Mining dump truck lifting system with load capacity detection function and using method thereof

Abstract

The invention relates to a mining dump truck lifting system with a load capacity detection function and a using method thereof, the mining dump truck lifting system comprises a lifting pump connected with a hydraulic oil tank, the lifting pump is connected with a lifting oil cylinder through a lifting proportional valve, a rodless cavity of the lifting oil cylinder is provided with a pressure sensor, a lifting angle sensor is arranged on a carriage of a mining dump truck, and a slope sensor is arranged on a truck body. The system further comprises a controller, the input end of the controller is connected with the pressure sensor, the lifting angle sensor and the gradient sensor, and the output end of the controller is connected with the lifting pump and the lifting proportional valve. The controller controls the lifting proportional valve to drive the lifting pump to lift in a small range, pressure value calibration in the reference state, the no-load state and the full-load state is achieved, after calibration of the three states is completed, load capacity detection is conducted, the load capacity of the vehicle is calculated, and the system is few in part, easy to install and maintain, low in cost and high in reliability. Automatic diagnosis of the detection system can be realized, so that system errors are reduced, and faults are eliminated.

Description

Technical Field

[0001] The invention relates to the technical field of engineering machinery, in particular to a mining dump truck lifting system with load capacity detection function and a use method thereof. Background Art

[0002] The lifting system of a mining dump truck, that is, the unloading system, is the key function of a mining dump truck and also the basic function of a mining dump truck. The load capacity of a mining dump truck has a significant impact on the operating efficiency, operating safety and equipment life of the lifting system. The application scenarios of the load detection device for mining dump trucks include mining transport vehicles, muck trucks, etc. It is mainly used to monitor the weight of the vehicle in real time, helping drivers and managers to understand the vehicle load in a timely manner, avoid overloading, and ensure transportation safety. This equipment can identify the weight of the vehicle without passing the scale, which is particularly suitable for freight overload control scenarios.

[0003] Therefore, in recent years, the demand for load weight detection function of mining dump trucks has been increasing. The existing solution is usually to configure a set of sensors for collecting vehicle load-related signals for customers in addition to the lifting system to achieve this function. The main equipment for load weight detection of mining dump trucks includes load sensors, data collectors and display instruments. The load sensors are responsible for sensing the load weight of the vehicle. Usually, there are multiple sensors distributed in different positions of the vehicle to provide more accurate measurements. The data collector is responsible for processing, calibrating and transmitting the weight signals of each sensor, and can transmit the weight information to GPS or other display devices through the interface. The display instrument is responsible for displaying the weight information in real time, and usually has the function of displaying tare weight and net weight, with high display clarity. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a mining dump truck lifting system with simple structure, good effect and load capacity detection and a use method thereof.

[0005] The present invention is implemented with the following technical scheme: a lifting system for a mining dump truck with load detection, comprising a lifting pump connected to a hydraulic oil tank, the lifting pump being connected to a lifting cylinder via a lifting proportional valve, the rodless chamber of the lifting cylinder being provided with a pressure sensor, a lifting angle sensor being provided on the carriage of the mining dump truck, a slope sensor being provided on the vehicle body, and also comprising a controller, the input end of the controller being connected to the pressure sensor, the lifting angle sensor and the slope sensor, and the output end of the controller being connected to the lifting pump and the lifting proportional valve.

[0006] Furthermore, the lifting pump is an electrically controlled variable displacement pump.

[0007] The lifting proportional valve is a four-position four-way electromagnetic proportional valve, and the four working positions of the lifting proportional valve are lifting, holding, floating and lowering working conditions.

[0008] The pressure sensor is used to detect the lifting pressure of the cargo box, the lifting angle sensor is used to detect the lifting angle of the cargo box relative to the frame; the slope sensor is used to detect the slope information of the vehicle.

