Liquid distribution systems, crop sprayers and related methods

Description

1 / 22 Liquid distribution systems, crop sprayers and related methods CROSS-REFERENCE TO RELATED REQUESTS

[001] This application claims the benefit of the filing date of U.S. Provisional Patent Application 63 / 499,162, “Liquid Distribution Systems, Crop Sprayers, and Related Methods,” filed April 28, 2023, the full disclosure of which is incorporated herein by reference. The subject matter of this application is also related to the subject matter of International Patent Application PCT / IB2023 / 057023, “Liquid Distribution Systems, Crop Sprayers, and Related Methods,” filed July 7, 2023. FIELD

[002] The embodiments of the present disclosure relate generally to piping for a boom arm on a crop sprayer and, more particularly, to the liquid distribution system connecting a plurality of spray nozzles along the boom arm to a liquid supply line. BACKGROUND

[003] The high yields of modern agribusiness crops may require the application of fertilizers, pesticides, and / or herbicides. The dispersal of these chemicals across large cultivated fields requires specialized machinery mounted on or towed by a vehicle. An example of such machinery is the self-propelled sprayer.

[004] 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 products such as fertilizers, pesticides, and / or herbicides. The boom arms extend out from the sides of the chassis. The boom piping contains supply lines and nozzles spaced at Petition 870250088304, dated 09 / 29 / 2025, pp. 101 / 140 2 / 22 of the length of the boom arms at a spacing distance corresponding to the spray pattern of the nozzles. In operation, as the crop sprayer traverses the field, liquid is pumped from the tank through 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 can vary from, for example, 6 meters (18 feet) to 46 meters (150 feet), but shorter or longer booms are possible. Boom arms typically swing inward for road transport and outward for field spraying operations.

[005] Conventionally, nozzles are connected in series in such a way that the product flows through a tube and / or hose from one nozzle to another. Lances have been of the “wet lance” type, where the lance comprises a frame member with a tube mounted on it, and the liquid passes through the tube to nozzles mounted on the tube and liquidly connected to it, or a “dry lance” type, where the nozzles are mounted on the frame member and the liquid passes to the nozzles through a hose that is connected between the nozzles. The nozzles are fixed to the tube or frame with supports at desired intervals along the lance arm.

[006] When a sprayer is used for the first time to dispense a particular product, the product may be discharged through the tube or hose to each nozzle to fill the entire piping system with the product. This can help remove air bubbles and ensure that any previous products are purged from the system. To prevent uneven product distribution, this discharge 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 lance to ensure that all of the Petition 870250088304, dated 09 / 29 / 2025, pp. 102 / 140 3 / 22 air exits the lance so that the liquid product can be dispensed consistently and uniformly from each of the nozzles.

[007] Some methods for discharging or purging spraying systems are disclosed in International Patent Application Publication WO / 2022 / 243750 A1, “Liquid Distribution Systems for Crop Sprayers, and Related Methods”, published on November 24, 2022. BRIEF SUMMARY

[008] In some embodiments, a liquid delivery system for 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 lance and configured to receive liquid from the pump via a supply line, a recirculation line connecting at least one nozzle to the product tank, a pressure sensor configured to measure the liquid pressure in the supply line, a control environment configured to control the pump, and a pressure sensor simulator configured to provide a signal to the control environment corresponding to a simulated liquid pressure when the liquid delivery system is in a recirculation mode. The recirculation line includes an adjustable restriction.The restriction is configured to vary the liquid pressure at at least one nozzle when the liquid distribution system is in recirculation mode.

[009] The pressure sensor simulator may include a voltage divider circuit. The pressure sensor simulator may be part of an electrical harness. The pressure sensor simulator may include a switch configured to switch an output from the pressure sensor simulator between a real pump pressure signal and a simulated pressure signal.

[010] The liquid distribution system may also include a Petition 870250088304, dated 09 / 29 / 2025, pp. 103 / 140 4 / 22 check valve in the recirculation line, where the check valve is configured to prevent flow from the product tank to at least one nozzle through the recirculation line.

[011] The liquid distribution system may also include a flow indicator configured to detect flow through the recirculation line.

[012] At least one nozzle may include a first plurality of nozzles and a second plurality of nozzles, and each plurality of nozzles is configured to receive liquid from the pump independently of the other plurality of nozzles.

[013] At least one nozzle may include a check valve to enable flow through at least one nozzle when the pressure in at least one nozzle exceeds a limit.

[014] The liquid distribution system may also include a control system configured to control the restriction, where when the restriction is in a first position, the restriction is configured to have a first pressure drop, and where when the restriction is in a second position, the restriction is configured to have a second pressure drop greater than the first pressure drop.

