which eventually completely obstruct said
passage.
In United States copending patent application Ser. No. 288,629
filed by the same applicant on Sept. 13, 1972, there is disclosed
and claimed a one-piece drip irrigation device which causes a
pressure drop in the liquid from the irrigation pipe by the
provision of a passage operating mainly by very frequent and sharp
changes of direction of the flow and by impact of the liquid on a
plurality of partitions or baffles, and which also partially solves
the above mentioned problem of clogging of the passage, in view of
the fact that said passage can be of a relatively large cross
section, whereby clogging of the same is minimized. Also, in the
CIP United States copending patent application Ser. No. 443,660
filed on Feb. 19, 1974 by the same applicant, there is shown and
described a modified drip irrigation device which operates under
the same above mentioned principles but which can be manufactured
in the form of a continuous strip or ribbon having spaced labyrinth
passages formed therein, said ribbon being attached to a drip
irrigation pipe having bores matching one of the ends of said
passages and the liquid being emitted through suitable slits or
bores placed at the opposite end of said passages. While the
devices described and claimed in the above mentioned copending
United States patent applications partially solve the problems of
clogging, the fact still remains that, if said drip irrigation
devices are clogged by the deposition of salts at the places near
the liquid outlets by evaporation of the liquid, or by the entrance
of foreign matter into some of the chambers formed in the
labyrinth, thereby obstructing the same, it will be impossible to
remove the clogs unless the devices are completely disassembled
from the drip irrigation pipes for cleaning purposes. In other
words, as the passages through which the liquid flows in this type
of devices are generally integrally adhered to the outer walls of
the drip irrigation pipes, it is not possible to unclog said
devices, which therefore greatly precludes the functionality
thereof.
BRIEF SUMMARY OF THE INVENTION
Having in mind the defects of the prior art drip irrigation valves,
it is an object of the present invention to provide an
anti-clogging drip irrigation valve of the labyrinth type, which
will solve all the problems of the prior art devices and will be of
a very simple and economic construction.
It is another object of the present invention to provide an
anti-clogging drip irrigation valve of the above mentioned
character, which can be used directly attached to a drip irrigation
pipe or as a separate unit engageable to a drip irrigation pipe to
serve as a disposable dropper.
It is a more particular object of the present invention to provide
an anti-clogging labyrinth type drip irrigation valve of the above
mentioned character, which will provide for the removal of any clog
which might be accidentally introduced within the labyrinth passage
thereof.
One more object of the present invention is to provide an
anti-clogging drip irrigation valve of the above mentioned
characteristics, which will be highly economical both as to its
fabrication and as to its use and which will not require of any
type of control to effectively work.
Still one more object of the present invention is to provide an
anti-clogging drip irrigation valve of the above mentioned
character, which can be manufactured in the form of a flexible
continuous ribbon or in the form of separate short elements, both
suitable to act in combination with a drip irrigation pipe having
suitable bores.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features that are considered characteristic of the
present invention are set forth with particularity in the appended
claims. The invention itself, however, both as to its organization
and its method of operation, together with additional objects and
advantages thereof, will best be understood from the following
description of specific embodiments when read in connection with
the accompanying drawings, in which:
FIG. 1 is a top plan view of a first embodiment of a drip
irrigation valve built in accordance with the present invention,
showing the face having formed therein a labyrinth shaped channel
and reception and emission cavities, with its complementary cover
member removed to show inner details;
FIG. 2 is an elevational cross sectional view taken along lines
2--2 of FIG. 1 and looking in the direction of the arrows, showing
the laminated structure of the valve in accordance with the present
invention, as well as a complementary cover member attached
thereto;
FIG. 3 is a cross sectional view taken along lines 3--3 of FIG. 1
and looking in the direction of the arrows, also showing the said
complementary cover member;
FIG. 4 is a side elevational view, partly broken away to show inner
details, of the device built in accordance with the first
embodiment of the present invention, together with a fluid supply
pipe to which it is associated;
FIG. 5 is a cross sectional view taken along lines 5--5 of FIG. 4
and looking in the direction of the arrows;
