GB2074833A - Supplying liquid to constant level in containers - Google Patents

Abstract

An apparatus 1 for maintaining a desired level of liquid in a liquid container 3 by gravity flow from a closed non-collapsing reservoir 2 for the liquid. A liquid supply pipe 4 extends from the reservoir to the liquid container, and an air inlet pipe 5 extends from a point in said reservoir above the level of liquid intake to said supply pipe and terminating above the outlet of said supply pipe at or adjacent to the intended level of liquid in said liquid container. Liquid from the reservoir fills the liquid container until the level of liquid reaches the level of the air inlet pipe. Air cannot be drawn into the reservoir, so that liquid ceases to flow out from it. If the liquid level falls air can enter through the air inlet pipe until the liquid level is again proximate the level of the air inlet pipe. <IMAGE>

Description

SPECIFICATION Apparatus for controlling the supply of a liquid This invention relates to apparatus for controlling the supply of a liquid to a liquid receiving container and in particular though not exclusively to apparatus for providing a constant water level to a plant pot waterer.

There has long existed the problem of supplying water to plants, pets, small livestock, poultry etc whilst their owners are not present to attend to them e.g. while the owners are on holiday. Green house plants, seedlings etc need adequate supplies of water throughout the day, and house plants can easily be forgotten and left unattended for long periods of time.

A well known method for continually supplying water to some desired receptacle involves filling a container with water, inverting the container while covering its mouth and placing the inverted container in the desired receptacle. Water will then flow out of the container until the water level in the receptacle covers the mouth of the container. Should the water level in the receptacle fall water will then flow from the container into the receptacle until the water level rises above the mouth of the container. Although this method is well known it clearly has many disadvantages.

These include the likely spillage of water during the inversion of the container, the need for the water container to be in close proximity to the receiving receptacle, and the generally limited capacity of the container can have while still being managable. Thus it is an object of the present invention to provide apparatus for the continual supply of water, which can either be integral with proximate, or remote from the receptacle which is to receive the water, which is simple to use, which avoids the spillage of water, and can provide a sustained supply of water over a substantial length of time.

Thus according to the invention there is provided apparatus for maintaining a desired level of liquid in a container by gravity flow from a reservoir, comprising a closed non-collapsing reservoir for said liquid, a liquid container, a liquid supply pipe from said reservoir to said liquid container, and an air inlet pipe extending from a point in said reservoir above the level of liquid intake to said supply pipe and terminating above the outlet of said supply pipe at or adjacent to the intended level of liquid in said liquid container.

In a preferred embodiment of the invention the liquid supply pipe is so formed that liquid may be drawn from said reservoir by syphonic action.

In another preferred embodiment the reservoir is so formed as to be at least part of at least a wall of the liquid container.

To more clearly illustrate the invention two preferred embodiments thereof will now be described wherein the liquid to be supplied is water. It will be understood that liquids other than water may be used in conjunction with these preferred embodiments.

The two preferred embodiments of the invention will now be described by way of example and with reference to the accompanying drawings wherein: Figure 1 is a front view of an apparatus for controlling the supply of water according to the invention; Figure 2 is a section on the line A-A of Figure 1; Figure 3 is across sectional side view of a "plant pot waterer" according to the invention; and Figure 4 is a plan view of the Figure 3 embodiment of the invention.

Referring to Figures 1 and 2 of the drawings an apparatus 1 for controlling the supply of water according to a preferred embodiment of the invention generally comprises a closed reservoir 2, a water container 3 for receiving water from the reservoir 2, and a water supply pipe 4 and an air inlet pipe 5 which extend from within the reservoir 2 into the water container 3.

The reservoir 2 is preferably made of a rigid material and is provided with an air tight filler cap 6 which may be removed in order to fill the reservoir with water. The water supply pipe 4 generally commences as of an inverted U-shape, with the arm outside of the reservoir 2 the same length or longer than the internal arm and preferably provided with a tap 7. The external arm of the supply pipe 4 extends substantially into the water receiving container 3. The air inlet pipe 5 generally commences as an inverted L-shape with one arm extending into the reservoir above the arch 8 of the supply pipe 4, and the other arm terminating in the water receiving container 3 at a predetermined level above the end of the water supply pipe 4. There is a small chamber 10 at or near the end of the air inlet pipe 5.The water receiving container 3 may be any desired receptacle e.g. a green house irrigation tray, a pets water dish or a poultry water trough, which is to have a substantially constant water level maintained in it. The water receiving container 3 may be on the same level as reservoir 2 or on a lower level.