[0009] A method for using a mining dump truck lifting system with load detection, when the cargo box falls to the bottom and is placed horizontally, the reference state, the empty state and the full load state are calibrated in sequence to establish an initial model of the vehicle load, and after the initial model is established, the load detection is performed; The cargo box falls to the bottom, and the controller detects the lifting angle sensor; The vehicle is placed horizontally, which is accomplished by the controller detecting the slope sensor; Baseline state calibration: when the cargo box falls to the bottom and the vehicle is placed horizontally, calibrate the pressure value of the pressure sensor in the base state; No-load state calibration: when the vehicle is in an unloaded state, first calibrate the reference state, and then calibrate the pressure sensor when the vehicle can overcome the weight of the cargo box. Full load state calibration: When the vehicle is at rated load, first perform a baseline state calibration to calibrate the pressure sensor to the lifting pressure value that the vehicle can overcome the total weight of the cargo box and materials; Load capacity detection: When the cargo box falls to the bottom, the slope of the vehicle is detected and recorded, the pressure value of the pressure sensor is calibrated, and the difference between the recorded slope value and the calibration parameters of the reference state, empty state and full load state is calculated to estimate the weight of the cargo in the cargo box and display it to the user; Each time the vehicle is started or at regular intervals, the controller automatically initiates a calibration of the baseline state and no-load state.

[0010] When detecting that the cargo box has fallen to the bottom, the lifting angle sensor detects that the lifting angle of the cargo box is less than 2% and does not change within 1 second, and determines that the cargo box has fallen to the bottom.

[0011] When detecting that the vehicle is placed horizontally, the slope sensor detects that the slope of the vehicle is within ±1% and determines that the vehicle is placed horizontally.

[0012] During the calibration process of the reference state, when the pressure value of the pressure sensor is between 0-2 bar, it is the pressure value of the reference state of the pressure sensor.

[0013] During the no-load calibration, full-load calibration and load weight detection processes, the hydraulic pump always runs at the lowest operating speed. The controller controls the lifting proportional valve to enter the maximum opening of the lifting position for 0.5 seconds, so that the lifting cylinder pushes the cargo box to lift a small amplitude. The controller will obtain the maximum pressure value of the pressure sensor during this small amplitude lifting process as the calibration pressure value.

[0014] During the calibration process in the no-load state, the calibration pressure value of the pressure sensor shall not exceed 50% of the maximum working pressure of the lift pump 2; during the calibration process in the full-load state, the calibration pressure value of the pressure sensor shall not exceed the maximum working pressure of the lift pump 2.

[0015] The method for estimating the weight of the cargo in the cargo box is: estimated load value = slope coefficient × rated load of the vehicle × (pressure value of load detection - pressure value of empty load calibration) / (pressure value of full load calibration - pressure value of load detection), where slope coefficient = square root of (1 + square of slope).

[0016] The present invention has the following advantages: the mining dump truck lifting system with load detection and the use method of the present invention, through the controller to control the lifting proportional valve to drive the lifting pump to lift slightly, to achieve pressure value calibration in the reference state, no-load state and full-load state, after completing the calibration of the reference state, no-load state and full-load state, to perform load detection to achieve vehicle load calculation, the setting process of the vehicle load detection is simple and time-saving, and at the same time, the system has few parts, is easy to install and maintain, and has low cost, and can achieve automatic diagnosis of the detection system to reduce system errors and eliminate faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are part of the present invention and are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the accompanying drawings described below are only some embodiments. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0018] In the attached picture: Figure 1 is a schematic structural diagram of embodiment 1 of the present invention; Figure 2 It is a structural schematic diagram of embodiment 2 of the present invention.

[0019] In the figure: 1. hydraulic oil tank, 2. lifting pump, 3. lifting proportional valve, 4. lifting cylinder, 5. pressure sensor, 6. lifting angle sensor, 7. slope sensor, 8. controller.

[0020] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0022] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0023] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] like Figure 1 to Figure 2A lifting system for a mining dump truck with load detection is shown, comprising a lifting pump 2 connected to a hydraulic oil tank 1, wherein the lifting pump 2 is connected to a lifting cylinder 4 via a lifting proportional valve 3, wherein a pressure sensor 5 is provided in the rodless chamber of the lifting cylinder 4, a lifting angle sensor 6 is provided on the carriage of the mining dump truck, a slope sensor 7 is provided on the vehicle body, and a controller 8 is also included, wherein an input end of the controller 8 is connected to the pressure sensor 5, the lifting angle sensor 6 and the slope sensor 7, and an output end of the controller 8 is connected to the lifting pump 2 and the lifting proportional valve 3. The mining dump truck lifting system with load detection of the present invention comprises a lifting pump, a lifting proportional valve and a lifting oil cylinder, as well as a pressure sensor connected to the rodless cavity of the lifting oil cylinder, a lifting angle sensor for detecting the lifting angle of the carriage, a slope sensor for detecting the slope of the vehicle and a controller; the lifting pump has a minimum working speed, a maximum working speed and a maximum working pressure, the speed of the lifting pump is controlled by the controller, the lifting pump sucks oil from the oil tank and supplies oil to the lifting proportional valve, the lifting proportional valve is connected to the lifting oil cylinder and is controlled by the controller; the lifting oil cylinder is connected to the frame and the cargo box, When the lifting cylinder is extended, it pushes the cargo box to lift and realize the dumping of materials. A pressure sensor is connected to the large chamber of the lifting cylinder to detect the pressure in the large chamber of the lifting cylinder. The controller will receive the signal of the pressure sensor and use it to calculate and calibrate the vehicle load detection; with the help of the lifting system, the controller detects the lifting pressure in a small lifting process to obtain the lifting pressure that can overcome the total weight of the cargo box and materials, thereby calculating the vehicle load. The system not only has good detection effect, but also has a simple structure, low cost, easy installation and maintenance, and is convenient for subsequent use and maintenance.