[015] A crop sprayer includes a chassis and the liquid distribution system carried by the chassis.

[016] In some embodiments, the crop sprayer includes a chassis-mounted engine, the engine configured to propel the chassis across an agricultural field. The crop sprayer may also include a chassis-mounted operator cab.

[017] In other forms, the crop sprayer includes a hitch configured to attach the chassis to a tractor. Petition 870250088304, dated 09 / 29 / 2025, pp. 104 / 140 5 / 22

[018] An embodiment includes a method of operating a crop sprayer. The crop sprayer itself includes a product tank, a pump, a restriction, a plurality of nozzles spaced along a lance, a recirculation line, and a control environment. The method includes providing a signal corresponding to a simulated liquid pressure to the control environment, pumping liquid through the pump, the restriction, at least one of the nozzles, and the recirculation line to the product tank without spraying the liquid from at least one of the nozzles while the control environment receives the signal corresponding to the simulated liquid pressure, and adjusting the restriction to decrease a pressure drop associated with the restriction.The method also includes providing a signal corresponding to an actual pump pressure to the control environment, pumping the liquid through the pump, the restriction, and at least one of the nozzles to spray the liquid from at least one of the nozzles while the control environment receives the signal corresponding to the actual pump pressure.

[019] The plurality of nozzles can be configured to spray only when the liquid is above a limit pressure, and pumping liquid through the pump, restriction, nozzles and recirculation line to the product tank without spraying the liquid from the plurality of nozzles includes maintaining a pressure in the nozzles below the limit pressure.

[020] Pumping liquid through the pump, the restriction and at least one of the nozzles to spray liquid from at least one of the nozzles may include dispensing liquid from at least one of the nozzles while propelling the lance across an agricultural field.

[021] One aspect includes an improvement in a liquid distribution system of a crop sprayer. The liquid distribution system includes a product tank configured to hold a liquid, a pump Petition 870250088304, dated 09 / 29 / 2025, pp. 105 / 140 6 / 22 in fluid communication with the product tank, at least one nozzle carried by a lance and configured to receive liquid from the pump, a pressure sensor configured to measure the pressure of the liquid transmitted to the lance by the pump, and a control environment configured to control the pump. The improvement includes a recirculation line connecting at least one nozzle to the product tank, an adjustable restriction configured to pass liquid from the pump to at least one nozzle, and a pressure sensor simulator configured to provide a simulated liquid pressure to the control environment when the liquid dispensing system is in recirculation mode. The restriction is configured to vary the liquid pressure at at least one nozzle when the liquid dispensing system is in recirculation mode.

[022] The switch can be controlled by activating the recirculation mode.

[023] The liquid distribution system may also include a manifold configured to receive liquid from the pump and distribute the liquid to each of the first plurality of nozzles and the second plurality of nozzles.

[024] Other technical attributes may be readily apparent to a person skilled in the art from the figures, descriptions and claims that follow. BRIEF DESCRIPTION OF THE DRAWINGS

[025] Although the descriptive report concludes with claims specifically pointing out and distinctly claiming what are considered embodiments of the present disclosure, several attributes and advantages can be more readily verified from the following description of exemplary embodiments when read in conjunction with the accompanying drawings, in which: Petition 870250088304, dated 09 / 29 / 2025, pp. 106 / 140 7 / 22 FIG. 1 illustrates an agricultural vehicle in the form of a self-propelled crop sprayer; FIG. 2 illustrates a portion of a spray lance from the crop sprayer shown in FIG. 1; FIG. 3 is a simplified top view of another agricultural vehicle, in the form of a crop sprayer towed by a tractor; and FIG. 4 is a simplified diagram of an application system that can be used on the agricultural vehicle shown in FIG. 1 or FIG. 3; FIG. 5A is a simplified cross-section of a possible constraint that can be used in the application system of FIG. 4; FIG. 5B is a simplified cross-section of the constraint in FIG. 5A in a different position; FIG. 6 is a simplified view of one of the nozzles of the application system in FIG. 4; FIG. 7A is a simplified electrical circuit diagram illustrating a pressure sensor simulator; FIG. 7B is a simplified electrical circuit diagram illustrating the pressure sensor simulator of FIG. 7A in another operating position; and FIG. 8 is a simplified flowchart illustrating a method of operation for a crop sprayer. DETAILED DESCRIPTION

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

[027] The following description provides specific details of the modalities. Petition 870250088304, dated 09 / 29 / 2025, pp. 107 / 140 8 / 22 However, a person skilled in the art will understand that the disclosure methods can be practiced without employing many of these specific details. In fact, the disclosure methods can be practiced in conjunction with conventional techniques employed in the industry. Furthermore, the description provided below does not include all the elements to form a complete structure or set. Only those process acts and structures necessary to understand the disclosure methods 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 therefore not drawn to scale.

