System and method for monitoring spading operation load characteristics of electric loader

Abstract

The invention discloses an electric loader spading operation load characteristic monitoring system and method, and aims to solve the problems that the prior art depends on a complex model and is difficult in engineering application. Four monitoring devices are arranged at joints of front and rear axles and a chassis of the loader. Each device is composed of an upper connecting plate, a lower connecting plate, a square strain sensing element, a strain gauge assembly, a strain processing circuit and a calculation processing module. The strain gauge assembly preferably comprises eight metal foil type strain gauges which are symmetrically arranged on the vertical plane of the element and are connected to form a vertical force and transverse force measuring bridge. And the calculation processing module calculates the stress of each point in real time according to the bridge output voltage to realize overall load monitoring. The method comprises the steps of initial calibration, real-time measurement, unbalance loading and sudden change early warning, material weighing, working condition identification and the like, and the risk is dynamically predicted through data comparison. The device is simple in structure, low in cost and high in precision, complex mechanical analysis is avoided, engineering application is easy, and operation safety and efficiency are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of loader technology, and in particular to a system and method for monitoring the load characteristics of an electric loader during digging operations. Background Technology

[0002] Electric loaders are a type of versatile construction machinery, primarily used for loading and unloading bulk materials such as soil, sand, gravel, lime, and coal. They can be used for loading, unloading, transporting, leveling materials, and light digging, offering advantages such as high operating efficiency and speed. They are widely used in construction projects such as highways, railways, buildings, hydropower, ports, and mines. The operating conditions of an electric loader can be divided into several processes: digging, lifting, transporting, and unloading. During digging operations, the bucket is subjected to the resistance of the material during the digging process, which has a certain impact on the working performance of the electric loader. Accurately understanding the load characteristics during the digging process is of great significance for the structural design and safe and efficient operation of the electric loader.

[0003] To achieve online monitoring of the load during loader digging operations, patent CN110793694B discloses a load measurement method for the loader's digging mechanism. This method converts changes in the motion state of the digging mechanism into changes in the force at the hinge point between the digging mechanism and the front frame. By analyzing the force at the hinge point under different working conditions, the load-bearing capacity of the digging mechanism is obtained. However, this method relies on complex mechanical analysis and calculation models and requires prior knowledge of various structural parameters of the electric loader, which presents significant challenges in practical use and makes it difficult to implement in engineering. Therefore, there is an urgent need to invent a simple, effective, and easily implementable device and method for monitoring the load characteristics of electric loaders during digging operations. Summary of the Invention

[0004] The purpose of this invention is to provide a system and method for monitoring the load characteristics of an electric loader during digging operations.

[0005] To achieve the aforementioned objectives, the present invention employs the following technical solution: a load characteristic monitoring system for electric loader digging operations, comprising:

[0006] Four load characteristic monitoring devices are respectively arranged at the positions where the electric loader is connected to the chassis of the electric loader: the left side of the front axle, the right side of the front axle, the left side of the rear axle, and the right side of the rear axle.

[0007] Each of the load characteristic monitoring devices includes:

[0008] The upper connecting plate is used to connect to the chassis of the electric loader;

[0009] The lower connecting plate is used to connect to the axle of the electric loader;

[0010] A strain sensing element is disposed between the upper connecting plate and the lower connecting plate, and the strain sensing element has a square structure;

[0011] The strain gauge assembly consists of multiple metal foil strain gauges arranged on the strain sensing element;

[0012] The strain processing circuit, connected to the strain gauge assembly, includes a vertical force measurement bridge and a lateral force measurement bridge;

[0013] The calculation and processing module is connected to the strain processing circuit of each of the load characteristic monitoring devices. It is used to calculate the vertical force and lateral force in real time based on the output voltage of the vertical force measurement bridge and the lateral force measurement bridge, and to monitor the load characteristics of the digging operation as a whole based on the measurement values ​​of the four load characteristic monitoring devices.

[0014] Preferably, each strain gauge assembly of the load characteristic monitoring device consists of eight identical foil strain gauges, respectively. , , , , , , and .