[0025] like Figure 1The lifting system of a mining dump truck with load detection is shown, wherein the lifting pump 2 is an electrically controlled variable displacement pump. The lifting proportional valve 3 is a four-position four-way electromagnetic proportional valve, and the four working positions of the lifting proportional valve 3 are lifting, holding, floating and lowering working conditions. The lifting cylinder 4 is a single-stage double-acting lifting cylinder. The lifting proportional valve of the present invention is an electrically controlled proportional valve. The lifting proportional valve controls the opening of the valve core at a certain position based on the received electrical signal. The working positions of the lifting proportional valve are the valve cores of four positions, namely, lifting, holding, floating and descending, from right to left. The electrical signal emitted by the control valve can control the opening of the valve core at a certain position, so as to limit the movement speed of the lifting cylinder with the flow capacity of the valve core at this position; when the valve core is in the lifting position, the lifting pump supplies oil to the rodless cavity of the lifting cylinder through the lifting proportional valve, pushes the cylinder to extend, and realizes the dumping of materials; when the valve core is in the holding position, all the oil ports of the lifting cylinder are blocked, and the cargo box is in a locked state and cannot be moved; when the valve core is in the floating position, all the cavities in the lifting cylinder are connected to the oil tank through the valve core, and all the cavities in the lifting cylinder are connected to the oil tank through the valve core. The electrical signal can control the opening of the valve core of the lifting proportional valve in the floating position, so as to limit the flow capacity of the oil in all the cavities of the lifting cylinder back to the oil tank through the valve core, and prevent the cargo box from falling quickly and causing impact. When the lifting angle of the cargo box is small, the cargo box and the materials inside the cargo box can push the oil cylinder back into the cylinder under the action of gravity, so that the cargo box can automatically fall. When the valve core is in the descending position, the lifting pump supplies oil to the rodless chamber of the lifting cylinder through the lifting proportional valve, pushing the cylinder back and pulling the cargo box down. When the lifting angle of the cargo box is too large, the gravity of the cargo box and the goods cannot push the lifting cylinder back. The pressure oil can be used to push the cylinder back through the descending position of the lifting proportional valve to achieve the fall of the cargo box.

[0026] like Figure 2 The lifting system of a mining dump truck with load detection is shown in the figure, wherein the lifting pump 2 is a fixed-displacement pump, the lifting proportional valve 3 is a three-position four-way electromagnetic proportional valve, and the lifting cylinder 4 is a multi-stage single-acting lifting cylinder. The lifting pump, lifting proportional valve and lifting cylinder of the present invention can also adopt a combination of a fixed-displacement pump, a three-position four-way electromagnetic proportional valve and a multi-stage single-acting lifting cylinder, and the lifting valve has a valve core with at least three positions of lifting, holding and floating. This combination can also realize the function of vehicle load detection and further reduce costs.

[0027] like Figure 1 to Figure 2The lifting system of a mining dump truck with load detection is shown, wherein the pressure sensor 5 is used to detect the lifting pressure of the cargo box, the lifting angle sensor 6 is used to detect the lifting angle of the cargo box relative to the vehicle frame; and the slope sensor 7 is used to detect the slope information of the vehicle. The pressure sensor of the present invention is connected to the rodless cavity of the lifting cylinder to detect the lifting pressure, and its response time does not exceed 2 milliseconds, which is used to calibrate and calculate the vehicle load; the lifting angle sensor is used to detect the lifting angle of the cargo box relative to the vehicle frame, and is also used to calibrate the vehicle load function; the slope sensor is installed on the vehicle frame, and is used to detect the slope information of the vehicle, and is also used to calibrate the vehicle load function.

