GB2083993A

GB2083993A - An irrigation device

Info

Publication number: GB2083993A
Application number: GB8127287A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-09-18
Filing date: 1981-09-09
Publication date: 1982-04-07
Also published as: NO149907C; GB2083993B; NO149907B; SE8105439L; SE448336B; NO813004L; DK152822C; DK152822B; DK395480A

Abstract

The irrigation device comprises a receptacle (5) supplied with water. A float (6) with a siphon (12) is located above outlet (13), one branch pipe (11) of said siphon extending through a portion (10) in the bottom of the float. The pipe (11) carries at its lower open end a valve (7) which may close tightly against a surface (8) in the bottom of the receptacle (5). A closing pipe (9) projects from the surface (8) about the pipe (11) and forms together with the bottom portion (10) of the float a siphon connection between the receptacle (5) and the outlet (13). Within the receptacle (5) the water raises the float until the valve (7) closes against the surface (8), and the water rises beyond the top rim of the float until the water within the float has reached a level (C-C) at which the weight of the water with the float surmounts the buoyancy in the receptacle (5). The connection to the outlet (13) is thus opened, and the water is quickly sucked out through the siphon connection at the underside of the float and produces a sucking effect within the siphon (12) so that the float (6) is emptied. Clogging deriving from deposits and a slow leaking out of water through the siphon are avoided due to the quick irrigation and to the fact that stagnant water is never present at the elbow of the siphon. <IMAGE>

Description

SPECIFICATION An irrigation device The invention relates to an irrigation device com- prising a receptacle with an inlet in the upper portion for introduction of an adjustable amount of water and a bottom outlet for a quick emptying of a volume of water collected in the receptacle.

Such an irrigation device permits a constant and uniform irrigation and preferably also a fertilization of plants in hot-houses, winter gardens, at terraces and the like places, where the irrigation may be performed by means of a simple system of flexible hoses provided with apertures opposite the plants to be irrigated. In such an irrigation system it is important that the flexible hoses at regular intervals are filled quickly and completely with water in such a manner that the system supplies almost equially high amounts of water through the apertures located both firstly and finally in the flow direction of the hoses.The use of a receptacle with a simple siphon outlet may indeed produce a quick emptying of the receptacle when the surface of the water therein rises above the elbow of the siphon, but in practise it turned out that the slowly rising water surface implies that calcarous deposits appear within the siphon pipe immediately above the elbow. These calcarous deposits may imply that water is slowly sucked into the branch pipe of the siphon forming the outlet, and gradually the deposits form a narrowing preventing a quick emptying of the receptacle. In both cases, the plants adjacent the irrigation device are watered too much and the plants remotely placed relative to the device are watered too poorly.

The use of a siphon pipe of a very large diameter implies the risk that a not unsubstantial amount of water flows away above the elbow at the underside of the siphon pipe before the siphon effect ensuring a quick emptying occurs.

The object of the present invention is to provide an irrigation device of the above art, which avoids the above drawbacks in such a manner that even after use of the device for a long time, no risk of waste of water or of an excess irrigation of the plants adjacent the device and of a too poor irrigation of the plants remotely placed relative to the device occurs.

The irrigation device according to the invention is characterised in that it comprises a cup-shaped float located above the bottom outlet in the receptacle and in which a siphon is located, the elbow of which is situated above the highest level of the surface within the float, and one branch pipe of which ends at the bottom of the float, and the second branch pipe of which extends through the upper closed end surface of a tubular upright portion of the bottom of the float, the lower end of said second branch pipe ending at and carrying a valve body, which in an uppermost position of the float closes a path between the bottom outlet and a closing pipe projecting upwards from the bottom of the receptacle and surrounding the branch pipe projecting from the bottom of the float, and which together with the tubular portion of the bottom of the float form a siphon communicating freely under the bottom of the float with the portion of the receptacle surrounding said float, said closing pipe extending beyond the surface level within the receptacle, at which the buoyancy is greater than the weight of the float.

In such an irrigation device a quick and complete periodical emptying of both the receptacle and the float is always ensured, since no siphon elbow is present permitting a slowly rising water surface to deposit lime or a slowly overflowing before the siphon effect takes place. The valve body keeps the outlet closed until the water within the float has reached a level a short distance below the elbow of the siphon, and the subsequently following downward movement of the float opens the valve and the water within the receptacle leaves quickly through the siphon formed at the bottom of the float. As a result, a sucking is produced within the siphon in the float whereby the water therein quickly rises to the elbow of the siphon and the float is emptied.

A sufficient sucking within the siphon in the float for producing the siphon effect may according to the invention be easily obtained by the valve body being conical and located about the projecting branch pipe of the siphon in such a manner that said branch pipe ends at the lower point of the valve body, whereas the upper circular rim of the valve body is adapted to abut a conical closing surface, which at its upper narrow end extends into the closing pipe projecting from the bottom of the receptacle.

For adjusting the intervals between the emptyings and consequently the watering intensity, the inlet of the receptacle is according to the invention connected with a flowmeter connected to a pressure water conduit, in which a pressure compensating flow-regulating valve is located.