[028] As used in the present invention, the terms comprising, including, containing, characterized in that and grammatical equivalents thereof are inclusive or open terms that do not exclude additional elements or method steps not mentioned, but also include the more restrictive terms consisting of and consisting essentially of and grammatical equivalents thereof.

[029] As used in the present invention, the term may with respect to a material, structure, attribute or method indicates that such is contemplated for use in implementing an embodiment of the disclosure and such term is used in preference to the more restrictive term is, so as to prevent any implication that other compatible materials, structures, attributes and methods, usable in combination with the same, should or need to be excluded.

[030] As used in the present invention, 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 the operation of one or more of the structure and the apparatus in a manner Petition 870250088304, dated 09 / 29 / 2025, pp. 108 / 140 9 / 22 predetermined.

[031] As used in the present invention, the following singular forms a, “an” and “the” are intended to equally include the plural forms, unless the context clearly indicates otherwise.

[032] As used in the present invention, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[033] 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 and 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 front portion of the chassis 104 in front of the operator cab 106 or may be mounted on a rear 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 power to propel the crop sprayer 102 through a field on wheels or tracks, and may also provide power to spray liquids from the crop sprayer 102.

[034] The crop sprayer 102 additionally includes a product tank 110 for storing a liquid to be sprayed in the field. The liquid may include chemicals such as, but not limited to, herbicides, pesticides and / or fertilizers. The product tank 110 may be mounted on the chassis 104, or in front of or behind the operator's cab 106. The crop sprayer 102 may include more than one product tank 110 for storing different chemicals to be sprayed in the field. The stored chemicals may be dispersed by the crop sprayer 102. Petition 870250088304, dated 09 / 29 / 2025, pp. 109 / 140 10 / 22 one at a time or different chemicals can be mixed and dispersed together in a variety of mixtures.

[035] A boom 112 on the crop sprayer 102 is used to distribute liquid from the product tank 110 over a wide swath as the crop sprayer 102 is driven through the field. The boom 112 may include two or more sections that can be folded for transport on public roads and unfolded (i.e., to the position shown in FIG. 1) for field operations. FIG. 2 is a simplified perspective view of a section of 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 several spray nozzles 206 spaced along the boom 112. The liquid distribution system 204, which may be mounted on the boom 202, includes at least one supply line and one recirculation line connected to the product tank 110 (FIG. 1).

[036] FIG. 3 shows another crop sprayer 302 that can be used to deliver chemicals to agricultural crops in a field. The crop sprayer 302 is a traction-type sprayer that includes a chassis 304 carrying the product tank 110. The crop sprayer 302 has a hitch 306 configured to couple the chassis 304 to the tractor 308. The tractor 308 can therefore pull the crop sprayer 302 across the field, and the tractor 308 operator can also operate the crop sprayer 302 via a control system in the tractor 308 cab. The boom arms 202 can 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.

[037] FIG. 4 is a simplified diagram illustrating how the liquid distribution system 204 can be configured. A pump 402 in Petition 870250088304, dated 09 / 29 / 2025, pp. 110 / 140 11 / 22 Fluid communication with product tank 110 pumps liquid from product tank 110 through a supply line 404 to spray nozzles 206, which are mounted along the boom arm 202 (FIG. 2) at a pre-selected interval. Each spray nozzle 206 can dispense liquid onto the crops as the crop sprayer 102 is driven through the field.

[038] The liquid distribution system 204 also includes a recirculation line 406 connecting the nozzles 206 back to the product tank 110. One or more check valves 408 may be configured to prevent backflow through the recirculation line 406 from the product tank 110 back to the nozzles 206. That is, the check valves 408 may operate as one-way valves in the recirculation line 406, enabling flow only from the nozzles 206 to the product tank 110, but not the reverse. The check valve 408 may also operate to reduce the capacitance of the liquid distribution system 204, which may be caused by rubber hoses (i.e., in the supply line 404 and the recirculation line 406) expanding under pressure. Check valves 408 separate the recirculation line 406 from the supply line 404.Thus, when the pressure in the nozzles 206 is reduced to the point where the nozzles 206 are not spraying, the check valves 408 can maintain a certain pressure in the nozzles 206, such that the pressure does not need to be built up from scratch before spraying can begin.

