A method for controlling discharging of a charging car

Abstract

The application discloses a feeding vehicle's discharging control method, the front end of the feeding vehicle is provided with a hopper through an oil cylinder, the oil cylinder is used for lifting the hopper, a push plate which can move forward and backward is arranged in the hopper, a servo electric push rod which is used for pushing the push plate is arranged behind the hopper, and the telescopic end of the servo electric push rod is connected with the push plate; the feeding vehicle is further provided with a hydraulic sensor which is arranged on the oil cylinder and is used for detecting the oil pressure information in the oil cylinder, and a controller which is connected with the hydraulic sensor and the servo electric push rod respectively; the controller is used for calculating the weight of the material in the hopper according to the oil pressure information and controlling the advancing speed of the telescopic end of the servo electric push rod.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engineering charging vehicle control, and particularly relates to a charging vehicle discharging control method. BACKGROUND

[0002] In current industrial production, the charging vehicle often encounters a series of problems caused by the differences in the properties of the materials when performing the material discharging task. Specifically, when the material has a high viscosity, the charging vehicle may encounter the problem of material blockage in the discharging process at the same pushing speed of the push plate, which seriously affects the smoothness of discharging. On the other hand, if the friction coefficient of the material is too low, the discharging speed may become too fast, resulting in uneven discharging speed and thus reducing the production efficiency. In some specific application scenarios, such as concrete mixing, the unevenness of the discharging rate of the charging vehicle when discharging cement, sand, stone aggregate and the like may cause the imbalance of the material proportion, thereby affecting the final strength of the concrete. This is because the excessive fast discharging speed may lead to insufficient mixing, thereby forming clumps or stratification. In addition, when brittle materials are put into a crusher or a mixing device, if the discharging speed is too fast, collisions may occur between the materials, causing the materials to be crushed and generating too much waste, while also increasing the risk of equipment blockage or exacerbating equipment wear. When flammable powder is put into a closed workshop, if the discharging rate is not properly controlled, the excessive fast discharging speed may raise a large amount of dust, which may cause dangerous situations once reaching the explosion limit. SUMMARY

[0003] The purpose of the present application is to solve the above problems and provide a charging vehicle discharging control method.

[0004] The technical solution of the present application is as follows:

[0005] The present application provides a charging vehicle discharging control method, the front end of the charging vehicle is provided with a hopper through an oil cylinder, the oil cylinder is used to lift the hopper, a push plate that can move forward and backward is arranged in the hopper, a servo electric push rod for pushing the push plate is arranged at the rear of the hopper, and the extension end of the servo electric push rod is connected with the push plate; the charging vehicle is further provided with a hydraulic sensor arranged on the oil cylinder, the hydraulic sensor is used to detect the oil pressure information in the oil cylinder; a controller connected with the hydraulic sensor and the servo electric push rod respectively; the controller is used to calculate the weight of the material in the hopper according to the oil pressure information and control the pushing speed of the extension end of the servo electric push rod.

[0006] The control method comprises the following steps:

[0007] S1, the controller controls the oil cylinder to make the hopper in a horizontal position, and obtains load oil pressure information in the oil cylinder through the hydraulic sensor, and the controller further obtains the weight of the material in the hopper according to the difference between the load oil pressure information and no-load oil pressure information, wherein the no-load oil pressure information is the oil pressure information recorded when the hopper is in a horizontal no-load state and the extension end of the servo electric push rod is in an initial position;

[0008] S2, when discharging, the servo electric push rod is controlled to push the push plate to discharge at an initial pushing speed, and the controller further obtains the change information of the load oil pressure in the oil cylinder when the extension end of the servo electric push rod is in different positions in real time through the hydraulic sensor, and further obtains the change amount of the material in the hopper per unit time according to the difference between the change information of the load oil pressure and the change information of the no-load oil pressure, and further obtains the discharging rate per unit time, wherein the change information of the no-load oil pressure is the oil pressure information recorded when the hopper is in a horizontal no-load state and the servo electric push rod is in different positions;

[0009] S3, whether the discharging rate is in a preset range is judged, if yes, the push plate is pushed to discharge at the initial pushing speed, and if not, the initial pushing speed is corrected to control the discharging rate to be in the preset range.

