WO2002018059A1

WO2002018059A1 - Fluid delivery system

Info

Publication number: WO2002018059A1
Application number: PCT/AU2001/001076
Authority: WO
Inventors: Leslie George Crane
Original assignee: CRANE VALMA ANN
Current assignee: CRANE VALMA ANN
Priority date: 2000-08-28
Filing date: 2001-08-28
Publication date: 2002-03-07
Anticipated expiration: 2003-02-28
Also published as: AUPQ974300A0

Abstract

A fluid delivery system particularly suitable for a boom spray apparatus having a boom (11) formed in a plurality of sections (13, 15). Each boom section (13, 15) has an entry end (19a) communicating with a common supply line (27) and a discharge end (19b) communicating with a common return path (50). Each boom section (13, 15) has spray nozzles (21) between the entry and the discharge end thereof. A valve system (29) is provided for controlling liquid flow along each boom section (13, 15) from the entry end (19a) to the discharge end (19b), with a one-way valve (55) being provided for preventing liquid flow along the boom section (13, 15) in the reverse direction from the discharge end (19b) to the entry end (19a). The return path (50) terminates at a discharge zone into which liquid flowing from the return line (50) can be discharged.

Description

Title

"Fluid Delivery System"

Field of the Invention

This invention relates to a fluid delivery system.

The invention has been devised particularly, although not solely, for use as a fluid delivery system in relation to an agricultural boom spray.

Background Art

An agricultural boom spray comprises a boom formed in sections each of which incorporates a multitude of spray nozzles for spraying a treatment liquid onto the ground over which the boom spray traverses.

The boom spray incorporates a fluid reticulation system for delivering the treatment liquid from a supply tank to the boom sections. The reticulation system includes a common supply line and a multitude of dedicated delivery lines each extending from the common supply line to a respective one of the boom sections for delivery of treatment liquid thereto. Each delivery line incorporates a solenoid control valve for selectively controlling flow of the treatment liquid along the delivery line from the common supply line to the respective boom section. The common supply line incorporates a pump and a filtering system.

A recirculation line is associated with the common supply line so that treatment liquid delivered from the supply tank by the pump can be recirculated and returned to the supply tank in circumstances where the solenoid control valves are closed. The recirculation is employed to agitate the treatment liquid contained within the supply tank to ensure that it remains properly mixed.

A rinse tank is provided for delivering a flushing liquid such as water to the supply line and to the boom sections so that the reticulation system can be flushed at the completion of the spraying operation. The rinse tank communicates with the supply line via a valve which can be selectively operated to allow a flushing liquid contained in the rinse tank to enter the supply line for ultimate delivery to the boom sections.

Each boom section has a valve fitted to its non-supply end. When a particular boom section is to be flushed, the valve at the non-supply end thereof is opened, as is the respective solenoid control valve, so as to allow flushing liquid to be delivered from the rinse tank along the supply line and respective delivery line to the boom section. In this way, the flushing liquid flows along the delivery line and through the boom section until the flushing operation is completed. The various boom sections can be sequentially flushed in this fashion, so displacing the remnants of the treatment liquid previously contained within the delivery line and boom section. Similarly, when the boom spray is being prepared for operation, the treatment liquid can be delivered along each delivery line and the respective boom section to displace the remnants of any flushing liquid contained therein and thereby charge them with treatment liquid.

A particular disadvantage of such an arrangement is that the treatment liquid and the flushing liquid are both discharged into the environment in an uncontrolled manner during the flushing and charging operations. A further disadvantage is that each of the valves at the non-supply end of each manifold section must be opened to enable the flushing and charging operations to be performed and then subsequently closed before the spraying operation can be performed.

It would be advantageous for there to be an arrangement where the flushing and treatment liquids are not discharged into the environment during the flushing and charging operations.