[039] The recirculation line 406 may also include an on / off valve 410 configured to open and close. The on / off valve 410 may be, for example, a regular valve, a ball valve, a needle valve, a butterfly valve, or any other type of valve selected. When in the open position, liquid may flow through the supply line 404. Petition 870250088304, dated 09 / 29 / 2025, pp. 111 / 140 12 / 22 (driven by pump 402), through check valves 408, through the open on / off valve 410 and back to product tank 110. A flow indicator 412 may be in the recirculation line 406 and configured to determine if there is flow through the recirculation line 406. In some embodiments, the flow indicator 412 may be a flow meter configured to measure the amount of flow. In other embodiments, the flow indicator 412 may simply indicate the presence or absence of flow (i.e., on or off).

[040] The supply line 404 includes an adjustable restriction 414 before the nozzles 206 to adjust the liquid pressure at the nozzles 206. As used in the present invention, the term “adjustable restriction” means any device that can be adjusted between at least two positions, wherein at least one of the positions restricts flow through the supply line 404. The restriction 414 may include, for example, a butterfly valve, a ball valve, a pinch valve, or any other type of restriction. The restriction 414 may be configured to be adjustable from fully open (i.e., pressure drop close to zero along the restriction 414) to almost fully closed (i.e., large pressure drop along the restriction 414, but still allowing flow).In some embodiments, restriction 414 may be a ball valve that has been modified to have a small hole through the valve element that allows flow through in the position that would otherwise be closed. Thus, the valve can switch between fully open (i.e., little or no flow restriction) and relatively closed (i.e., relatively large flow restriction).

[041] FIGS. 5A and 5B show an example of a restriction 414 in the form of a ball valve. The restriction 414 includes a body 502 and a rotary adjustment element 504. The adjustment element 504 can be connected Petition 870250088304, dated 09 / 29 / 2025, pp. 112 / 140 13 / 22 to an actuator, handle, or other means to rotate the adjusting element 504. The adjusting element 504 can set holes or openings of different sizes. In the position shown in FIG. 5A, a passage 506a is formed through the restriction 414 which is approximately the same size as the supply line 404, and thus the restriction 414 offers little restriction to the liquid flow. In FIG. 5B, the adjusting element 504 has been rotated such that the resulting passage 506b is smaller (i.e., more restricted) than the supply line 404. Thus, the restriction 414 can cause a pressure drop. By adjusting the restriction 414, the liquid distribution system 204 can be used to spray liquid onto crops or recirculate liquid through the recirculation line 406, as discussed in further detail below.

[042] In some embodiments, the liquid may flow through a manifold 416 in the supply line 404, which may receive the liquid from the pump 402 and distribute the liquid to multiple groups of nozzles 206. For example, and as shown in FIG. 4, the supply line 404 may split into two portions or branches, each of which supplies groups of nozzles 206 (two groups of four nozzles 206 represented in FIG. 4). It should be understood that the supply line 404 may split into any number of branches, and each branch may supply any number of nozzles 206 independently of other branches. Individual control of different branches of the nozzles 206 may be useful for spraying near field edges, in irregularly shaped fields, etc.

[043] FIG. 6 is a simplified schematic view of one of the nozzles 206. As shown, the supply line 404 can pass through the nozzle 206. The nozzle 206 may also include a check valve 602 having a diaphragm 604 configured to enable liquid to flow through an orifice. Petition 870250088304, dated 09 / 29 / 2025, pp. 113 / 140 14 / 22 606 on the nozzle body only when the pressure in the supply line 404 exceeds a limit. Such nozzles 206 are generally used to prevent liquid from dripping from the nozzles 206 when the pump 402 is not operating. When the pump 402 is operating, but the pressure in the nozzles 206 is below the limit, the check valve 602 can still prevent flow out of the orifice 606, instead directing all the liquid through the nozzles 206 along the supply line 404 to the recirculation line 406.

[044] When restriction 414 is relatively closed and therefore the pressure at nozzles 206 is low, liquid distribution system 204 enables recirculation of the liquid back to product tank 110 in order to prepare the supply line 404 and nozzles 206 before spraying operations, without wasting liquid. Recirculation can push any air from the supply line 404 or nozzles 206 back to product tank 110 in order to spray consistently and accurately. When restriction 414 is relatively open and therefore the pressure at nozzles 206 is high, liquid distribution system 204 enables spraying of the liquid out of nozzles 206.