[0010] The advantages or beneficial effects of the above technical solutions at least include:

[0011] The method obtains the dynamic friction coefficient between the material in the hopper and the inner wall of the hopper, the density of the material, the angle of repose, the particle size of the material and the cohesion, and adjusts the pushing speed of the servo electric push rod in real time according to the change of the material characteristics. For the characteristics of different materials, the protection mechanism or the humidity compensation mechanism is triggered. Then, the discharging rate of different materials is recorded and summarized to form a database. The present application realizes accurate discharging control of different characteristic materials, effectively solves the problem that the traditional discharging system is difficult to adapt to the change of material characteristics, improves the discharging precision and efficiency, reduces the abnormal situations such as blockage and uneven discharging, and provides a more reliable and intelligent discharging solution for industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0012] The accompanying drawings illustrate exemplary embodiments of the present application and, together with the general description given above, and explained below, serve to explain the principles of the present application. These drawings are included herein to provide further understanding of the present application and are incorporated in and constitute a part of the specification.

[0013] Figure 1 A schematic view showing the structure of the charging car of the embodiment of the present application is shown;

[0014] Figure 2A position diagram of a servo electric push rod of an embodiment of the present application is shown.

[0015] Figure 3 A position diagram of a servo oil cylinder of an embodiment of the present application is shown.

[0016] Reference signs: 10, charging car; 11, hopper; 111, push plate; 12, servo electric push rod; 13, oil cylinder. DETAILED DESCRIPTION

[0017] Embodiments of the present application will be described in more detail with reference to the drawings. While several embodiments of the present application are shown in the drawings, it is understood that the present application can be embodied in various forms and should not be interpreted in a limited sense as set forth in the embodiments set forth herein, but rather the embodiments are provided to more thoroughly and completely understand the present application. It should be understood that the drawings and embodiments of the present application are for illustrative purposes only and are not intended to limit the scope of protection of the present application.

[0018] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0019] It should be understood that the term "comprising" and its variants as used herein are open and inclusive, i.e., "comprising but not limited to". The term "based on" is "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Related definitions of other terms will be given in the following description. It should be noted that the "first", "second", etc. concepts mentioned in the present application are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0020] It should be noted that the modification of "one" or "multiple" mentioned in the present application is illustrative and not limiting, and those skilled in the art should understand that unless otherwise explicitly indicated in the context, it should be understood as "one or more".

[0021] The names of the messages or information exchanged between the multiple devices in the embodiments of the present application are only for illustrative purposes and do not limit the scope of the messages or information.

[0022] The application discloses a method for controlling discharging of a charging vehicle 10. The front end of the charging vehicle 10 is provided with a hopper 11 through an oil cylinder 13. The oil cylinder 13 is used for lifting the hopper 11. A push plate 111 is arranged in the hopper 11 and can move forward and backward. A servo electric push rod 12 is arranged at the rear of the hopper 11 and is used for pushing the push plate 111. The extension end of the servo electric push rod 12 is connected with the push plate 111. The charging vehicle 10 is further provided with a hydraulic sensor which is arranged on the oil cylinder 13 and is used for detecting the oil pressure information in the oil cylinder 13. A controller is connected with the hydraulic sensor and the servo electric push rod 12 respectively. The controller is used for calculating the weight of the material in the hopper 11 according to the oil pressure information and controlling the pushing speed of the extension end of the servo electric push rod 12.

[0023] The method for controlling discharging comprises the following steps.

[0024] In the step S2, the pushing speed of the servo electric push rod 12 is controlled to push the push plate 111 to discharge at an initial pushing speed. The load oil pressure change information of the oil cylinder 13 at different positions of the extension end of the servo electric push rod 12 is acquired in real time through the hydraulic sensor. The controller is further used for acquiring the change amount of the material in the hopper 11 according to the difference between the load oil pressure change information and the no-load oil pressure change information. The no-load oil pressure change information is the oil pressure information recorded when the hopper 11 is in a horizontal no-load state and the extension end of the servo electric push rod 12 is in an initial position. The discharging speed per unit time is further acquired.

[0025] S1, the controller controls the oil cylinder 13 to make the hopper 11 in a horizontal position. The load oil pressure information in the oil cylinder 13 is acquired through the hydraulic sensor. The controller is further used for acquiring the weight of the material in the hopper 11 according to the difference between the load oil pressure information and the no-load oil pressure information. The no-load oil pressure information is the oil pressure information recorded when the hopper 11 is in a horizontal no-load state and the extension end of the servo electric push rod 12 is in an initial position.