It is against this background, and the problems and difficulties associated therewith, that the present invention has been developed. Disclosure of the Invention

The present invention provides a fluid delivery system comprising a plurality of flow paths each having an entry end communicating with a common supply line and a discharge end communicating with a common discharge line, a valve means for controlling fluid flow along each flow path from the entry end to the discharge end, means for preventing fluid flow along the flow path in the reverse direction from the discharge end to the entry end, the discharge line terminating at a discharge zone into which fluid flowing along the discharge line can be discharged.

The fluid may be a gaseous fluid, a liquid, a slurry or any combination thereof.

Preferably, the fluid delivery system may further comprise a first reservoir from which the common supply line can receive a first fluid and a second reservoir from which the common supply line can receive a second fluid, and a control means operable to selectively control delivery of the first fluid on the second fluid to the common supply line.

The control means may comprise a valve having a first mode of operation allowing a flow of the first fluid along the common supply line while blocking flow of the second fluid, a second mode of operation allowing a flow of the second fluid along the common supply line while blocking flow of the first fluid, and a third mode of operation blocking flow of both the first and second fluids.

The discharge zone may comprise a reservoir which receives the discharging fluid flowing along the discharge line. The reservoir receiving the discharging fluid may comprise the first reservoir from which fluid is supplied to the common supply line or alternatively it may comprise a separate reservoir.

A branch line may be associated with the delivery line, the branch line incorporating a pressure indicator means for providing an indication of fluid pressure within the delivery line. The pressure indicator means may comprise a pressure gauge. The branch line may have an extension section which extends to the return line, with a valve for controlling fluid flow along the extension section.

The branch line may also incorporate a bleed means whereby fluid pressure in the branch line can progressively bleed therefrom. This may be achieved by providing a bleed line between the branch line and the discharge line, with a bleed valve incorporated in the bleed line.

The invention also provides a boom spray comprising a boom formed in a plurality of sections, each section having an entry end communicating with a common supply line and a discharge end communicating with a common return line, each boom section having at least one spray outlet between the entry and discharge ends thereof, a valve means for controlling liquid flow along each boom section from the entry end to the discharge end, means for preventing liquid flow along the boom section in the reverse direction from the discharge end to the entry end, the return line terminating at a discharge zone into which liquid flowing from the return line can be discharged.

Preferably, the boom spray further comprises a first reservoir from which the common supply line can receive a treatment liquid and a second reservoir from which the common supply line can receive a flushing liquid, and a control means operable to selectively control delivery of the treatment liquid or the flushing liquid to the common supply line.

The discharge zone may comprise a reservoir. The reservoir may comprise a reservoir from which treatment liquid is supplied to the boom. Alternatively, the reservoir may comprise a separate tank.

The common supply line may communicate with a plurality of delivery lines each extending from the common supply line to a respective one of the boom sections for delivery of liquid thereto. Preferably, each delivery line has a valve means associated therewith for selectively controlling flow of liquid along the delivery line from the common supply line to the respective boom section.

The common supply line may incorporate a pump and a filtering system.

Brief Description of the Drawings

The invention will be better understood by reference to the following description of several specific embodiment thereof as shown in the accompanying drawings which:

Figure 1 is a schematic view of the reticulation circuit of an agricultural boom spray according to a first embodiment; and

Figure 2 is a schematic view of the reticulation circuit of an agricultural boom spray according to a second embodiment.

Best Mode(s) for Carrying out the Invention

The embodiment shown in Figure 1 of the drawings is directed to the reticulation circuit 10 for a boom spray comprising a boom 11 carried on a mobile frame structure (not shown). The boom spray is adapted to spray a treatment liquid onto the ground over which it traverses. The boom 11 in this embodiment is in three sections comprising an inner section 13 and two outer sections 15. Typically, the outer sections 15 are movable between an extended condition (as shown in the drawings) and a folded condition (not shown) in known manner. Each boom section 13, 15 comprises a pipe section 19 and spray outlets such as nozzles 21 disposed along the pipe section. The treatment liquid is sprayed through the spray nozzles 21 and onto ground traversed by the spray boom.