The reservoir 2 is preferably provided with a water level indicating tube 9 which has one end connected to the reservoir near its base, extends upwards generally parallel to the reservoir, and has its other end connected to the reservoir above the top of the arch 8 of the water supply tube 4 and below the level of the internal arm of the air inlet pipe 5. The indicating tube is so arranged that water in the reservoir will flow freely between it and the reservoir, thus, as known per se, giving a visual indication of the water level of the water level in the reservoir.

In use the filler cap 6 is removed, with tap 7 closed, and the reservoir is partially filled with water. The reservoir is filled so that the water level is above the top of the arch 8 of the water outlet tube and below the level of the internal arm of the air inlet pipe. Although this may be judged by comparing the relationship between the level of water in the indicator tube 9 and the levels of entry of the water supply pipe 4 and the air inlet pipe 5 into the reservoir some suitable indication is preferably provided on the indicator tube 9. When the reservoir has been filled to the desired level the airtight filler cap 6 is replaced. The reservoir is then placed in its desired location with the external ends of the supply pipe 4 and the air inlet pipe 5 positioned in the water receiving container 3 as herein before described.

If the water level is above the arch 8 of the supply tube 4 when the tap 7 is turned on water will flow out of the reservoir, via the supply pipe 4, into the water receiving container 3. As water leaves the reservoir 2 air is drawn into the reservoir 2 via the air inlet tube 5. Water will continue to pass into the water receiving container 3 until the water level becomes proximate with the end of the air inlet pipe 5. When the water reaches this level air cannot be drawn into the reservoir, and therefore, water ceases to flow from the reservoir into the water receiving container 3.

Should water be removed from the water receiving container 3 the water level will drop and the end of the air inlet tube 5 will become open to the atmosphere. Air can then enter the reservoir 2 and water can flow out of the reservoir into the water receiving container 3 until the water level again rises to cover the end of the air inlet tube 5.

It will be understood that this process is continuous if only small amounts of water are continually drawn off from the water receiving container 3, and that only if a substantial amount of water is removed from the water receiving container 3 over a short period of time will there be a noticeable drop in the level of water in the water container 3. The chamber 10 in the air inlet tube 5 substantially prevents small quantities of water being drawn up the air inlet tube.

Provided, as hereinbefore described, that the external end of the water supply tube 4 is at the level of or at lower level than its internal end, then as the level of water in the reservoir falls below the arch 8 of the outlet tube 4 water will continue to be drawn out of the reservoir through the outlet tube 4 by syphonic action.

The water container 3 does not have to be directly adjacent to or below the reservoir 2. If, for example, the water supply pipe 4 and air inlet pipe 5 have flexible portions the water container 3 may placed at some distance from the reservoir 2 provided that their relative levels are maintained as hereinbefore described. This feature will be of particular use if, there is limited space in the desired location of watering apparatus. For example if the apparatus were to be used for watering plants in a greenhouse the reservoir could be placed outside and only the water supply pipe and the air inlet pipe need be inside the greenhouse.

Referring now to Figures 3 and 4 of the drawings, a second embodiment of the invention is incorporated in a plant pot waterer 20 which generally comprises a hollow cylindrical closed reservoir 21 which is mounted on a base plate 22, a water supply pipe 23 and an air inlet pipe 24.

The closed reservoir 21 is water tightly mounted on the base 22. The base 22 has a raised central portion 25. The inner wall of the reservoir 21 and the raised central portion of the base 25 thus defined an annulus 32. The water supply pipe 23 is generally L-shaped, with one arm extending inside the reservoir and with the other arm extending radially through the internal wall of the reservoir into the annulus 32. The air inlet pipe 24 is generally L-shaped with one arm extending inside the reservoir from near to the top of the reservoir to a portion below the top of the central raised portion 25, and above the outlet of the water supply pipe.

The reservoir 21 is provided with an airtight filler cap 26 which has a rod 27 extending downwards into the reservoir and terminating inside the internal end of the water supply pipe 23. A ball valve 28 comprising a ball 34 and spring 30 is mounted inside the internal arm of the water supply pipe 23. Capillary matting or comparable material 29 extends over the central raised portion 25 and into the annulus 32.

In the use the airtight filler cap 26 is removed and the rod 27 is thus withdrawn from the internal arm of the water supply pipe 23. The ball is thus urged by the spring 30 against fianges 31 of the internal arm of the water supply pipe 23. The reservoir is then filled with water. Water cannot pass out of the water supply pipe 23 since it is sealed off from the reservoir by the ball valve 28.

