CN104170811A - Intelligent low-cost online pesticide mixing device - Google Patents

Abstract

The invention discloses an intelligent low-cost online drug mixing device, which consists of a water tank, a water pump, a water proportional overflow valve, a water flow sensor, a spray pressure sensor, a spray flow sensor, a high-speed switch solenoid valve, a nozzle, a filter, a single Composed of direction valve, unit forward speed Hall sensor, pump input shaft speed sensor, differential pressure sensor, liquid medicine flow regulating valve, liquid medicine proportional overflow valve, liquid medicine injection pump, medicine box and controller. Under the action of the controller, the liquid medicine flow control valve is used to measure and control the medicine flow, combined with various functional modules, the stable control of the medicine flow, water flow, and spray bar pressure can be realized, which can be adjusted online according to the set spray volume and unit forward speed The mixing ratio can be adjusted dynamically according to the change of water flow, so that the concentration of the sprayed liquid can be kept uniform and stable. The medicine mixing device of the invention has high intelligence, low cost and simple structure, can mix pesticides and liquid fertilizers online in real time, and is suitable for constant and variable spraying occasions.

Description

An intelligent low-cost online drug mixing device

technical field

The invention relates to an intelligent low-cost online drug mixing device, which belongs to the field of intelligent agricultural machinery.

Background technique

Compared with the traditional pre-mixing method, the online drug mixing is characterized by the separation of the drug box and the water tank, and online mixing of the drug through the drug mixing device during work. The online drug mixing device can realize the change of pesticide concentration according to the severity of pests and diseases, increase the concentration of pesticide solution in areas with severe pests and diseases, and reduce the concentration of pesticide solution in areas with light pests and diseases, so as to achieve on-demand mixing according to the degree of pests and diseases.

Online drug mixing is currently one of the most effective means to increase the utilization rate of pesticides and reduce environmental pollution, and it is also one of the most effective means to improve the safety of pesticide use. The dynamic detection and stable control of the mixing ratio of the pesticide is the key to ensure the uniform and stable spray concentration of the online mixing device. Considering that the mixing ratio of the pesticide is generally between 1:300 and 1:500 during the operation of the spraying unit, the small amount of pesticide High-precision flow detection is a core problem that must be solved when the online drug mixing device is applied to the actual operation process. In particular, there is no volumetric flowmeter that can detect small flow rates of pesticides on the market. It can detect the flow of pesticides, but high-precision sensors are expensive, so it is necessary to seek low-cost, high-precision measurement methods for pesticides.

In the prior art, the applicant has not found a drug mixing device that can accurately control the drug and water flow online according to the drug mixing ratio (volume ratio or mass ratio of drug and water) and the forward speed of the spray unit. When retrieving existing patents of similar technologies, it was found that Chinese Patent 1 "A Method for Separating Pesticide and Water in a Spray Mechanism" with application number 200510041334.4 discloses a method for separating pesticide and water in a sprayer. The pesticide and water are stored in graduated containers respectively, and the pesticide and water are accurately metered, but the device cannot be automated. Patent 2 (Application No. 200810027898) discloses a "Variable Spray Automatic Mixing Device", which considers the situation that one or more pesticides are sprayed individually or simultaneously, and the spray concentration changes in real time; Patent 3 (Application No. 201010132393.3 ) discloses "An Automatic Mixing Device", which includes a jet part and a spiral part, which is characterized in that the pesticide and water are separated and stored separately, and the automatic, rapid and uniform mixing of the pesticide and water is realized by using the principle of negative pressure and turbulent flow mixing, However, this device cannot achieve accurate metering of medicine and water, and cannot realize precise control of the mixing ratio of medicine and water, and the mixing ratio of medicine and water is directly related to the following important indicators of the effect of pest control in the actual spraying process, and is directly related to the realization of the spray effect , when the actual mixing ratio of the liquid medicine is less than the required mixing ratio, the concentration of the liquid medicine is too small, and the purpose of preventing and controlling pests and diseases cannot be achieved. On the contrary, the concentration of the liquid medicine is too high, which will not only cause damage to the crops, but also cause environmental pollution. Patent 4 (Application No. 201210585002.2) discloses "A Vehicle-mounted Drug Mixing Device", which mainly considers the separate storage of liquid medicine and water and realizes online uniform and rapid mixing, but it still cannot control the mixing ratio of liquid medicine; Patent 5 (Application No. 99228118.0) discloses a "drug mixing device" which utilizes the principle of positive pressure and negative pressure to mix medicine and water. Liquid hole, the pesticide contained in the liquid medicine bag will generate negative pressure when it passes through the constricted part of the medicine mixer during work, and the water injection hole will generate positive pressure. Under the combined action of positive and negative pressure, the pesticide will enter the mixed medicine from the liquid medicine bag The device realizes the mixing of medicine and water. Patent 6 (Application No. 201310670806.7) discloses a "Dynamic Proportion Mixing Device for Plant Protection Machinery Spraying System", which considers the secondary mixing method of medicine and water, that is, the medicine and water are mixed for the first time in the primary mixing box, and then passed The proportional drug mixing pump sucks the primary mixed solution and water into the spraying pipeline for secondary mixing (it is difficult to accurately control the mixing ratio of the drug and water). Patent 7 (the application number is 200920202638.8) discloses a "mechanical peristaltic drug mixing device for sprayer", which drives the crankshaft of the plunger pump and the roller-shaped pressure roller installed on the cam by the same power shaft, so that The flow rate of the plunger pump and the peristaltic tube changes synchronously in an attempt to achieve constant ratio dynamic drug mixing, but this device can only be applied to the situation where the mixing ratio of the drug solution is fixed, and the mixing ratio of the drug solution cannot be changed.