[0028] A method for using a mining dump truck lifting system with load detection, when the cargo box falls to the bottom and is placed horizontally, the reference state, the empty state and the full load state are calibrated in sequence to establish an initial model of the vehicle load, and after the initial model is established, the load detection is performed; The cargo box falls to the bottom, which is completed by the controller 8 detecting the lifting angle sensor 6; when the cargo box falls to the bottom, the user is required to lower the cargo box to the bottom first. The controller 8 first detects whether the lifting angle of the cargo box is less than 2% through the lifting angle sensor 6. If so, the controller 8 sends a signal to make the lifting proportional valve 3 at the maximum opening of the floating position. If not, an error reminder will be issued; then, the controller 8 detects whether the lifting angle of the cargo box is less than 2% through the lifting angle sensor 6 and does not change within 1 second. If so, the controller 8 will issue a reminder that the cargo box has fallen to the bottom and determine that the cargo box has fallen to the bottom.

[0029] The vehicle is placed horizontally, which is completed by the controller 8 detecting the slope sensor 7; when detecting that the vehicle is placed horizontally, the slope sensor 7 detects that the slope of the vehicle is within ±1%, and determines that the vehicle is placed horizontally.

[0030] Baseline state calibration, when the cargo box falls to the bottom and the vehicle is placed horizontally, calibrate the pressure value of the base state of pressure sensor 5; during the base state calibration process, when the pressure value of pressure sensor 5 is between 0-2bar, it is the pressure value of the base state of pressure sensor 5.

[0031] No-load state calibration: when the vehicle is in an unloaded state, firstly calibrate the reference state, and then calibrate the lifting pressure value of the pressure sensor 5 when the vehicle can overcome the deadweight of the cargo box; Full load state calibration: when the vehicle is at rated load, a reference state calibration is first performed to calibrate the lifting pressure value of the pressure sensor 5 when the vehicle can overcome the total weight of the cargo box and materials; Load capacity detection: when the cargo box falls to the bottom, the slope of the vehicle is detected and recorded, the pressure value of the pressure sensor 5 is calibrated, and the difference between the recorded slope value and the calibration parameters of the reference state, empty state and full load state is calculated to estimate the weight of the cargo in the cargo box and display it to the user; Each time the vehicle is powered on or at regular intervals, the controller 8 automatically initiates a calibration of the baseline state and no-load state. Each time the vehicle is powered on or at regular intervals, the controller automatically initiates a calibration of the baseline state and no-load state to check whether the load function can operate normally, ensure the operating accuracy of the load detection function, and reduce detection errors. When the controller 8 determines that the pressure sensor 5 cannot operate normally during the baseline calibration process, the controller will suspend the use of the load detection function and remind the user to check and repair the pressure sensor 5. During the no-load state calibration process, when the controller 8 determines that the pressure sensor 5 cannot operate normally, the controller will suspend the use of the load detection function and remind the user to check and repair the lifting system.

[0032] The method for using the lifting system of the mining dump truck with load detection of the present invention is as follows: during the calibration of the no-load state, the calibration of the full-load state and the load detection, the hydraulic pump 2 always runs at the lowest working speed, and the controller 8 controls the lifting proportional valve 3 to enter the maximum opening of the lifting position for 0.5 seconds, so that the lifting cylinder 4 pushes the cargo box to lift a small amplitude, and the controller 8 obtains the maximum pressure value of the pressure sensor 5 during this small amplitude lifting process as the calibration pressure value. During the calibration process of the no-load state, the calibration pressure value of the pressure sensor 5 does not exceed 50% of the maximum working pressure of the lifting pump 2; during the calibration process of the full-load state, the calibration pressure value of the pressure sensor 5 does not exceed the maximum working pressure of the lifting pump 2.

