A PWM variable boom sprayer

Abstract

The present invention provides a PWM variable-speed boom sprayer, comprising a PWM spray control system, a drug supply system, a power system, and a travel assembly, wherein the PWM spray control system, drug supply system, and power system are mounted on the travel assembly. The PWM spray control system comprises a controller, a data acquisition system, a boom mechanism, and a solenoid valve nozzle, wherein the controller is mounted on a frame and connected to the data acquisition system, the boom mechanism, and the solenoid valve nozzle. The data acquisition system collects signals from all sensors and transmits them to a computer via a CAN bus. The computer generates feedback signals based on information such as the set per-acre spray rate. Simultaneously, the controller controls the PWM spray module via electrical signals based on the computer feedback information, precisely controlling the spraying process. The present invention enables real-time evaluation of the spraying quality of the PWM variable-speed sprayer, real-time parameter matching, and optimized adjustment, enabling diversified combinations for different planting environments and crops.

Description

Technical Field

[0001] The present invention relates to the field of agricultural plant protection machinery, and in particular to a PWM variable spray boom sprayer. Background Art

[0002] As a major agricultural country, my country urgently needs to improve its agricultural mechanization and precision agriculture technologies. Crop pest control faces serious problems such as low pesticide utilization, high pesticide residues, severe environmental pollution, and operator poisoning. Currently, variable spray control systems primarily include pressure regulation, concentration regulation, and PWM intermittent spray flow regulation. Pressure regulation has a narrow flow adjustment range and is prone to distortion of spray characteristics; concentration regulation has a long system response time and cannot meet the needs of real-time variable control. PWM intermittent spray flow regulation offers a fast system response, a wide flow adjustment range, and the ability to achieve wide-ranging flow control using standard nozzles without changing droplet size or spray pattern. Therefore, it has become the current development direction of variable spray technology.

[0003] However, ordinary variable boom sprayers cannot fully utilize the advantages of PWM intermittent spray flow regulation. In actual use, there are still cases of uneven spraying and waste of pesticides during use.

[0004] At the same time, the nozzles of ordinary spraying systems adopt a fixed direction structure. During the entire spraying process, the direction of the nozzles remains unchanged, which makes it difficult to achieve full stability when spraying tall plants. Figure 1 As shown in , when the nozzle direction is fixed, there is always a blind spot during the spraying process. The existence of the blind spot affects the spraying uniformity, and the prevention and control of pests and diseases is not thorough, which makes the pests easy to recur. Summary of the Invention

[0005] In view of the problem that existing variable boom sprayers cannot fully exert the PWM intermittent spray flow regulation function, the present invention provides a PWM variable boom sprayer that monitors and regulates pesticide spraying in real time through a data acquisition system.

[0006] The invention provides a PWM variable spray boom sprayer, comprising a PWM spray control system, a medicine supply system, a power system and a traveling assembly, wherein the PWM spray control system, the medicine supply system and the power system are mounted on the traveling assembly.

[0007] The PWM spraying control system includes a controller, a data acquisition system, a spray boom mechanism and a solenoid valve nozzle, wherein the controller is installed on the frame, and the controller is connected to the data acquisition system, the spray boom mechanism and the solenoid valve nozzle. The data acquisition system includes a drug dosage sensor, a system pressure sensor, an overflow device, a total flow sensor and a vehicle speed sensor. The spray boom mechanism is installed at the front end of the walking assembly. The spray boom mechanism includes a lifting mechanism and a spray boom frame. The lifting mechanism includes a parallel four-link lifting frame and a driving push rod. One end of the lifting frame is hinged to the frame, and the spray boom frame is fixed to the other end of the lifting frame. The spray boom water pipe is fixed on the spray boom frame, and a solenoid valve nozzle is provided on the spray boom water pipe. The controller, the data acquisition system and the solenoid valve nozzle are connected by wires; the medicine supply system includes a medicine box and a plunger pump, and the medicine box and the plunger pump are fixed on the frame. The water inlet of the plunger pump is connected to the medicine box, and its water outlet is connected to the spray boom water pipe.

[0008] In order to further facilitate the adjustment of the spraying width, the spray boom includes a middle spray boom and a side spray boom. The middle spray boom is fixed on the movable end of the lifting frame, the side spray booms are arranged on both sides of the middle spray boom, and the spray boom water pipes are fixed on the side spray boom and the middle spray boom.