In order to make up for the above shortcomings, the present invention uses a flow regulating valve to measure and control the pesticide flow, and a turbine flowmeter to measure the water flow, and proposes a low-cost intelligent online drug mixing device. The device can automatically and accurately control the flow of medicine and water online according to the mixing ratio and the forward speed of the spray unit, and can adjust the mixing ratio of medicine and water online, so as to adjust the spray concentration online. It has the characteristics of intelligence, low cost, wide application range and convenient installation. .

Contents of the invention

The purpose of the present invention is to provide an intelligent low-cost online drug mixing device to realize automatic online precise control of drug and water flow according to the drug mixing ratio and the forward speed of the spray unit, modify the drug mixing ratio online, change the spray concentration online, and cut costs.

In order to solve the above technical problems, the specific technical scheme adopted in the present invention is as follows:

An intelligent low-cost online drug mixing device, including: water tank (1), water pump (2), water proportional overflow valve (3), water flow sensor (4), spray pressure sensor (5), spray flow sensor (6), high-speed switch solenoid valve (7), nozzle (8) connected to the high-speed switch solenoid valve (7), filter (9), one-way valve (10), unit forward speed Hall sensor (19) , on-board computer (20), tractor power output shaft (17), water pump input shaft speed sensor (18), differential pressure sensor (11), liquid medicine flow regulating valve (12), liquid medicine proportional overflow valve (13), Liquid medicine injection pump (14) and medicine box (15);

The material of the water tank (1) is opaque plastic; the bottom of the water tank and the side wall of the water tank are respectively provided with a water outlet and a water tank return port at a position 15 cm away from the bottom of the water tank, and a water filling port is provided in the center of the top of the water tank; ) is connected to the water pump (2) through the bottom water outlet, and is connected to the water proportional overflow valve (3) through the water tank return port on the side; the water pump (2) is a diaphragm pump, and the liquid inlet of the water pump is connected to the bottom of the water tank through a pipeline connected to the outlet of the water pump; the outlet of the water pump is connected to one end of the water proportional overflow valve (3) through a pipeline, and is connected to the water flow sensor (4) at the same time; the water pump shaft of the water pump (2) is connected to the tractor power output shaft (17 )connect;

Described medicine box (15) adopts opaque plastics to make, medicine box (15) bottom and medicine box (15) side wall are respectively provided with medicine outlet and medicine box at the position of distance medicine box (15) bottom 15cm. The backflow port is provided with a dosing port in the center of the top; the medicine box is connected to the medicine liquid injection pump (14) through the medicine outlet at the bottom, and is connected to the medicine proportional overflow valve (13) through the medicine box backflow port on the side;

One end of the water proportional overflow valve (3) is connected to the medicine tank return port through a pipeline, and the other end is connected to the water pump (2) and the water flow sensor (4); one end of the water flow sensor (4) is connected to the water proportional overflow The valve (3) is connected with the water pump (2), and the other end is connected with the one-way valve (10) and the filter (9);

It is characterized in that it also includes a liquid medicine flow regulating valve (12) and a controller (16); the medicine box (15) is connected with the medicine liquid injection pump (14) through the medicine outlet at the bottom, and is connected with the medicine liquid through the backflow port of the medicine box on the side. The proportional overflow valve (13) is connected; one end of the liquid medicine injection pump (14) is connected with the liquid outlet at the bottom of the medicine tank, and the other end is connected with the medicine proportional overflow valve (13) and the differential pressure sensor (11) at the same time. It is connected with the medicine liquid flow regulating valve (12); one end of the medicine proportional overflow valve (13) is connected with the medicine tank return port through a pipeline, and the other end is connected with the medicine liquid injection pump (14), differential pressure sensor (11) and The liquid medicine flow regulating valve (12) is connected simultaneously;