[0015] Preferably, in each of the load characteristic monitoring devices:

[0016] strain gauge strain gauge strain gauge strain gauge The strain gauges are arranged on a vertical plane of the strain sensing element. and strain gauge The arrangement direction of the strain gauges is perpendicular to the upper connecting plate, and the strain gauges are... and strain gauge The two ends of the strain gauge are aligned respectively; and strain gauge Along perpendicular to the strain gauge The strain gauges are arranged in the following directions, and and strain gauge Located on the same straight line, its extension passes through the strain gauge. The midpoint;

[0017] The strain gauge strain gauge strain gauge strain gauge Arranged on the strain sensing element and strain gauge On another vertical plane symmetrical to the vertical plane, the strain gauge and strain gauge The arrangement direction of the strain gauges is perpendicular to the upper connecting plate, and the strain gauges are... and strain gauge The two ends of the strain gauge are aligned respectively; and strain gauge Along perpendicular to the strain gauge The strain gauges are arranged in the following directions, and and strain gauge Located on the same straight line, its extension passes through the strain gauge. The midpoint.

[0018] Preferably, in each of the load characteristic monitoring devices, the vertical force measuring bridge consists of strain gauges. strain gauge strain gauge and strain gauge Composition, including strain gauges and strain gauge Located on opposite arms of the vertical force measurement bridge, strain gauge and strain gauge Located on opposite arms of the vertical force measurement bridge; the strain gauge and strain gauge The common terminal of the strain gauge is connected to the negative terminal of the power supply for the vertical force measurement bridge. and strain gauge The common terminal of the strain gauge is connected to the positive terminal of the power supply for the vertical force measurement bridge. and strain gauge The common terminal of the connection is used as the positive output terminal of the vertical force measurement bridge, and the strain gauge... and strain gauge The common terminal of the connection is used as the negative output terminal of the vertical force measurement bridge.

[0019] Preferably, in each of the load characteristic monitoring devices, the lateral force measuring bridge consists of strain gauges. strain gauge strain gauge and strain gauge Composition, including strain gauges and strain gauge Located on opposite arms of the transverse force measurement bridge, strain gauge and strain gauge Located on opposite arms of the transverse force measurement bridge; strain gauge and strain gauge The common terminal of the strain gauge is connected to the negative terminal of the power supply for the transverse force measurement bridge. and strain gauge The common terminal is connected to the positive terminal of the power supply for the transverse force measurement bridge, and the strain gauge... and strain gauge The common terminal of the connection is used as the positive output terminal of the transverse force measurement bridge, and the strain gauge... and strain gauge The common terminal of the connection is used as the negative output terminal of the transverse force measurement bridge.

[0020] Preferably, the calculation and processing module is used to receive the real-time measurement values ​​of the vertical force measurement bridge and the lateral force measurement bridge in the strain processing circuit, and to calculate the vertical force acting on the strain sensing element in real time. and lateral force The calculation formula is:

[0021]

[0022] in: The output voltage of the bridge is used to measure vertical force. The output voltage of the bridge is used to measure lateral force. Where is Poisson's ratio, and K is the strain gauge sensitivity coefficient. u is the elastic modulus of the strain sensing element. s Supply voltage to the bridge circuit. This represents the transverse cross-sectional area of ​​the strain sensing element at the location of the strain gauge. This represents the flexural section modulus of the strain-sensing element at the location of the strain gauge. This is the distance from the center of the strain gauge to the upper connecting plate.

[0023] This application also provides a method for monitoring the load characteristics of an electric loader during digging operations, applied to the aforementioned monitoring system, comprising the following steps:

[0024] S1. Install a load characteristic monitoring device at the location where the left side of the front axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the right side of the front axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the left side of the rear axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the rear axle of the electric loader connects to the chassis of the electric loader. During the setup process, ensure that the plane of all strain gauge assemblies for load characteristic monitoring devices is perpendicular to the longitudinal direction of the electric loader body;

[0025] S2. When the electric loader is on a level surface and the bucket is off the ground and stationary, record the load characteristics using the monitoring device. Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement The total mass loaded on the entire electric loader is... for: ,in, Represents gravitational acceleration;

[0026] S3, Real-time measurement of four load characteristic monitoring devices , , , The vertical and lateral force values ​​are denoted as follows: , , , and , , , Vertical load experienced by an electric loader during bucket digging. and lateral load They are respectively:

[0027] ,

[0028] S4. During the material shoveling process, if , This is the eccentric load factor. The value range is 1.2~1.4, indicating that there is an off-center vertical load on the bucket of the electric loader during the material digging process, and the vertical load on the left side of the bucket is significantly greater than that on the right side; if This indicates that during the material scooping process of the electric loader bucket, there is an off-center vertical load phenomenon, and the vertical load on the right side of the bucket is significantly greater than that on the left side.