[0026] S2, in the step S2, the pushing speed of the servo electric push rod 12 is controlled to push the push plate 111 to discharge at an initial pushing speed. The load oil pressure change information of the oil cylinder 13 at different positions of the extension end of the servo electric push rod 12 is acquired in real time through the hydraulic sensor. The controller is further used for acquiring the change amount of the material in the hopper 11 according to the difference between the load oil pressure change information and the no-load oil pressure change information. The no-load oil pressure change information is the oil pressure information recorded when the hopper 11 is in a horizontal no-load state and the extension end of the servo electric push rod 12 is in an initial position. The discharging speed per unit time is further acquired.

[0027] S3, the discharging speed is judged whether in a preset range. If yes, the pushing speed of the push plate 111 is controlled to discharge at an initial pushing speed. If not, the initial pushing speed is corrected to control the discharging speed in the preset range.

[0028] Specifically, the material is mostly rock material or granular bulk material. When the material is poured into the hopper 11, it is flat or has a pile, but regardless of the state, when the push plate 111 pushes the material forward, the material will be discharged from the front opening of the hopper 11. The amount of material discharged from the hopper 11 per unit time determines the difference between the load oil pressure change information and the no-load oil pressure change information, and the change amount of the material in the hopper 11 is obtained. This change amount is real-time change, for example, the material uniformly covers the hopper 11, and the top is flat without high peaks and valleys. When discharging, the change amount per unit time is mostly within the threshold range. If the thickness of the material in the length direction of the hopper 11 is large or small, when the push plate 111 is pushed forward, the material at the peak has a larger thickness, and the amount of material falling from the opening per unit time is larger, so the weight change rate of the hopper 11 per unit time will suddenly increase. At this time, the controller reduces the initial pushing speed, and the reduction rate is lower than 5%, and the minimum speed is not lower than 5cm / S, otherwise the material discharge will be discharged too slowly. If the weight change rate of the hopper 11 per unit time returns to the threshold after reduction, the push plate 111 returns to the initial pushing speed to advance.

[0029] Similarly, when the material at the trough has a smaller thickness, the amount of material falling from the opening per unit time is smaller, so the weight change rate of the hopper 11 per unit time will suddenly decrease. At this time, the controller increases the initial pushing speed, and the increase rate is lower than 5%, otherwise the material discharge will be normally performed due to the too fast increase rate. If the weight change rate of the hopper 11 per unit time returns to the threshold after reduction, the push plate 111 returns to the initial pushing speed to advance.

[0030] In step S1, the controller controls the oil cylinder 13 to make the hopper 11 in a horizontal position, and obtains the load oil pressure information in the oil cylinder 13 through the hydraulic sensor. The controller further obtains the weight of the material in the hopper 11 according to the difference between the load oil pressure information and the no-load oil pressure information, specifically comprising:

[0031] S11, when the hopper 11 is in a horizontal no-load state, the load oil pressure information P in the oil cylinder 13 is obtained through the hydraulic sensor （0，0） , and the weight M of the hopper 11 is recorded （0，0） ;

[0032] S12, different weights of loads M （0，1） , M （0，2） ,... M （0，n） are placed on the hopper 11, and the load oil pressure information P （0，1） , P （0，2） ,... P （0，n） in the oil cylinder 13 is obtained through the hydraulic sensor respectively;

[0033] S13, obtaining the oil pressure information P （0，0） ...P （0，n） , and the corresponding weight M （0，0） ...M （0，n） linear or curve fitting is performed to obtain the relationship between the oil pressure of the oil cylinder 13 and the weight;

[0034] S14, according to the load oil pressure information P （0，i） , and according to the relationship between the oil pressure of the oil cylinder 13 and the weight, the total weight M 总 is obtained 总 , the weight M （0，0） of the hopper 11 is subtracted to obtain the weight of the material in the hopper 11.

[0035] For example, when the hopper 11 is empty, the empty weight M (0,0) = 100 kg (self weight of the hopper 11), and the corresponding oil pressure P(0,0) = 10 MPa; At this time, a standard weight is added to the hopper 11, for example:

[0036] When 50 kg of material is added, the total weight M (0,1) = 150 kg; the measured oil pressure P (0,1) = 15 MPa;

[0037] When 100 kg of material is added, the total weight M(0,2) = 200 kg; the measured oil pressure P(0,2) = 20 MPa;

[0038] The relationship is obtained by linear fitting:

[0039] P = 0.1 × M (the oil pressure increases by 0.1 MPa for every 1 kg of weight);

[0040] When discharging, if the current oil pressure P(0,i) = 18 MPa is measured, substitute into the formula: Mtotal = 18 / 0.1 = 180 kg; the net weight of the material = 180 kg (total weight) - 100 kg (self weight of the hopper 11) = 80 kg, the weight of the material in the hopper 11 is obtained.

