Liquid distribution systems, crop sprayers, and related methods

Abstract

A liquid distribution system of a crop sprayer includes a product tank configured to contain a liquid, a pump in fluid communication with the product tank, at least one nozzle carried by a boom and configured to receive the liquid from the pump through a supply line, a recirculation line connecting the at least one nozzle to the product tank, and a manifold between the supply line and the recirculation line, the manifold comprising a flow control valve comprising one of a three-way valve or a four-way valve, the flow control valve in fluid communication with the supply line and a fluid line configured to receive the liquid from the flow control valve during a spraying operation or from the at least one nozzle during a recirculation operation. Related crop sprayers and methods are also disclosed.

Description

TITLELIQUID DISTRIBUTION SYSTEMS, CROP SPRAYERS, AND RELATED METHODSCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of the filing date of U.S. Provisional Patent Application 63 / 601,095, "Liquid Distribution Systems, Crop Sprayers, and Related Methods," filed November 20, 2023, the entire disclosure of which is incorporated herein by reference.FIELD

[0002] Embodiments of the present disclosure relate generally to plumbing for a boom arm on a crop sprayer, and more particularly to a liquid distribution system connecting a plurality of spray nozzles along the boom arm to a liquid supply line and including a recirculation line.BACKGROUND

[0003] High crop yields of modern agribusiness may require application of fertilizers, pesticides, fungicides, and / or herbicides. Dispersing these chemicals onto high-acreage fields requires specialized machines mounted on or towed by a vehicle. An example of such a machine is a self-propelled crop sprayer.

[0004] A common design for a self-propelled crop sprayer includes a chassis with a tank, boom arms, and nozzles connected to the boom arms. The tank contains liquid product, such as fertilizers, pesticides, fungicides, and / or herbicides. Boom arms extend outward from the sides of the chassis. Boom plumbing contains supply lines and nozzles spaced apart along the length of the boom arms at a spacing corresponding to the spray pattern of the nozzles. In operation, as the crop sprayer crosses the field, liquid is pumped from the tank through the supply lines along the boom arms, and out through the nozzles. This allows the self-propelled sprayer to distribute the liquid along a relatively wide path. The length of conventional boom arms may vary from, for example, 6 meters (18 feet) up to 46 meters (150 feet), but shorter or longer booms are possible. The boom arms typically swing in for on-road transport and out for field-spraying operations.

[0005] Conventionally, the nozzles are connected in series such that the product flows through a pipe and / or hose from one nozzle to another. Booms have been of the "wet boom" type, where the boom comprises a frame member with a pipe mounted thereon, and the liquid passes through the pipe into nozzles mounted on the pipe and liquidly connected thereto, or a "dry boom" type, where the nozzles are mounted to the frame member and liquid passes to the nozzles through a hose which is connected between the nozzles. The nozzles are attached to the pipe or frame with brackets at desired intervals along the boom arm.

[0006] When a sprayer is first used to dispense a particular product, the product may be flushed through the pipe or hose to each nozzle to fill the entire plumbing system with the product. This may help to remove air bubbles and ensure that any prior products are purged from the system. To avoid uneven distribution of the product, this flushing and purging process may be performed before the sprayer enters the planted area of the field. This process may dispense several gallons of product out of the boom to ensure that all of the air is out of the boom and that liquid product can consistently and evenly be dispensed from each of the nozzles.

[0007] Some methods of flushing or purging spray systems are disclosed in International Patent Publication WO 2022 / 243750 Al, "Liquid Distribution Systems for Crop Sprayers, and Related Methods," published November 24, 2022.BRIEF SUMMARY

[0008] According to an aspect of the disclosure, a liquid distribution system of a crop sprayer includes a product tank configured to contain a liquid, a pump in fluid communication with the product tank, at least one nozzle carried by a boom and configured to receive the liquid from the pump through a supply line, a recirculation line connecting the at least one nozzle to the product tank, and a flow control valve in fluid communication with the supply line and a fluid line configured to receive the liquid from the flow control valve, the flow control valve comprising one of a three-way valve or a four-way valve, a position of the flow control valve configured to change between a spraying operation and a recirculation operation. During the spraying operation, the fluid line is configured to receive liquid from the flow control valve and direct the liquid to the at least one nozzle, and during the recirculation operation, the fluidline is configured to receive liquid from the supply line proximate the at least one nozzle and direct the liquid to the recirculation line.

[0009] The flow control valve may be between the supply line and the at least one nozzle. The manifold may further include an additional valve configured to direct the liquid from the fluid line to the recirculation line or the at least one nozzle based on a position of the additional valve.

[0010] The additional valve may include a three-way valve in fluid communication with the flow control valve, the fluid line, and the recirculation line. In some embodiments, the additional valve is located at an intersection between the fluid line and the recirculation line. In some embodiments, the additional valve is located in a flow path between the flow control valve and the at least one nozzle.

[0011] In some embodiments, the additional valve is in fluid communication with the flow control valve, the liquid distribution system further comprising a recirculation valve within the recirculation line proximate the intersection between the fluid line and the recirculation line.

[0012] The at least one nozzle may be in a flow path between the supply line and the recirculation line.

[0013] The flow control valve may include a three-way valve. In addition, the three- way valve may include two open ports and a third port having a smaller orifice than the two open ports. In some embodiments, the three-way valve is configured to induce a larger pressure drop between the supply line and the fluid line than between the supply line and the at least one nozzle.

[0014] In some embodiments, the flow control valve comprises a four-way valve.

[0015] The fluid line is in a flow path between the flow control valve and the at least one nozzle. In some embodiments, the fluid line is in a flow path between the flow control valve and the recirculation line.

