GB2352158A

GB2352158A - Ground sprinkler apparatus

Info

Publication number: GB2352158A
Application number: GB0012346A
Authority: GB
Inventors: Charles Michael Oxley; Andrew Nicholas Oxley
Original assignee: PZ Products Ltd
Current assignee: PZ Products Ltd
Priority date: 1999-07-20
Filing date: 2000-05-23
Publication date: 2001-01-24
Also published as: GB9916843D0; GB0012346D0

Abstract

A ground sprinkler apparatus 10 comprises a tank 12 having an outlet 28. The outlet 28 is connected to a sprinkler head 66. The sprinkler head 66 has a plurality of orifices 72. Liquid from the tank 12 is forced through the orifices 72 by gravity alone. The tank 12 is mounted on a frame 16 such that the outlet 28 and the orifices 72 are arranged so that as the level of the liquid changes, the change in the flow rate of the liquid through one of the orifices is the same as the change in the flow rate through the other orifices. The invention also relates to a method of treating the ground. The method comprises the steps of providing a ground sprinkler apparatus 10 having wheels 100 of a circumference of fixed length. A means for indicating a revolution of one or more of the wheels is provided. Furthermore, a pulse generating means is provided which emits a pulse at a set frequency. In use, the ground sprinkler apparatus 10 is moved at a speed such that the rate of revolution of the wheels 100 substantially matches the rate of pulse emission.

Description

2352158 P300066GB Ground Sprinkler Apparatus The invention relates to a

ground sprinkler apparatus. In particular, the invention is for use on, amongst other surfaces, grass, soil, tarmac and paved surfaces.

Hand held watering cans are used with sprinkler attachments to sprinkle the ground with water and other water-based solutions. Openings of a watering can sprinkler are sized to allow maximum flow rate out of the openings when the can is full of liquid. However, the flow rate steadily decreases to a trickle when the liquid in the can is at a low level.

This is emphasised further if a user adopts a sprinkling routine whereby he begins sprinkling in the same start position and ends sprinkling in the same end position every time.

Crop sprayers are used to treat crops with chemical solutions such as pesticides and fertilizers. These devices are normally operated by the user pumping the liquid from the sprayer as he sprays or by pressurizing the liquid reservoir in advance. Such a highly pressurised solution atomises when sprayed and forms a fine spray which is susceptible to drifting on the wind. The spray can drift onto areas which do not require, or cannot tolerate, treatment. Additionally, the spray may coat the clothes and body of the user. The unpredictability of the spray direction is a particular problem when using poisonous solutions. Moreover, it is 2 difficult to maintain and measure the rate of ground coverage of liquid with either of the above methods.

An object of the invention is to provide an improved ground sprinkler apparatus and a method of sprinkling or spraying the ground.

According to one aspect of the present invention there is provided a ground sprinkler apparatus comprising a liquid supply having an outlet, the outlet being connected to a sprinkler head, the sprinkler head having a plurality of orifices, liquid from the liquid supply being forced through the orifices by gravity alone, the liquid supply being mounted on a frame, wherein the orifices are arranged to be choked substantially regardless of the level of liquid in the liquid supply.

In that way, the flow rate through the sprinkler head is constant over a broad range of liquid levels in the liquid supply.

Preferably, the orifices are equally sized and equally spaced across the sprinkler head. In that way, the liquid is applied over the ground at a substantially unifon-n rate across the head, i.e. a similar amount of liquid through each of the orifices.

3 According to another aspect of the invention there is provided a ground sprinkler apparatus comprising a liquid supply having an outlet, the outlet being connected to a sprinkler head, the sprinkler head having a plurality of orifices, liquid from the supply being forced through the orifices by gravity alone, the liquid supply being mounted on a frame such that the outlet and the orifices are arranged so that as the level of the liquid supply changes, the change in the flow rate of the liquid through one of the orifices is the same as the change in the flow rate through the other orifices.

The liquid supply may be a tank supported by the frame, the frame being mounted on wheels.

Preferably, the sprinkler head is arranged to treat the ground between the wheels. In that way, the ground sprinkler apparatus can cover an area without overlap and waste.

Preferably, the wheels have a circumference of known length and there is provided means for indicating a revolution of one or more of the wheels.

4 In that way, the distance travelled by the ground sprinkler apparatus is measurable and the area covered by the ground sprinkler apparatus can be calculated.