The treatment liquid to be sprayed by the spray boom is contained in a reservoir 23 in the form of a main tank carried on the mobile frame structure. The treatment liquid is delivered to the boom sections 13, 15 by way of a reticulation system 25 which incorporates a common supply line 27, one end of which opens into the tank 23. The other end of the common supply line 27 communicates with a valve system 29 from which three delivery lines 31 extend. Each delivery line 31 communicates with a respective one of the boom sections 13, 15. Specifically, each delivery line 13 is connected to one end 19a of the respective pipe section 19 for delivery of treating fluid thereto. The valve system 29 incorporates a solenoid-controlled valve associated with each delivery line 31 for selectively controlling flow therealong from the common supply line 27.

The common supply line 27 incorporates a pump 35, a filter 37 on the suction side of pump 35 and a further filter 39 on the delivery side of pump 35.

A rinse tank 41 is connected to the supply line 27 through a three-way valve 43. The rinse tank 41 is adapted to contain a flushing liquid such as water for flushing the reticulation system 25 to remove remnants of the treatment liquid after a spraying operation has been performed. The three-way valve 43 controls delivery of the flushing liquid to the supply line. In a first mode of operation, the three-way valve 43 blocks flow of the flushing liquid into the delivery line 27 and allows treatment liquid to be pumped along the supply line 27 from the main tank 23. In a second mode of operation, the three-way valve 43 blocks flow of treatment liquid from the main tank 23 and allows flushing liquid to be pumped from the rinse tank 41. In a third mode of operation, the three-way valve 43 blocks liquid flow from both the main tank 23 and the rinse tank 41.

A recirculation line 28 extends between the end of the supply line 27 at the valve system 29 and the main tank 23 to permit treatment liquid to be recirculated thereby to ensure that the treatment liquid remains properly mixed. The extent to which the treatment liquid is recirculated can be controlled by a regulating valve 49 incorporated in the recirculation line 28.

The arrangement described so far is a typical layout for a conventional boom spray. With this known arrangement, when it is desired to flush the reticulation system 25 to remove remnants of treatment liquid after a spraying operation, flushing liquid is drawn from the rinse tank 41 and pumped through the various components. The flushing liquid is discharged to the surrounding environment through the spray nozzles 21 and through valves which are provided on the ends 19b of the boom sections 13, 15 opposite to the liquid delivery ends 19a thereof. The valves are opened to permit the flushing liquid to discharge through the ends 19b. The valves are then closed at the completion of the flushing operation. When a spraying operation is to be next performed, the valves are again opened and treatment liquid is pumped through the reticulation system to displace the remnants of any flushing liquid remaining therein, prior to commencement of the spraying operation. The valves are then closed so that the spraying operation can be performed.

In this embodiment treatment liquid and flushing liquid is not discharged to the surrounding environment through the ends 19b of the boom sections 13, 15 but rather is contained and returned to the reservoir 23. This is achieved by way of a liquid return system 50 which is substituted for the valves at the end 19b of the boom sections.

The liquid return system 50 comprises a return manifold 51 to which the discharge end 19b of each boom section 13, 15 is connected by way of a respective connection line 53. A one-way valve 55 is provided at the discharge end 19b of each boom section 13, 15 to ensure that liquid can flow from the boom section to the return manifold 51 but not in the reverse direction. The return manifold 51 communicates with the main tank 23 by way of a return line 57. A return valve 59 is incorporated in the return line 57.

With this arrangement, when the return valve 59 is closed so as to block flow along the return line 57, the boom spray operates in a normal manner in which treatment liquid pumped from the main tank 23 to the delivery lines 31 flow to the boom sections 13, 15 and discharges through the nozzles 21 to be sprayed onto the ground over which the boom spray is traversing. The treatment liquid does not flow beyond the boom sections 13, 15 and into the return system 50 because the return line 57 is blocked against fluid flow by the closed return valve 59. When the return valve 59 is open to permit fluid flow along the return line 57, any liquid pumped to the boom sections 13, 15 and 17 can flow into the return system 50. The liquid flows into the return system 50 rather than discharging through the spray nozzles 21 because of its tendency for the flow to follow the path of least resistance.