[0016] The liquid distribution system may further include an air supply line between the product tank and the flow control valve, the air supply line configured to receivepressurized air to return liquid within the supply line, the at least one nozzle, and the recirculation line to the product tank.

[0017] In some embodiments, the liquid distribution system further includes an air supply line in the recirculation line and configured to purge the recirculation line of liquid.

[0018] In some embodiments, a crop sprayer comprises the liquid distribution system. The crop sprayer includes wheels, a chassis supported by the wheels, and an engine configured to propel the crop sprayer. In other embodiments, the crop sprayer comprises a track.

[0019] In some embodiments, a method of operating a crop sprayer comprising a product tank, a pump, a supply line, a boom carrying at least one nozzle configured to receive liquid from the supply line, a recirculation line connecting the at least one nozzle to the product tank, a flow control valve in fluid communication with the supply line, and a fluid line between the at least one nozzle and the recirculation line includes pumping liquid from the product tank through the supply line to the flow control valve, from the flow control valve to the fluid line, and from each of the supply line and the fluid line to the at least one nozzle, changing a position of the flow control valve, and pumping additional liquid through the flow control valve and to the at least one nozzle, and from the at least one nozzle through the fluid line to the recirculation line.

[0020] Changing a position of the flow control valve may include changing a position of a three-way valve or a four-way valve.

[0021] The method may further include changing a position of a second valve when pumping the additional liquid from the at least one nozzle through the fluid line to the recirculation line to recirculate the additional liquid.

[0022] In some embodiments, the method further includes purging the supply line with compressed air to return the liquid in the supply line to the product tank.BRIEF DESCRIPTION OF THE DRAWINGS

[0023] While the specification concludes with claims particularly pointing out and distinctly claiming what are regarded as embodiments of the present disclosure, various features and advantages may be more readily ascertained from the following description of example embodiments when read in conjunction with the accompanying drawings, in which:

[0024] FIG. 1 illustrates an agricultural vehicle in the form of a self-propelled crop sprayer;

[0025] FIG. 2 illustrates a portion of a spray boom of the crop sprayer shown in FIG. 1;

[0026] FIG. 3 is a simplified top view of another agricultural vehicle, in the form of a crop sprayer towed by a tractor; and

[0027] FIG. 4A through FIG. 4C are simplified schematics of an application system in respective spraying, recirculation, and purge configurations that may be used in the agricultural vehicle of FIG. 1 or FIG. 3;

[0028] FIG. 5 is a simplified cross-section of a three-way valve that may be used in the application system of FIG. 4A and FIG. 4B;

[0029] FIG. 6A and FIG. 6B are simplified schematics of an application system in a respective spraying configuration and a recirculation configuration that may be used in the agricultural vehicle of FIG. 1 or FIG. 3;

[0030] FIG. 7A through FIG. 7C are simplified schematics of an application system in respective spraying, recirculation, and purge configurations that may be used in the agricultural vehicle of FIG. 1 or FIG. 3;

[0031] FIG. 8A and FIG. 8B are simplified schematics of an application system in a respective spraying configuration and a recirculation configuration that may be used in the agricultural vehicle of FIG. 1 or FIG. 3; and

[0032] FIG. 9 is a simplified flow chart illustrating a method of operating a crop sprayer.DETAILED DESCRIPTION

[0033] The illustrations presented herein are not actual views of any crop sprayer or portion thereof, but are merely idealized representations to describe example embodiments of the present disclosure. Additionally, elements common between figures may retain the same numerical designation.

[0034] The following description provides specific details of embodiments. However, a person of ordinary skill in the art will understand that the embodiments of the disclosure may be practiced without employing many such specific details. Indeed, the embodiments of thedisclosure may be practiced in conjunction with conventional techniques employed in the industry. In addition, the description provided below does not include all elements to form a complete structure or assembly. Only those process acts and structures necessary to understand the embodiments of the disclosure are described in detail below. Additional conventional acts and structures may be used. The drawings accompanying the application are for illustrative purposes only, and are thus not drawn to scale.

[0035] As used herein, a position of a valve refers to turning, opening, and / or closing a valve and not to a physical location of the valve within a flow line. The position of the valve may affect the flow (e.g., direction, rate) through the valve. As only one example, changing a position of a valve may include changing the position of the valve from the open position to the closed position.

[0036] As used herein, the terms "comprising," "including," "containing," "characterized by," and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps, but also include the more restrictive terms "consisting of" and "consisting essentially of" and grammatical equivalents thereof.

[0037] As used herein, the term "may" with respect to a material, structure, feature, or method act indicates that such is contemplated for use in implementation of an embodiment of the disclosure, and such term is used in preference to the more restrictive term "is" so as to avoid any implication that other, compatible materials, structures, features, and methods usable in combination therewith should or must be excluded.

[0038] As used herein, the term "configured" refers to a size, shape, material composition, and arrangement of one or more of at least one structure and at least one apparatus facilitating operation of one or more of the structure and the apparatus in a predetermined way.

[0039] As used herein, the singular forms following "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0040] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0041] As used herein, the term "substantially" in reference to a given parameter, property, or condition means and includes to a degree that one of ordinary skill in the art would understand that the given parameter, property, or condition is met with a degree of variance, such as within acceptable manufacturing tolerances. By way of example, depending on the particular parameter, property, or condition that is substantially met, the parameter, property, or condition may be at least 90.0% met, at least 95.0% met, at least 99.0% met, or even at least 99.9% met.

[0042] As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range.