Preferably, where a bottom surface of the tank is flat, the outlet of the tank is in the said bottom surface. In that way, liquid can flow through the outlet until the tank is almost empty.

Preferably, the outlet is an aperture fitted with a valve. The valve is preferably actuated by operating a cable. Preferably, the cable actuates a valve stop. The cable itself may be lever-actuated or, preferably, constructed so as to form a curve of cable that is pulled to actuate the valve stop. Preferably, pulling the cable opens the valve stop. In that way, the passage of liquid can be controlled and liquid can be retained whilst the apparatus is transported.

Preferably, the sprinkler means is removable. In that way, it can be easily cleaned and replaced if necessary.

The lever or curve of cable is preferably mounted within easy reach of a handlebar of the frame. In that way the user can control the direction of the apparatus and easily operate the lever or cable itself to control fluid dispersal.

In another embodiment of the invention, a pulse generating means is provided which emits a pulse at a set frequency. The ground sprinkler apparatus can be moved at a speed so that the rate of revolution of the wheels matches the rate of pulse emission. The set frequency can be any one of a range of frequencies, all of which correspond to known application rates. The user can also use the pulses as an aid to maintaining a constant pace, for example by synchronising walking strides with the pulses. Preferably, a chart would show the desired walking speed for the desired application rate. The user would Preferably achieve this speed through a trial and error process, timing the coverage of a measured distance, adjusting the pulse frequency as necessary.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which; Fig. I is a schematic side view of a ground sprinkler apparatus in accordance with the invention, Fig. 2a is a cross section of a valve of the ground sprinkler apparatus of Fig.

Fig. 2b is a plan view of the valve of Fig. 2a, 6 Fig. 3 is a perspective view of a second ground sprinkler apparatus in accordance with the invention, Fig. 4 is an exploded perspective view of a valve of the second ground sprinkler apparatus of Fig. 3, Fig. 5 is a perspective view of a sprinkler head of the ground sprinkler apparatus of Fig. 3, Fig. 6 is a perspective view of a third ground sprinkler apparatus in accordance with the invention, Fig. 7 is an exploded perspective view of a valve of the third ground sprinkler apparatus of Fig. 6, Fig. 8 is a perspective view of a sprinkler head of the third ground sprinkler apparatus.

Referring to Fig. 1, a ground sprinkler apparatus 10 comprises a tank 12 for a liquid 14, the tank being supported, when assembled, by a frame 16.

7 The tank 12 has an opening 18 in a top surface 20 to allow filling of the tank 12 and a closure lid 22 that prevents contaminants entering the liquid 14 and the liquid from spilling out.

A bottom surface 24 of the tank 12 has a further lid 25, through which the tank is connected to a valve body 26. Referring to Fig. 2, an end 27 of the valve body 26 adjacent the further lid 25 defines an outlet 28 of the tank 12 through which liquid 14 can flow when a valve 30 is opened. The opposite end 31 of the valve body 26 is connected to a pipe 32.

The tank 12 has sufficient capacity, eg 25L, to treat a large area and its size allows portability.

The frame 16 comprises a stem 33, a first support 34 and a second support 36.

The stem 33 comprises a first stem part 38 and a second stem part 40 that are assembled together in a known way. The first stem part 3 8 has a handlebar 42. The stem 33 is of a length which provides the user with the handlebar 42 at a convenient height.

8 The first support 34 comprises a length of material 44 which is U-shaped in plan and which comprises legs 46 and a bight portion 48.

The legs 46 of the U-shaped length of material 44 are bent through approximately 90 degrees at knees 50, so as to extend towards the ground. The legs 46 have rubber stops 52 in their ends 54. In that way, the ends 54 do not cut into soft surfaces and do not scrape against hard surfaces.

The second support 36 comprises an inverted U-shape frame which is attached near its free ends 57 to the length of material 44 of the first support 34 by means of bolts 56.

The assembled stem 33 is connected to the first support 34 by bolts 58 and connected to the second support 36 by bolts 60. The stem 33 and the supports 34, 36 when interconnected provide a solid frame 16.

The tank 12 is supported by the legs 46 and bight portion 48 of the first support 34. The second support 36 prevents sideways movement of the tank 12.

A band 62 attached to the second support 36 is arranged to surround the tank 12 and is tightened so as to secure the tank 12 to the second support 36, thereby 9 minimising fore-and-aft and lateral movement thereof The band 62 has a clip 64 that allows adjustment of the band 62 and may allow a different size tank to be retained.