FIG. 6 is a view similar to FIG. 4, showing a second embodiment of
a drip irrigation valve built in accordance with the present
invention, in the form of a continuous ribbon having separate
labyrinth passages associated to respective bores of the
complementary pipe, and partly broken away to show inner details
thereof;
FIG. 7 is a bottom plan cross sectional view taken along lines 7--7
of FIG. 6 and looking in the direction of the arrows;
FIG. 8 is a view similar to FIG. 7, partly broken away to show
inner details thereof, and showing still another embodiment of a
drip irrigation valve built in accordance with the present
invention;
FIG. 9 is a cross sectional elevational view of a drip irrigation
valve built in accordance with the present invention, adhered to a
pipe formed by a pair of flexible sheets sealed together at their
edges;
FIG. 10 is a view similar to FIG. 9 but showing the drip irrigation
valve of the present invention adhered to the inner wall of the
pipe;
FIG. 11 is a view similar to FIG. 9 showing a drip irrigation valve
built in accordance with the present invention, as adhered to a
pipe formed by a flexible sheet sealed at the free edges
thereof;
FIG. 12 is an elevational cross sectional view of the device shown
in FIGS. 9 and 11, but showing the pipe already expanded by the
passage of liquid therethrough;
FIG. 13 is a fragmentary cross sectional perspective view showing
an embodiment of the drip irrigation valve in accordance with the
present invention, in combination with a pipe formed by an
overlapped sealed flexible sheet;
FIG. 14 is a cross sectional elevational view of a particularly
preferred embodiment of a drip irrigation valve built in accordance
with another embodiment of the present invention, in the form of a
disposable dropper or valve unit connected to a drip irrigation
pipe;
FIG. 15 is a cross sectional view taken along lines 15--15 of FIG.
14 and looking in the direction of the arrows;
FIG. 16 is a fragmentary cross sectional elevational view of an
additional embodiment of a disposable dropper or valve built in
accordance with the present invention, as connected at its upper
end to a bore provided at the lowermost portion of the associated
pipe; and
FIG. 17 is a fragmentary cross sectional elevational view of still
another embodiment of a disposable dropper or valve as connected to
a flexible tube which in turn can be connected at its free end to a
suitable fluid supply pipe.
DETAILED DESCRIPTION
Having now more particular reference to the drawings and more
specifically to FIGS. 1 to 5 thereof, there is shown a drip
irrigation valve built in accordance with a first embodiment of the
present invention, which is generally illustrated in said figures
by reference character 11, and comprises an elongated rectangular
relatively thick flat plate 14 of a highly flexible material,
preferably a plastic foam material having closed or isolated cells,
provided that it has compressible characteristics for a purpose
which will be more clearly apparent in the following description.
The plate 14 of flexible material can have flanges 15 at all its
four edges, for suitable engagement to a counterpart or
complementary member 12 (not shown in FIG. 1) and is covered at its
outer face by means of a laminated flexible film 13, in order to
suitably protect said plate against external agents, as well as to
reinforce the assembly to support fluid pressure.
At the opposite face, that is, at the face that will be attached to
the above mentioned counterpart 12, plate 14 of element 11 built in
accordance with the first embodiment of the present invention is
provided with a channel made in the form of a labyrinth by the
provision of a plurality of walls or upstanding partitions 20,
placed symmetrically and alternately within a cavity as clearly
shown in FIG. 1 of the drawings, to provide a fluid passage 21, a
reception chamber 18 at one end of said passage and an emission
chamber 19 at the other end of said passage for a purpose which
will be described in full detail hereinbefore. Passage 21 produces,
as indicated by the arrows shown in FIG. 1, a large number of sharp
changes of direction in the flow of the irrigation fluid, whereby
said fluid will suffer considerable pressure drop from the
reception chamber 18 to the emission chamber 19, in order to
provide a flow from the emission chamber 19 which will be very slow
and practically dropwise, such as is necessary in the drip
irrigation systems to which this invention refers.
The flexible nature of the material of plate 14, including the
partitions 20 forming the labyrinth passage 21 clearly illustrated
in FIG. 1 of the drawings, as well as the flexible nature of the
cover film 13, enable the device built in accordance with this
first embodiment of the invention to be squeezed either manually or
by means of a roller or the like, such that, if the labyrinth 21 be
obstructed, either by the deposition of salts from evaporated
liquid or by the introduction of debris therein, said obstruction
can be removed by squeezing said drip irrigation device, either
periodically in a maintenance-like manner or through specific needs
of removing clogging therefrom.
