OA12497A - A device for dispensing liquids. - Google Patents

Abstract

A device for dispensing liquids such as herbicides to weeds includes a reservoir 10 for containing the herbicide. The reservoir is connected to a wiping head by a handle which has a pipe therein. The pipe is connected to the reservoir and to flow control mechanisms located in the wiping head. The flow control mechanisms ensure a relatively constant flow rate of the herbicide out of the wiping head when the herbicide is being dispensed.

Description

i 012497 -1- A Device for Dispensing Liquids

BACKGROOND OF THE INVENTION THIS invention relates to a device for dispensing liquids, particulariy to a tooifor applying liquids to plants or other materials such as weeds growing in afield.

Tools for wiping plants with Chemicals, particulariy herbicides are well known.5 These are distinct from devices which spray or dust the plants with chemicais.

However, the various tools for wiping'which are currently available hâve a largevariability in the rate of flow of the liquid being used to wipe the targetedunwanted plants. This arises from the nature of the mechanism which isusually an absorbent wick suppiied with herbicide from a réservoir incorporated Π0 intothetool.

The various mechanisms used for sealing the wicks to the réservoirs do notpermit précisé flow rates of liquids through the tool. Furthermore, as the levelof liquid falls during use, the head of liquid is progressively reduced whichfurther adds to the inconsistent flow rates. Ί 5 The présent invention séeks to address this by providing an improved devicefor dispensing liquids.

DUPLICATA Ο1249γ -2-

SUMMARY OF THE INVENTION

According to the présent invention there is provided a device for dispensingliquids, the device comprising: a réservoir for containing the liquid to be dispensed; a wiping head inciuding a porous material through whïch the liquid is5 able to pass to be dispensed; and at least one flow contrat mechanism located between the réservoir andthe porous material to control the fluid flow rate to the porous materialso that the fluid flows to the porous material at a substantially constantrate.

The device may further include a pipe connecting the réservoir to the wipinghead,

Preferably, the device includes a plurality of flow control mechanisms locatedin the wiping head.

The plurality of flow control mechanisms may be spaced apart in the wipingΊ 5 head to achieve a predetermined flow rate.

Preferably, the device includes a handle, wherein the réservoir is connected tothe top of the handle and the wiping head is connected to the bottom of thehandle.

DUPLICATA ο 12497 -3-

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a device for dispensing liquids according to the présentinvention;

Figure 2 is a cross-section through Figure 1 ; and

Figure 3 shows the wiping head of Figures 1 and 2 in an exploded form.

DESCRIPTION OF AN EMBODIMENT

Refemng to Figure 1, a device for dispensing liquids such as herbicidesincludes a réservoir 10 for containing the liquid to be dispensed.

The réservoir 10 is formed from a UV stabiiised plastic container such as avery hard polyethylene bottle. 5 The container has a screw threaded cap 12 which can be removed to allow the liquid to be piaced into the réservoir 10. tn one embodiment, an air valve (not shown) could also be incorporated intothe réservoir. However, in the prototype it was found that ioosening the cap 12slightfy had the required effect and the air valve was not needed. ΊΟ The réservoir 10 is connected to a handle 14*iormed from a PVC tube 32miüimeters in diameter and approximately 1.2 meters long.

The connection between the réservoir 10 and the handle 14 is effected using aconnector 16 which has a passage therethrough. This can be more clearly

DUPLICATA \Ί » 012497 -4- seen in Figure 2. The bottom of the handle 14 is connected to a T-piece 18.This piece can more ciearly be seen in Figure 3. A wiping head 20 is connected to the T-piece. Referring to Figure 3. the baseof the wiping head 20 is formed from a PVC tube 22 which is eut into a C- 5 section. Located in the C-section is a tube 24 with at ieast one flow controlmechanism in the form of a précision emitter 26.