The liquid medicine flow regulating valve (12) is a needle valve, one end is connected with the liquid medicine injection pump (14), the medicine proportional overflow valve (13) and one end of the differential pressure sensor (11), and the other end is connected with the pressure The regulating valve (21), the one-way valve (10) are connected to the other end of the differential pressure sensor (11); the two ends of the differential pressure sensor (11) are respectively connected to the two ends of the liquid medicine flow regulating valve (12); One end of the one-way valve (10) is connected to the differential pressure sensor (11) and the liquid medicine flow regulating valve (12), and the other end is connected to the water flow sensor (4) and the filter (9) through a pipeline; One end of the electromagnetic valve (7) is connected in series with the nozzle, and the other end is connected to the spraying flow sensor corresponding to the spray bar area;

Described controller (16) is made of controller motherboard (34), PWM assembly A (26), PWM assembly B (27), communication interface (33), man-machine dialogue interface (31), man-machine dialogue device ( 32), solenoid valve drive circuit (24), analog signal output channel (25), vehicle speed detection device (28), pressure flow detection device (30) and power supply (29);

The vehicle speed detection device (28) is composed of a Hall sensor (47), a photoelectric isolation (48), and a pulse shaper (49); the Hall sensor collects the tractor wheel speed information and the diaphragm pump input shaft speed information, and outputs two Pulse signal, the quaternary timer assembly (51) is located in the controller main board (34);

PWM component A (26), PWM component B (27), communication interface (33), man-machine dialogue interface (31) are respectively arranged in the main board of the controller; analog signal output channel (25), vehicle speed detection device (28) , the pressure flow detection device (30) and the power supply (29) are respectively connected with the controller motherboard (34); the man-machine dialogue interface (31) is connected with the man-machine dialogue device (32); the PWM assembly A (26), the PWM assembly B (27) are respectively connected with the solenoid valve drive circuit (24); the pressure flow detection device (30) is made up of I/V conversion circuit (54), pressure sensor (55) and flow sensor (56).

The analog signal output channel (25) is divided into three routes: the first route is the water proportional overflow valve (3) and the liquid medicine proportional overflow valve (13), the integrated electronic unit A (39), the D/A conversion device A (40) and level shifter B (41); the second route consists of liquid medicine flow regulating valve (12), integrated electronic unit B (43), D/A converter B (44), level shifter C (45); the third route consists of liquid medicine injection pump (14), level conversion A (61), D/A converter C (62) and drive circuit (63).

The spray pressure sensor (5) is installed on the main pipeline of the water flow sensor (4) and the common end of the one-way valve (10) sprayer liquid medicine mixture; the filter at one end of the spray flow sensor (6) ( 9) Connect with the spray pressure sensor (5), and connect the other end with the common end of the three solenoid valves in the respective spray bar areas.

The invention detects the water flow by using a water flow meter, monitors and controls the medicine flow through a flow regulating valve, and dynamically adjusts the size of the medicine flow according to the change of the water flow in the operation process, thereby realizing the mixing of different spray concentrations and the same spray concentration. Ratio stability and real-time online adjustment. The analysis of the throttling characteristics of the regulating valve shows that the flow rate Q flowing through the regulating valve is related to the fluid density ρ, the flow coefficient of the regulating valve K _V , the opening degree of the regulating valve O, and the pressure difference between the upstream pressure p ₁ and the downstream pressure p ₂ of the regulating valve Δp is related, that is,

$\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; V</span>}}\mathrm{<span\; class="notranslate">\; N</span>}\sqrt{\frac{{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&rho;</span>}}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; V</span>}}\mathrm{<span\; class="notranslate">\; N</span>}\sqrt{\frac{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}{\mathrm{<span\; class="notranslate">\; \&rho;</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Among them, N is a constant. The flow coefficient K _V changes with the valve opening O. Considering that the volume ratio of the liquid medicine is about 1:300 to 1:500 during the spraying operation, and the proportion of pesticides in the liquid medicine mixture is relatively small, the density of the liquid medicine mixture can be approximated to the density of water, that is, in the mixed liquid During the process, the density of the medicine-water mixture is a constant. Combining formula (1), it can be seen that the pesticide flow rate through the regulating valve is only related to the pressure difference between the upstream and downstream of the flow regulating valve and the valve opening. Therefore, as long as the relationship model between the flow rate and the pressure difference between the upstream and downstream of the flow regulating valve and the valve opening is established through calibration, the actual flow of the liquid medicine can be detected and controlled online by adjusting the valve opening. For the water flow detection, a commercially available turbine flowmeter is used, and the precise control of the mixing ratio of the medicine and water can be realized by precisely controlling the water flow and the medicine flow, so as to realize the precise and stable control of the mixed medicine concentration. .

In the actual operation process, the spray volume needs to be changed according to the forward speed of the spray unit, and the mixing volume of the online medicine mixing device must also change with the change of the spray volume. Considering that the mist volume distribution areas of adjacent nozzles overlap with each other, assuming that the mist volume distribution width of each nozzle is the spray width of the spray unit divided by the number of nozzles, the actual variable spraying operation, each nozzle in the current spraying area The target spray volume is

${\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; 60</span>}\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}\mathrm{<span\; class="notranslate">\; w</span>}}{\mathrm{<span\; class="notranslate">\; 10</span>}\mathrm{<span\; class="notranslate">\; 000</span>}\mathrm{<span\; class="notranslate">\; Cn</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

In the formula, Q ₀ —the target spray volume of the nozzle, L/min; Q _s —the set application amount of the pesticide stock solution of the nozzle in the current spraying area, mL/hm ² ; C—the volume ratio of the spray, mL/L; W—the spraying unit Spray width, m; v—the forward speed of the spray unit, m/s; n—the number of nozzles.