[0041] Further, in step S2, the obtaining of the empty oil pressure change information specifically includes:

[0042] When the hopper 11 is horizontally empty, the servo electric push rod 12 is used to push the hopper 11 to move, and the oil pressure information P corresponding to the servo electric push rod 12 at different positions x is recorded （x，0）Thus, the influence of the torque change of the servo electric push rod 12 due to the movement on the oil cylinder 13 is obtained, and the detection accuracy of the discharging rate is increased.

[0043] Specifically, in step S2, during discharging, the servo electric push rod 12 is controlled to push the push plate 111 at an initial pushing speed, and the load oil pressure change information of the oil cylinder 13 at different positions of the extension end of the servo electric push rod 12 is obtained in real time through the hydraulic sensor. The controller further obtains the change amount of the material in the hopper 11 per unit time according to the difference between the load oil pressure change information and the no-load oil pressure change information, and further obtains the discharging rate per unit time, specifically including:

[0044] During discharging, the servo electric push rod 12 is controlled to push the push plate 111 at an initial pushing speed, and the load oil pressure information P of the oil cylinder 13 at different positions x of the extension end of the servo electric push rod 12 is obtained in real time through the hydraulic sensor. （x，i） The different load oil pressure information P （x，i） is subtracted from the corresponding oil pressure information P （x，0） to obtain the oil pressure information ΔP of the net weight of the material at different positions x. （x，i） Then, the net weight information of the material at different positions x is obtained according to the relationship between the oil pressure of the oil cylinder 13 and the weight, and finally the discharging rate is obtained according to the net weight information at the two time points.

[0045] As a further improvement of the structure of the charging car 10, the charging car 10 further comprises a temperature sensor for measuring the oil temperature of the oil cylinder 13. When the charging car 10 is discharging, the control method further comprises:

[0046] S4, the oil temperature of the oil cylinder 13 is obtained through the temperature sensor, and the oil pressure data is compensated and corrected according to the relationship model of the oil temperature and the oil pressure, to ensure that the material weight can be accurately measured under different temperature conditions. Specifically, when the charging car 10 is discharging, the control method further comprises:

[0047] S5, whether the oil temperature of the oil cylinder 13 has abnormal fluctuations is judged, and if so, the work is ended and a warning is given.

[0048] Specifically, a static or dynamic threshold (such as an instantaneous change rate > 0.5°C / s or a continuous 3 times exceeding 0.3°C / s) is set. When the system detects that the oil temperature suddenly rises from 50°C to 65°C (change rate 1.5°C / s) within 10 seconds, which is far beyond the preset threshold 0.5°C / s. The controller immediately controls the charging car 10 to end the work and give a warning.

[0049] The control method further comprises:

[0050] S6. Determine if there are any abnormal fluctuations in the oil pressure data. If so, end the work and issue a warning. Fluctuations in oil pressure data include: the hopper 11 suddenly receives material exceeding its capacity, causing the feeding vehicle 10 to be overloaded. Specifically, if the fluctuation exceeds the threshold of 0.5 MPa / s, it is marked as a suspicious fluctuation. If, during unloading, the hydraulic sensor detects that the oil pressure suddenly drops from 15 MPa to 8 MPa (ΔP=7 MPa, Δt=2 seconds), exceeding the threshold (0.5 MPa / s), end the work and issue a warning, and manually intervene to troubleshoot the fault.

[0051] The control methods further include:

[0052] S7, before the feeding vehicle 10 starts working, the controller records the oil pressure information of the hydraulic cylinder 13 each time the push plate 111 reaches the farthest end, and takes the average value of the oil pressure information; when the feeding vehicle 10 is feeding material, when the push plate 111 reaches the farthest end, the controller checks whether the oil pressure information of the hydraulic cylinder 13 is within the threshold range that exceeds the average value. If it exceeds the threshold range, it is determined that there is material residue. At this time, there may be a gap between the push plate 111 and the inner wall of the hopper 11, which may cause some material to be unable to be pushed out of the hopper 11 by the push plate 111. At this time, manual intervention is required for troubleshooting.