[045] The liquid distribution system 204 can be used to adapt 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 can be capped at the end of a nozzle line 206. To adapt the crop sprayer, the end of each nozzle line 206 can be uncapped, and the recirculation line 406 and, optionally, the check valves 408, are added to each uncapped end to direct the liquid from the nozzles 206 to the product tank 110. The on / off valve 410 and the flow indicator 412 can be added. Petition 870250088304, dated 09 / 29 / 2025, pp. 114 / 140 15 / 22 optionally. Restriction 414 is installed downstream of pump 402.

[046] If an operator decides that recirculation is necessary to prime lance 112 with product, the on / off valve 410 is opened, the restriction 414 is set to a relatively closed position, and pump 402 is switched on to allow liquid to flow from pump 402 through nozzles 206 and through recirculation line 406. Because restriction 414 is relatively closed, the pressure at nozzles 206 may be less than the limit pressure of nozzles 206, and the liquid simply flows through recirculation line 406 back to product tank 110. This pushes any air in the supply line 404 back into product tank 110 and ensures that the entire piping is full of liquid. When the operator wishes to apply liquid to the field, restriction 414 is relatively open, increasing the liquid pressure in nozzles 206. This pushes the liquid through diaphragms 604 to spray onto the field.

[047] Check valves 408 can reduce the time required to stop flow through nozzles 206 after closing restriction 414, due to reduced backflow in the recirculation line 406. Another benefit of including check valves 408 is that different sections of nozzles 206 (i.e., those aligned with each check valve 408) can be controlled separately. However, the liquid distribution system 204 can still operate without check valves 408.

[048] Another benefit of the liquid distribution system 204 which includes a recirculation line 406 is that there may be no dead ends in the liquid distribution system 204 because the liquid can flow in complete paths. Thus, it can be relatively easier to clean the entire liquid distribution system 204 (for example, by putting clean water into the product tank 110 and operating the pump 402 with the restriction 414 relatively closed). Keeping the liquid distribution system 204 clean can extend its life. Petition 870250088304, dated 09 / 29 / 2025, pp. 115 / 140 16 / 22 useful of the liquid distribution system components 204. In addition, liquid recirculation when preparing the supply line 404 and nozzles 206 can prevent liquid waste and thus can lead to lower operating costs for the crop sprayer 102, 302 compared to conventional sprayers.

[049] When liquid can flow back to product tank 110 (i.e., through supply line 404 and recirculation line 406, because on / off valve 410 is open), and when restriction 414 is relatively closed, the pressure at nozzles 206 can be maintained lower than the limit pressure at which nozzles 206 operate to dispense liquid. That is, if the pressure at nozzles 206 is relatively low because restriction 414 is relatively closed, nozzles 206 may not dispense liquid in the field and instead the liquid flows through recirculation line 406 back to product tank 110. This recirculation mode can be used to discharge or prepare liquid throughout the liquid dispensing system 204, removing air bubbles and diluting any residual liquid used in previous operations.When restriction 414 is relatively open, the liquid distribution system 204 can be ready to dispense liquid from nozzles 206 without delay (due to an increase in pressure at nozzles 206) and without fluctuations in flow that can be caused by air bubbles in the supply line 404.

[050] The on / off valve 410, if present, can serve to prevent backflow to the product tank 110 when the on / off valve 410 is closed.

[051] In certain embodiments, an air supply line 418 may be connected to the supply line 404, such as between the restriction 414 and the manifold 416, as shown in FIG. 4, or between the pump 402 and the restriction. Petition 870250088304, dated 09 / 29 / 2025, pp. 116 / 140 17 / 22 414. When a spraying operation is complete, the air supply line 418 can be connected to a pressurized air source (e.g., a compressor), which can be used to purge the liquid dispensing system 204 of liquid, directing the liquid back to the product tank 110 or out of the nozzles 206. The recirculation line 406 can be purged by opening the on / off valve 410. A check valve 420 or reservoir valve prevents backflow directly to the product tank 110. To limit or prevent flow through the nozzles 206 during such purging, the pressure in the nozzles 206 can be maintained below the limit pressure at which the nozzles 206 operate to dispense liquid, as discussed above.