Combined with formula (2), the target amount of pesticide stock solution provided by the flow regulating valve of the mixing device is:

$\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; wxya</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 60</span>}{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}\mathrm{<span\; class="notranslate">\; w</span>}}{\mathrm{<span\; class="notranslate">\; 10</span>}\mathrm{<span\; class="notranslate">\; 000</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

In the formula, Q—the target supply amount of pesticide stock solution, mL/min.

It can be seen from formula (3) that the target amount of pesticide stock solution provided by the flow regulating valve of the mixing device is proportional to Q _s , W, n and v. The opening degree of the regulating valve when the spraying unit is working can be determined by the flow relationship expression of the regulating valve. The mixing ratio can be modified online according to the forward speed of the unit to ensure the continuous stability of the spray concentration during the operation.

The present invention has beneficial effects

(1) In the detection of the pesticide flow, the present invention uses a flow regulating valve to detect and control the flow without using a high-precision flow meter, which reduces the cost. (2) The present invention adjusts the liquid medicine flow rate online and in real time through the dynamic detection of the forward speed and water flow rate of the unit by the controller, so that the medicine mixing device can not only set the medicine mixing ratio online according to the severity of crop diseases and insect pests, but also adjust the speed of the unit according to the progress of the unit. The speed can change the spraying amount and the concentration of the liquid medicine on-line, which greatly improves the degree of intelligence. (3) in the present invention, the spray volume of each nozzle can be changed by controlling the on-off time of the electromagnetic valve connected in series with the shower nozzle by the PWM signal. The duty cycle of the PWM signal is different, and the spray volume is different, so the spray volume and spray volume can be changed online. Mixing concentration, suitable for any large, medium and small spraying units, with a wide range of applications. (4) When calibrating the liquid medicine flow regulating valve, the present invention only needs to install a pressure regulating valve in the downstream pipeline, and the two ends of the pressure regulating valve are connected with the main spraying pipeline through threads. The regulating valve can be removed and replaced with pipes with external threads at both ends to connect. Therefore, the calibration is convenient and no special calibration device is needed.

Description of drawings

Fig. 1 is the structural representation of sprayer mixing device;

Fig. 2 is the calibration schematic diagram of drug mixing device;

Fig. 3 is the structural representation of the controller of this drug mixing device;

Fig. 4 is the controller block diagram of this drug mixing device;

Among them: 1-water tank; 2-water pump; 3-water proportional overflow valve; 4-water flow sensor; 5-spray pressure sensor; 6-spray flow sensor; 7-high-speed switch solenoid valve; 8-nozzle; 9- Filter; 10-one-way valve; 11-differential pressure sensor; 12-medicine liquid flow regulating valve; 13-medicine liquid proportional overflow valve; 14-medicine liquid injection pump; 15-medicine box; 16-controller; 17 -Tractor power output shaft; 18-Water pump input shaft speed sensor; 19-Unit forward speed Hall sensor; 20-On-board computer; 21-Pressure regulating valve; 22-Measuring cylinder; 23-Electronic balance; 24-Solenoid valve drive circuit; 25-analog signal output channel; 26-PWM component A; 27-PWM component B; 28-vehicle speed detection device; 29-power supply; 30-pressure flow detection device; 31-man-machine dialogue interface; 32-man-machine dialogue device; 33-communication interface; 34-controller motherboard; 35-solid state relay; 36-wire driver A; 37-level converter A; 38-general I/O interface A; 39-integrated electronic unit A; 40-D /A converter A; 41-level converter B; 42-SPI serial interface A; 43-integrated electronic unit B; 44-D/A converter B; 45-level converter C; 46-SPI serial Line interface B; 47-Hall sensor; 48-optical isolation; 49-pulse shaper; 50-level converter D; 51-quaternary timer component; 52-A/D converter A; 53-A/ D converter B; 54-I/V conversion circuit; 55-pressure sensor; 56-flow sensor; 57-CAN component; 58-CAN bus transceiver; 59-CAN interface; 60-SPI serial interface C; 61- Level conversion A; 62-D/A converter C; 63-drive circuit; 64-general I/O interface B; 65-level conversion B; 66-line driver B; 67-keyboard and multi-position switch; 68 -External expansion bus; 69-level conversion C; 70-LCD interface.

Detailed ways

The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings.

