GB2067271A - Watering apparatus - Google Patents

Abstract

An apparatus for intermittently turning on a water supply at intervals determined by a property of the environment comprises a water tank (10), a float-operated valve (46) connected between a water supply pipe (12) and a water delivery pipe (16), means sensitive to the property of the environment to remove water from the tank, for example a piece of towelling partially immersed in the water which removes the water by capillary action and evaporation at a rate determined by ambient humidity, and means (23) for diverting a part of the flow from the delivery pipe to replenish the tank. The apparatus further includes a first ball catch (25) adapted to retain the valve in a fully off position for a finite time in opposition to the increasing effective weight of the float means (19', 19'') as the water level in the tank falls during water removal, and a second ball catch (26) adapted to retain the valve in a substantially fully on position for a finite time in opposition to the increasing buoyancy force exerted on the float means as the water level in the tank rises during water replenishment. The strength of the catches (25, 26) is related to the weight and buoyancy of the float means in such manner as to provide a rapid movement of the valve to the fully on and off positions. <IMAGE>

Description

SPECIFICATION Watering apparatus This invention relates to watering apparatus, in particular to apparatus for intermittently turning on a water supply at intervals determined by a property of the environment. The invention involves the use of a float means which is coupled to a stop cock, gate valve or like device for turning a water supply on and off by vertical movement of the float means, any arrangement of such kind being hereinafter referred to as a ballcock.

The invention is concerned with the problem of watering gardens, greenhouses or the like, or alternatively providing drinking water for animals, without undue waste of water, and without the need for supervision or attendance during, for example, weekends, holidays and other wanted or unwanted interruptions of routine.

The invention therefore provides an apparatus for intermittently turning on a water supply at intervals determined by a property of the environment, the apparatus comprising a water tank, a ballcock mounted in the tank, a water supply pipe connected to the ballcock inlet, a water delivery pipe connected to the ballcock outlet, means sensitive to the property of the environment to remove water from the tank, means for diverting a part of the flow from the delivery pipe to replenish the tank, and yieldable catch means adapted to retain the ballcock in a fully off position for a finite time in opposition to the increasing effective weight of the ballcock float means as the water level in the tank falls during water removal and adapted to retain the ballcock in a substantially fully on position for a finite time in opposition to the increasing buoyancy force exerted on the float means as the water level in the tank rises during water replenishment, the strength of the catch means being related to the weight and buoyancy of the float means in such manner as to provide a rapid movement of the ballcock to the fully on position when the catch means yields to the weight of the float means as the water level falls and to the fully off position when the catch means yields to the buoyancy force of the float means as the water level rises, thereby providing the said retention of the ballcock alternatively in the fully on and fully off positions.

The advantage of the invention is that despite the gradual change in the water level in the tank during both removal and replenishment of the water, finite periods of watering are provided with the water supplied at substantially the full pressure of the supply throughout each such period, the water being fully cut off between such periods with no gradual reduction or increase in the water supply rate between the two states.

Preferably, the ballcock is of a kind comprising a float support arm pivotted at one end for movement in a vertical plane and adapted for engagement with the said catch means at the other end, and at least one float carried below the arm, movement of the said arm being effective to turn the water supply on and off. In such case it is advantageous that the said at least one float is carried below the arm by a lost motion connection permitting a limited degree of vertical movement of the float relative to the arm.

The catch means may comprise separate upper and lower catches adapted to arrest the ballcock in the fully off and fully on positions respectively.

Preferably in this case, each catch comprises a respective ball catch wherein the ball is biased by a spring, and means are provided to adjust the compression of the spring.

It is preferred that the means sensitive to a property of the environment comprises a capillary body partially immersed in the water and partially exposed to the atmosphere for removing water from the tank at a rate dependent upon the humidity of the atmosphere. For example, the capillary body may be a piece of textile material such as towelling.

In the above arrangement, the tank may comprise slow drainage means operative independently of the property of the environment whereby a minimum frequency of watering operations is guaranteed.

The invention will be understood in greater detail from the following description of embodiments thereof given by way of example only with reference to the accompanying drawings in which: Fig. 1 is a side sectional view of a first embodiment of the invention, Fig. 2 is a plan view of the embodiment of Fig. 1 with its stops omitted for clarity, Fig. 3 is a perspective view of a second embodiment of the invention, Fig. 4 is a plan view of the embodiment of Fig. 3, and Fig. 5 is a side cross-section of the embodiment of Fig. 3 when the tank is empty.