[0009] Furthermore, the system also includes a prescription spraying system that performs variable-rate spraying according to a prescription map. The system obtains a prescription map for the spray plot and inputs the map information into a controller, which then instructs the sprayer to precisely spray according to the map information. The system also performs variable-rate spraying according to the prescription map, adjusting the duty cycle of the solenoid valve based on the machine's forward speed.

[0010] Furthermore, it also includes a four-axis rotor drone, the image recognition system is set on the four-axis rotor drone, and the four-axis rotor drone and the image recognition system are connected to the controller through a wireless transmission system.

[0011] In order to further improve the comprehensiveness of spraying, the upper support rod in the parallel four-link lifting frame adopts a sleeve rod structure. The upper support rod includes a sleeve and a core rod. The sleeve is hinged on the walking assembly, and the core rod is hinged on the nozzle frame. The core rod is sleeved in the sleeve, the tail end of the driving push rod is hinged on the side panel, and the telescopic end of the driving push rod is hinged on the core rod.

[0012] Furthermore, a screw hole is provided on the sleeve, a bolt is inserted into the screw hole, an arc-shaped sliding hole is provided on the side plate, the bolt passes through the arc-shaped sliding hole and is inserted into the screw hole of the sleeve, the positioning side plate is fixed on the walking assembly, and the bolt slides in the arc-shaped sliding hole.

[0013] In order to solve the spraying problem during the field turning process, the PWM variable boom sprayer of the present invention further includes a field turning compensation system.

[0014] Beneficial effects of the present invention:

[0015] The present invention uses the pesticide dosage sensor, system pressure sensor, overflow device, total flow sensor, vehicle speed sensor, solenoid valve, control panel, etc. in the data acquisition system. The data acquisition system collects signals from all sensors and transmits them to the computer through the CAN bus. The computer sends a feedback signal based on the set per mu spraying amount and other information. At the same time, the controller controls the PWM spraying module through electrical signals according to the information fed back by the computer, accurately controls the spraying process, improves the efficiency of pesticide spraying and the utilization rate of pesticides, reduces the total amount of pesticides used, reduces pesticide residues and improves the spraying effect.

[0016] At the same time, the present invention changes the spray volume by changing the duty cycle. Compared with the traditional method of changing the pressure or concentration to change the spray volume, it has the following great advantages: no change in the constant pressure variable of the pipeline pressure, a wide variable range, more uniform droplet size, high real-time performance, single nozzle control, strong scalability and convenient modification.

[0017] The present invention can evaluate the application quality of PWM variable spray in real time, match parameters in real time, optimize and adjust, and realize diversified combinations for different planting environments and different crops. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0019] Figure 2 It is a schematic diagram of the top structure of the present invention.

[0020] Figure 3 It is a three-dimensional structural schematic diagram of the spray bar mechanism of the present invention.

[0021] Figure 4 These are diagrams of various states of spraying tall plants.

[0022] Figure 5 It is a schematic diagram of the cross-sectional structure of a parallel four-link lifting frame.

[0023] Figure 6 It is a schematic diagram of the motion state of the parallel four-link lifting frame.

[0024] Figure 7 It is the flow chart of PWM variable spray control.

[0025] Figure 8 It is a prescription operation flow chart.

[0026] Figure 9 This is a schematic diagram of the operation of the headland turning compensation system.

[0027] Numbers in the figure: frame 1, front moving wheel 101, rear moving wheel 102, steering control mechanism 103, spray rod mechanism 2, medicine box 3, carrier plate 201, side plate 202, parallel four-link 203, synchronous link 210, drive push rod 204, middle spray rod 205, connecting seat 209, side spray rod 206, spray rod water pipe 207, solenoid valve nozzle 208, sleeve 231, core rod 232, screw hole 233, bolt 234, arc-shaped sliding hole 235. DETAILED DESCRIPTION

[0028] The present invention will be further described below with reference to the accompanying drawings and examples.

[0029] Example 1: To address the serious problems of low pesticide utilization, large residual amounts, severe environmental pollution, and operator poisoning in crop disease and insect pest control, precise pesticide spraying is achieved, reducing pesticide usage while achieving uniform application, and fully utilizing the efficacy of the pesticide. The present invention provides a PWM variable boom sprayer, comprising a PWM spray control system, a drug supply system, a power system, and a travel assembly. The travel assembly and power system can be implemented using conventional agricultural tractors or agricultural crawler vehicles, or customized equipment.