[052] An operator can control the liquid distribution system 204 via a control environment 422 in the operator cab 106 (FIG. 1) or in an associated vehicle (e.g., the tractor 308 in FIG. 3). The control environment 422 may include, for example, a switch 424 to open and close the on / off valve 410 and the restriction 414, and a display 426 to provide feedback to the operator. In some embodiments, the switch 424 may be a rocker switch that includes one or more indicators, such as a light 428a to indicate that the liquid distribution system 204 is set for recirculation (i.e., the on / off valve 410 is open and the restriction 414 is restricted) and a light 428b to indicate the flow as detected by the flow indicator 412. Although depicted as a single switch 424, multiple switches may control the on / off valve 410 and the restriction 414 separately.Restriction 414 can be controlled by a restriction control signal 430 sent from control environment 422. Control environment 422 can receive a flow indicator signal 432 from flow indicator 412 and can provide, for example, a historical graph and / or an instantaneous reading of the flow through the recirculation line 406. The operator can use such. Petition 870250088304, dated 09 / 29 / 2025, pp. 117 / 140 18 / 22 information to determine if liquid distribution system 204 is operating as expected. It was found that direct measurement of flow in liquid distribution system 204 is more useful as an indicator of proper operation than a pressure measurement in supply line 404, nozzles 206, or elsewhere in liquid distribution system 204, because a system can be pressurized even without flow.

[053] In some embodiments, the control environment 422 can be integrated into an existing machine system as software. The control environment 422 may optionally include warning lights, sounds, or other indicators. The control environment 422 can communicate with the liquid dispensing system 204 via a wired or wireless interface. The control environment 422 can also communicate with another device (e.g., a mobile phone, a tablet, the internet, etc.) via a wired or wireless interface, for monitoring and / or control of the liquid dispensing system 204.

[054] The liquid distribution system 204 shown in FIG. 4 includes a pressure sensor 434 and, optionally, a boom pressure sensor 436. In normal operation (i.e., spraying liquid through the nozzles 206 onto the boom 112), the pressure sensor 434 and / or the boom pressure sensor 436 provide pump pressure signals 438, 440 to the control environment 422 corresponding to the pressure in the supply line 404 and / or on the boom 112.

[055] Control environment 422 may include a control routine to shut down pump 402 operation when pressure sensor 434 and / or 436 detects a low-pressure condition. This routine is used to prevent damage to pump 402 due to operation without fluid (e.g., overheating). For example, in some systems, the control environment may shut down the pump after 10 seconds of low-pressure detection. Such Petition 870250088304, dated 09 / 29 / 2025, pp. 118 / 140 19 / 22 The control routine can prevent fluid recirculation in the liquid distribution system 204 shown in FIG. 4 because, in recirculation mode, the pressure in the supply line 404 and in the nozzles 206 is lower than the pressure required to dispense liquid through the nozzles 206 (and may be lower than the limit at which pump 402 is switched off).

[056] To overcome this condition, the liquid distribution system 204 may include a pressure sensor simulator 442 that can provide a pressure signal 444 to the control environment 422 corresponding to a simulated liquid pressure when the liquid distribution system 204 is in recirculation mode. When the operator initiates a recirculation operation, the pressure sensor simulator 442 can intercept the pump pressure signal 438 from the physical pressure sensor 434, providing instead a signal simulating a pre-selected liquid pressure (e.g., a pressure above the limit at which the pump 402 shuts off).

[057] The pressure sensor simulator 442 is represented in line with the pressure sensor 434 (i.e., the pressure signal 444 from the pressure sensor simulator 442 replacing the signal from the pressure sensor 434 supplied to the control environment 422 as the pump pressure signal 438), but the pressure sensor simulator 442 can alternatively be configured to replace the boom pressure signal 440 from the boom pressure sensor 436. In other embodiments, multiple pressure sensor simulators 442 may be present, such as one in the position shown in FIG. 4 and another in line with the boom pressure sensor 436.

[058] The flow indicator signal 432 can be used by the control environment 422 to confirm that the recirculation mode is operating properly when the pump pressure signals 438, 440 at the pressure sensors 434, 436 are ignored by the simulated pressure from the simulator. Petition 870250088304, dated 09 / 29 / 2025, pp. 119 / 140 20 / 22 pressure sensor 442. Thus, to avoid damage to pump 402, the control environment 422 can confirm that the liquid is actually recirculating when the liquid distribution system 204 is in recirculation mode.

[059] The pressure sensor simulator 442 may be in the form of an electrical harness or other electrical connection. For example, FIG. 7A illustrates an electrical circuit diagram of a pressure sensor simulator 442. The pressure sensor simulator 442 is typically powered by a machine electrical source 702 (e.g., a 5 V source supplied when the crop sprayer 102 is switched on). Current from the electrical source 702 passes through resistors 704, 706 to ground 708. The simulated pressure signal 716 corresponds to a simulated liquid pressure and originates between resistors 704, 706. As is known in the state of the art, the magnitude (voltage) of the simulated pressure signal 716 depends on the magnitude of the electrical source 702 and the relative resistance values ​​of resistors 704, 706 (i.e., by Ohm's Law).