Referring to Figs. 1 and 2 of the drawings, there is illustrated a first embodiment of watering apparatus according to the invention which comprises a water tank indicated at 10 and a generally conventional type of ballcock 11 mounted in the tank 10. The ballcock 11 comprises a gate valve 1 3 having an inlet 14 connected to a water supply pipe 12 such as a mains supply or header tank, and having an outlet 1 5 connected to a water delivery pipe 16, the latter being connected to garden or greenhouse watering devices (not shown) or to an animal trough, for example. A float support arm 1 7 of the ballcock 11 is pivotally mounted at one end 1 8 on the gate valve 13 for movement in a vertical plane to operate the gate valve.A ball float 1 9 is rigidly connected to the underside of arm 1 7 by means of a rod 20, the latter being threaded at its armengaging end 21 and secured to the arm by nuts 22. The valve 13 is further provided at its outlet 1 5 with a nipple 23 of substantially lesser diameter than the delivery pipe 16, whereby a small part of the flow from the delivery pipe 16 is diverted so as to replenish the water in the tank 10 as hereinafter described.

A pair of adjustable threshold catches provided on wall 24 of the tank 10 comprises an upper ball catch 25 and a lower ball catch 26 which, in use, retain the ballcock 11 in its fully off and fully on positions respectively. The arm 17 is provided at its free end 27 with a recess 36 which is adapted to receive each of balls 28, 29 of the bail catches 25, 26 respectively. Each of the balls 28, 29 is biased by a spring (not shown) and screws 30, 31 are provided to adjust the compression of the springs. A pair of plastic stops 32, 33 are also mounted on the wall 24, embracing the catches 25 and 26 and serving to limit the vertical movement of the arm 17.

A piece of towelling (not shown) is folded over the top of one of walls 34, 35 of the tank 10 so that it reaches the bottom of the interior of said tank 10.

In use, with the recess 36 in the end 37 of the arm 17 engaged by the upper ball catch 25 (Fig. 1) the valve 13 is closed and the water supply is fully off. The water level in the tank 10 gradually falls through capillary action of the piece of towelling and subsequent evaporation, but the upper catch 25 retains the ballcock in the fully off position for a finite time in opposition to the gradually increasing effective weight of the float 19. However, when the water falls to a level at which the downward force exerted by the ballcock exceeds the threshold oi the catch 25 as determined by the force of the spring in the catch, the arm 17 suddenly disengages from the ball catch 25 and moves rapidly downwards to meet the lower stop 23 and engage the lower ball catch 26, as shown in dotted outline in Fig. 1.

Simultaneously the valve 13 opens, the water supply is turned fully on and water is delivered to a desired locus, for example a garden.

A portion of the water supply replenishes the tank 10 through the nipple 23, but the engagement of the end 37 of arm 17 with the lower ball catch 26 retains the ballcock in the fully on position for a finite time in opposition to the increasing buoyancy force exerted by the float 19 as the water level in the tank 10 gradually rises.

However, when the water rises to a level at which the upward force exerted by the ballcock exceeds the threshold of the lower catch 26 as determined by the force of the spring in the ball catch 26, the arm 17 suddenly disengages from the catch 26 and moves rapidly upwards to meet stop 32 and engage the upper catch 25, thus fully closing the valve 13 whereby the water supply is shut off. The ballcock has now returned to the position shown in solid lines in Fig. 1, and the above sequence of events occurs intermittently at intervals dependent upon the rate of evaporation from the towelling, the period for which water is delivered in each case being determined by the time for which the lower catch 26 holds the arm 17 in its lower position.

It will be appreciated from the above that the weight and buoyancy of the float 1 9 are chosen in relation to the strength of the catches 25 and 26 in such manner as to provide a rapid movement of the arm 17 between the fully on and fully off positions of the ballcock and vice versa, to ensure not only that the water supply is rapidly shut off or turned on as the case may be, but also to ensure that in both directions of movement of the arm 17 the ballcock has sufficient kinetic energy to overcome the resistance of the ball catch towards which it is moving so that the arm can become properly latched against the return movement.