[0053] For example: the reference oil pressure P used to measure the oil pressure base =20.0MPa, dynamic threshold 20.0±0.8MPa;

[0054] P was detected during material feeding. current =20.3MPa, within the threshold, indicating no residue;

[0055] When push plate 111 reaches the farthest point, P is detected. current =22.5, exceeding the threshold, the controller determines that there is material residue, and manual intervention is required for investigation.

[0056] This application has two embodiments for the method of obtaining the initial propulsion velocity:

[0057] Example 1: The method for obtaining the initial thrust velocity includes the following steps:

[0058] S31. If the material is rock, calculate the initial pushing speed using the first formula:

[0059] ;

[0060] In the first formula, As the calibration constant, take , The bulk density is obtained from experimental data. is the friction coefficient of the material and the inner wall of the hopper 11, which is obtained through experimental data; is the angle of repose, which is obtained through experimental data;

[0061] S32, if the material is a granular bulk material, humidity compensation is needed. The processor adjusts the humidity value detected by the humidity sensor based on the first formula to obtain the second formula. The initial pushing speed is calculated through the second formula: ;

[0062] In the second formula, is the calibration constant, which is , is the humidity, which is obtained by the humidity sensor installed on the inner wall of the hopper 11, is the bulk density, which is obtained through experimental data, is the friction coefficient of the material and the inner wall of the hopper 11, which is obtained through experimental data; is the angle of repose, which is obtained through experimental data.

[0063] Combined with actual cases:

[0064] Assume that the material to be discharged and the required characteristics are as shown in Table 1:

[0065] Table 1

[0066]

[0067] I. For example, rock needs to be discharged. Since rock is a rock material, the initial discharge rate of rock is obtained by using the formula of step S1 :

[0068] Substituting the formula gives:

[0069] ;

[0070] Conversion gives: ;

[0071] The formula is simplified to only consider density, friction and angle of repose. The processor controls the servo electric push rod 12 to discharge according to the discharge rate controlled by the controller.

[0072] II. For example, sand needs to be discharged. Since sand is a granular bulk material, the initial discharge rate of sand is obtained by using the formula of step S2 :

[0073] Substituting the formula gives:

[0074] ;

[0075] Calculation steps:

[0076] Density and friction terms: ;

[0077] Rest angle correction: , reciprocal ;

[0078] Humidity correction: ;

[0079] Integrated calculation:

[0080] ;

[0081] Humidity 8% causes a speed reduction of 8%, the processor controls the servo electric push rod 12 through the controller to control the servo electric push rod 12 according to the unloading rate Unloading.

[0082] III, for example, the need to unload the coal block, because the sand is a granular bulk material, then use the formula of step S2 to obtain the initial unloading rate of sand :

[0083] Substitute the formula to get:

[0084] ;

[0085] Calculation steps:

[0086] Density and friction terms: ;

[0087] Rest angle correction: , reciprocal ;

[0088] Humidity correction: ;

[0089] Integrated calculation:

[0090] ;

[0091] Humidity 12% causes a speed reduction of 12%, the processor controls the servo electric push rod 12 through the controller to control the servo electric push rod 12 according to the unloading rate Unloading:

[0092] The results of the first embodiment are shown in Table 2:

[0093] Table 2

[0094]

[0095] Example two:

[0096] The method for obtaining the initial pushing speed comprises the following steps:

[0097] S41, using Jenike flow theory correction formula, calculate the critical flow velocity of the material:

[0098] ;

[0099] Wherein, is the cohesion of the material; is the dynamic friction coefficient between the material and the inner wall of the hopper 11; is the density of the material; is the depth of the hopper 11;

[0100] S42, calculate the initial pushing speed , wherein 0.8 is the safety factor for preventing accumulation;

[0101] Combined with actual cases:

[0102] The material for discharging and the assumed characteristics are shown in Table 3:

[0103] Table 3

[0104]

[0105] For example, it is required to discharge rock:

[0106] Step one, calculate the critical speed:

[0107] Cohesion term conversion: ;

[0108] Critical speed:

[0109] ;

[0110] Optimal initial speed:

[0111] ;

[0112] The controller controls the travel rate of the servo electric push rod 12 to be ;