[060] When a recirculation signal 710 is received (for example, a signal from the control environment 422 or elsewhere to indicate that the liquid distribution system 204 is in recirculation mode), current flows through an inductor 712 to ground 708. If there is current flowing through the inductor 712, it determines the position of a switch 714, which can switch between the pump pressure signal 438 and a simulated pressure signal 716. In the position shown in FIG. 7A (i.e., no current flowing through the inductor 712, meaning that the recirculation mode is off), the pressure signal 444 transmitted to the control environment 422 is the pump pressure signal 438 from the pressure sensor 434 (FIG. 4).

[061] FIG. 7B illustrates an electrical circuit diagram in which the switch 714 is switched from the position shown in FIG. 7A. That is, as the Petition 870250088304, dated 09 / 29 / 2025, pages 120 / 140 21 / 22 current is flowing through inductor 712 (because recirculation mode is activated), the pressure signal 444 transmitted to the control environment 422 is the simulated pressure signal 716 from pressure sensor 434 (FIG. 4). Technicians in the field will recognize that the pressure sensor simulator 442 can be configured in other ways to achieve the same result, and that the position and design of inductor 712 and / or switch 714 may vary.

[062] FIG. 8 is a simplified flowchart illustrating a method 800 of operating the crop sprayer 102 (FIG. 1) or the crop sprayer 302 (FIG. 3) in an agricultural field.

[063] In block 802, a signal corresponding to a simulated liquid pressure is provided to the control environment. The signal typically starts when the crop sprayer is switched to recirculation mode.

[064] In block 804, the method involves pumping liquid through the pump, the restriction, at least one of the nozzles, and the recirculation line to the product tank without spraying the liquid from at least one of the nozzles while the control environment receives the signal corresponding to the simulated liquid pressure. The simulated liquid pressure prevents the control environment from shutting down the pump due to low pressure.

[065] In block 806, the restriction is adjusted to decrease a pressure drop associated with the restriction. This typically corresponds to switching the crop sprayer from recirculation mode to spray mode.

[066] In block 808, a signal corresponding to the actual pump pressure is provided to the control environment. The control environment uses the actual pump pressure to ensure that liquid is flowing, which is important if the pump is cooled by the flowing liquid. That is, operating the pump when there is no liquid present can damage the pump. The control environment can shut down the pump if the actual pressure drops. Petition 870250088304, dated 09 / 29 / 2025, pp. 121 / 140 22 / 22

[067] In block 810, liquid is pumped through the pump, restriction and nozzle(s) to spray the liquid from the nozzle(s) while the control environment receives the signal corresponding to the actual pump pressure. The liquid is typically sprayed when the lance bearing the nozzles is propelled (e.g., pulled or ported) across an agricultural field.

[068] The method can be repeated to switch between recirculation mode and spray mode, as desired.

[069] Although represented as a flowchart, some actions in FIG. 8 can be performed simultaneously and, in some modes, some actions can be omitted.

[070] All references cited in the present invention are incorporated into the present invention in their entirety. If there is a conflict between the definitions contained in the present invention and an incorporated reference, the definition in the present invention shall prevail.

[071] Although the present disclosure has been described in the present invention with respect to certain illustrated embodiments, those skilled in the art will recognize and appreciate that it is not so limited. Instead, many additions, deletions, and modifications to the illustrated embodiments can be made without departing from the scope of the disclosure as claimed below, including legal equivalents thereof. Furthermore, the attributes of one embodiment can be combined with attributes of another embodiment while still being encompassed within the scope as contemplated by the inventors. Additionally, the embodiments of the disclosure are useful with different and various types and configurations of machines. Petition 870250088304, dated 09 / 29 / 2025, pp. 122 / 140

Claims

1 / 5 CLAIMS 1. A liquid distribution system for a crop sprayer, characterized in that it comprises: a product tank configured to contain a liquid; a pump in fluid communication with the product tank; at least one nozzle borne by a lance and configured to receive liquid from the pump through a supply line; a recirculation line connecting at least one nozzle to the product tank, the recirculation line comprising an adjustable restriction; a pressure sensor configured to measure a liquid pressure in the supply line; a control environment configured to control the pump; and a pressure sensor simulator configured to provide a signal to the control environment corresponding to a simulated liquid pressure when the liquid distribution system is in recirculation mode;where the restriction is configured to vary the liquid pressure at at least one nozzle when the liquid distribution system is in recirculation mode.

2. Liquid distribution system, according to claim 1, characterized in that the pressure sensor simulator comprises a voltage divider circuit.

3. Liquid distribution system, according to claim 1, characterized in that the pressure sensor simulator comprises an electrical harness.