[0029] S5. During the material shoveling process, if This indicates that there is an uneven lateral load on the bucket of the electric loader during the material scooping process, and the lateral load on the left side of the bucket is significantly greater than that on the right side; if This indicates that there is an uneven lateral load on the bucket of the electric loader during the material digging process, and the lateral load on the right side of the bucket is significantly greater than that on the left side.

[0030] S6. During the material shoveling process, record... They are respectively The difference in vertical force at this moment compared to the previous monitoring moment. Let be the load mutation coefficient, if at a certain moment For positive negative and , The value range is 2.5~3, indicating that the bucket suddenly encountered a sudden change in vertical load at that moment, that is, the bucket encountered a large or hard material during the digging process.

[0031] S7. After the material shoveling is completed and the machine remains stationary, the weight of the material shoveled by the electric loader can be calculated using the measured values ​​of the vertical force from the four load characteristic monitoring devices. The calculation formula is:

[0032] ;

[0033] S8. When lifting or lowering the bucket after the material shoveling process is completed, if Continued decline and A continuous rise indicates that the bucket is in the lifting phase; if Continuously increasing and The continued decline indicates that the bucket is in the lowering phase of the work.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] 1) By arranging a load characteristic monitoring device at the connection between the axle and the chassis, the load characteristics of the electric loader during the digging operation can be easily calculated by using the vertical and lateral forces measured in real time by the load characteristic monitoring device, thus avoiding the shortcomings of traditional analysis and calculation using complex kinematic and mechanical models.

[0036] 2) The load characteristic monitoring device adopts a strain gauge-based measurement method, which has the advantages of simple structure and low cost. At the same time, the reasonable use of the strain measurement bridge eliminates the mutual influence between temperature and different forces, and improves the measurement accuracy of vertical and lateral forces at each point of action.

[0037] 3) By comparing the real-time measurement values ​​of different load characteristic measuring devices, the eccentricity of lateral and vertical loads during the digging process can be dynamically predicted, and the load characteristics of the electric loader during the digging process can be better understood.

[0038] 4) By comparing the rate of change of the measured values ​​of different load characteristic measuring devices at different times, the sudden load situation during the digging operation of the electric loader can be dynamically predicted, providing a basis for the safe operation of the electric loader.

[0039] 5) This invention can also measure the weight of the material in the bucket after the electric loader has finished digging, and can also distinguish between lifting or lowering operation conditions according to the changes in the force of the load characteristic monitoring device, making it more functional.

[0040] Overall, this invention has a simple structure, low cost, is easy to use, and is highly practical, making it easy to promote and apply in engineering projects. Attached Figure Description

[0041] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0042] Figure 1 This is a schematic diagram of the load characteristic monitoring system of the invention.

[0043] Figure 2 A structural diagram of the load characteristic monitoring method of the invention.

[0044] Figure 3 This is a diagram showing the arrangement of strain gauges for vertical force measurement in the load characteristic monitoring device of the invention.

[0045] Figure 4 This is a schematic diagram of the vertical force measurement bridge of the load characteristic monitoring device of the invention.

[0046] Figure 5 This is a diagram showing the arrangement of strain gauges for lateral force measurement in the load characteristic monitoring device of the invention.

[0047] Figure 6 This is a schematic diagram of the transverse force measurement bridge of the load characteristic monitoring device of the invention.

[0048] In the figure: 1-upper connecting plate, 2-lower connecting plate, 3-strain sensing element, 4-strain gauge assembly, 5-strain processing circuit, 6-calculation processing module, 51-vertical force measurement bridge, 52-lateral force measurement bridge. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the specific embodiments are described in detail below with reference to the accompanying drawings. This invention aims to provide a simple, effective, and easily implemented load characteristic monitoring scheme for electric loader digging operations. By optimizing the description of the embodiments, the depth and readability of the technical content are improved. The system of this application is based on the strain measurement principle and, through a carefully designed load characteristic monitoring device and calculation processing module, achieves real-time monitoring of load characteristics during digging operations.