The device built in accordance with the illustrative embodiment
presently described, can be directly adhered to a rigid drip
irrigation pipe 12, such that a bore 17 provided in the wall
thereof will match the reception chamber 18 of the valve 11, to
receive the irrigation fluid which flows through the pipe 12 at a
predetermined pressure and to convey it through passage 21 formed
between the partitions 20 and the wall of pipe 12, in order to
reduce the pressure thereof to a predetermined value such that, at
the emission chamber 19, said liquid will have a highly reduced
pressure which will force it to flow very slowly, that is, in a
dropwise manner, through suitable outlet means such as a slit or an
orifice. In the particularly preferred embodiment of the present
invention said outlet means comprises a loose tongue section 115 of
flange 15 corresponding to the extremity of the emission chamber
19, such that a check valve 22 is formed, as illustrated in FIG. 4
of the drawings. As long as there is pressure within the emission
chamber 19, said check valve 22 will be opened by the flowing
liquid in order to permit the dropwise emission thereof. However,
when the flow of liquid through the pipe 12 ceases and certain
vacuum is applied to the emission chamber 19, the loose tongue 115
is forced to bear against the wall of pipe 12, thereby closing the
check valve 22 in order to prevent the back entrance of ambient
debris. The provision of this type of check valve 22 at the
emission chamber 19 of the valve 11 built in accordance with this
embodiment of the invention, which is rendered possible by the
flexibility of the material of plate 14, avoids the possibility of
clogging of passage 21 by the entrance of dirt or debris from the
surroundings when the flow of the irrigation fluid through the pipe
12 ceases and a partial vacuum is applied to the emission chamber
19 thereby otherwise enabling the sucking in of such dirt from the
environment. By the provision of the flexible loose tongue 115
adjacent the wall of the pipe 12 in accordance with the above, said
tongue 115 will act to provide a check valve 22, thus permitting
the emission of liquid from the emission chamber 19 but preventing
the entrance of foreign matter through said check valve 22, when
certain suction is applied to the chamber 19, inasmuch as, under
these conditions, the loose tongue 115 will be forced against the
wall of the pipe 12 and will completely close the check valve
22.
If in spite of the above, some dirt builds up in any portion of
passage 21 or in any of chambers 18 and 19 of the dropper or valve
11, then the flexibility of plate 14 provides the additional
possibility of squeezing the whole of the assembly 11 by means of
the fingers or by means of a roller or the like, to substantially
alter the shape of the valve 11, whereby the accumulated dirt will
be released and thrown out of the system through the check valve 22
in a suitable manner.
Such as will be clearly apparent to any one skilled in the art, the
valve or dropper device 11 built in accordance with the present
invention can adopt a diversity of shapes other than that
particularly and illustratively described in connection with FIG. 1
to 5 of the drawings. Therefore, in FIGS. 6 and 7 of the drawings
there is illustrated a valve 11 built in accordance with the
present invention, comprising a plate of highly flexible material
14 and a flexible cover film 13, but this illustrative embodiment
of the invention having the shape of a ribbon or continuous strip
with labyrinths 21 distributed throughout its length, with
respective reception and emission chambers 18 and 19, said
labyrinths being spaced from each other by solid intermediate
blocks 24, and said ribbon-like plurality of valves 11 being built
by means of a pair of side vertical walls 23 and a plurality of
partitions 20 which force the fluid to change direction in its flow
through the passage 21 such as it can be clearly seen in FIGS. 6
and 7 of the drawings. In the particular case of a multiple dropper
or valve device 11 having the shape of a continuous ribbon built in
accordance with the presently described embodiment, high reductions
in labor cost can be achieved in view of the fact that this device
can be previously attached to a pipe 12, previously providing bores
17 suitably distributed throughout the length of said pipe,
matching the respective reception chambers 18 of each labyrinth 21
and leaving a section of the wall of pipe 12 loosely attached to a
tongue section of the side wall portions 23, to form the check
valve also designated by reference character 22 in FIGS. 6 and 7 of
the drawings, so that the emission chambers 19 will discharge
through said sidewardly provided check valve 22, such as previously
described in connection with FIGS. 1 to 5 of the drawings. The
performance of the continuous ribbon-like dropper or valve 11 is
exactly the same as that described for the individual valve
elements 11 illustrated in FIGS. 1 to 5 of the drawings, whereby it
is considered unnecessary to go into any further detail in
connection therewith.