It wili be appreciated that a plurai’rty of précision emitters 26 are typicaily used.Three embodiments of the prototype hâve been deveioped in this regard.Firstiy, a twenty centimeter long head includes two emitters 26. A forty ΊΟ centimeter head includes four emitters, and lastly, a sixty centimeter headincludes six emitters.

Applications requiring more emitters, such as mounting the device on atractor, could use more emitters which are spaced over a much broader area,for example, up to 12 meters in length.' 15 In general, the emitters are spaced ten centimeters apart. By varying thespacing between the emitters, the desired flow rate for the device can beachieved depending on the application for which the device is to be used. Theemitter is used in the prototype of the invention were so-called "drip-lineirrigation pipe" emitters which are typicaily used in irrigation applications. 2q Exampies of these emitters are manufactured by Netafim™.

In general, the flow rate dépends on the emitters used, the operating height ofthe head and the viscosity of the liquid being dispensed. The flow rate of theprototype of the présent invention, at an operating height of 1.1 métrés andusing a concentrated herbicidal mix, was between 0.42 to 0.44 iitres/hour per 25 emitter.

DUPLICATA 012497 -5-

As mentioned above, the emitters used in the prototype are the kind of emittersused in drip irrigation Systems but other kinds of flow control mechanismscould also be employed, such as pumps delivering a constant pressure.

The emitters are connected to the réservoir 10 by a pipe 28 and a T-piece 30. 5 Liquid in the réservoir 10 will flow down the pipe 28 and via the T-piece 30 tothe emitters 26.

In the iliustrated embodiment, the emitters are formed in two pipes connectedtogether in the centre to the T-piece 30. The ends of these two pipes areciamped to prevent fluid from flowing out of the ends of the pipes, tt will be ΊΟ appreciated that the emitters could be formed in shorter sections of pipe whichare themseives joined together.

The emitters are encased in a first porous material typically a low density foam32. The first tayer of foam 32 includes holes 34 corresponding to the emitters26. η Another two layers of higher density foam 36 are placed over the first layer offoam and the combination is covered with a porous, hard wearing fabric sheath40. The sheath 40 is typically made from a hard wearing nylon fabric. it will be appreciated that the number of layers could be alîered.

In use, the réservoir 10 is filled with the liquid herbicide mixture, such asglyphosate. The device is then rapidly inverted to prevent the gravitationai flowof the liquid to the emitters 26.

To wipe weeds, the tool is positioned the right way up as shown in Figure 1and the liquid begins flowing through the emitters 26, into the surrounding

DUPLICATA 012497 -6- foam and finally into the encasing fabric. The tool is then wiped onto thegrowing weeds which the herbicide will act to kill.

The length of the handle allows the user to hold the wiping head behind themwhile they walk forward and wipe the weeds so as not to get the herbicide onthe users legs.

Thus, it wili be appreciated that due to the substantially constant flowcharacteristic, it is possible to apply a chosen amount of Chemical to a weedpopulation by selecting a speed of travel along the ground, either manually orby mounting the device on a machine.

DUPLICATA

Claims (3)

1. 012497 -7- Claitns

   1. A device for dispensing liquide, ihe device comprising: a wiping head including a porous matériel through which the liquid isable to pass to be dispensed; a réservoir for containing the liquid to be dispensed the réservoir beingspaced apart from the wiping and being connected to the wiping head 5 by a pipe; and a piuraiity of fiow controi mechanisms located between the réservoirand the porous material to controi the fluid fiow rate to the porousmatériel so that, in use, the fluid flows to the porous material at asubstantially constant rate. ΊΟ 2. A device according to claim 1 wherein the piuraiity of fiow controimechanisms are spaced apart in the wiping head to achieve a predeterminedfiow rate.
2. 3. A device according to any preceding claim further including a handle, whereinthe réservoir is connected to the top of the handle and the wiping head is Ί 5 connected to the bottom of the handle.
3. 4. A device substantially as hereïn described with référencé to theaccompanying drawings. DUPLICATA