As shown in Figure 1, the intelligent low-cost online drug mixing device adopted in the present invention mainly includes: water tank 1, water pump 2, water proportional overflow valve 3, water flow sensor 4, spray pressure sensor 5, spraying flow sensor 6, High-speed switching solenoid valve 7, nozzle 8, filter 9, one-way valve 10, differential pressure sensor 11, liquid medicine flow regulating valve 12, liquid medicine proportional overflow valve 13, liquid medicine injection pump 14, medicine box 15, controller 16. Tractor power output shaft 17, water pump input shaft speed sensor 18, unit forward speed Hall sensor 19 and on-board computer 20.

The water tank is made of opaque plastic, the bottom of the water tank and the side wall of the water tank are respectively provided with a water outlet and a water tank return port at a position 15 cm away from the bottom of the water tank, and a water filling port is provided in the center of the top; It is connected to the water pump 2, and on the other hand, it is connected to the water proportional overflow valve 3 through the water tank return port on the side wall. The water pump 2 is a diaphragm pump, the liquid inlet of the water pump is connected to the water outlet at the bottom of the water tank through a pipeline, the liquid outlet of the water pump is connected to one end of the water proportional overflow valve 3 through a pipeline, and is connected to the water flow sensor 4 at the same time; It is connected with the tractor power output shaft of the spraying unit. Driven by the tractor power output shaft, the water enters the pipeline through the water pump to fully and evenly mix with the liquid medicine from the medicine tank; the water pump 2 is driven by the tractor power output shaft. The water is pumped into the pipeline to fully and evenly mix with the medicinal liquid from the medicine box 15 .

The water proportional overflow valve 3 is a DBEE6-1X/50 pilot-operated proportional overflow valve produced by Bosch Rexroth AG, one end of which is connected to the return port of the medicine tank through a pipeline, and the other end is connected to the water pump 2 and the water flow rate at the same time. The sensor 4 is connected for stable control of the spray bar pressure;

The water flow sensor 4 is selected from the LWGY-15 liquid turbine flow sensor produced by Beijing Tianyu Hengchuang Co., Ltd., which is used to measure the flow of water passing through the spray boom. One end of the flow sensor is connected to the water proportional overflow valve 3 and the water pump 4. Connect, the other end is connected with check valve 10 and filter 9;

The medicine box 15 is made of opaque plastic, and the bottom of the medicine box and the side wall of the medicine box are respectively provided with a medicine outlet and a return port at a position 15 cm away from the bottom of the medicine box, and a medicine feeding port is provided at the center of the top; The tank is connected to the liquid medicine injection pump 14 through the medicine outlet at the bottom, and is connected to the medicine proportional overflow valve 13 through the backflow port on the side;

The medicinal liquid injection pump 14 adopts an RS-360SH type gear pump, and one end of the medicinal liquid injection pump 14 is connected with the liquid outlet at the bottom of the medicine tank, and the other end is connected with the medicine proportional overflow valve 13 and the medicine flow regulating valve 12 at the same time. Used to provide power for the flow of medicine in the pipeline;

Described medicine proportional overflow valve 13 selects the DBEE6-1X/50 type pilot type proportional overflow valve produced by German Bosch Rexroth AG, which is connected with the medicine tank return port through one end of the pipeline, and the other end is connected with the medicine liquid injection pump 14 and The drug flow regulating valve 12 is connected at the same time for stable control of the pressure of the drug pipeline;

The liquid medicine flow regulating valve 12 is a needle valve for real-time measurement and control of the liquid medicine flow, one end of which is connected with the liquid medicine injection pump 14, the medicine proportional overflow valve 13 and one end of the differential pressure sensor 11. The other end of the flow regulating valve 12 is simultaneously connected with the other end of the check valve 10 and the differential pressure sensor 11;

The differential pressure sensor 11 is selected from the HM31HM31-3-A1-F0-W1 differential pressure transmitter of the German HELM company, and the two ends of the differential pressure transmitter are respectively connected with the two ends of the liquid medicine flow regulating valve 12 for controlling The differential pressure at both ends of the liquid medicine flow regulating valve 12 is detected;

One end of the one-way valve 10 is connected to the differential pressure sensor 11 and the liquid medicine flow regulating valve 12, and the other end is connected to the water flow sensor 4 and the filter 9 through a pipeline to prevent the liquid medicine mixture from flowing back into the medicine box;

The filter 9 is installed on the main pipeline of the liquid medicine mixture of the sprayer, and is used to filter the liquid medicine mixture;

The spray pressure sensor 5 is selected from the CYT101 pressure transmitter produced by Beijing Tianyu Hengchuang Co., Ltd., and is installed on the main pipeline of the liquid medicine mixture of the sprayer to detect the pressure of the spray bar;

The spray flow sensor 6 is selected from 4 LWGY-6 liquid turbine flow sensors produced by Beijing Tianyu Hengchuang Co., Ltd., which are used to detect the spray flow in each spray bar area. One end of each flow sensor is connected to the filter 9 and the spray The pressure sensor 5 is connected, and the other end is connected to the common end of the three solenoid valves in the respective boom areas;