[0050] See Figures 1-6 This application provides a load characteristic monitoring system for digging operations of an electric loader, comprising:

[0051] Four load characteristic monitoring devices are respectively arranged at the connection points of the electric loader's front axle (left side), front axle (right side), rear axle (left side), and rear axle (right side) with the chassis. This symmetrical arrangement ensures the comprehensiveness and accuracy of load measurement, effectively capturing dynamic load changes at various points during digging operations. Each load characteristic monitoring device is ingeniously designed, including an upper connecting plate 1, a lower connecting plate 2, a strain sensing element 3, a strain gauge assembly 4, a strain processing circuit 5, and a calculation processing module 6. The upper connecting plate 1 is used for reliable connection with the electric loader chassis to transmit the overall load; the lower connecting plate 2 is used for stable connection with the axle to withstand ground reaction forces; the strain sensing element 3 adopts a square structure and is set between the upper and lower connecting plates to optimize stress distribution and transmission efficiency; the strain gauge assembly 4 consists of multiple metal foil strain gauges to sensitively detect minute strains; the strain processing circuit 5 is connected to the strain gauge assembly and includes a vertical force measurement bridge 51 and a lateral force measurement bridge 52 for signal conditioning and anti-interference processing; the calculation processing module 6 integrates and processes the output data of all devices to achieve real-time calculation and overall monitoring of the load characteristics during digging operations. The system's modular design reduces installation complexity and improves engineering applicability.

[0052] To ensure measurement accuracy and reliability, in one embodiment of this application, each strain gauge assembly 4 of the load characteristic monitoring device consists of eight identical metal foil strain gauges, namely... , , , , , , and This selection of the number of strain gauges is based on mechanical analysis, ensuring simultaneous detection of strain in multiple directions and reducing temperature drift and lateral interference through symmetrical arrangement. The eight strain gauges employ a foil design, offering high sensitivity and small size, facilitating integration into the strain sensing element 3 and improving signal response speed. This configuration provides the foundation for subsequent bridge measurements, ensuring independent calculation of vertical and lateral forces, while redundancy enhances system robustness and avoids single points of failure.

[0053] To optimize the accuracy and consistency of strain detection, in another embodiment of this application, for each load characteristic monitoring device:

[0054] strain gauge strain gauge strain gauge strain gauge Arranged on a vertical plane of the strain sensing element 3, specifically, the strain gauge... and strain gauge The arrangement direction of the strain gauges is perpendicular to the upper connecting plate 1, and the strain gauges are... and strain gauge The two ends are aligned; this vertical alignment design ensures a linear response in vertical force measurement and reduces errors. The strain gauges... and strain gauge Along perpendicular to the strain gauge The strain gauges are arranged in the following directions, and and strain gauge Located on the same straight line, its extension passes through the strain gauge. The midpoint; this layout helps capture bending strain components and improves the sensitivity of lateral force detection.

[0055] Symmetrically, the strain gauge strain gauge strain gauge strain gauge Arranged on strain sensing element 3 and strain gauge On another vertical plane symmetrical to the vertical plane, the strain gauge and strain gauge The arrangement direction of the strain gauges is perpendicular to the upper connecting plate 1, and the strain gauges are... and strain gauge The two ends of the strain gauge are aligned respectively; and strain gauge Along perpendicular to the strain gauge The strain gauges are arranged in the following directions, and and strain gauge Located on the same straight line, its extension passes through the strain gauge. The midpoint ensures measurement consistency and redundancy, enhancing system robustness. This symmetrical arrangement eliminates common-mode interference through differential signals, improving immunity to environmental noise.

[0056] To achieve high-precision measurement of vertical force, in another embodiment of this application, in each of the load characteristic monitoring devices, the vertical force measuring bridge 51 consists of strain gauges. strain gauge strain gauge and strain gauge Composition, including strain gauges and strain gauge Located in the 51st pair of arms of the vertical force measurement bridge, strain gauges and strain gauge Located in the vertical force measuring bridge 51 pairs of arms; the strain gauges and strain gauge The common terminal of the strain gauge is connected to the negative terminal of the power supply of the vertical force measuring bridge 51. and strain gauge The common terminal of the strain gauge is connected to the positive terminal of the power supply of the vertical force measuring bridge 51. and strain gauge The common terminal of the connection is used as the positive output terminal of the vertical force measurement bridge 51, and the strain gauge... and strain gauge The common terminal of the connection serves as the negative output terminal of the vertical force measurement bridge 51. This connection optimizes the linearity of the signal output, making the output voltage proportional to the vertical force, which facilitates subsequent processing. The stable supply voltage of the bridge ensures measurement consistency and reduces errors introduced by power supply fluctuations. This design also minimizes nonlinear effects through a symmetrical layout, improving long-term stability.