Considering this requirement in relation to the above embodiment, since conventional ballcocks are usually constructed of lightweight materials the upper catch 25 must be set to a relatively low spring bias to permit release of the arm 17 at least by the time the water level has fallen to the bottom of the float. Upon such release, the upward buoyancy on float 19 rapidly increases as the float falls and so becomes more submerged in the water, leading to a rapid deceleration of the arm 1 7. This means that lower catch 26 must be positioned closely below upper catch 25 to ensure that the arm 1 7 reaches the lower catch 26, and catch 26 must also be of relatively low spring bias to ensure proper latching of the arm 1 7. This means that only a small rise in water level will cause the arm 17 to snap back up to the off position.

Thus switching between the upper and lower positions will occur for only small changes in the water level in the tank, so that the watering periods will be frequent but of short duration.

While this may be suitable for some applications, a disadvantage is that the relatively light loading on the ball catches means that their thresholds are subject to change as a result of dirt, temperature changes, etc. so that reliable operation cannot be ensured without regular cleaning and maintenance.

A second embodiment of the invention will therefore now be described with reference to Figs.

3 to 5, which is designed to provide watering at less frequent intervals but for a longer period each time, and also to enable the catches to be-set at a stronger bias to reduce the effects of dirt and temperature. In Figs. 3 to 5, components which perform a similar function to components in Figs.

1 and 2 have been given the same reference numerals.

In the embodiment of Figs. 3 to 5, the tank 10 is mounted in an open frame 40 which also carries upper and lower ball catches 25 and 26 respectively in vertically fixed positions on a post 41. As before, the ballcock comprises an arm 17, the latter being pivotted at one end 18 to the frame 40 for movement in a vertical plane. The arm 1 7 carries a roller 42 at its opposite free end, the roller 42 being mounted between a pair of extension plates 43 secured to opposite sides ot the free end of the arm. The position of the roller 42 in relation to the balls 28 and 29 of the catches 25, 26 respectively is such that the arm can only pass each catch by depression of the corresponding ball against the force of its associated compression spring.

The ballcock further comprises a stop cock 46 also mounted on the frame 40 and connected between the water supply pipe 12 and the water delivery pipe 16, the stop cock 46 being operatively coupled by linkages 44, 45 to the arm 1 7. The arrangement is such that for any position of the free end of the arm 1 7 above the upper ball catch 25 the water supply is fully off, whereas for any position of the free end of the arm 17 below the lower ball catch 26 the water supply is fully on. A manually operable stop cock 23', corresponding to the nipple 23 of Figs. 1 and 2, diverts a small part of the water flow from the delivery pipe 1 6 to the tank 10.

Finally, the ballcock comprises a pair of floats 19' and 19", taking the place of the single float 1 9 of the first embodiment. The floats 19' and 19" are of similar volume and generally cubic in shape; however the float 19' nearer the free end of the arm 1 7 is weighted at 50 whereas the other float 19" is unweighted. Furthermore, the unweighted float 19" is secured at a fixed position below the arm 17 on a rod 20", whereas the weighted float 19' is coupled to the arm 17 by a lost motion connection permitting a limited degree of vertical movement of the float i 9' relative to the arm.This lost motion connection is achieved by permitting the supporting rod 20' of the float 19' to slide in an aperture in the arm 1 7, the limits of the lost motion being defined by upper and lower stops 48 and 49 respectively carried by the rod 20'.

The above apparatus operates as follows.

Starting from the fully on position shown in Fig. 5, the water level gradually rises in the tank 10 by replenishment through the stop cock 23'. The floats 19' and 19" also rise up with the water, and hence the arm 17, but the latter is retained for a finite time in the fully on position of the stop cock 46 by abutment of the roller 42 against the underside of the ball 29. However, when the combined buoyancy force exerted by the two floats (the float 19' acting via the lower stop 49) exceeds the threshold of the lower catch 26, the arm 1 7 moves rapidly upwardly with sufficient kinetic energy to push past the upper ball catch 25 so that the ballcock assumes the fully off position with the roller 1 7 above the ball 28 of the upper catch 25.