The solenoid valve 7 is a high-speed switching solenoid valve of the 6013 type direct-acting solenoid valve, one end is connected to the nozzle 8 connected in series, and the other end is connected to the spraying flow sensor 6 corresponding to the spray bar area. Under the action of the controller 16, the high-speed switching The solenoid valve is turned on and off, thereby controlling the working state of the sprinklers connected in series. When the solenoid valve is opened, the liquid medicine mixture is sprayed out from the corresponding nozzle through the solenoid valve; when the solenoid valve is closed, the corresponding nozzle stops working;

The nozzle 8 is selected from the TR80-05 conical mist nozzle produced by the German Lechler company, which is respectively connected to the high-speed switching solenoid valve 7 connected in series.

As shown in Figure 2, the liquid medicine flow calibration system in an intelligent low-cost online medicine mixing device of this invention consists of a differential pressure sensor 11, a liquid medicine flow regulating valve 12, a liquid medicine proportional overflow valve 13, and a medicine liquid injection pump 14. It consists of a medicine box 15, a controller 16, a pressure regulating valve 21, a measuring cylinder 22 and an electronic balance 23. Among them, the connection relationship between the differential pressure sensor 11, the liquid medicine flow regulating valve 12, the liquid medicine proportional overflow valve 13, the liquid medicine injection pump 14, the medicine tank 15, and the controller 16 has been described above and will not be repeated here. . The pressure regulating valve 21 is connected to the outlet pipeline of the flow regulating valve 12 for regulating the pressure difference at both ends of the flow regulating valve 12; the measuring cylinder is placed directly below the liquid medicine outlet pipeline and placed on an electronic balance It is used to collect the amount of medicine flowing out through the flow regulating valve 12, and the electronic level is used to weigh the amount of medicine collected in the measuring cylinder. Using the drug mixing device to realize intelligent online drug mixing includes the following steps:

(1) Calibration of liquid medicine flow regulating valve

1) replace the pesticide with water, set the chemical liquid proportional overflow valve 13 to 0.5MPa, water enters the main pipeline from the chemical tank through the chemical liquid flow regulating valve, manually adjust the pressure regulating valve 21 to change the pressure difference at both ends of the flow regulating valve, Set the pressure difference at both ends of the flow regulating valve to different values.

2) Under each pressure difference condition, the opening of the flow regulating valve is controlled by the controller to gradually decrease from 100% to 10% in steps of 5%. After the spray pressure is stabilized, spray continuously for 60s at each opening At the same time, use a 2000mL graduated cylinder and an electronic balance with an accuracy of ±0.1g to record the volume and mass of water, and calculate the volume flow and mass flow of the liquid medicine under different pressure differences and corresponding openings.

3) Through the above process, the effective sample data under different pressure difference conditions and different opening conditions can be obtained, the sample data is stored in the controller, and the opening degree of the flow regulating valve and the opening degree of the flow regulating valve are obtained by using the nonlinear modeling method. The expression of the relationship between the end pressure difference and the flow through the flow regulating valve, and finally store the coefficient of the expression in the controller.

(2) Application of mixing device

In application, through the required amount of liquid medicine and the pressure difference at both ends of the flow regulating valve obtained online, the control amount-the opening of the valve can be obtained to control the flow of liquid medicine. The pesticide flow through the flow regulating valve can be calculated online by the difference and the valve opening.

As shown in Figure 3, the controller 16 is composed of a controller main board 34, a PWM assembly A26, a PWM assembly B27, a communication interface 33, a man-machine dialogue interface 31, a man-machine dialogue device 32, a solenoid valve driving circuit 24, and an analog signal output channel 25. Vehicle speed detection device 28, pressure flow detection device 30 and power supply 29 form. PWM component A26, PWM component B27, communication interface 33, man-machine dialogue interface 31 are arranged in the controller motherboard; 34; the man-machine dialogue interface 31 is connected to the man-machine dialogue device 32; the PWM component A26 and the PWM component B27 are connected to the solenoid valve drive circuit 24. According to Fig. 3 and shown in Fig. 4, vehicle speed detecting device 28 is made up of Hall sensor 47, photoelectric isolation 48, pulse shaper 49 and level shifter D 50, and Hall sensor 47 gathers tractor drive wheel or water pump speed information, passes The built-in quaternary timer assembly 51 in the controller main board 34 receives the pulse signal and performs pulse frequency measurement. Since the pulse signal output by the Hall sensor 47 is distorted during transmission, in order to make the quaternary timer in the controller main board The component 51 obtains a relatively ideal square wave signal, and the pulse is pre-shaped by the Schmitt trigger SN74LS14; the pressure flow detection device 30 is composed of an I/V conversion circuit 54, a pressure sensor 55 and a flow sensor 56, which are used to control the spray The boom pressure, the total pressure of the spray boom and the pipe pressure of each spray boom section are tested. The analog signal output channel 25 is divided into 3 routes, which are respectively used to control the medicine proportional overflow valve, water proportional overflow valve, flow regulating valve and liquid medicine injection pump. The first route is the proportional overflow valve 3, 13, integrated electronic unit Composed of A39, D/A converter A40, and level converter B41; the second route consists of liquid medicine flow regulating valve 12, integrated electronic unit B43, D/A converter B 44, and level converter C 45; the third route Liquid medicine injection pump 14, level conversion A 61, D/A converter C 62, drive circuit 63 are formed. The communication interface 33 is connected to the CAN bus transceiver 58 ; the man-machine dialogue device 32 includes a keyboard, a multi-position switch 67 and an LCD interface 70 .