[0043] FIG. 1 shows a crop sprayer 102 used to deliver chemicals to agricultural crops in a field. The crop sprayer 102 includes a chassis 104 supported by wheels 109 or a track. The crop sprayer 102 may include an operator cab 106 mounted on the chassis 104. The operator cab 106 may house controls for the crop sprayer 102. An engine 108 may be mounted on a forward portion of chassis 104 in front of the operator cab 106 or may be mounted on a rearward portion of the chassis 104 behind the operator cab 106. The engine 108 may be commercially available from a variety of sources and may include, for example, a diesel engine or a gasoline-powered internal combustion engine, a battery-powered electric motor, etc. The engine 108 provides energy to propel the crop sprayer 102 through a field on wheels 109 or tracks, and may also provide energy to spray liquids from the crop sprayer 102.

[0044] The crop sprayer 102 further includes a product tank 110 to store a liquid to be sprayed on the field. The liquid may include chemicals, such as but not limited to, herbicides, pesticides, fungicides, and / or fertilizers. The product tank 110 may be mounted on the chassis 104, either in front of or behind the operator cab 106. The crop sprayer 102 may include more than one product tank 110 to store different chemicals to be sprayed on the field. The stored chemicals may be dispersed by the crop sprayer 102 one at a time, or different chemicals may be mixed and dispersed together in a variety of mixtures.

[0045] A boom 112 on the crop sprayer 102 is used to distribute the liquid from the product tank 110 over a wide swath as the crop sprayer 102 is driven through the field. Theboom 112 may include two or more portions that can fold for transport on public roadways, and unfold (i.e., to the position shown in FIG. 1) for field operations. FIG. 2 is a simplified perspective view of a portion a boom arm 202 of the boom 112. Liquid is conveyed from the product tank 110 (FIG. 1) by a liquid distribution system 204 to various spray nozzle 206 spaced along the boom 112. The liquid distribution system 204, which may be mounted on the boom arm 202, includes at least one supply line and a recirculation line connected to the product tank 110 (FIG. 1). The spray nozzles 206 may be substantially similar to the spray nozzles described in U.S. Patent Application 2022 / 0264865, "Hydraulic Spray Nozzle," published August 25, 2022, or in International Patent Publication WO 2021 / 067739 A2, "Parameter Sensing for a Liquid Applicator," published April 8, 2021.

[0046] FIG. 3 shows another crop sprayer 302 that may be used to deliver chemicals to agricultural crops in a field. The crop sprayer 302 is a pull-type sprayer including a chassis 304 carrying product tank 110. The crop sprayer 302 has a hitch 306 configured to couple the chassis 304 to a tractor 308. The tractor 308 may therefore pull the crop sprayer 302 through the field, and the operator of the tractor 308 may also operate the crop sprayer 302 via a control system in the cab of the tractor 308. The boom arms 202 may fold for road transport (indicated by dashed lines in FIG. 3). The crop sprayer 302 includes a liquid distribution system 204, as in FIG. 2 and described in further detail below.

[0047] FIG. 4A is a simplified schematic illustrating how the liquid distribution system 204 may be configured during a spraying operation. FIG. 4B is a simplified schematic illustrating how the liquid distribution system 204 may be configured during a recirculation operation. In FIG. 4A and FIG. 4B, arrows have been used for convenience to illustrate a direction of liquid flow through the liquid distribution system 204 during the respective spraying and recirculation operations.

[0048] A pump 402 in fluid communication with the product tank 110 pumps liquid from the product tank 110 through a supply line 404 to the spray nozzles 206, which are mounted along the boom arm 202 (FIG. 2) at a preselected interval. Each spray nozzle 206 may dispense the liquid onto crops as the crop sprayer 102 is driven through the field. The supplyline 404 may include a check valve 405 to prevent backflow of the liquid into the product tank 110.

[0049] The pump 402 is configured to provide the liquid through the supply line 404 to a supply valve 406 in a first manifold 408 (illustrated in a dashed box in FIG. 4A and FIG. 4B). The supply valve 406 may be located downstream of the pump 402 and may be in fluid communication with a flow control valve 410 and branches of the supply line 404. The supply valve 406 comprises an on / off valve configured to open and close.

[0050] Between the supply valve 406 and the flow control valve 410, the supply line 404 may branch to include a first branch 412 and a second branch 414. At least a portion of the liquid in the first branch 412 may be directed to a second manifold 418 and from the second manifold 418 to the supply line 404 proximate the nozzles 206. In some embodiments, regardless of the position of the flow control valve 410, at least a portion of the liquid in the first branch 412 may be directed to the supply line 404 proximate the nozzles 206 at the boom arm 202. The liquid in the second branch 414 may be provided to the flow control valve 410.

[0051] Within the first manifold 408, the supply line 404 may further include a third branch 416. The flow control valve 410 may be in fluid communication with and configured to receive liquid from the second branch 414. The flow control valve 410 may be configured to receive liquid from the third branch 416 or provide liquid to the third branch 416, depending on the position of the flow control valve 410. A direction of flow in the third branch 416 may depend on the position of the flow control valve 410 (and whether liquid in the liquid distribution system 204 is being sprayed from the nozzles 206 or recirculated in a recirculation line 420).

[0052] In some embodiments, the liquid from the supply line 404 (e.g., from the first branch 412 and the third branch 416) enters the second manifold 418, which may distribute the liquid to multiple groups of nozzles 206 at the boom arm 202 (FIG. 2). For example, and as shown in FIG. 4A, the supply line 404 may split into two portions or branches, which each supply groups of nozzles 206 (two groups of four nozzles 206 depicted in FIG. 4A and FIG. 4B). It should be understood that the second manifold 418 may split the supply line 404 into any number of branches, and each branch may supply any number of nozzles 206 independent ofother branches. Individual control of different branches of nozzles 206 may be useful for spraying near edges of fields, in irregularly shaped fields, etc.