A sprinkler head 66 is connected to the pipe 32. The sprinkler head 66 comprises an inverted T-shaped pipe, having a down pipe part 68 and an elongate sprinkler tube part 70 arranged at one end of, and transverse to, the down pipe part 68. The sprinkler tube part 70 has a plurality of equally-sized orifices 72 formed in a lower part 74 and arranged in a row along the length thereof. The orifices 72 are located at an angle a from the central axis, A of the down pipe part 68, as illustrated in Fig. 1.

The sprinkler head 66 is removable for ease of cleaning.

The geometry of the orifices 72 and the outlet 28 controls the flow rate of liquid 14 from the ground sprinkler apparatus 10. The orifices 72 are arranged to be choked substantially regardless of the level of liquid in the liquid supply in order to give a constant flow rate of liquid 14 through the orifices from when the tank 12 is full to when the tank is nearly empty. When the liquid supply is a tank 12 having a capacity of 25 Litres, the flow rate of the liquid is constant whilst the tank 12 has between 25 litres and 5 litres in it. The flow rate subsequently reduces at a slow rate.

Liquid 14 flows out of all of the orifices 72 until the tank is empty or almost empty.

The orifices 72 are spaced apart to provide a substantially uniform application of the liquid 14 to the ground 76 (or any other suitable surface) and the spaces between the orifices are small so that there is substantially complete coverage of the ground 76 under the ground sprinkler apparatus 10.

In Fig. 2a, the valve 30 is shown fitted in the outlet 28. The valve body 26 has a locking collar 80 at the end 27. A small distance along the valve body 26 is an outer transverse wall 8 1. The valve housing 83 has a lower lip in the form of an L-section annulus 84 and openings 85 for liquid 14. The valve housing 83 further comprises a first recess 86 on its outer surface and a second recess 87 on its inner surface. A central bore 88 joins the two recesses 86, 87. The locking collar 80 is pushed through the further lid 25 and a sealing ring 82 is positioned between the wall 81 and the further lid 25, The locking collar 80 clips onto the L-section annulus to retain the valve housing 83. The valve 30 has a valve stop 89 that covers the end 27 of the valve body 26 to close the outlet 28. A compression spring 90 sits on the valve stop 89 and locates in the second recess 87. In its non-nal state the valve 30 is closed.

I I A first end 91 of an inner control cable 92 is connected to the valve stop 89 and passes through the spring 90 and the bore 88. As seen in Figs. I and 2, the inner control cable 92 is arranged inside a fixed outer tube 93 in a "Bowden" arrangement. A first end 94 of the outer tube 93 abuts the first recess 86. The inner control cable 92 is a nylon monofilament and the outer tube 93, is a nylon pipe. As shown in Fig. 1. the cable 92 and the tube 93 pass through the tank 12. A notch 95 provided in the closure lid 22 allows the cable 92 and tube 93 to leave the tank 12.

Referring to Fig. 1, a lever housing 96 is mounted on the handlebar 42. A second end 97 of the inner control cable 92 is attached to a lever (not shown) and a second end 98 of the fixed outer tube 93 abuts the lever housing 94. Depressing the lever pulls the inner control cable 92 relative to the fixed outer tube 93 and the inner control cable 92 activates the valve stop 89 against the bias of the spring 90 to open the valve 30. When the lever is released the spring 90 forces the valve stop 89 back to close the valve 30.

Wheels 100 are mounted on the second stem part 40 or on an axle member attached thereto to make the frame 16 easily moveable. The sprinkler head 66 is arranged so that it treats only the ground 76 between the wheels 100.

12 The distance between the wheels 100 is easily divisible into the standard unit of a metre, for example half a metre. The wheels 100 have a narrow profile so that they mark the ground 76 and the wheels 100 tracks formed signify to the user that an area of ground 76 has been covered. The wheels 100 have a known perimeter that is easily divisible into a metre, for example one metre. The perimeter of one or each of wheels 100 is provided with means for indicating a rotation or part of a rotation (not shown) thereof The means for indicating a rotation comprises a clicker arranged on the wheels 100. An additional clicker can signify part rotations. It may also be a visual marker on a part of the wheel.

A pulse generating means 101 (not shown) is provided and is mounted on the handlebar 42, or it may be a separate apparatus, for example, worn on the belt of the user.

In use, the tank 12 is filled with liquid such as a chemical solution 14. The solution in the tank 12 has only gravity acting on it and remains at atmospheric pressure.