[0030] The traveling assembly comprises at least a frame 1, a front moving wheel 101 and a rear moving wheel 102 are provided at the bottom of the frame 1, wherein the front moving wheel 101 is provided with a steering control mechanism 103, and the rear moving wheel 102 is provided with a power system, which includes a drive motor and a battery.

[0031] A PWM spray control system is mounted at the front of the frame 1, and a pesticide supply system is mounted above the frame 1. The PWM spray control system includes a controller, a data acquisition system, a spray boom mechanism 2, and a solenoid valve nozzle 208. The pesticide supply system includes a medicine box 3 and a plunger pump. Because there are many types of pesticides, some of which need to be mixed, multiple medicine boxes 3 can be provided. The present invention provides two medicine boxes 3.

[0032] The working status parameters of the PWM variable spray boom sprayer include current pressure, current flow, current flow rate, remaining medicine amount, operating speed, etc. The data acquisition system includes at least a medicine amount sensor, a system pressure sensor, an overflow device, a total flow sensor, a vehicle speed sensor, a solenoid valve, a control panel, etc. The data acquisition system collects and summarizes the signals of all sensors and transmits them to the computer through the CAN bus. The computer sends a feedback signal based on the set per mu spray amount and other information. At the same time, the controller controls the PWM spraying module through electrical signals based on the information fed back by the computer.

[0033] The spray boom mechanism 2 includes a carrier plate 201 with a width comparable to that of the frame 1. Corresponding screw holes 233 are provided on the carrier plate 201 and the front end of the frame 1. The carrier plate 201 can be fixed to the front end of the frame 1 by bolts 234. A set of parallel side panels 202 are installed at both ends of the carrier plate 201. A parallelogram 203 is hinged on the side panels 202. The parallelogram 203 at both ends is connected by a synchronization link 210 to ensure the synchronization of the parallelogram 203.

[0034] The side plate 202 is provided with a mounting seat, through which a driving push rod 204 is hinged. The telescopic end of the driving push rod 204 is hinged on the upper support rod of the parallelogram linkage 203, specifically on the synchronous link 210 between the upper side supports of the parallelogram linkage 203.

[0035] A middle spray rod 205 is fixed to the movable end of the parallel four-link 203, and connecting seats 209 are provided at both ends of the middle spray rod 205. Side spray rods 206 are installed through the connecting seats 209. Spray rod water pipes 207 are installed on the middle spray rod 205 and the side spray rods 206. A solenoid valve nozzle 208 is installed on the spray rod water pipe 207 and is connected to the solenoid valve nozzle 208. The spray rod water pipe 207 is connected to the medicine box 3 through a conduit.

[0036] The water inlet of the plunger pump of the medicine supply system is connected to the medicine box 3, and the water outlet of the plunger pump is connected to the three-way valve and is connected to the spray rod water pipe 207 through the three-way valve.

[0037] Specific implementation method: Before spraying, create a new operation project on the control panel, enter the operation name, set the nozzle type, number of nozzles, nozzle spacing, per mu spraying volume and other parameters. The PWM variable spray boom sprayer controller collects parameters such as the dosage sensor, system pressure sensor, overflow device, total flow sensor, vehicle speed sensor, etc., and sends a feedback signal in combination with the set per mu spraying volume and other parameters. At the same time, the controller controls the PWM spraying module through electrical signals based on the information fed back by the computer. During operation, real-time information such as the operating area, operating speed, real-time flow, and real-time pressure are displayed on the control panel.

[0038] Example 2: In order to achieve the change of the direction of the nozzle, the present invention further provides a parallelogram linkage 203, wherein the upper support rod of the parallelogram linkage 203 adopts a sleeve rod structure, the upper support rod includes a sleeve 231 and a core rod 232, the sleeve 231 is hinged on the walking assembly, the core rod 232 is hinged on the nozzle frame, and the core rod 232 is sleeved in the sleeve 231. A driving push rod 204 is installed in the parallelogram linkage 203, and the tail end of the driving push rod 204 is hinged on the side plate 202, and the telescopic end of the driving push rod 204 is hinged on the core rod 232. During the extension and retraction of the driving push rod 204, the four-link linkage is deformed, and at the same time, the core rod 232 moves in the sleeve 231 as the driving push rod 204 retracts and retracts. As the core rod 232 moves, the total length of the upper support rod changes, and the length of the lower support rod remains constant, thereby changing the direction of the nozzle installed on the nozzle frame to achieve all-round spraying and application.