[0053] At the boom arm 202, the liquid may be dispensed through the nozzles 206. In some embodiments, the nozzles 206 comprise pulse width modulation (PWM) valves including a solenoid. The nozzles 206 may each receive an operating signal, such as to open or close, from a control environment 434 located in the operator cab 106 (FIG. 1). When a nozzle 206 is open, liquid may flow out of the nozzle 206. Accordingly, in some embodiments, the nozzles 206 are electronically controlled.

[0054] The recirculation line 420 may be fluidly coupled to the product tank 110 and configured to return liquid in the supply line 404 to the product tank 110. The recirculation line 420 may be configured to be in fluid communication with the nozzles 206 by means of a fluid line 422 in a flow path between the flow control valve 410 and the supply line 404 proximate the nozzles 206. The direction of flow in the fluid line 422 may depend on a position of the flow control valve 410 and a recirculation valve 424. For example, depending on the position of the flow control valve 410, the liquid in the fluid line 422 may be directed from the flow control valve 410 to the nozzles 206 and out of the nozzles 206 (e.g., during a spraying operation); or the liquid in the fluid line 422 may be directed from the flow control valve 410 to the recirculation line 420.

[0055] The recirculation valve 424 may be located at an intersection of the fluid line 422 and the recirculation line 420. The recirculation valve 424 may comprise an on / off valve configured to open and close. For example, in the open position, the recirculation valve 424 facilitates flow of liquid through the recirculation line 420 and back to the product tank 110 during a recirculation operation. During a spraying operation, the recirculation valve 424 may be in the closed position. In some embodiments, the recirculation line 420 includes a check valve 421 to prevent backflow of the liquid from the recirculation line 420 back through the recirculation valve 424.

[0056] The flow control valve 410 may include a three-way valve. In the liquid distribution system 204, the flow control valve 410 may be configured to rotate to change a position of the flow control valve 410 between three different configurations (e.g., each havinga different flow through the flow control valve 410). In some embodiments, the flow control valve 410 comprises a three-position three-way valve. FIG. 5 shows an example of a three-way valve 500 that may be used as the flow control valve 410. The three-way valve 500 may include a rotatable element 502 (e.g., a ball) configured direct a fluid path of the liquid passing through the three-way valve 500. The three-way valve 500 may include a first passage 504 (e.g., a first port) and a second passage 506 (e.g., a second port) that are each approximately the same size as the supply line 404 (e.g., as each of the second branch 414, the third branch 416, and the fourth branch 428). The three-way valve 500 may further include a third passage 508 (e.g., a third port) that is relatively smaller than the first passage 504 and the second passage 506 (and the supply line 404). The third passage 508 may comprise a restriction such that a flowrate of liquid through the third passage 508 is less than the flowrate of liquid through the first passage 504 and the second passage 506. The third passage 508 may be defined by an orifice and may comprise an orificed port.

[0057] Referring to FIG. 4A, during a spraying operation, the supply valve 406 may be open, and the recirculation valve 424 may be closed. In addition, the flow control valve 410 may be positioned such that the first passage 504 (FIG. 5) and the second passage 506 (FIG. 5) are in line and in fluid communication with the respective third branch 416 and the fluid line 422; and the third passage 508 is not in fluid communication with the supply line 404 (e.g., the third passage 508 dead ends in the supply line 404). The second branch 414 may dead end at the flow control valve 410 during a spraying operation. For clarity and ease of understanding the description, the flow control valve 410 is illustrated in dashed circle 411 in the figures. When the flow control valve 410 is positioned such that liquid does not flow through a liquid line (e.g., the second branch 414, the third branch 416, or the fluid line 422) to or from the flow control valve 410, the liquid line is illustrated as disconnected from the flow control valve 410 and connected to the dashed circle 411. Of course, it will be understood that the flow control valve 410 is physically connected to each of the liquid lines, and that the position of the flow control valve 410 (e.g., the position of a ball inside of the flow control valve 410) affects whether liquid in the liquid line flows to and / or from the flow control valve 410 through the liquid line.

[0058] During the spraying operation, liquid may flow from the pump 402 through the supply valve 406. The liquid may flow through the first branch 412 and to the second manifold 418. From the second manifold 418, the liquid flows to the nozzles 206. In addition, at the intersection between the first branch 412 and the third branch 416, a portion of the liquid flows through the third branch 416 to the flow control valve 410, and through the flow control valve 410 to the fluid line 422. The liquid from the fluid line 422 flows to the nozzles 206. Accordingly, during the spraying process, the liquid flows from the flow control valve 410 to the nozzles 206 through the fluid line 422, as well as by means of the second manifold 418.

[0059] Referring to FIG. 4B, during a recirculation operation, the supply valve 406 may be open, and the flow control valve 410 may be positioned such that the first passage 504 (FIG. 5) and the second passage 506 (FIG. 5) are in line and in fluid communication with the respective second branch 414 and the third branch 416; and the third passage 508 is in line with and in fluid communication with the fluid line 422. The recirculation valve 424 may be open. The liquid may flow from the pump 402, through the supply valve 406, and each of the first branch 412 and the second branch 414. At the flow control valve 410, the liquid may flow from the second branch 414 to the third branch 416 towards the intersection of the first branch 412 and the third branch 416 and to the second manifold 418. The liquid flows from the second manifold 418 to the nozzles 206, as described above.