[0033] The method for using the lifting system of the mining dump truck with load detection of the present invention, the vehicle load detection function starts from the state where the cargo box falls to the bottom and sequentially completes the calibration of the reference state, the empty state and the full load state to realize the establishment of the initial model of the vehicle load. After the initial model is established, the load detection can be performed. The specific steps are as follows: The calibration process of the reference state requires that the vehicle cargo box be lowered to the bottom and placed horizontally: S1, the controller 8 detects whether the slope of the vehicle is within ±1% through the slope sensor 7. If not, an error reminder will be issued and calibration will be exited; if yes, proceed to the next step; S2, the controller 8 will determine whether the cargo box has fallen to the bottom. If not, an error reminder will be issued and calibration will be exited; if it is determined to be, the next step will be carried out: S3, when the cargo box falls to the bottom, the rodless chamber of the lifting cylinder 4 is connected to the hydraulic oil tank 1 through the valve core of the lifting proportional valve 3, and the pressure in the large chamber of the lifting cylinder is fully released; S4, the controller determines whether the pressure sensor 5 is normal by detecting the pressure signal of the pressure sensor 5, and uses it as one of the bases for whether the vehicle load detection function can work normally; in this state, when the pressure value of the pressure sensor 5 is between 0-2bar, the controller 8 determines that the pressure sensor 5 works normally, and stores the pressure value of the pressure sensor 5 in this state as the pressure value of the reference state, and at the same time issues a calibration success reminder to complete the calibration of the reference state; S5. When the pressure value of the pressure sensor 5 is not between 0 and 2 bar, the controller 8 determines that the pressure sensor 5 cannot work normally, issues an error reminder, and exits the calibration of the reference state.

[0034] Only after the calibration of the reference state is completed, can the calibration of the empty state be entered. The calibration process of the empty state requires that the vehicle cargo box falls to the bottom, is placed horizontally and is in an empty state: T1, the controller 8 detects whether the slope of the vehicle is within ±1% through the slope sensor 7. If not, an error reminder will be issued and calibration will be exited. If yes, the next step will be carried out; T2, the controller 8 will determine whether the cargo box has fallen to the bottom. If not, it will issue an error reminder and exit the calibration; if it is, proceed to the next step; T3, the controller 8 will limit the lift pump 2 to always run at the lowest operating speed, and start recording the pressure signal of the pressure sensor 5; T4, the controller 8 sends an electrical signal to make the lifting proportional valve 3 enter the maximum opening of the lifting position for 0.5 seconds, so that the lifting cylinder 4 pushes the cargo box to lift a small amplitude, and the controller 8 obtains the maximum pressure value of the pressure sensor 5 during this small amplitude lifting process; T5. When the pressure value exceeds 50% of the maximum working pressure of the lift pump 2, the controller 8 determines that the pressure sensor 5 cannot work normally, the controller 8 issues an error reminder, and exits the calibration of the no-load state; T6, when the pressure value does not exceed 50% of the maximum working pressure of the lifting pump 2, the controller 8 stores the pressure value as the lifting pressure of the vehicle to overcome the deadweight of the cargo box; T7, the controller 8 sends a signal to put the lifting proportional valve 3 in the floating position, so that the cargo box falls back to the frame by its own weight; T8. When the controller 8 detects through the lifting angle sensor 6 that the lifting angle of the cargo box does not change within 1 second, the controller 8 issues a success reminder and completes the calibration of the empty state.

[0035] Only after the calibration of the empty state is completed, the calibration of the fully loaded state can be carried out. The calibration process of the fully loaded state requires that the vehicle cargo box falls to the bottom, is placed horizontally and is in the rated fully loaded state: E1. The controller 8 detects whether the slope of the vehicle is within ±1% through the slope sensor 7. If not, an error reminder will be issued and calibration will be exited; if yes, proceed to the next step: E2. The controller 8 determines whether the cargo box has fallen to the bottom. If not, an error reminder will be issued and calibration will be exited. If it is determined to be, the next step will be carried out: E3, the controller 8 limits the hydraulic pump 2 to always run at the lowest operating speed, and starts to record the pressure signal of the pressure sensor 5; E4, the controller 8 sends an electrical signal to make the lifting proportional valve 3 enter the maximum opening of the lifting position for 0.5 seconds, so that the lifting cylinder 4 pushes the cargo box to lift a small amplitude, and the controller 8 obtains the maximum pressure value of the pressure sensor 5 during this small amplitude lifting process; E5. When the pressure value exceeds the maximum working pressure of the lift pump 2, the controller 8 issues an error reminder and exits the calibration of the full load state; E6. When the pressure does not exceed the maximum working pressure of the lifting pump 2, the controller 8 stores the pressure value as the lifting pressure that the vehicle can use to overcome the total weight of the cargo box and the materials; E7, the controller 8 sends a signal to make the lifting proportional valve 3 at the minimum opening of the floating position, and the fully loaded cargo box and materials fall back onto the frame at a lower falling speed to prevent the fully loaded cargo box and materials from falling rapidly and causing a major impact; the major impact caused by the fully loaded cargo box and materials falling rapidly will cause damage to the frame, discomfort to the driver in the cab, and spillage of materials in the cargo box; E8. When the controller 8 detects through the lifting angle sensor 6 that the lifting angle of the cargo box does not change within 1 second, the controller issues a success reminder and sets the lifting proportional valve 3 to the maximum opening in the floating position to complete the calibration of the full load state.