When the lever is depressed, the valve 30 opens to allow solution 14 to flow through the outlet 28. The solution 14 flows down the pipe 32, through the down pipe part 68 and into each half of the sprinkler tube part 70 in approximately equal 13 arnounts. The solution 14 flows out of the orifices 72 at the lower part 74 along axis B. Due to the outlet arrangement, all of the solution 14 leaves the tank 12.

A setting on the pulse generating means 10 1 is selected and a pulse is emitted which corresponds to a known rate of solution application to the ground 76. The user pushes the ground sprinkler apparatus 10 so that the rate of rotation of the wheels 100 matches the rate of pulse emission of pulse generating means 101. In that way, a particular area of ground 76 is covered in a particular time and the ground 76 is constantly sprinkled.

For example, one setting on the pulse generating means 10 1 emits 4 pulses in 2 seconds.

Since the rate of rotation of the wheels 100 matches the rate of pulse emission there must be 4 clicks in 2 seconds.

Since n + I clicks correspond to n rotations of the wheels 100 and the wheel perimeter is one metre then the user and the ground sprinkler apparatus 10 travel 3 metres every 2 seconds or 1 1/2 metres per second. The distance between the wheels 100 is 1/2 metre so the apparatus covers 0.75 square metres per second. If the flow rate of solution 14 through the orifices 72 is set at 0.5 litres per second then 14 2/3 litre per unit area are applied. Hence, 4.5 litres of solution 14 are applied over 6.75 square metres (approx. 7 square metres).

In a first mode of controlling the application of the solution 14, a multi-position switch 102 is set at different positions, corresponding to a quicker or slower rate, and the ground sprinkler apparatus 10 is pushed quicker or slower accordingly so that the rate of rotation of wheels 100 matches the rate of pulse emission. In that way, a greater or lesser area of ground 76 is covered. Consequentl),, the ground receives a lesser or greater coverage of solution 14, respectively. For example, another setting may disperse 4.5 litres of solution 14 over 10 square metres - In a second mode of controlling the application of the solution 14, a potentiometer 104 is adjusted so that at a particular setting, the number of pulses per unit amount of solution 14 applied matches a known rate of solution 14 application.

In a third mode of controlling the application of the solution 14, one of wheels 100 has a magnet 106 attached on its perimeter which passes a reed switch 108 attached to the second stem part 40 on each rotation.

The pulse generating means 101 has a switch 110 with settings "run", "off' and "calibrate".

A potentiometer 104 is adjusted as in the second mode. With the switch set at "run" the user watches the means for indicating wheel speed (not shown) which indicates whether the ground sprinkler apparatus 10 is moving too fast, at the correct speed, or too slow. A set of lights could do the same.

With the switch set at "calibrate", the potentiometer 104 emits a pulse at a particular rate. The rate is adjusted so that at a particular application rate (setting 1, setting 2, etc) the number of pulses per unit amount of solution 14 applied matches a known rate of solution 14 application.

A further ground sprinkler apparatus 120 in accordance with the invention is shown in Fig. 3, where all parts in Fig. 3 correspond with all parts in Fig. I respectively, except, referring to Fig. 3, the ground sprinkler apparatus 120 has a first support 122 comprising two substantially parallel tubes 124 that the tank 12 sits on. A second support 126 has feet 128 attached to it that allow the ground sprinkler apparatus 120 to stand. The second support 126 has an integral loop 130 that the tank 12 is held within.

A first stem part 132 comprises a handlebar 134 and parallel struts 136. A second stem part 138 comprises further struts 140 that engage struts 136.

16 A sprinkler head 142 has orifices 144 located in a lowest part 146 of a sprinkler tube part 148.

A down pipe part 149 is inclined forwards from the vertical axis C along axis D so that it aligns with the pipe 32 and the valve body 156 (see Fig. 4).

Looking at Fig. 4, a valve 150 comprises a valve part 152 having a seal 154 and a valve body 156 having a shoulder 158, the seal 154 abutting the shoulder 158 to close the valve 150. The shoulder 158 defines an outlet 159 that is normally closed. A tension spring 160 is connected between a ring 162 on the valve part 152 and an internal cross-piece (not shown) on the valve body 156. The valve body 156 is inclined at the region 163 of the cross-piece. The valve part 152 is tied to one end of a nylon monofilament 164, the other end of the monofilament being connected to a lever 166 mounted on a handlebar 134, as shown in Fig. 3.