As shown in Figure 4, the digital signal controller DSP56F80534 chip integrates PWM component A26, PWM component B 27, communication interface 33, man-machine dialogue interface 31, man-machine dialogue device 32, SPI interfaces 42, 46, 60, general I/O Interface 38, 64, CAN component 57, quad timer component 51, A/D converter 52, 53, external expansion bus 68. The general-purpose I/O interface 38 is connected to the high-speed switching solenoid valve 7 through the level shifter A 37, the line driver 36 and the solid state relay 35 in turn. The pressure sensor 55 and the flow sensor 56 are connected to the A/D converter A 52 and the A/D converter B53 respectively after passing through the I/V level conversion circuit 54 together. The CAN interface 59 is connected to the CAN component 57 through the CAN bus transceiver 58 . LCD interface 70 is connected to external expansion bus 68 through level conversion C 69. The keyboard and the multi-position switch 67 are connected to the general I/O interface B 64 through the line driver B 68 and the level shifter B 65 in turn. Hall sensor 47 is connected to quaternary timer assembly 51 through photoelectric isolation 48, pulse shaper 49, level shifter D 50 in turn. The liquid medicine flow regulating valve 12 is connected to the SPI serial interface B 46 sequentially through the integrated electronic unit B 43 , the D/A converter B 44 , and the level converter C 45 . Proportional relief valves 3 and 13 are connected to SPI serial interface A 42 through integrated electronic unit A 39, D/A converter A 40, and level converter B 41 in sequence.

The unit forward speed Hall sensor is composed of JK8002C Hall proximity switch and 8 magnetic steels installed on the driving wheel hub to detect the speed of the tractor driving wheel, thereby indirectly realizing the measurement of the forward speed of the spray unit .

The working process of the present invention is as follows: through the communication interface 34 or the human-machine dialogue interface 31 of the controller 16, the target spray volume and the mixing ratio are received; Convert it into the forward speed of the unit, calculate the corresponding water flow and drug flow according to the area target spray volume, unit forward speed and drug mixing ratio, collect the pressure difference at both ends of the drug liquid flow regulating valve 12 through the differential pressure sensor 11, and combine the The relational expression of the flow regulating valve 12 can further calculate the valve opening corresponding to the liquid medicine flow regulating valve 12, so that the medicine flow can be adjusted in real time online; The obtained water flow rate adjusts the drug flow rate online to keep the mixing ratio stable, so as to achieve a constant spray concentration. Simultaneously, the spraying flow sensor 6 in each spraying bar partition branch carries out real-time detection to the total spraying flow rate of each spraying bar area, and fine-tunes the duty cycle of the PWM control signal with each spray head electromagnetic valve; Simultaneously The boom pressure is detected in real time. According to the set spray bar pressure, the spray bar pressure is adjusted in real time through the proportional overflow valve to achieve stable control of the spray bar pressure. The controller 16 has two working modes: stand-alone and online. In the stand-alone mode, the operating parameters are manually input or set through the man-machine dialogue device 32. In the online mode, the on-board computer 20 is set through the communication interface 33; the vehicle speed signal is real-time through the vehicle speed detection device 28 get.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. The present invention has been described in detail with reference to the preferred embodiments. Those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications and equivalent replacements, without departing from the spirit and scope of the technical solutions of the present invention, should be covered by the scope of the claims of the present invention.

Claims (3)

1. the online medicament-mixing device of intelligent low cost, comprise: water tank (1), water pump (2), water proportional pressure control valve (3), water flow sensor (4), atomisation pressure sensor (5), spray flow sensor (6), high-speed switch electromagnetic valve (7), be connected in the shower nozzle (8) on high-speed switch electromagnetic valve (7), filter (9), check valve (10), unit pace Hall element (19), car-mounted computer (20), tractor motive power output shaft (17), water pump power shaft rotating speed sensor (18), differential pressure pick-up (11), medicinal liquid flow control valve (12), liquid proportional pressure control valve (13), chemicals feed pump (14) and medicine-chest (15),