The return system 50 allows flushing liquid being pumped through the reticulation system 25 to be contained and delivered to the main tank 23 rather than being discharged to the surrounding environment during a flushing operation. Similarly, at a subsequent stage when the reticulation system 25 is being charged with treatment liquid from the tank 23 to discharge any remnants of flushing liquid remaining therein, the treatment liquid, as well as the remnants of flushing fluid, is returned to the main tank 23 rather than being discharged into the surrounding environment. Once the charging operation has been completed, the return valve 59 can be closed so as to block flow along the return line 57 and thereby ensure that treatment liquid delivered to the boom sections 13, 15 from the main tank 23 is discharged through the spray nozzles 21 in the boom sections rather than passing along the return system to the tank 23.

Typically, each boom section 13, 15 and its associated delivery line 31 would be flushed separately of the other boom sections. This can be achieved by way of the valve system 29 which can selectively control delivery of flushing liquid along each delivery line 31 to the respective boom section. Typically, the boom sections 31 , 15 and associated delivery lines 31 would be flushed one after another.

The non-return valves 55 at the discharge ends 19b of the boom sections 13, 15 prevent reverse flow of liquid along the boom sections.

The return system 50 incorporates a branch line 61 communicating with the return line 57 at location 62 along the length of the return line 57. The branch line 61 incorporates a pressure indicating means 65 in the form of a pressure gauge. The purpose of the branch lines 61 and the pressure gauge 65 incorporated therein is to provide a visual indication to an operator of the boom spray that there is fluid pressure within the return system 50, thereby confirming that treatment liquid is being pumped from the main tank 23 to the boom sections 13, 15. Any disruption to the delivery of treatment liquid to the boom sections 13, 15 would result in a pressure reduction in the return line 57 which would then be reflected by a reduction in the reading given by the pressure gauge 65. A bleed line 67 extends between the branch line 61 and the return line 57 and has a bleed valve 69 incorporated therein. The purpose of the bleed line 67 and bleed valve 69 is to ensure that there is a pressure reduction in the branch line 61 in circumstances where there is a blockage or some other form of restriction to delivery of treatment liquid to the boom sections. In the event of such a blockage, it may be that there would not necessarily be a reduction in fluid pressure in the branch line 61 if fluid pressure were not bled therefrom, in which case, a false indication could be provided by the pressure gauge 65. The pressure bleed avoids the potential for such a problem.

The branch line 61 also incorporates an extension section 70 which extends to the return line 57 and communicates therewith at location 63. The branch line 61 also incorporates a flushing valve 71 which, when opened, permits flushing fluid to flow along the branch line 61 for flushing purposes during the flushing operation. Normally, the flushing valve 71 is closed.

In this embodiment, flushing liquid in the reticulation system 25 is returned to the main tank 23 when it is being purged from the reticulation system. It is believed that allowing the flushing liquid to discharge into the main tank 23 will not adversely dilute the treatment liquid contained therein because of the very limited quantities of flushing liquid involved. However, if there are circumstances where it is desired not to discharge the flushing liquid into the main tank 23 where it can dilute the treatment liquid, a separate reservoir for receiving the purged flushing liquid can be provided. One such arrangement is utilised in the second embodiment shown in Figure 2. The second embodiment is similar to the first embodiment and so like reference numerals are used to identify like parts. The second embodiment incorporates a receiving tank 81 to receive the flushing liquid instead of the latter being discharged into the main tank 23. From the foregoing, it is evident that the present invention provides a simple, yet highly effective, system for flushing the reticulation system 25 of a boom spray, and purging flushing liquid from the reticulation system, without the liquid discharging to the surrounding environment as is the case with existing arrangements.

It should be appreciated that the scope of the invention is not limited to the scope of the embodiments described. In particular, it should be appreciated that there may be various applications for a fluid delivery system according to the embodiment in fields other than boom sprays.