The airtight filler cap 26 is replaced and the rod 27 pushes the ball 34 down inside the internal arm of the water supply pipe 23. Water can thus pass from the reservoir into the annulus 32. As water passes into the annulus 32 air is drawn into the reservoir via the air inlet pipe 24. When the water level rises to cover the end of the air inlet pipe 24 air can no longer enter the reservoir 21 and water thus ceases to flow into the annul us 32. A plant pot 33 is then placed into the plant pot waterer 20 so that the base of the plant pot 33 rests on the central raised portion 25. Material in the plant pot 33 will absorb water from the capillary matting 29, water will then be drawn by the capillary matting from the annulus 32 resulting in a drop of the water level therein. The end of the air inlet pipe 24 will thus become exposed to the air, and air can then enter the reservoir 21 and water pass from the reservoir 21 into the annulus 32. Water will continue to enter the annulus 32 until the water level again covers the end of the air inlet pipe 24. The water level in the annulus 32 is thus kept substantially constant.

If it is desired to refill the reservoir 21 the air tight filler cap 26 is removed and the ball valve 28 closes stopping any water remaining in the reservoir from passing into the annulus 32. When the air tight filler cap 26 is replaced the rod 27 depresses the ball valve 28 and water can then flow into the annulus 32. The rod and ball valve assembly thus prevents the flooding of the plant pot waterer 20 during filling of the reservoir 21.

Although the embodiment described with reference to the drawings of the plant pot waterer only provides space for one plant pot it will be readily seen that the invention may be embodied in a plant pot waterer of any desired shape and size.

By merely reshaping the reservoir 21 and omitting the raised central portion 25 the invention can be embodied in, for example, a dog watering bowl or a poultry waterering trough.

Claims (14)

1. Apparatus for maintaining a desired level of liquid in a container by gravity flow from a reservoir, comprising a closed non-collapsing reservoir for said liquid, a liquid container, a liquid supply pipe from said reservoir to said liquid container, and an air inlet pipe extending from a point in said reservoir above the level of liquid intake to said supply pipe and terminating above the outlet of said supply pipe at or adjacent to the intended level of liquid in said liquid container.

2. The apparatus as claimed in claim 1 wherein the liquid supply pipe is so formed that liquid may be drawn from said reservoir by syphonic action.

3. The apparatus as claimed in claims 1 or 2 wherein a liquid level indicating means is provided and arranged to give a visible indication of the liquid level in the reservoir.

4. The apparatus as claimed in claim 1,2 or 3 wherein a tap means is provided in the liquid supply pipe so that flow of liquid from the reservoir via the liquid supply pipe may be controlled.

5. The apparatus as claimed in any preceding claim wherein the air inlet pipe has a chamber formed in it, near to the end which terminates in the liquid container, so as to substantially prevent liquid from being drawn up the air inlet pipe into the reservoir.

6. The apparatus as claimed in any preceding claim wherein the reservoir is fitted with an airtight removable filter cap.

7. The apparatus as claimed in any preceding claim wherein the air inlet pipe and/or the water supply pipe have flexible portions so that the liquid container need not be placed directly beneath the reservoir.

8. The apparatus as claimed in Claim 1 or 2 wherein said reservoir is so formed as to be at least part of at least a wall of the liquid container.

9. The apparatus as claimed in claim 8 wherein a wall of the liquid container is adapted to receive an article which is to be supplied with liquid.

10. The apparatus as claimed in claim 8 or 9 wherein the base of the liquid container has at least one raised portion adapted to support an article which is to be supplied with water.

11. The apparatus as claimed in claim 9 wherein the raised portion of the base of the liquid container extends above the level of the end of the air inlet pipe terminating in the liquid container and there is provided liquid absorbing means which extends over a substantial area of the raised portion of the base and also extends below the intended level of liquid in the liquid container.

12. The apparatus as claimed in any one of claims 7 to 11 where in the reservoir is fitted with an airtight removable filter cap.

13. The apparatus as claimed in claim 12 wherein the liquid supply pipe is provided with a valve assembly arranged to prevent liquid from flowing from the reservoir when said filter cap is removed.

14. Apparatus for maintaining a desired level of liquid in a container by gravity flow substantially as herein before described with reference to figures 1 and 2 of the accompanying drawings.

1 5. Apparatus for maintaining a desired level of liquid in a container by gravity flow substantially as hereinbefore described with referencéto figures 3 and 4 of the accompanying drawings.