[0057] To simultaneously measure lateral loads, this application also includes an embodiment in which, in each of the load characteristic monitoring devices, the lateral force measuring bridge 52 consists of strain gauges. strain gauge strain gauge and strain gauge Composition, including strain gauges and strain gauge Located in the 52 pairs of arms of the transverse force measurement bridge, strain gauges and strain gauge Located in the 52-arm transverse force measurement bridge; strain gauge and strain gauge The common terminal of the strain gauge is connected to the negative terminal of the power supply for the transverse force measurement bridge 52. and strain gauge The common terminal of the strain gauge is connected to the positive terminal of the power supply for the transverse force measurement bridge 52. and strain gauge The common terminal of the connection is used as the positive output terminal of the transverse force measurement bridge 52, and the strain gauge... and strain gauge The common terminal of the connection serves as the negative output of the lateral force measurement bridge 52. This design is specifically optimized for lateral forces, isolating vertical interference through a symmetrical layout, and the output signal directly reflects changes in lateral load. The bridge's high input impedance reduces circuit losses, making it suitable for long-distance signal transmission, while an integrated temperature compensation mechanism ensures accuracy under harsh operating conditions.

[0058] To process the measurement data in real time, the calculation and processing module 6 receives the real-time measurement values ​​of the vertical force measuring bridge 51 and the lateral force measuring bridge 52 in the strain processing circuit 5, and calculates the vertical force acting on the strain sensing element 3 in real time. and lateral force The calculation formula is:

[0059]

[0060] in: The output voltage of the bridge is used to measure vertical force. The output voltage of the bridge is used to measure lateral force. Where is Poisson's ratio, and K is the strain gauge sensitivity coefficient. u is the elastic modulus of the strain sensing element. s Supply voltage to the bridge circuit. This represents the transverse cross-sectional area of ​​the strain sensing element at the location of the strain gauge. This represents the flexural section modulus of the strain-sensing element at the location of the strain gauge. This is the distance from the center of the strain gauge to the upper connecting plate.

[0061] This application also provides a method for monitoring the load characteristics of an electric loader during digging operations, applied to the aforementioned monitoring system, comprising the following steps:

[0062] S1. Install a load characteristic monitoring device at the location where the left side of the front axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the right side of the front axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the left side of the rear axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the rear axle of the electric loader connects to the chassis of the electric loader. During the setup process, ensure that the plane of all load characteristic monitoring device strain gauge assembly 4 is perpendicular to the longitudinal direction of the electric loader body;

[0063] S2. When the electric loader is on a level surface and the bucket is off the ground and stationary, record the load characteristics using the monitoring device. Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement The total mass loaded on the entire electric loader is... for: ,in, Represents gravitational acceleration;

[0064] S3, Real-time measurement of four load characteristic monitoring devices , , , The vertical and lateral force values ​​are denoted as follows: , , , and , , , Vertical load experienced by an electric loader during bucket digging. and lateral load They are respectively:

[0065] ,

[0066] S4. During the material shoveling process, if , This is the eccentric load factor. The value range is 1.2~1.4, indicating that there is an off-center vertical load on the bucket of the electric loader during the material digging process, and the vertical load on the left side of the bucket is significantly greater than that on the right side; if This indicates that during the material scooping process of the electric loader bucket, there is an off-center vertical load phenomenon, and the vertical load on the right side of the bucket is significantly greater than that on the left side.

[0067] S5. During the material shoveling process, if This indicates that there is an uneven lateral load on the bucket of the electric loader during the material scooping process, and the lateral load on the left side of the bucket is significantly greater than that on the right side; if This indicates that there is an uneven lateral load on the bucket of the electric loader during the material digging process, and the lateral load on the right side of the bucket is significantly greater than that on the left side.

[0068] S6. During the material shoveling process, record... They are respectively The difference in vertical force at this moment compared to the previous monitoring moment. Let be the load mutation coefficient, if at a certain moment For positive negative and , The value range is 2.5~3, indicating that the bucket suddenly encountered a sudden change in vertical load at that moment, that is, the bucket encountered a large or hard material during the digging process.