[0113] For example, it is required to discharge sand:

[0114] Step one, calculate the critical speed:

[0115] ;

[0116] Wherein, the cohesion term: ;

[0117] Molecular calculation: ;

[0118] Critical velocity:

[0119] Optimal initial velocity:

[0120] For example, the coal blocks need to be discharged:

[0121] Calculate the critical velocity:

[0122]

[0123] Cohesion term:

[0124] The cohesion term is calculated as follows:

[0125] Critical velocity:

[0126] Optimal initial velocity:

[0127] Compared with Example 2, the humidity factor and the angle of repose are considered in Example 1. Because the rock has low humidity sensitivity, large particles, and low porosity, it is difficult for water to form a liquid bridge, and the friction coefficient and flowability are less affected by humidity changes, so the first formula is used for rock materials. The sand and coal have high humidity sensitivity. The sand particles are small and have a large specific surface area. The increase in moisture significantly enhances the liquid bridge force between particles, leading to caking and a decrease in flowability. The coal is a porous material that easily absorbs water. The increase in humidity causes the particles to soften and the viscosity to rise, resulting in significant changes in cohesion and friction coefficient. Therefore, the second formula is used to calculate the discharge rate.

[0128] Finally, the optimal discharge rate data calculated in the above steps are formed into a query table, as shown in Table 3. The discharge rate is recorded in the information of the material. In the next discharge, the actual speed is replaced with the initial discharge rate, and the processor detects in real time during the discharge of the same material and adjusts the discharge rate in real time according to the actual situation. After a limited number of discharges, the processor summarizes the optimal discharge rate of the material. The optimal discharge rate is the average of the actual discharge rate of the material each time;

[0129] Further, a vibration motor is also installed at the bottom of the hopper 11. Specifically, the vibration motor uses a vibration motor with a frequency of 10-100 Hz, and the control method further includes:

[0130] If the material is a high-stick material, such as wet coal slurry, the processor starts the vibration motor to vibrate the hopper 11 at the first frequency to assist in discharging during the discharging process;

[0131] ​​​​​​​If the material is a fragile material, such as activated carbon, the processor starts the vibration motor to vibrate the hopper 11 according to the second frequency during the discharging process.

[0132] The first frequency is greater than the second frequency, specifically, the first frequency is 100 Hz, and the second frequency is 10 Hz.

[0133] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0134] Those skilled in the art should understand that the above embodiments are only for clearly illustrating the present application, and are not intended to limit the scope of the present application. Based on the above disclosure, other changes or modifications can also be made by those skilled in the art, and these changes or modifications are still within the scope of the present application.

Claims

1. A method of controlling the discharge of a charging car, characterized by: The front end of the charging trolley is provided with a hopper through an oil cylinder, the oil cylinder is used to lift the hopper, a push plate that can move forward and backward is arranged in the hopper, a servo electric push rod that is used to push the push plate is arranged behind the hopper, and the extension end of the servo electric push rod is connected with the push plate; the charging trolley is further provided with a hydraulic sensor that is arranged on the oil cylinder and is used to detect the oil pressure information in the oil cylinder, and a controller that is connected with the hydraulic sensor and the servo electric push rod respectively; The controller is used to calculate the weight of the material in the hopper according to the oil pressure information and control the advancing speed of the extension end of the servo electric push rod; The control method comprises the following steps: S1, the controller controls the oil cylinder to make the hopper be in a horizontal position, acquires the load oil pressure information in the oil cylinder through the hydraulic sensor, and further acquires the weight of the material in the hopper according to the difference between the load oil pressure information and the no-load oil pressure information, wherein the no-load oil pressure information is the oil pressure information recorded when the hopper is in a horizontal no-load state and the extension end of the servo electric push rod is in an initial position; S2, when discharging, the servo electric push rod is controlled to push the push plate to discharge at an initial pushing speed, the load oil pressure change information in the oil cylinder when the extension end of the servo electric push rod is in different positions is acquired in real time through the hydraulic sensor, the controller further acquires the change amount of the material in the hopper per unit time according to the difference between the load oil pressure change information and the no-load oil pressure change information, and then acquires the discharging rate per unit time, wherein the no-load oil pressure change information is the oil pressure information recorded when the hopper is in a horizontal no-load state and the servo electric push rod is in different positions; S3, whether the discharging rate is in a preset range is judged, if yes, the push plate is pushed to discharge at the initial pushing speed, and if not, the initial pushing speed is corrected to control the discharging rate to be in the preset range.