[0060] During the recirculation operation, a portion of the liquid at the flow control valve 410 passes through the third passage 508 (FIG. 5) to the fluid line 422. The fluid from the fluid line 422 flows through the recirculation valve 424 to the recirculation line 420. In addition, the fluid from the supply line 404 at the boom arm 202 (FIG. 2) flows past the nozzles 206 and towards the recirculation line 420 through the fluid line 422. Accordingly, depending on whether a spraying operation or a recirculation operation is being performed, and depending on the position of the flow control valve 410 (and the other valves, such as the recirculation valve 424), a direction of fluid flow through the fluid line 422 may either be towards the nozzles 206 or towards the recirculation line 420.

[0061] The recirculation operation may be used to flush or prime the liquid throughout the liquid distribution system 204, removing air bubbles and diluting any residue ofliquids used in prior operations. For example, during a recirculation operation, the liquid flows through the recirculation line 420 back to the product tank 110. This pushes any air in the supply line 404 to the product tank 110 and fills the plumbing with liquid (e.g., primes the liquid distribution system 204). When the liquid distribution system 204 is primed, the liquid distribution system 204 may be ready to dispense liquid from the nozzles 206 without delay and without fluctuations in flow that can be caused by air bubbles in the supply line 404.

[0062] The liquid distribution system 204 may further include one or more air supply lines, such as a first air supply line 430 and a second air supply line 432. The first air supply line 430 may be connected to the supply line 404, such as proximate the supply valve 406, and the second air supply line 432 may be connected to the recirculation line 420, such as proximate the recirculation valve 424 (e.g., between the recirculation valve 424 and the check valve 421).

[0063] When a spraying operation is complete, the first air supply line 430 may be connected to a source of pressurized air (e.g., a compressor), which may be used to purge the liquid distribution system 204 of liquid. FIG. 4C is a simplified schematic illustrating how the liquid distribution system 204 may be configured during a purging operation. When purging the liquid distribution system 204 with the first air supply line 430, the supply valve 406 may be closed, the flow control valve 410 may be positioned such that the first passage 504 (FIG. 5) is closed, the second passage 506 (FIG. 5) is in fluid communication with the second branch 414, and the third passage 508 (FIG. 5) is in fluid communication with the third branch 416. The recirculation valve 424 may be open. Compressed air may be provided to the first air supply line 430 to direct the liquid in the supply line 404 and at the boom arm 202 (FIG. 2) proximate the nozzles 206 back to the product tank 110 through the recirculation line 420. To prevent flow through the nozzles 206 during such a purge, the nozzles 206 may be maintained in the closed position.

[0064] In other embodiments, the recirculation valve 424 may be closed and compressed air may be provided to the second air supply line 432 to direct liquid in the recirculation line 420 back to the product tank 110. After the liquid in the recirculation line 420 is returned to the product tank 110, the supply valve 406 may be closed and compressed airmay be provided to the first air supply line 430 while the recirculation valve 424 is closed such that liquid in the supply line 404 is sprayed out of the nozzles 206.

[0065] The liquid distribution system 204 enables recirculation of the liquid back to the product tank 110 in order to prime the supply line 404 and nozzles 206 before spraying operations, without wasting liquid. The recirculation may push any air from the supply line 404 or nozzles 206 back to the product tank 110 in order to spray consistently and accurately. In addition, the liquid distribution system 204 may be used to retrofit an existing crop sprayer, which typically includes the product tank 110, the pump 402, the supply line 404, and the nozzles 206. The supply line 404 of a conventional crop sprayer may be capped at the end of a line of nozzles 206. To retrofit the crop sprayer, the end of each line of nozzles 206 can be uncapped, and the recirculation line 420, is added to each uncapped end to direct the liquid from the nozzles 206 to the product tank 110. In addition, the first manifold 408 may be installed downstream of the supply valve 406. For example, the supply line 404 may be cut downstream of the supply valve 406 to connect an end of the first manifold 408 to the supply line 404 and another end of the first manifold 408 to the portion of the supply line 404 configured to direct the liquid to the second manifold 418 and to the nozzles 206.

[0066] Another benefit of the liquid distribution system 204 that includes the first manifold 408 is that there may be no dead ends in the liquid distribution system 204 (such as during a recirculation operation) because liquid can flow in complete loops. For example, there may be no dead zones between the supply valve 406 and the recirculation line 420 during recirculation operations, which may otherwise be present in existing crop sprayers. Dead zones during recirculation may result in poor fluid agitation during recirculation. Thus, it may be relatively easier to clean the entire liquid distribution system 204 (e.g., by putting clean water in the product tank 110 and operating the pump 402 during a recirculation operation). Keeping the liquid distribution system 204 clean may prolong the life of the components of the liquid distribution system 204. Furthermore, recirculating the liquid when priming the supply line 404 and nozzles 206 may prevent waste of the liquid, and thus, may lead to lower costs of using the crop sprayer 102, 302 as compared to conventional sprayers.

[0067] An operator may control the liquid distribution system 204 via a control environment 434 in the operator cab 106 (FIG. 1) or in an associated vehicle (e.g., the tractor 308 in FIG. 3). The control environment 434 may be substantially similar to that described in U.S. Provisional Patent Application 63 / 499,162, "Liquid Distribution Systems, Crop Sprayers, and Related Methods," filed April 28, 2023. For example, the control environment 434 may include switches 436 to open and close the respective supply valve 406 and the recirculation valve 424, and to position (orient) the flow control valve 410. In addition, the control environment 434 may include a display 442 to provide operator feedback. The switches 436 may each be a rocker switch that includes one or more indicators, such as a light 438 to indicate that the liquid distribution system 204 is configured for recirculation, and a light 440 to indicate flow as detected by a flow indicator. The control environment 434 may be in operable communication with each of the supply line 404 and the recirculation line 420. For example, the control environment 434 may receive a signal indicative of a flow in at least one of (e.g., each of) the supply line 404 and the recirculation line 420, and may provide for example, a historical chart and / or an instantaneous reading of the flow through the respective supply line 404 and the recirculation line 420. The operator may use such information to determine whether the liquid distribution system 204 is operating as expected.