For the supply of liquid fertilizers in a constant proportion to the amount of water a closed fertilizer container may according to the invention be provided which comprises an outlet pipe stub turning downwards and through an adjustable length thereof being immersed in a reservoir located above the receptacle, in the bottom of which a filter is located, through which fertilizers may pass dropwise in an amount determined by the pressure above the filter. In this manner a simple regular watering with a constant fertilizer content in the water is obtained.

In orderto counteract an irregular water supply owing to a fluctuating pressure in the water supply conduit in a simple and inexpensive manner, the pressure compensating flow-regulating valve may according to the invention comprise a sleeve located within a cylindrical valve housing and being axially compressible through a regulating spindle, the interior of said sleeve communicating with the water supply conduit, and the wall of said sleeve together with the surrounding valve housing forming an outlet path, which is variable and may be closed, respectively, through bending of said wall, and which through radial bores in said wail at the centre of the sleeve communicates with the interior of said sleeve.When the pressure within the water supply conduit and consequently within the interior of the sleeve increases, the wall of the sleeve curves outwards towards the valve housing and thereby defines the flow area and vice versa.

The invention will be described below with reference to the accompanying drawing, in which Fig. lisa cross sectional view through an embodiment of the irrigation device according to the invention, and Figs. 2 and 3 illustrate an embodiment of a pressure compensating flow-regulating valve for the irrigation device according to the invention in the closed and open position, respectively.

The irrigation device illustrated comprises a receptacle 5 for instance made of plastics. At the top the receptacle is on the outside shaped with a regulating reservoir 2, the transparent wall of which is provided with a scale 3 indicating the surface level of water flowing through an adjustable valve 1. From the reservoir 2, the water flows into the receptacle 5 through a flow channel 4. The reservoir 2 thus serves as a flowmeter indicating the amount of inflowing water. For compensation of changes of pressure within the water supply conduit the adjusting valve 1 can in a simple manner be formed as a pressure compensating flow-regulating valve, cf. below.

The receptacle 5 furthermore comprises a cupshaped bottom outlet 13 for the connection of a flexible hose. The wall of this flexible hose is at regular intervals provided with outlet apertures opposite the plants to be irrigated. A cup-shaped float 6 is located above the outlet 13. In the bottom position this cupshaped float 6 rests on spacer projections 14 or corresponding projections in the bottom of the float or the receptacle in such a manner that the water in the receptacle 5 has free access to the underside of the float. The bottom of the float is shaped with a central, upright, tubular portion 10, a connecting pipe 11 extending through the closed end surface of said tubular portion. The connecting pipe forms the lower part of one branch pipe of a siphon 12, the opposite end of which ends in the bottom of the float.At its lower end the connecting pipe 11 comprises a conical valve body 7, the upper circular rim of which forms a stop defining the upward movement of the float as it sealingly abuts a conical closing surface 8 in the bottom ofthe receptacle 5. In the illustrated intermediary position and in the bottom position as well, a free connection is present between a closing pipe 9 projecting from the receptacle and the outlet 13. The connecting pipe 11 of the siphon ends as shown in the point of the valve body 7.

The closing pipe 9 and the tubular portion 10 form a siphon connection between the receptacle 5 and the outlet 13. The siphon effect occurs when the water surface within the receptacle 5 is at a higher level than the orifice of the closing pipe 9, whereby the valve 7 is opened.

When water from the flow channel 4 flows into the empty receptacle 5, the float 6 rests on the spacer projections 14 until the water surface has reached a predetermined level A-A situated below the orifice of the closing pipe 9. Subsequently, the buoyancy is sufficiently great for raising the float 6 until the valve body 7 closes against the closing surface 8. Now the float is in the position indicated by dotted lines, and the water continues to rise to the illustrated level B-B and then flows into the float 6. When the water in the float has reached a level C-C art a distance below the elbow of the siphon 12, the weight of the float surmounts the buoyancy in the receptacle 5 whereby the float 6 moves downwards.In this manner the path between the valve body 7 and the closing surface 8 is opened, and the water from the receptacle 5 leaves through the outlet 13 owing to the siphon effect and at a velocity being far higher than the velocity at which the water enters the float 6 at the top.

The liquid surface within the receptacle 5 immedi atelydecreases below the top rim of the foat 6, whereby the water supply to said float stops. The heavy flow of water about the valve body 7 produces a sucking in the connecting pipe 11, which implies an activation of the siphon 12 and a quick emptying of the float 6. As it appears stagnant water is never present at the elbow of the siphon 12, and consequently calcarous deposits forming a narrowing or a slow sucking of water from one branch of the siphon to the other are avoided. Similarly a corresponding unfortunate effect cannot occur at the siphon formed under the bottom of the float 6. The irrigation device therefore operates in a reliable manner even after use for a long period. Furthermore, it supplies quickly and at adjustable intervals a large amount of water.