Described water tank (1) material is lighttight plastics; On water tank bottom and water tank sidewall, the position of distance water tank bottom 15cm is respectively arranged with delivery port and water tank refluxing opening, and tank top centre is provided with filler; Water tank (1) is connected with water pump (2) by bottom delivery port, is connected by the water tank refluxing opening of side with water proportional pressure control valve (3) simultaneously; Described water pump (2) is membrane pump, and water pump inlet is connected with the delivery port of water tank bottom by pipeline; Water pump liquid outlet is connected with water proportional pressure control valve (3) one end by pipeline, is connected with water flow sensor (4) simultaneously; The pump shaft of water pump (2) is connected with the tractor motive power output shaft (17) of spraying unit;

Described medicine-chest (15) adopts lighttight plastics manufacture, and on medicine-chest (15) bottom and medicine-chest (15) sidewall, the position of distance medicine-chest (15) bottom 15cm is respectively arranged with medicine outlet and medicine-chest refluxing opening, and top centre is provided with dosing mouth; Medicine-chest is connected with chemicals feed pump (14) by bottom medicine outlet, is connected by the medicine-chest refluxing opening of side with medicine proportional pressure control valve (13) simultaneously;

Described water proportional pressure control valve (3) one end is connected with medicine-chest refluxing opening by pipeline, and the other end is connected with water flow sensor (4) with water pump (2); One end of water flow sensor (4) is connected with water proportional pressure control valve (3) and water pump (2), and the other end is connected with check valve (10) and filter (9);

it is characterized in that: also comprise medicinal liquid flow control valve(12) and controller(16); Medicine-chest (15) is connected with chemicals feed pump (14) by bottom medicine outlet, is connected with medicine proportional pressure control valve (13) by the medicine-chest refluxing opening of side; One end of described chemicals feed pump (14) is connected with the liquid outlet of medicine-chest bottom, and the other end is connected with medicine proportional pressure control valve (13), differential pressure pick-up (11) and medicinal liquid flow control valve (12) simultaneously; Described medicine proportional pressure control valve (13) one end is connected with medicine-chest refluxing opening by pipeline, and the other end is connected with chemicals feed pump (14), differential pressure pick-up (11) and medicinal liquid flow control valve (12) simultaneously;

described medicinal liquid flow control valve (12)it is a needle-valve, one end is connected with one end of chemicals feed pump (14), medicine proportional pressure control valve (13) and differential pressure pick-up (11), and the other end is connected with the other end of pressure-regulating valve (21), check valve (10) and differential pressure pick-up (11) simultaneously; Described differential pressure pick-up (11) two ends are connected with the two ends of medicinal liquid flow control valve (12) respectively; One end of described check valve (10) is connected with differential pressure pick-up (11) and medicinal liquid flow control valve (12), and the other end is connected with water flow sensor (4) and filter (9) by pipeline simultaneously; Described magnetic valve (7) one end shower nozzle of connecting, the corresponding spray boom of another termination district sprays flow sensor;

described controller(16) formed by controller motherboard (34), PWM assembly A (26), PWM assembly B (27), communication interface (33), man-machine dialogue interface (31), human-computer dialogue device (32), driving circuit for electromagnetic valve (24), analog signal output passage (25), vehicle speed detector device (28), pressure flow checkout gear (30) and power supply (29);

Described vehicle speed detector device (28) is made up of Hall element (47), photoelectricity isolation (48), pulse shaper (49); Hall element gathers tractor wheels rotary speed information and membrane pump power shaft rotating speed information, output two pulse signals, and quaternary timer assembly (51) is positioned at controller motherboard (34);

PWM assembly A (26), PWM assembly B (27), communication interface (33), man-machine dialogue interface (31) are separately positioned in controller motherboard; Analog signal output passage (25), vehicle speed detector device (28), pressure flow checkout gear (30) and power supply (29) are connected with controller motherboard (34) respectively; Man-machine dialogue interface (31) connects human-computer dialogue device (32); PWM assembly A (26), PWM assembly B (27) are connected with driving circuit for electromagnetic valve (24) respectively; Pressure flow checkout gear (30) is made up of I/V translation circuit (54), pressure sensor (55) and flow sensor (56).

2. the online medicament-mixing device of the intelligent low cost of one according to claim 1, is characterized in that: described analog signal output passage (25) is divided into three tunnels: the first via is made up of with liquid proportional pressure control valve (13), integrated electronic unit A (39), D/A converter A (40) and level translator B (41) water proportional pressure control valve (3); Secondary route medicinal liquid flow control valve (12), integrated electronic unit B (43), D/A converter B (44), level translator C (45) composition; Third Road is made up of chemicals feed pump (14), level conversion A (61), D/A converter C (62) and drive circuit (63).

3. the online medicament-mixing device of the intelligent low cost of one according to claim 1, is characterized in that: described atomisation pressure sensor (5) is arranged on the main pipeline of water flow sensor (4) and check valve (10) common port place sprayer liquid medicine mixed liquor; Described flow sensor (6) one end filter (9) that sprays is connected with atomisation pressure sensor (5), and the other end is connected with the common port of 3 magnetic valves in spray boom district separately.