[0068] FIG. 6A is a simplified schematic illustrating a liquid distribution system 600 during a spraying operation. FIG. 6B is a simplified schematic illustrating how the liquid distribution system 600 may be configured during a recirculation operation. The liquid distribution system 600 may be substantially the same as the liquid distribution system 204, except that the liquid distribution system 600 includes a flow control valve 602 configured to rotate between only two positions; and the liquid distribution system 600 includes an additional valve 604 between the flow control valve 602 and the fluid line 422. A dashed circle 603, similar to dashed circle 411 is illustrated surrounding the flow control valve 602.

[0069] The liquid distribution system 600 includes a first manifold 606 comprising the flow control valve 602, the additional valve 604, and the supply valve 406. The flow control valve 602 may be substantially similar to the flow control valve 410 (FIG. 4A, FIG. 4B), except that in the liquid distribution system 600, the flow control valve 602 is configured to rotatebetween only two positions. The additional valve 604 includes an on / off valve and is located at an intersection of the fluid line 422 and a fourth branch 608 of the supply line 404. The additional valve 604 is proximate the recirculation valve 424. The fourth branch 608 of the supply line 404 is in a flow path between the flow control valve 410 and the additional valve 604. The additional valve 604 is located in a flow path between the flow control valve 602 and each of the nozzles 206 and the recirculation line 420 (depending on the configuration of the liquid distribution system 204). In some embodiments, the position of the additional valve 604 is adjusted during various air purging operations in which liquid from the supply line 404 is either sprayed out of the nozzles 206, or circulated back to the product tank 110.

[0070] During a spraying operation, the flow control valve 602 may be positioned in the orientation illustrated in FIG. 6A such that the second branch 414 dead ends at the flow control valve 602, the first passage 504 (FIG. 5) is in fluid communication with the third branch 416, the second passage 506 (FIG. 5) is in fluid communication with the fourth branch 608, and the third passage 508 (FIG. 5) is not in fluid communication with any portion of the supply line 404. As illustrated in FIG. 6B, during a recirculation operation, the position of the flow control valve 602 is switched such that the first passage 504 is in fluid communication with the second branch 414, the second passage 506 is in fluid communication with the third branch 416, and the third passage 508 is in fluid communication with the fourth branch 608.

[0071] During a purge operation, the first air supply line 430 may be connected to a source of pressurized air to purge the liquid distribution system 600 of liquid. For example, the supply valve 406 and the additional valve 604 may be closed, the recirculation valve 424 may be open, and the flow control valve 602 may be in the position illustrated in FIG. 6B. Compressed air may be provided to the first air supply line 430 to direct the liquid in the supply line 404 and at the boom arm 202 (FIG. 2) proximate the nozzles 206 back to the product tank 110 through the recirculation line 420. To return liquid from the recirculation line 420 to the product tank 110, the recirculation valve 424 is closed and pressurized air is provided to the second air supply line 432.

[0072] While the liquid distribution system 204, 600 has been described and illustrated as including the first manifold 408 comprising the flow control valve 410, 602comprising a three-way valve and the additional valve 604 (FIG. 6A, FIG. 6B), the disclosure is not so limited. FIG. 7A is a simplified schematic illustrating a liquid distribution system 700 during a spraying operation. FIG. 7B is a simplified schematic illustrating how the liquid distribution system 700 may be configured during a recirculation operation. In FIG. 7A and FIG. 7B, arrows have been used for convenience to illustrate a direction of liquid flow through the liquid distribution system 700 during the respective spraying and recirculation operations. The liquid distribution system 700 may be used in the crop sprayer 102, 302.

[0073] The liquid distribution system 700 may be substantially the same as the liquid distribution system 204, 600, except that the liquid distribution system 700 includes a first manifold 702 including the flow control valve 602 and a recirculation valve 704. The recirculation valve 704 may comprise a three-way valve configured to be positioned in three different positions. For clarity and ease of understanding the description, a dashed circle 705 is illustrated surrounding the recirculation valve 704. When the recirculation valve 704 is positioned such that liquid does not flow through a liquid line (e.g., the recirculation line 420, a fourth branch 428, the fluid line 422) to or from the recirculation valve 704, the liquid line is illustrated as disconnected to the recirculation valve 704 and connected to the dashed circle 705. Of course, it will be understood that the recirculation valve 704 is physically connected to each of the liquid lines, and that the position of the recirculation valve 704 affects whether liquid in the liquid lines flows to and / or from the recirculation valve 704. In some embodiments, the recirculation valve 704 may be different than the flow control valve 602. For example, the recirculation valve 704 may not include a third passage 508 (FIG. 5) having a smaller diameter than a first passage and a second passage. Rather, each of the passages of the recirculation valve 704 may be substantially the same size.

[0074] With reference to FIG. 7A, during a spraying operation, the flow control valve 602 may be positioned in the same orientation as described above with reference to FIG. 4A, and the recirculation valve 704 may be positioned such that liquid does not flow to the recirculation line 420. The recirculation valve 704 may be positioned such that liquid from the supply line 404 passing through the third branch 416, through the flow control valve 602, and to the fourth branch 428 flows through the recirculation valve 704 and to the fluid line 422 tothe supply line 404 at the boom arm 202 and the nozzles 206. In such embodiments, one of the ports of the recirculation valve 704 is closed (e.g., not in fluid communication with a fluid line, such as the fluid line 422, the recirculation line 420, or the fourth branch 428).