The receptacle 5 is provided with a cover 20, in which a reservoir 17 for liquid fertilizers is formed. A closed fertilizer container 15 is located on top of the reservoir 17 and comprises an outlet pipe stub 16 immersed in said reservoir and thereby determining the surface level therein. A resistance filter 18 is located in the bottom of the reservoir, and fertilizers can pass dropwise through said filter in an amount determined by the pressure above the filter. The liquid pressure at the bottom of the reservoir 17 and consequently the amount of fertilizers supplied the filter 18 can be adjusted by changing the height of the container 15 and consequently the immersing length of the pipe stub in the reservoir. For this purpose the container 15 is supported on the cover by means of a level ring 19 replaceable by rings of other heights.It is to be understood, that the adjustment of the height of the fertiliser container 15 may also be carried out in other ways, e.g. by means of a screw connection between an extension pipe and the pipe stub 16 or between the container 15 and the cover 20. A desired concentration of fertilizers in the water supplied from the irrigation device can be obtained by adapting the adjustment of the height of the ferlilizer container 15 to the water flowing to the receptacle 5 adjusted by means of the adjusting valve 1.

The adjusting valve 1 may as previously mentioned be adapted to compensate for fluctuationsin the pressure within the water supply conduit in such a manner that the interval between the emptyings of the receptacle 5 remains constant in spite of such fiuctuations. A simple embodiment of a such a pressure compensating flow-regulating valve is illustrated in Figs. 2 and 3, in which the valve appears in the closed and the open position, respectively.

The adjusting valve 1 illustrated comprises a cylindrical valve housing 21, in which a sleeve 22 of resilient material is located. One end of the sleeve tightly abuts a regulating spindle 23, the opposite end thereof communicating with a water supply conduit 24. At the centre of the sleeve, its wall comprises a plurality of radial bores 25, through which the water supply conduit 24 is connectable with the outlet pipe stub 26 of the valve. When the sleeve 22 is subjected to an axial pressure by the regulating spindle 23, its wall curves outwards towards the housing 21 and therby defines the path between the pipe 24 and the outlet pipe stub 26, and optionally closes said path completely, cf. Fig. 2.When the valve is completely or partiaily open and the wall of the sleeve 22 is cylindrical or only curves slightly outwards, an increasing pressure in the water supply conduit 24 and consequently in the interoir of the sleeve causes an increasing bulging outwards of the wall and a corresponding defining ofthe water flow, whereby an increased water supply owing to the increasing pressure is counteracted. Conversely, a drop in pressure in the water supply conduit 24 implies that the wall of the sleeve curves less in such a manner that the flow area is increased and thereby counteracts a reduced water supply owing to the dropping pressure.

It is to be understood, that various modifications may be carried out within the sope of the invention.

The valve body 7 and the orifice of the connecting pipe 11 at the valve body may for instance be shaped in other ways ensuring an efficient closing of the outlet 13 and a sufficiently heavy sucking so that the siphon 12 enters into function when the water flows out of the receptacle 5.

Claims

1. An irrigation device comprising a receptacle with an inlet in the upper portion for introduction of an adjustable amount of water and a bottom outlet for a quick emptying of a volume of water collected in the receptacle, characterised in that it comprises a cup-shaped float located above the bottom outlet in the receptacle and in which a siphon is located, the elbow of which is situated above the highest level of the surface within the float, and one branch pipe of which ends at the bottom of the float, and the second branch pipe of which extends through the upper closed end surface of a tubular upright portion of the bottom of the float, the lower end of said second branch pipe ending at and carrying a valve body, which in an uppermost position of the float closes a path between the bottom outlet and a closing pipe projecting upwards from the bottom of the receptacle and surrounding the branch pipe projecting from the bottom of the float, and which together with the tubular portion of the bottom of the float form a siphon communicating freely under the bottom of the float with the portion of the receptacle surround-.

ing said float, said closing pipe extending beyond the surface level within the receptacle, at which the buoyancy is greater than the weight of the float.

2. An irrigation device as claimed in claim 1, characterised in that the siphon branch pipe projecting from the bottom of the float extends through a substantially conical valve body and ends in the point turning downwards thereof, and that the valve body through its upper circular rim abuts a conical closing surface, which at its uppermost, narrowest end ends in the lower end of the closing pipe.

3. An irrigation device as claimed in claims 1 and 2, characterised in that the inlet of the receptacle is connected with a flowmeter connected to a pressure water conduit, in which a pressure compensating flow-regulating valve is located.

4. An irrigation device as claimed in any one of the preceding claims and comprising dosage means for the addition of liquid fertilizers into the water within the receptacle, characterised in that the dosage means are formed by a closed fertilizer container with an outlet pipe stub turning downwards and through an adjustable length thereof being immersed in a reservoir located above the receptacle, in the bottom of which a filter is located, through which fertilizers may pass dropwise in an amount determined by the pressure above the filter.

5. An irrigation device as claimed in claim 3, characterised in that the pressure compensating flow-regulating valve comprises a sleeve located within a cylindrical valve housing and being axially compressible through a regulating spindle, the interior of said sleeve communicating with the water supply conduit, and the wall of said sleeve together with the surrounding valve housing forming an outlet path, which is variable and may be closed, respectivley, through bending of said wall and which through radial bores in said wall at the centre of the sleeve communicates with the interoir of said sleeve.

6. An irrigation device substantially as described above and with reference to the accompanying drawing.