As it will be obvious to any one skilled in the art, the dropper or
valve device 11 of the present invention, either built in the form
of separate elements or patches such as those of FIGS. 1 to 5, or
in the form of a continuous ribbon-like multiple element such as
that of FIGS. 6 and 7, can be provided with passages 21 in the form
of labyrinths having different designs, such as more particularly
illustrated in FIG. 8 of the drawings. In said figure it can be
seen that in accordance with a third embodiment of the present
invention, a continuous ribbon-like element is provided, for
instance, comprising a pair of side walls 23 and dropper-spacing
blocks 24 along the length of the ribbon, and reception and
emission chambers 18 and 19 both located at the central portion of
said dropper or valve 11, the latter being attached to pipe 12 such
that the bores 17 provided in the said pipe, will match
corresponding reception chambers 18.
The labyrinth passage 21 is formed between said side walls 23 and a
longitudinal central baffle 25 provided with a plurality of
transverse partitions 26 staggered with a corresponding plurality
of partitions 20 projecting from each one of said side walls 23. An
emission chamber 19 is provided at the end of the path of the above
mentioned labyrinth, a portion of the side wall 23 bounding said
chamber 19 being loosely engaged to the wall of pipe 12, such as
illustrated at 22, in order to form the above described check valve
which permits the dropwise discharge of the fluid but prevents the
backflow of debris into the device.
In the particular case of the embodiment of FIG. 8, the irrigation
liquid enters through opening 17 of the pipe, passes to the central
reception chamber 18 of the dropper or valve 11, flows towards the
left as illustrated in FIG. 8 along one side of the central baffle
25, then back towards the right along the opposite side of baffle
25 and then again back towards the left along the one side of said
baffle 25 to the central portion of the dropper 11 to be discharged
through the emission chamber 19 which is adjacent the reception
chamber 18.
It will also be obvious to any one skilled in the art that great
variations of the structures and designs of the labyrinths formed
within the droppers or valves 11 built in accordance with the
present invention are possible, but all such modifications must be
construed as embodied within the true scope and spirit of the
present invention, inasmuch as the manner of building such
labyrinths is irrelevant as long as the material forming the plate
14 with its partitions be highly flexible to enable full squeezing
thereof to release clogs from passage 21, and as long as the outlet
means for the liquid from the emission chamber be preferably
provided by a check valve formed by the loose portion of the side
wall of said chamber, which permits opening of said portion when
there is pressure within the emission chamber but prevents the
entrance of foreign matter when a certain vacuum is applied
thereto.
FIGS. 9 and 10 of the drawings illustrate a dropper or valve device
11 in accordance with any embodiment of the present invention, in
combination with a pair of flexible sheets 27 sealed at their edges
as shown at 28, in order to form a pipe which, once inflated by the
passage of the fluid, would remain approximately in the disposition
shown in FIG. 12 of the drawings. The arrangement of the openings
17 in one of the flexible sheets 27 of the pipe 12 will be such
that they match the reception chambers of the labyrinths 21 of the
valves 11. Also, the valve 11 can be arranged either inside (FIG.
10) or outside (FIG. 9) of the pipe, indistinctly. When inside, the
fluid entrance means 22 will be provided by a bore as shown in FIG.
10.
The valve 11 of the present invention can also be applied to a pipe
made of a single flexible sheet 27 such as illustrated in FIG. 11
of the drawings, the side edges of said sheet being sealed together
as shown at 28, the dropper 11 working in combination with the thus
formed pipe 12, once the latter has been inflated by the fluid,
such that it will be arranged as shown in FIG. 12 of the
drawings.
Still another embodiment of the association of a dropper or valve
11 and liquid supply pipe 12 in accordance with the present
invention is illustrated in FIG. 13 of the drawings, wherein the
valve 11 is attached on the outside or on the inside of a pipe 12
formed by a single plastic sheet sealed at its ends such that said
ends are overlapped as illustrated at 29.
It will thus be seen that the dropper or valve device 11 in
accordance with the embodiments shown in FIGS. 9 to 13 of the
drawings, as provided either on the inside or on the outside of at
least one flexible sheet which will thereafter form the pipe 12,
enables plant production of a complete prefabricated drip
irrigation unit having a pipe and a plurality of droppers, ready to
be used in the field and easily transportable while in a folded
condition. The deformable characteristics of both the flexible
sheet forming the pipe 12 in accordance with FIGS. 9 to 13 of the
drawings and of the plate 14 of the droppers or valves 11, besides
providing fully foldable and easily handled units, also fully
provide for removal of clogs from the droppers, in order to provide
a controlled, continuous and efficient performance thereof.