4. Liquid distribution system, according to claim 1, characterized in that the pressure sensor simulator comprises a switch configured to switch an output from the pressure sensor simulator between a real pump pressure signal and a simulated pressure signal.

5. Liquid distribution system, according to claim 4, characterized in that the switch is controlled by activating the recirculation mode.

6. Liquid distribution system, according to claim 1, characterized in that it further comprises a check valve in the recirculation line, wherein the check valve is configured to prevent flow from the product tank to at least one nozzle through the recirculation line.

7. Liquid distribution system, according to any one of claims 1 to 6, characterized in that it further comprises a flow indicator configured to detect flow through the recirculation line.

8. Liquid distribution system, according to any one of claims 1 to 7, characterized in that at least one nozzle comprises a first plurality of nozzles and a second plurality of nozzles, and wherein each plurality of nozzles is configured to receive the liquid from the pump independently of the other plurality of nozzles.

9. Liquid distribution system, according to claim 8, characterized in that it further comprises a collector configured to receive the liquid from the pump and distribute the liquid to each of the first plurality of nozzles and the second plurality of nozzles.

10. Liquid distribution system, according to any one of claims 1 to 9, characterized in that at least one nozzle comprises a check valve to enable flow through the nozzle when a pressure in at least one nozzle exceeds a limit.

11. Liquid distribution system, according to any one of claims 1 to 10, characterized in that it further comprises a control system configured to control the restriction, wherein, when the restriction is in a first position, the restriction is configured to have a first pressure drop, and wherein, when the restriction is in a second position, the restriction is configured to have a second pressure drop greater than the first pressure drop.

12. Crop sprayer, characterized in that it comprises: a chassis; and the liquid distribution system defined in any one of claims 1 to 11, carried by the chassis.

13. Crop sprayer, according to claim 12, characterized in that it further comprises a chassis-supported engine, the engine configured to propel the chassis through an agricultural field.

14. Crop sprayer, according to claim 12 or 13, characterized in that it further comprises an operator's cab supported by the chassis.

15. Crop sprayer, according to claim 12, characterized in that it further comprises a hitch configured to couple the chassis to a tractor.

16. Method of operation of a crop sprayer, characterized in that it comprises a product tank, a pump, a restriction, a plurality of nozzles spaced along a lance, a recirculation line and a control environment, the method comprising: providing a signal corresponding to a simulated liquid pressure for Petition 870250088304, dated 09 / 29 / 2025, page.138 / 140 4 / 5 the control environment; pump liquid through the pump, the restriction, at least one of the nozzles and the recirculation line to the product tank without spraying the liquid from at least one of the nozzles while the control environment receives the signal corresponding to the simulated liquid pressure; adjust the restriction to decrease a pressure drop associated with the restriction; provide a signal corresponding to a real pump pressure to the control environment; pump the liquid through the pump, the restriction and at least one of the nozzles to spray the liquid from at least one of the nozzles while the control environment receives the signal corresponding to the real pump pressure.

17. A method according to claim 16, characterized in that the plurality of nozzles is configured to spray only when the liquid is above a limit pressure, and in that pumping liquid through the pump, restriction, nozzles and recirculation line to the product tank without spraying the liquid from the plurality of nozzles comprises maintaining a pressure in the nozzles below the limit pressure.

18. A method according to claim 16 or 17, characterized in that pumping the liquid through the pump, the restriction and at least one of the nozzles to spray the liquid from at least one of the nozzles comprises dispensing liquid from at least one of the nozzles while propelling the lance through an agricultural field.

19. Liquid distribution system of a crop sprayer, characterized in that it comprises: a product tank configured to contain a liquid; a pump in fluid communication with the product tank; Petition 870250088304, dated 09 / 29 / 2025, p.139 / 140 5 / 5 at least one nozzle carried by a lance and configured to receive liquid from the pump; a pressure sensor configured to measure the liquid pressure transmitted to the lance by the pump; and a control environment configured to control the pump; the improvement comprising: a recirculation line connecting the at least one nozzle to the product tank; an adjustable restriction configured to pass liquid from the pump to the at least one nozzle, wherein the restriction is configured to vary a liquid pressure in the at least one nozzle when the liquid dispensing system is in a recirculation mode; and a pressure sensor simulator configured to provide a simulated liquid pressure to the control environment when the liquid dispensing system is in recirculation mode.

20. Product, process, system, kit, means or use, characterized in that it comprises one or more elements described in the descriptive report, claims, drawings, sequence listing, or summary of this application, when applicable. Petition 870250088304, dated 09 / 29 / 2025, pp. 140 / 140

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