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Claims

The Claims Defining the Invention are as Follows

1. A fluid delivery system comprising a plurality of flow paths each having an entry end communicating with a common supply line and a discharge end communicating with a common discharge line, a valve means for controlling fluid flow along each flow path from the entry end to the discharge end, means for preventing fluid flow along the flow path in the reverse direction from the discharge end to the entry end, the discharge line terminating at a discharge zone into which fluid flowing along the discharge line can be discharged.

2. A fluid delivery system according to claim 1 further comprising a first reservoir from which the common supply line can receive a first fluid and a second reservoir from which the common supply line can receive a second fluid, and a control means operable to selectively control delivery of the first fluid on the second fluid to the common supply line.

3. A fluid delivery system according to claim 2, wherein the control means comprises a control valve.

4. A fluid delivery system according to claim 1 , 2 or 3, wherein the discharge zone comprises a discharge reservoir for receiving the discharging fluid flowing along the discharge line.

5. A fluid delivery system according to claim 4, wherein the discharge reservoir comprises the first reservoir and/or the second reservoir.

6. A fluid delivery system according to any one of the preceding claims, wherein a branch line is associated with the delivery line, the branch line incorporating pressure indicator means for providing an indication of fluid pressure within the delivery line.

7. A fluid delivery system according to claim 6, wherein the branch line has an extension section extending to the return line, with a valve for controlling fluid flow along the extension section.

8. A fluid delivery system according to claim 6 or 7, wherein the branch line incorporates a bleed means whereby fluid pressure in the branch line can progressively bleed therefrom.

9. A fluid delivery system according to claim 8, wherein a bleed line is provided between the branch line and the discharge line, with a bleed valve incorporated in the bleed line.

10. A boom spray comprising a boom formed in a plurality of sections, each section having an entry end communicating with a common supply line and a discharge end communicating with a common return line, each boom section having at least one spray outlet between the entry and the discharge end thereof, a valve means for controlling liquid flow along each boom section from the entry end to the discharge end, means for preventing liquid flow along the boom section in the reverse direction from the discharge end to the entry end, the return line terminating at a discharge zone into which liquid flowing from the return line can be discharged.

11. A boom spray according to claim 10 further comprising a first reservoir from which the common supply line can receive a treatment liquid and a second reservoir from which the common supply line can receive a flushing liquid, and a control means operable to selectively control delivery of the treatment liquid or the flushing liquid to the common supply line.

12. A fluid delivery system according to claim 11 wherein the control means comprises a control valve.

13. A fluid delivery system according to claim 10, 11 or 12, wherein the discharge zone comprises a discharge reservoir for receiving the discharging liquid flowing along the discharge line.

14. A fluid delivery system according to claim 13, wherein the discharge reservoir comprises the first reservoir.

15. A boom spray according to any one of claims 10 to 14, wherein a branch line is associated with the delivery line, the branch line incorporating pressure indicator means for providing an indication of liquid pressure within the delivery line.

16. A boom spray according to claim 15, wherein the branch line has an extension section extending to the return line, with a valve for controlling liquid flow along the extension section.

17. A boom spray according to claim 15 or 16, wherein the branch line incorporates a bleed means whereby liquid pressure in the branch line can progressively bleed therefrom.

18. A boom spray according to claim 17, wherein a bleed line is provided between the branch line and the discharge line, with a bleed valve incorporated in the bleed line.

19. A boom spray according to any one of the claims 10 to 18, wherein the common supply line communicates with a plurality of delivery lines each extending from the common supply line to a respective one of the boom sections for delivery of liquid thereto.

20. A boom spray according to claim 19, wherein each delivery line has a valve means associated therewith for selectively controlling flow of liquid along the delivery line from the common supply line to the respective boom section.

21. A boom spray according to any one of claims 10 to 20, wherein the common supply line incorporates a pump and a filtering system.

22. A fluid delivery system substantially as herein described with reference to the accompanying drawings.

23. A boom spray substantially as herein described with reference to the accompanying drawings!