A first end 168 of a fixed outer cable 170 abuts the top surface 20 of the tank 12 and a second end 172 abuts a holder 174 attached to one of the parallel struts 13 6.

17 In use, pulling or depressing the lever 166 pulls the valve part 152 away from the shoulder 158 to open the valve 150. The natural bias of the spring 160 closes the valve 150 when the lever 166 is released.

A further ground sprinkler apparatus 180 in accordance with the invention is shown in Fig. 6. Parts in Fig. 6 corresponding with parts in Fig. 3 carry the same reference numerals. Referring to Fig. 6, the ground sprinkler apparatus 180 has a U-shaped first support 182 in place of the two tubes 124 of the ground sprinkler apparatus 120 of Fig. 3. The parallel struts 136 of the handle are secured to the further struts 140 and to the first support 182 by means of nuts and bolts, the bolts extending through holes in the struts 136, 140 and supports 182. The ends of the bolts have thumbwheels 183 to enable easy tightening/loosening thereof. The handle can pivot when the bolts are loosened so that the struts 136 can be folded relative to the further struts 140 into a stored position for compact storage.

The U-shaped support 182 has a central hole 184 (not shown in detail) inboard of the support. In place of the arrangement of Fig. 3, the second support 126 is pivotably connected near ends 185 to the U-shaped support 182. A V-shaped foot 186 is pivotably attached at ends 187 to the second stem part 138. In use, the ends 185 of the second support 126 and the ends 187 of the V-shaped foot 186 (only 18 one set of ends shown for clarity) are telescopically engaged and preferably locked to form a solid stand. The V-shaped foot 186 provides stability on soft ground.

A notch 188 is provided in the upper surface 20 of the tank 12 adjacent the opening 18 (as in Fig. 1) that allows a monofilament 164 to leave the tank 12. It also serves as an entry point for part of the tank closure lid 22.

Whereas a "Bowden" arrangement is used in Fig. 3, in Fig. 6 a single monofilament 164 is used. Also, in place of the lever 166 and holder 174 arrangement of Fig. 3, the monofilament 164 is attached (shown at 192) near the handlebar 134 to one of the struts 136 and threaded through a ring 190 opposite to the attachment on the other strut 136. The length of monofilament 164 between the attachment 192 and the ring 190 is loosely covered with a plastics tube 194.

The sprinkler head 128 has four elongate sprinkler tube parts 200 arranged, two on each side, of the down pipe part 68.

Each of the sprinkler tube parts 200 are detachable. In that way, the total coverage and alignment of the sprinkler head 198 is variable.

19 A cap 201 (see Fig. 8) is arranged on one end of each sprinkler tube part 200 to close the end of the said respective part 200. In that way, the length of tube can be selected and the tube parts 200 arranged together and the ends of the two end most tube parts can be closed off using he respective caps 201.

Referring to Fig. 7, a valve 202 for the ground sprinkler apparatus 180 of Fig. 6 is similar to that shown in Fig. 4 Referring to Fig. 7, the valve 202 comprises a valve part 204 having an O-ring 206. A valve housing 208 comprises an L-section annulus 210 having struts 212 extending from its upper surface 214 the struts being diametrically opposed to each other. The struts 212 are joined by an upper strut 216 which has a disc 217 formed centrally therein.

The disc 217 has a bore 218. The bore 218 is co-axial with the L-section annulus 210, the valve part 204 and the valve body 156. The valve body 156 is arranged within the valve housing 208. The shoulder 158 of the body abuts against the upper surface 214 of the housing.

The valve part 204 has a through-bore 220 to receive the monofilament 164. The monofilament 164 passes through the through-bore 220 in the valve part 204 and a securing member 222 is crimped to the end of the monofilament 164. The valve part 204 sits on the valve body 156, the O-ring 206 sealing against the shoulder 158 to close the outlet 159.

A compression spring 224 is arranged on the valve part 204, the monofilament 164 passing through the spring and the bore 218 in the disc 217. In use, the part of the monofilarnent 164 between the attachment 192 and the ring 190 is pulled causing the valve part to move away from the shoulder against the action of the spring 224 which is compressed against the disc 216. The O-ring 206 moves away from the shoulder 158 to open the valve 202, thereby letting liquid 14 through the outlet 159.