[0075] Referring to FIG. 7B, during a recirculation operation, the position of the flow control valve 602 may be adjusted to be similar to that described above with reference to FIG. 4B, and the recirculation valve 704 may be rotated 180° such that the recirculation line 420 is in fluid communication with the recirculation valve 704. For example, the recirculation valve 704 may be positioned to be in fluid communication with the fourth branch 428, the fluid line 422, and the recirculation line 420.

[0076] Liquid in the supply line 404 may be purged and flowed back to the product tank 110 by providing pressurized air to the first air supply line 430. FIG. 7C is a simplified schematic illustrating how the liquid distribution system 700 may be configured during a purging operation. The supply valve 406 may be closed, the flow control valve 602 may be in the position illustrated in FIG. 7C, and the recirculation valve 704 may be positioned such that liquid does not flow through the recirculation valve 704 by means of the flow control valve 602. For example, the recirculation valve 704 may be positioned such that liquid does not flow to the recirculation valve 704 by means of the fourth branch 428. The recirculation valve 704 may be positioned such that liquid flows from the fluid line 422 through the recirculation valve 704 and to the recirculation line 420. In some embodiments, the liquid in the recirculation line 420 may be returned to the product tank 110, such as by providing pressurized air to the second air supply line 432. The recirculation valve 704 may be positioned such that the recirculation line 420 is in fluid communication with the fluid line 422 and the fourth branch 428 and the liquid in the supply line 404 flows from the fourth branch 428, through the recirculation valve 704, to the fluid line 422 and the supply line 404 at the boom arm 202. After returning the liquid to the product tank 110, the liquid in the supply line 404 may be purged out of the nozzles 206, such as by closing the supply valve 406 and positioning the flow control valve 602 in the position illustrated in FIG. 7A. Pressurized air may be provided to the first air supply line 430 to push liquid through the supply line 404 and out of the nozzles 206.

[0077] FIG. 8A is a simplified schematic illustrating a liquid distribution system 800 during a spraying operation. FIG. 8B is a simplified schematic illustrating how the liquid distribution system 800 may be configured during a recirculation operation. In FIG. 8A and FIG. 8B, arrows have been used for convenience to illustrate a direction of liquid flow through the liquid distribution system 800 during the respective spraying and recirculation operations. The liquid distribution system 800 may be used in the crop sprayer 102, 302.

[0078] The liquid distribution system 800 may be substantially the same as the liquid distribution systems 204, 600, 700, except that the liquid distribution system 800 may include a different first manifold and flow control valve than the liquid distribution systems 204, 600, 700. The liquid distribution system 800 includes a first manifold 802 including a flow control valve 804 comprising a four-way valve. The first manifold 802 may further include a recirculation valve 806.

[0079] The flow control valve 804 may be in fluid communication with the second branch 414, the third branch 416, and the fluid line 422. In addition, the flow control valve 804 may be in fluid communication with a fifth branch 808. Depending on whether a spraying operation or a recirculation operation is being performed, a direction of liquid flow through the fluid line 422, the third branch 416, and the fifth branch 808 may be different.

[0080] With reference to FIG. 8A, during a spraying operation, the flow control valve 804 may be positioned to direct liquid from the third branch 416 to the fluid line 422 and liquid from the second branch 414 to the fifth branch 808. The liquid in the fifth branch 808 may flow to the fluid line 422 and to the nozzles 206 at the boom arm 202. In addition, the liquid at the first branch 412 may flow to the second manifold 418 and to the nozzles 206 at the boom arm 202.

[0081] Referring to FIG. 8B, during a recirculation operation, the position of the flow control valve 804 may be adjusted such that liquid flows from the second branch 414 through the flow control valve 804 to the third branch 416, and from the third branch 416 to the second manifold 418. From the second manifold 418, the liquid flows to the supply line 404 at the boom arm 202, as described above. In addition, the fluid in the supply line 404 at the boom arm202 flows to the fluid line 422, a portion of which flows through the flow control valve 804 to the fifth branch 808 and to the recirculation valve 806.

[0082] Liquid in the supply line 404 may be purged and flowed back to the product tank 110 by providing pressurized air to the first air supply line 430. The supply valve 406 may be closed, the flow control valve 804 may be in the position illustrated in FIG. 8B, and the recirculation valve 806 may be open. In such a configuration, the pressurized air may cause the liquid in the supply line 404 to flow through the second manifold 418, through the supply line 404 at the boom arm 202 to the fluid line 422, and from the fluid line 422 to the recirculation line 420 (either directly and / or through the flow control valve and the fifth branch 808). In some embodiments, the liquid in the recirculation line 420 may be recycled back to the product tank 110, such as by closing the recirculation valve 806 and providing pressurized air to the second air supply line 432. After returning the liquid to the product tank 110, the liquid in the supply line 404 (if any) may be purged out of the nozzles 206, such as by closing the supply valve 406 and positioning the flow control valve 804 in the position illustrated in FIG. 8A. Pressurized air may be provided to the first air supply line 430 to push liquid through the supply line 404 and out of the nozzles 206.

[0083] FIG. 9 is a simplified flow chart illustrating a method 900 of operating the crop sprayer 102 (FIG. 1) or the crop sprayer 302 (FIG. 3) in an agricultural field. The method 900 includes pumping liquid from a product tank through a flow control valve to a fluid line, and from each of a supply line and the fluid line to the a, as shown in act 902. Pumping the liquid from the product tank through the flow control valve to the fluid line includes directing the fluid through the flow control valve to the fluid line and the boom. In addition, the fluid may be flowed through the supply line to the second manifold and to the boom. In some embodiments, act 902 includes spraying the liquid out of the nozzles.