[0039] Specifically, during the process of spraying pesticides, the controller controls the driving push rod 204 to cyclically extend and retract, thereby continuously changing the direction of the nozzle during the spraying process. Before passing the plant, the driving push rod 204 contracts, the nozzle of the nozzle faces forward, and the front side of the plant is sprayed. When passing the plant, the driving push rod 204 is gradually pushed out, and the nozzle rotates toward the frame 1. After passing the plant, the driving push rod 204 continues to extend, and the nozzle further rotates toward the frame 1, and the nozzle faces inward to spray the back of the plant. This spraying method is mainly used for crops with larger plants.

[0040] At the same time, a screw hole 233 is provided on the sleeve 231, and a bolt 234 is inserted into the screw hole 233. The core rod 232 can be locked by the bolt 234. An arc-shaped sliding hole 235 is provided on the side plate 202. The bolt 234 passes through the arc-shaped sliding hole 235 and is inserted into the screw hole 233 of the sleeve 231. The positioning side plate 202 is fixed to the walking assembly. When the bolt 234 is locked, the sleeve 231 and the core rod 232 are locked. The bolt 234 can always slide in the arc-shaped sliding hole 235. When the sleeve 231 and the core rod 232 are locked, the direction of the nozzle is fixed, which is suitable for spraying medicine on small plants.

[0041] There are multiple screw holes 233. By changing the length of the upper support rod through the screw holes 233, the direction of the spray head can be changed and fixed, thereby achieving directional spraying of pesticides on plants.

[0042] Example 3: Furthermore, the present invention also includes a four-axis rotor drone, and a camera is installed on the drone. The drone collects data information of the sprayed plot and transmits it to the controller through a wireless transmission system. The wireless transmission system can use WiFi transmission or 5G transmission.

[0043] Example 4: A further new trend in modern field production: prescription farming. This involves conducting a detailed survey of farmland conditions, establishing detailed prescription maps for information such as pests and diseases, and plant height, and integrating modern information technology (GPS, GIS, RS) with intelligent agricultural machinery to implement a modern agricultural technology system for tailored and precise farmland management.

[0044] The prescription map uses plots as the basic unit to collect various agricultural-related data, including but not limited to: agricultural meteorology, disaster detection, yield forecast, crop growth, planting structure, business entities, arable land plots, administrative divisions, image data, soil fertility and soil classification, etc. By collecting real-space data, a digital space prescription map is produced to form a detailed agricultural digital map.

[0045] The prescription operation is divided into three steps: information collection, quantitative decision-making and variable implementation. The prescription spraying system provided by the present invention is mainly used in the variable implementation stage. The detailed prescription map of the farmland plot is obtained by information collection, and the prescription map information is input into the controller of the PWM variable spray boom sprayer. The corresponding quantitative decision information is set, and the PWM variable spray boom sprayer automatically implements variable precision spraying.

[0046] The PWM variable boom sprayer is equipped with a Beidou positioning device. Through the positioning system and related sensors, it can accurately control the vehicle speed and adjust the real-time flow rate to achieve uniform spraying of pesticides throughout the field.

[0047] Example 6: The PWM variable spray boom sprayer described in the present invention also includes a field turning compensation system. In order to be able to spray quickly and over a large area, the spray boom of a typical sprayer is more than 10 meters long. When the sprayer moves to the field and turns, there is a large difference in the travel length of the inner and outer sides of the spray boom of the sprayer. The movement range of the spray boom on the inside of the turn is small, and the spray repeatability is high. The movement range of the spray boom on the outside of the turn is large, and the spray diffusion degree is high. This leads to uneven spraying inside and outside during the turning process.

[0048] In order to solve this problem, a field turning compensation system is set on the PWM variable spray boom sprayer, which is used to balance the uniformity of pesticide spraying during the turning process.

[0049] The turning compensation function is achieved by the following method: each solenoid valve on the spray boom is controlled independently. When turning, the linear speed of the nozzle on the inside is slow, so the spray duty cycle is reduced accordingly; the duty cycle of the nozzle on the outside is large, so the duty cycle of the solenoid valve is increased accordingly. This ensures that the spray on the inner and outer circles is uniform when turning.