[0036] The load detection function can work properly only after the reference state, no-load state and full-load state calibration are completed: P1. The user sends a request for the load detection function; P2, the controller 8 determines whether the cargo box has fallen to the bottom. If not, the controller 8 reminds the user to lower the cargo box to the bottom first; if it is determined to be, the controller 8 detects the slope of the vehicle through the slope sensor 7 and records it; P3, the controller 8 will limit the hydraulic pump 2 to always run at the lowest working speed, and start recording the pressure signal of the pressure sensor 5; P4, the controller 8 sends an electrical signal to make the lifting proportional valve 3 enter the maximum opening of the lifting position for 0.5 seconds, so that the lifting cylinder 4 pushes the cargo box to lift a small amplitude. The controller 8 will obtain the maximum pressure value of the pressure sensor 5 during this small amplitude lifting process; P5, the controller 8 will record the pressure value, and combine it with the recorded slope value, and calculate the difference with the calibration parameters of the reference state, empty state and full load state, estimate the weight of the goods in the cargo box, and display it to the user; P6, then the controller 8 sends a signal to make the lifting proportional valve 3 at the minimum opening of the floating position, so that the fully loaded cargo box and materials fall back onto the frame at a lower falling speed; P7. When the controller detects through the lifting angle sensor 6 that the lifting angle of the cargo box does not change within 1 second, the controller 8 sends a signal to make the lifting proportional valve 3 at the maximum opening of the floating position to complete the load capacity detection.

[0037] The method for using the lifting system of a mining dump truck with load detection of the present invention is that the method for estimating the weight of the cargo in the cargo box is: load estimation value = slope coefficient × rated load of the vehicle × (pressure value of load detection - pressure value of no-load calibration) / (pressure value of full-load calibration - pressure value of load detection), wherein, slope coefficient = square root of (1 + square of slope).

[0038] The present invention discloses a mining dump truck lifting system with load detection and a method for using the same. On the basis of realizing the function of the mining dump truck lifting system, the lifting pressure that can overcome the total weight of the cargo box and materials is obtained by detecting the lifting pressure during a small lifting process, and the weight of the materials in the cargo box is estimated by using the slope signal of the slope sensor, the reference state calibration parameters, the empty state calibration parameters and the full load state calibration parameters to calculate the vehicle load. The lifting function is used to realize a simple detection of the vehicle load, thereby reducing the installation cost of the load detection system. In addition, the setting process of the vehicle load detection is simple and time-saving, and the automatic diagnosis of the detection system can be realized to reduce system errors and troubleshoot. Compared with the separately installed weighing system, the advantages of the solution proposed in this application are: high integration with the lifting system, a significant reduction in parts, easy installation and maintenance, low cost, and the ability to automatically diagnose to improve accuracy and troubleshoot.

[0039] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0040] In addition, those skilled in the art will understand that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments also means being within the scope of protection of the present invention and forming different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by this application.

[0041] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A mining dump truck lifting system with load detection, characterized in that: The invention comprises a lifting pump (2) connected to a hydraulic oil tank (1), wherein the lifting pump (2) is connected to a lifting cylinder (4) via a lifting proportional valve (3), wherein a pressure sensor (5) is provided in a rodless chamber of the lifting cylinder (4), a lifting angle sensor (6) is provided on a carriage of a mining dump truck, and a slope sensor (7) is provided on a vehicle body, and further comprises a controller (8), wherein an input end of the controller (8) is connected to the pressure sensor (5), the lifting angle sensor (6) and the slope sensor (7), and an output end of the controller (8) is connected to the lifting pump (2) and the lifting proportional valve (3).