As the water level now falls by capillary action and evaporation (the apparatus also includes a piece of towelling draped over the edge of the tank as in the first embodiment), the floats and thus the arm 17 fall. However, the arm 17 is retained for a finite time in the fully off position of the stop cock 46 by abutment of the roller 42 against the topside of the ball 28. Only when the combined weight of the floats 1 9' (now acting via the upper stop 48) and 1 9", together with the weight of the arm 17 and rods 20' and 20", exceed the threshold of the upper catch 25 is the arm released, the arm thereupon moving rapidly downwards with sufficient force to push past the lower ball catch 26 so that the ballcock assumes the fully on position with the roller 42 below the ball 29 of the lower catch 26.

The advantage of this second embodiment is that the weighted float 19' permits a stronger setting on the upper catch 25 to be used and, when released, provides sufficient inertia to overcome the resistance of the lower catch on the downward motion. A stronger setting may therefore also be used for the lower catch 26, the second unweighted float 19" being provided to supply sufficient buoyancy for the return motion.

The lost motion connection of the weighted float 19' to the arm 1 7 furthermore permits the water level to rise and fall further before the catches are overcome than if the float 1 9' were fixed - this provides watering operations at less frequent intervals but for a longer period each time.

Naturally, the watering periods and the intervals between them may be adjusted as desired by adjusting the weighting of the float 19', the degree of lost motion connection, and the strength of the catches.

In the foregoing embodiments, spring loaded ball catches were used for temporarily retaining the arm 17 in the fully on and fully off positions. It is to be understood that other kinds of catches may be used for this purpose, for example magnetic catches.

Claims (9)

1. An apparatus for intermittently turning on a water supply at intervals determined by a property of the environment, the apparatus comprising a water tank, a ballcock mounted in the tank, a water supply pipe connected to the ballcock inlet, a water delivery pipe connected to the ballcock outlet, means sensitive to the property of the environment to remove water from the tank, means for diverting a part of the flow from the delivery pipe to replenish the tank, and yieldable catch means adapted to retain the ballcock in a fully off position for a finite time in opposition to the increasing effective weight of the ballcock float means as the water level in the tank falls during water removal and adapted to retain the ballcock in a substantially fully on position for a finite time in opposition to the increasing buoyancy force exerted on the float means as the water level. in the tank rises during water replenishment, the strength of the catch means being related to the weight and buoyancy of the float means in such manner as to provide a rapid movement of the ballcock to the fully on position when the catch means yields to the weight of the float means as the water level falls and to the fully off position when the catch means yields to the buoyancy force of the float means as the water level rises, thereby providing the said retention of the ballcock alternatively in the fully on and fully off positions.

2. An apparatus according to claim 1, wherein the ballcock comprises a float support arm pivotted at one end for movement in a vertical plane and adapted for engagement with the said catch means at the other end, and at least one float carried below the arm, movement of the said arm being effective to turn the water supply on and off.

3. An apparatus according to claim 2, wherein the said at least one float is carried below the arm by a lost motion connection permitting a limited degree of vertical movement of the float relative to the arm.

4. An apparatus according to claim 3, wherein the said at least one float is weighted, and the ballcock further comprises a second float which is unweighted and is carried below the arm in a fixed position.

5. An apparatus according to claim 1, 2, 3 or 4, wherein the yieldable catch means comprises first and second threshold catches, the first threshold catch being adapted to hold the ballcock in the fully off position until the downward force exerted by the ballcock exceeds the threshold of the first catch as the water level falls, and the second threshold catch being adapted to hold the ballcock in the substantially fully on position until the upward force exerted by the ballcock exceeds the threshold of the second catch as the water level rises.

6. An apparatus according to claim 5, wherein the first and second catches comprise respective ball catches of which each ball is biased by a respective spring.

7. An apparatus according to claim 6, further comprising means to adjust the force exerted on each ball by its respective spring to thereby adjust the threshold of the corresponding catch.

8. An apparatus according to any preceding claim, wherein the means sensitive to a property of the environment comprises a capillary body partially immersed in the water in the tank and partially exposed to the atmosphere for removing water from the tank at a rate dependent upon the humidity of the atmosphere.

9. An apparatus as claimed in claim 1, substantially as described with reference to Figs. 1 and 2 orto Figs. 3 to 5 of the accompanying drawings.