[0050]

[0051] : The flow rate of the i-th nozzle from inside to outside when turning

[0052] i: the i-th nozzle from inside to outside when turning

[0053] v: vehicle speed when turning

[0054] n: Total number of nozzles installed on the spray boom

[0055] Specifically, the PWM variable boom sprayer is equipped with a positioning and navigation system. The plot prescription information is input into the sprayer controller before spraying. At the same time, the controller manually or automatically plans the spray path of the PWM variable boom sprayer, and uses the Beidou navigation system to control the sprayer speed. The controller accurately controls the variable spray according to the prescription map and real-time speed, adjusts the real-time flow rate, and achieves uniform spraying of pesticides throughout the field.

[0056] At the same time, the sprayer's moving position is judged based on the real-time perception of the navigation system and the sensor. When it reaches the end of the field and turns, the controller activates the end of the field turning compensation system, and achieves uniform spraying at the end of the field turning by controlling the flow changes of the inner and outer solenoid valve nozzles.

[0057] The above describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions merely describe the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A PWM variable boom sprayer, characterized in that: It includes PWM spraying control system, drug supply system, power system and walking assembly. The PWM spraying control system, drug supply system and power system are installed on the walking assembly; the PWM spraying control system includes controller, data acquisition system, spray rod mechanism and solenoid valve nozzle, wherein the controller is installed on the frame, the controller is connected to the data acquisition system, spray rod mechanism and solenoid valve nozzle, the data acquisition system includes drug amount sensor, system pressure sensor, overflow device, total flow sensor, vehicle speed sensor and satellite positioning device, the spray rod mechanism ... Installed at the front end of the traveling assembly, the boom mechanism includes a lifting mechanism and a boom frame. The lifting mechanism includes a parallel four-link lifting frame and a driving push rod. One end of the lifting frame is hinged to the frame, and the boom frame is fixed to the other end of the lifting frame. The boom water pipe is fixed to the boom frame, and a solenoid valve nozzle is installed on the boom water pipe. The controller, data acquisition system and solenoid valve nozzle are connected by wires. The medicine supply system includes a medicine box and a plunger pump. The medicine box and plunger pump are fixed to the frame. The water inlet of the plunger pump is connected to the medicine box, and its water outlet is connected to the boom water pipe. It also includes a field turning compensation system and a prescription spraying system. Variable spraying operations are performed according to a prescription map. The prescription map of the spray plot is obtained and the prescription map information is input into the controller. The controller is used to guide the sprayer to spray accurately according to the prescription map information. Variable spraying operations are performed according to the prescription map. The duty cycle of the solenoid valve is adjusted according to the forward speed of the machine to achieve variable spraying. The headland turn compensation system independently controls each solenoid valve nozzle on the spray boom, and the flow rate of each nozzle is calculated using the following formula: ; in, : flow rate of the i-th nozzle from the inside to the outside when turning; i: the i-th nozzle from the inside to the outside when turning; v: vehicle speed when turning; n: total number of nozzles installed on the spray boom; When the sprayer reaches the end of the field and turns, the controller activates the end of the field turning compensation system, which controls the flow changes of the inner and outer solenoid valve nozzles to achieve uniform spraying at the end of the field turning.

2. The PWM variable boom sprayer according to claim 1, characterized in that: The spray rod frame includes a middle spray rod and side spray rods. The middle spray rod is fixed on the movable end of the lifting frame. The side spray rods are arranged on both sides of the middle spray rod. The spray rod water pipes are fixed on the side spray rods and the middle spray rod.

3. The PWM variable boom sprayer according to claim 1, characterized in that: It also includes a four-axis rotor drone, on which the image recognition system is arranged, and the four-axis rotor drone and the image recognition system are connected to a controller via a wireless transmission system.

4. The PWM variable boom sprayer according to claim 1, characterized in that: The upper support rod in the parallel four-link lifting frame adopts a sleeve rod structure. The upper support rod includes a sleeve and a core rod. The sleeve is hinged on the walking assembly, and the core rod is hinged on the nozzle frame. The core rod is sleeved in the sleeve, the tail end of the driving push rod is hinged on the side plate, and the telescopic end of the driving push rod is hinged on the core rod.

5. The PWM variable boom sprayer according to claim 4, characterized in that: The sleeve is provided with a screw hole, and a bolt is set in the screw hole. The side plate is provided with an arc-shaped sliding hole, and the bolt passes through the arc-shaped sliding hole and is set in the screw hole of the sleeve. The positioning side plate is fixed on the walking assembly, and the bolt slides in the arc-shaped sliding hole.

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