2. A mining dump truck lifting system with load capacity detection as claimed in claim 1, characterized in that: The lifting pump (2) is an electrically controlled variable displacement pump.

3. A mining dump truck lifting system with load capacity detection as claimed in claim 1, characterized in that: The lifting proportional valve (3) is a four-position four-way electromagnetic proportional valve, and the four working positions of the lifting proportional valve (3) are lifting, holding, floating and lowering working conditions.

4. A mining dump truck lifting system with load capacity detection as claimed in claim 1, characterized in that: The pressure sensor (5) is used to detect the lifting pressure of the cargo box, the lifting angle sensor (6) is used to detect the lifting angle of the cargo box relative to the vehicle frame; and the slope sensor (7) is used to detect the slope information of the vehicle.

5. A method for using the mining dump truck lifting system with load capacity detection according to claim 1, characterized in that: When the cargo box falls to the bottom and is placed horizontally, the calibration of the reference state, the empty state and the fully loaded state is completed in sequence to establish the initial model of the vehicle load capacity. After the initial model is established, the load capacity is tested; The cargo box falls to the bottom, which is completed by the controller (8) detecting the lifting angle sensor (6); The vehicle is placed horizontally, and the controller (8) detects the slope sensor (7); Base state calibration, when the cargo box falls to the bottom and the vehicle is placed horizontally, calibrate the pressure value of the pressure sensor (5) in the base state; No-load state calibration: when the vehicle is in an unloaded state, firstly calibrate the reference state, and then calibrate the pressure sensor (5) at the lifting pressure value at which the vehicle can overcome the deadweight of the cargo box; Full load state calibration: when the vehicle is at rated load state, a reference state calibration is first performed to calibrate the pressure sensor (5) at the lifting pressure value that the vehicle can overcome the total weight of the cargo box and materials; Load detection, when the cargo box falls to the bottom, the slope of the vehicle is detected and recorded, the pressure value of the pressure sensor (5) is calibrated, and the difference between the recorded slope value and the calibration parameters of the reference state, the empty state and the full load state is calculated to estimate the weight of the cargo in the cargo box and display it to the user; Each time the vehicle is started or at regular intervals, the controller (8) automatically initiates calibration of the reference state and the no-load state.

6. The method for using the mining dump truck lifting system with load capacity detection as claimed in claim 5, characterized in that: When detecting that the cargo box has fallen to the bottom, the lifting angle sensor (6) detects that the lifting angle of the cargo box is less than 2% and does not change for 1 second, and determines that the cargo box has fallen to the bottom.

7. The method for using the mining dump truck lifting system with load capacity detection as claimed in claim 5, characterized in that: When detecting that the vehicle is placed horizontally, the slope sensor (7) detects that the slope of the vehicle is within ±1%, and determines that the vehicle is placed horizontally.

8. The method for using the mining dump truck lifting system with load capacity detection as claimed in claim 5, characterized in that: During the calibration process of the reference state, when the pressure value of the pressure sensor (5) is between 0 and 2 bar, it is the pressure value of the reference state of the pressure sensor (5).

9. The method for using the mining dump truck lifting system with load capacity detection as claimed in claim 5, characterized in that: During the process of no-load state calibration, full-load state calibration and load weight detection, the hydraulic pump (2) always runs at the lowest working speed, and the controller (8) controls the lifting proportional valve (3) to enter the maximum opening of the lifting position for 0.5 seconds, so that the lifting cylinder (4) pushes the cargo box to lift a small amplitude. The controller (8) obtains the maximum pressure value of the pressure sensor (5) during this small amplitude lifting process as the calibration pressure value;.

10. The method for using the mining dump truck lifting system with load capacity detection as claimed in claim 9, characterized in that: During the calibration process in the no-load state, the calibration pressure value of the pressure sensor (5) does not exceed 50% of the maximum working pressure of the lift pump 2; during the calibration process in the full-load state, the calibration pressure value of the pressure sensor (5) does not exceed the maximum working pressure of the lift pump 2.

11. The method for using the mining dump truck lifting system with load capacity detection as claimed in claim 5, characterized in that: The method for estimating the weight of the cargo in the cargo box is: estimated load value = slope coefficient × rated load of the vehicle × (pressure value of load detection - pressure value of empty load calibration) / (pressure value of full load calibration - pressure value of load detection), where slope coefficient = square root of (1 + square of slope).

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