The valve body 156 has a ramp 226 and a projecting pin 228. When the tank 12 is lowered into the frame 16 the ramp 226 compresses the flexible tank 12 against the first support 182 allowing the pin 228 to engage in the aforementioned central hole 184 when the ramp 226 passes beyond the centre line of the first support 182. The engagement of the pin 228 in the hole 184 helps the tank 12 to counter- resist the valve operating force. The pin 228 also keeps the valve body 156 central between the sides of the support 182 and stops the tank 12 from rotating. A flange 230 on the valve body 156 is kept substantially in contact with the U- shaped support 192, thus preventing rotational movement of the valve body 156 and therefore ensuring that the sprinkler head 142 does not move in use.

21 When the ground sprinkler apparatus 180 is not in use there are several options for storage. The tank 12 may be left in place and the thumbwheels 183 slackened to allow the struts 136 to fold around the further struts 140. Alternatively, the tank 12 may be removed, the connection between the second support 126 and the V-shaped base 186 released and the frame 16 suspended on a wall from the handlebar 134. If preferred, the frame 16 may be completely collapsed.

In the apparatus 120 of Figs. I to 4 the frame 16 may be manufactured differently but in that way the parts can be flat-packed in a box after manufacture and easily assembled by the user. The frame 16 may have an extension that allows for storage of a second tank (not shown).

The tank 12 could be of a different geometry that allows improved control of the apparatus 10 and minimises the risk of toppling. The closure lid 22 of the tank 12 may have a locking mechanism (not shown) so that the closure lid 22 remains on the tank 12 if the tank leans, or falls over.

The tank 12 may incorporate parts of the frame 16 such as the foot 186 and/or the second stem part 138.

22 Alternatively, a single part (not shown) may replace foot 186, second stem part 138, the axle tube and the second support 126 which incorporates integral loop 130. The single part is preferably moulded from plastics material. The single part may have the first stem part 132 attached directly to it, and can rest with the tank 12.

The tank 12 could be replaced by any other liquid supply means, for example, a hose pipe linked to a mains water supply.

The pipe 32 is rigid but a flexible tube (not shown) may be provided where it is desirable to move the sprinkler head 66 to various vertical and horizontal positions. It may also be desirable to assemble the sprinkler head 66 to one side of the apparatus. In that way, the wheels can remain on a surface such as a lawn and the sprinkler head 66 can treat the edge of the lawn.

Moreover, the sprinkler tube part 70, 148 may be rotatable so that the orifices 72, 144 are adjustable from sprinkling forward- facing to sprinkling backward- facing. Such an arrangement enables the ground sprinkler apparatus 10, 120 to counter wind forces or to aid the user in seeing the area to which the liquid 14 is applied. The orifices 72, 144 may be of different size to each other if required, the spaces between the orifices 72, 144 may be different and the orifices 72, 144 may be removed and replaced with an elongate opening or a series of elongate openings in the lower part 74 or lowest part 146 of the sprinkler tube part 70, 148.

2 3 The valve body 26 may have a filter (not shown) over it to prevent debris from blocking the orifices 72.

Additionally, wheels (not shown) can be positioned on the legs 46 near ends 54 or on the second support 126 so that the apparatus 10, 120 need not be lifted.

The pulse generating means 101 may have volume, pitch and frequency control.

Claims

24 Claims

1. A ground sprinkler apparatus comprising a liquid supply having an outlet, the outlet being connected to a sprinkler head, the sprink-ler head having a plurality of orifices, liquid from the liquid supply being forced through the orifices by gravity alone, the liquid supply being mounted on a frame, wherein the orifices are arranged to be choked substantially regardless of the level of liquid in the liquid supply.

2. A ground sprinkler apparatus comprising a liquid supply having an outlet, the outlet being connected to a sprinkler head, the sprinkler head having a plurality of orifices, liquid from the supply being forced through the orifices by gravity alone, the liquid supply being mounted on a frame such that the outlet and the orifices are arranged so that as the level of the liquid supply changes, the change in the flow rate of the liquid through one of the orifices is the same as the change in the flow rate through the other orifices.

3. A ground sprinkler apparatus according to any preceding claim, wherein the orifices are equally sized and equally spaced across the sprinkler head.

4. A ground sprinkler apparatus according to any preceding claim, wherein the liquid supply is a tank supported by the frame, the frame being mounted on wheels.

5. A ground sprinkler apparatus according to claim 4, wherein the sprinkler head is arranged to treat the ground between the wheels.