[0084] The method 900 includes changing a position of the flow control valve, as shown in act 904. The position of the flow control valve may be changed to a recirculation position, as described above with reference to each of FIG. 4B, FIG. 6B, FIG. 7B, and FIG. 8B.

[0085] The method 900 may further include pumping additional liquid through the flow control valve and to the boom, and from the boom through the fluid line to a recirculationline, as shown in act 906. For example, the fluid may flow to the recirculation line as described above with reference to each of FIG. 4B, FIG. 6B, FIG. 7B, and FIG. 8B.

[0086] All references cited herein are incorporated herein in their entireties. If there is a conflict between definitions herein and in an incorporated reference, the definition herein shall control.

[0087] While the present disclosure has been described herein with respect to certain illustrated embodiments, those of ordinary skill in the art will recognize and appreciate that it is not so limited. Rather, many additions, deletions, and modifications to the illustrated embodiments may be made without departing from the scope of the disclosure as hereinafter claimed, including legal equivalents thereof. In addition, features from one embodiment may be combined with features of another embodiment while still being encompassed within the scope as contemplated by the inventors. Further, embodiments of the disclosure have utility with different and various machine types and configurations.

Claims

CLAIMSWhat is claimed is:

1. A liquid distribution system of a crop sprayer, comprising: a product tank configured to contain a liquid; a pump in fluid communication with the product tank; at least one nozzle carried by a boom and configured to receive the liquid from the pump through a supply line; a recirculation line connecting the at least one nozzle to the product tank; and a flow control valve in fluid communication with the supply line and a fluid line configured to receive the liquid from the flow control valve, the flow control valve comprising one of a three-way valve or a four-way valve, a position of the flow control valve configured to change between a spraying operation and a recirculation operation wherein: during the spraying operation, the fluid line is configured to receive liquid from the flow control valve and direct the liquid to the at least one nozzle; and during the recirculation operation, the fluid line is configured to receive liquid from the supply line proximate the at least one nozzle and direct the liquid to the recirculation line.

2. The liquid distribution system of claim 1, wherein the flow control valve is between the supply line and the at least one nozzle.

3. The liquid distribution system of claim 1 or claim 2, further comprising an additional valve configured to direct the liquid from the fluid line to the recirculation line or the at least one nozzle based on a position of the additional valve.

4. The liquid distribution system of claim 3, wherein the additional valve comprises a three-way valve in fluid communication with the flow control valve, the fluid line, and the recirculation line.

5. The liquid distribution system of claim 3 or claim 4, wherein the additional valve is located at an intersection between the fluid line and the recirculation line.

6. The liquid distribution system of claim 4 or claim 5, wherein the additional valve is in a flow path between the flow control valve and the at least one nozzle.

7. The liquid distribution system of claims 5 or 6, wherein the additional valve is in fluid communication with the flow control valve, the liquid distribution system further comprising a recirculation valve within the recirculation line proximate the intersection between the fluid line and the recirculation line.

8. The liquid distribution system of any one of claims 1 through 7, wherein the at least one nozzle is in a flow path between the supply line and the recirculation line.

9. The liquid distribution system of any one of claims 1 through 8, wherein the flow control valve comprises a three-way valve, the three-way valve including two open ports and a third port having a smaller orifice than the two open ports.

10. The liquid distribution system of claim 9, wherein the three-way valve is configured to induce a larger pressure drop between the supply line and the fluid line than between the supply line and the at least one nozzle.

11. The liquid distribution system of any one of claims 1 through 3 or claims 8 through 10, wherein the flow control valve comprises a four-way valve.

12. The liquid distribution system of any one of claims 1 through 11, wherein the fluid line is in a flow path between the flow control valve and the at least one nozzle.

13. The liquid distribution system of any one of claims 1 through 12, wherein the fluid line is in a flow path between the flow control valve and the recirculation line.

14. The liquid distribution system of any one of claims 1 through 13, further comprising an air supply line between the product tank and the flow control valve, the air supply line configured to receive pressurized air to return liquid within the supply line, the at least one nozzle, and the recirculation line to the product tank.15 The liquid distribution system of any one of claims 1 through 13, further comprising an air supply line in the recirculation line and configured to purge the recirculation line of liquid.

16. A crop sprayer comprising the liquid distribution system of any one of claims 1 through 15, the crop sprayer comprising: wheels; a chassis supported by the wheels; and an engine configured to propel the crop sprayer.

17. A method of operating a crop sprayer comprising a product tank, a pump, a supply line, a boom carrying at least one nozzle configured to receive liquid from the supply line, a recirculation line connecting the at least one nozzle to the product tank, a flow control valve in fluid communication with the supply line, and a fluid line between the at least one nozzle and the recirculation line, the method comprising: pumping liquid from the product tank through the supply line to the flow control valve, from the flow control valve to the fluid line, and from each of the supply line and the fluid line to the at least one nozzle; changing a position of the flow control valve; and pumping additional liquid through the flow control valve and to the at least one nozzle, and from the at least one nozzle through the fluid line to the recirculation line.

18. The method of claim 17, wherein changing a position of the flow control valve comprises changing a position of a three-way valve or a four-way valve.

19. The method of claim 17 or claim 18, further comprising changing a position of a second valve when pumping the additional liquid from the at least one nozzle through the fluid line to the recirculation line to recirculate the additional liquid.

20. The method of any one of claims 17 through 19, further comprising purging the supply line with compressed air to return the liquid in the supply line to the product tank.

Images