The valve or dropper device in accordance with the present
invention can adopt a highly preferred form which will be described
hereinafter in connection with the embodiments shown in FIGS. 14 to
17 of the accompanying drawings, in which said dropper or valve is
illustrated as an independent disposable unit 10. The unit dropper
or valve 10 comprises a relatively thick plate 14 built with a
highly flexible material such as a plastic foam having separate or
closed cells, said plate being provided with side flanges 15, if
desired and having laminated thereto a flexible cover sheet 13, on
one of its faces, the channel 21 in the form of a labyrinth being
provided, as previously described, by the projecting partitions 20.
The valve or dropper 10 according to the particularly preferred
embodiment of this invention is completed by attaching to the
opposite face of plate 14, an additional flexible sheet 30, thereby
forming a closed structure having a labyrinth passage 21, a
reception chamber 18 and an emission chamber 19 with the tongue 115
at the end of sheet 30 to provide the check valve 22 as shown in
FIG. 14.
The disposable unit valve 10 can be used in a diversity of manners
and thus, as clearly illustrated in FIG. 14 of the drawings, said
disposable unit can be provided with a short tubular connector 31
which has supporting flanges 33 provided within the reception
chamber 18 of the valve 10, and flanges 32 provided at the opposite
end of the connector 31 to be introduced with pressure fit through
the corresponding opening 17 of the drip irrigation pipe 12 so as
to seal such connector 31 in a fluid tight manner to the opening 17
sidewardly provided in pipe 12.
The unit valve 10 in accordance with FIG. 14 can be used as an
underground device, with part thereof buried, inasmuch as the
provision of the check valve 22 will prevent any backflow into
chamber 19, thereby also avoiding the introduction of debris and
the like into the passage 21.
When the efficiency of the drip irrigation valve of the invention
is reduced by prolongued use or by mistreatment, then said valve
may be easily replaced, inasmuch as the valve 10 built in
accordance with this embodiment of the invention is a very low cost
disposable unit.
As a slightly modified embodiment of the disposable valve 10
illustrated in FIGS. 14 and 15, the reception chamber 18 of said
valve can be provided, at its upper end, with an integral connector
31 sealed to the end wall of the reception chamber 18 as
illustrated in FIG. 16 of the drawings, said connector 31 having a
flange 32 to be inserted with a pressure fit through an opening 17
of a drip irrigation pipe 12, thereby providing a fluid tight joint
between the disposable valve 10 and the opening 17 of the drip
irrigation pipe. In this particular case, the valve 10 will be
connected to bores provided at the lowermost section of the pipe
12.
As an additional embodiment of the disposable dropper or valve 10,
said valve can be provided with an opening 35 at its upper end
corresponding to the reception chamber 18, within which a flexible
tube 34 is engaged with a pressure fit, said flexible tube being
connected to a distribution manifold as commonly used in connection
with drip irrigation piping systems.
From the above it can be seen that there has been provided a
dropper or valve device for drip irrigation systems which is highly
versatile inasmuch as it can be attached to any type of
complementary surfaces. For instance, it can be directly attached
to a drip irrigation rigid pipe by the provision of opening in said
pipe matching the reception chambers of each dropper or valve. The
above mentioned dropper or valve can be built as separate elements
or patches which can be attached to the pipe either colinearly or
in circumferentially spaced positions in order to longitudinally
overlap the same to shorten the distances between the openings of
the pipe. The valves can also be built in the form of a continuous
ribbon having a plurality of valves, which is attached along the
rigid piping. The device of the present invention can also be
attached either on the inside or on the outside of at least one
flexible pipe-forming film which edges are sealed together in any
known manner in order to form a flexible drip irrigation pipe which
will integrally contain a plurality of droppers or valves evenly
distributed along the same. Finally, the dropper or valve in
accordance with the present invention can constitute a separate
disposable self-controllable drip irrigation valve unit, which can
be connected by means of suitable connectors either to a drip
irrigation pipe or to a flexible distribution pipe corresponding to
a fluid distribution manifold.
Although certain specific embodiments of the present invention have
been shown and described, it is to be understood that many
modifications thereof are possible. The present invention,
therefore, is not to be restricted except insofar as is
necessitated by the prior art and by the spirit of the appended
claims.
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