6. A ground sprinkler apparatus according to claim 4 or 5, wherein the wheels have a circumference of known length and there is provided means for indicating a revolution of one or more of the wheels.

7. A ground sprinkler apparatus according to any preceding claim wherein a bottom surface of the tank is flat and the outlet of the tank is in the bottom surface.

8. A ground sprinkler apparatus according to any preceding claim, wherein the outlet is an aperture fitted with a valve.

9. A ground sprinkler apparatus according to claim 8, wherein the valve is actuated by operating a cable.

10. A ground sprinkler apparatus according to claim 9, wherein the cable actuates a valve stop.

11. A ground sprinkler apparatus according to claim 9 or 10, wherein cable itself is]ever-actuated.

12. A ground sprinkler apparatus according to claim 10 ' wherein the cable is constructed so as to form a curve of cable that is pulled to actuate the valve stop.

13. A ground sprinkler apparatus according to any of claims 10 or 11, wherein pulling the cables opens the valve stop, the valve stop being normally biased closed.

14. A ground sprinkler apparatus according to any preceding claim, wherein the sprinkler head is removable.

15. A ground sprinkler apparatus according to claim I I or 12, wherein the lever or curve of cable is mounted within easy reach of a handlebar of the frame.

16. A ground sprinkler apparatus according to any preceding claim, wherein a pulse generating means is provided which emits a pulse at a set frequency.

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17. A ground sprinkler apparatus according to claim 16, wherein a chart would show the desired walking speed for the desired application rate.

18. A ground sprinkler apparatus substantially as described herein and with reference to the drawings.

19. A method of treating the ground comprising the steps of providing a ground sprinkler apparatus in accordance with claim 6, 18 or any of claims 7 to 17 when dependent upon claim 6, comprising providing a pulse generating means which emits a pulse at a set frequency, and moving the ground sprinkler apparatus at a speed such that the rate of revolution of the wheels substantially matches the rate of pulse emission.

20. A method as claimed in claim 19, comprising the step of positioning the pulse generating means separately on the user.

21. A method as claimed in any of claims 19-20, comprising selecting a setting on the pulse rate generating means such that a pulse is selected which corresponds to a known rate of solution application to the ground.

22. A method as claimed in any of claims 19-21, and comprising providing a multi-position switch, the positions of the switch corresponding to different pulse rates, selecting a position corresponding to a desired pulse rate and pushing the ground sprinkle apparatus accordingly so that the rate of rotation of the wheels matches the rate of the pulse selected.

27

23. A method as claimed in any of the claims 19-22, wherein the step of providing means for indicating rate of revolution of wheels comprises providing a reed switch or a magnet on a fixed part of the ground sprinkler apparatus, and providing the other on a wheel of the ground sprinkler apparatus.

24. A method as claimed in claim 23, comprising providing on one of the wheels a magnet which passes a reed switch attached to the fixed part of the ground sprinkler apparatus on each rotation.

25. A method as claimed in claim 23 or 24, comprising providing a magnet on or adjacent the perimeter of one of the wheels.

26. A method as claimed in any of claims 19-25, and comprising providing a potentiometer having a plurality of settings corresponding to difference pulse rates, selecting a setting corresponding to a desired pulse rate, and pushing the ground sprinkler apparatus accordingly so that the rate of rotation of the wheels matches the rate of the pulse selected.

27. A method as claimed in claim 26 wherein the step of providing a plurality of settings comprises providing "run", "off'and "calibrate" settings.

28. A method as claimed in claim 27, comprising providing a potentiometer having a plurality of settings corresponding to different pulse rates, adjusting the potentiometer, selecting "run", moving the apparatus across the ground and monitoring a means for indicating wheel speed to assess if the ground sprinkler apparatus is moving too fast, at the correct speed or too slow.

29. A method as claimed in claim 28, wherein the step of providing means for indicating wheel speed comprises providing a set of lights which are arranged to indicate if the rate of travel is too fast or too slow.

28

30. A method as claimed in claim 29, wherein the step of providing a set of lights comprises providing three lights, one indicating rate of travel is too fast, one indicating rate of travel is too slow and one indicating rate of travel is correct.

31. A method as claimed in any of claims 27 to 30, comprising providing a potentiometer having a plurality of settings corresponding to different pulse rates, selecting "calibrate" to automatically adjust the pulse rate so that the number of pulses per unit amount of solution applied match a predetermined rate of solution application.