2. The method of controlling the discharge of a charging car according to claim 1, wherein: In step S1, the controller controls the oil cylinder to make the hopper be in a horizontal position, acquires the load oil pressure information in the oil cylinder through the hydraulic sensor, and further acquires the weight of the material in the hopper according to the difference between the load oil pressure information and the no-load oil pressure information, which specifically comprises the following steps: S11, when the hopper is in a horizontal empty state, acquiring load oil pressure information P in the oil cylinder through the hydraulic sensor （0，0） , and recording the weight M of the hopper （0，0） ; S12, different weights of load M （0，1） , M （0，2） ,... M （0，n） , are placed on the hopper, and the load oil pressure information P （0，1） , P （0，2） ,... P （0，n） in the oil cylinder is respectively acquired by the hydraulic sensor. S13, obtaining the oil pressure information P （0，0） ...P （0，n） with the corresponding weight M （0，0） ...M （0，n） performing linear or curve fitting to obtain a relationship between the oil pressure of the oil cylinder and the weight S14, based on the load oil pressure information P （0，i） and the relationship between the oil pressure of the cylinder and the weight, the total weight M is obtained 总 The total weight M 总 is subtracted from the weight M （0，0） of the hopper to obtain the weight of the material in the hopper.

3. The method of controlling the discharge of a charging car according to claim 2, wherein: In step S2, the acquisition of the no-load oil pressure change information specifically comprises the following steps: When the hopper is in a horizontal empty state, the hopper is moved by the servo electric push rod, and the oil pressure information P corresponding to different positions x of the servo electric push rod is recorded （x，0） Thus, the influence of the change of the moment of the servo electric push rod due to movement on the oil cylinder is obtained.

4. The method of controlling the discharge of a charging car according to claim 3, wherein: In step S2, when discharging, the servo electric push rod is controlled to push the push plate to discharge at an initial pushing speed, the load oil pressure change information in the oil cylinder when the extension end of the servo electric push rod is in different positions is acquired in real time through the hydraulic sensor, the controller further acquires the change amount of the material in the hopper per unit time according to the difference between the load oil pressure change information and the no-load oil pressure change information, and then acquires the discharging rate per unit time, which specifically comprises the following steps: When discharging, the servo electric push rod is controlled to push the push plate at an initial pushing speed, and the load oil pressure information P in the oil cylinder at different positions x of the extension end of the servo electric push rod is acquired in real time through the hydraulic sensor （x，i） ; the different load oil pressure information P （x，i） is subtracted from the corresponding oil pressure information P （x，0） to obtain the oil pressure information ΔP of the net weight of the material at different positions x （x，i） , then the net weight information of the material at different positions x is acquired according to the oil pressure change relationship of the oil cylinder with the weight, and finally the discharging rate is acquired according to the net weight information at the two time points.

5. The method of controlling the discharge of a batch car according to claim 1 wherein: The charging trolley further comprises a temperature sensor that is used to measure the oil temperature of the oil cylinder.

6. The method of controlling the discharge of a charging car according to claim 5, wherein: When the charging trolley discharges, the control method further comprises the following steps: S4, the temperature sensor acquires the oil temperature of the oil cylinder, and compensates and corrects the oil pressure data according to the relationship model of the oil temperature and the oil pressure, so as to ensure that the material weight can be accurately measured under different temperature conditions.

7. The method of controlling the discharge of a charging car according to claim 6, wherein: When the charging vehicle is discharging, the control method further comprises: S5, judging whether the oil temperature of the oil cylinder has abnormal fluctuation, and if yes, ending the work and giving a warning.

8. The method of controlling the discharge of a charging car according to claim 7, wherein: When the charging vehicle is discharging, the control method further comprises: S6, judging whether the oil pressure data has abnormal fluctuation, and if yes, ending the work and giving a warning.

9. The discharging control method of the charging vehicle according to claim 8, characterized in that: The control method further comprises: S7, before the charging vehicle works, the controller records the oil pressure information of the oil cylinder when the push plate reaches the farthest end each time, and takes the average value of the oil pressure information; when the charging vehicle is discharging, when the push plate reaches the farthest end, the controller checks whether the oil pressure information of the oil cylinder is within the threshold range of the average value, and if not, it is determined that there is residual material.

Images