[0069] S7. After the material shoveling is completed and the machine remains stationary, the weight of the material shoveled by the electric loader can be calculated using the measured values ​​of the vertical force from the four load characteristic monitoring devices. The calculation formula is:

[0070] ;

[0071] S8. When lifting or lowering the bucket after the material shoveling process is completed, if Continued decline and A continuous rise indicates that the bucket is in the lifting phase; if Continuously increasing and The continued decline indicates that the bucket is in the lowering phase of the work.

[0072] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A load characteristic monitoring system for digging operations of an electric loader, characterized in that, include: Four load characteristic monitoring devices are respectively arranged at the positions where the electric loader is connected to the chassis of the electric loader: the left side of the front axle, the right side of the front axle, the left side of the rear axle, and the right side of the rear axle. Each of the load characteristic monitoring devices includes: The upper connecting plate (1) is used to connect to the chassis of the electric loader; The lower connecting plate (2) is used to connect to the axle of the electric loader; A strain sensing element (3) is disposed between the upper connecting plate (1) and the lower connecting plate (2), and the strain sensing element (3) has a square structure. The strain gauge assembly (4) consists of multiple metal foil strain gauges arranged on the strain sensing element (3); The strain processing circuit (5), connected to the strain gauge assembly (4), includes a vertical force measuring bridge (51) and a lateral force measuring bridge (52). The calculation processing module (6) is connected to the strain processing circuit (5) of each of the load characteristic monitoring devices. It is used to calculate the vertical force and lateral force in real time based on the output voltage of the vertical force measuring bridge (51) and the lateral force measuring bridge (52), and to monitor the load characteristics of the digging operation as a whole based on the measurement values ​​of the four load characteristic monitoring devices.

2. The load characteristic monitoring system for electric loader digging operations according to claim 1, characterized in that, Each strain gauge assembly (4) of the load characteristic monitoring device consists of eight identical metal foil strain gauges, respectively , , , , , , and .

3. The load characteristic monitoring system for electric loader digging operations according to claim 2, characterized in that, In each of the aforementioned load characteristic monitoring devices: strain gauge strain gauge strain gauge strain gauge The strain gauge is arranged on a vertical plane of the strain sensing element (3). and strain gauge The arrangement direction of the strain gauges is perpendicular to the upper connecting plate (1), and the strain gauges are arranged perpendicular to the upper connecting plate (1). and strain gauge The two ends of the strain gauge are aligned respectively; and strain gauge Along perpendicular to the strain gauge The strain gauges are arranged in the following directions, and and strain gauge Located on the same straight line, its extension passes through the strain gauge. The midpoint; The strain gauge strain gauge strain gauge strain gauge Arranged on the strain sensing element (3) and strain gauge On another vertical plane symmetrical to the vertical plane, the strain gauge and strain gauge The arrangement direction of the strain gauges is perpendicular to the upper connecting plate (1), and the strain gauges are arranged perpendicular to the upper connecting plate (1). and strain gauge The two ends of the strain gauge are aligned respectively; and strain gauge Along perpendicular to the strain gauge The strain gauges are arranged in the following directions, and and strain gauge Located on the same straight line, its extension passes through the strain gauge. The midpoint.

4. The load characteristic monitoring system for electric loader digging operations according to claim 3, characterized in that, In each of the load characteristic monitoring devices, the vertical force measuring bridge (51) consists of strain gauges. strain gauge strain gauge and strain gauge Composition, including strain gauges and strain gauge Located on opposite arms of the vertical force measurement bridge (51), strain gauges and strain gauge Located on opposite arms of the vertical force measuring bridge (51); the strain gauge and strain gauge The common terminal of the strain gauge is connected to the negative terminal of the power supply of the vertical force measuring bridge (51). and strain gauge The common terminal of the strain gauge is connected to the positive terminal of the power supply of the vertical force measuring bridge (51). and strain gauge The common terminal of the connection is used as the positive output terminal of the vertical force measurement bridge (51), and the strain gauge... and strain gauge The common terminal of the connection is used as the negative output terminal of the vertical force measurement bridge (51).

5. A load characteristic monitoring system for electric loader digging operations according to claim 3, characterized in that, In each of the load characteristic monitoring devices, the transverse force measuring bridge (52) consists of strain gauges. strain gauge strain gauge and strain gauge Composition, including strain gauges and strain gauge Located on opposite arms of the transverse force measurement bridge (52), strain gauges and strain gauge Located on the opposite arm of the transverse force measurement bridge (52); strain gauge and strain gauge The common terminal of the strain gauge is connected to the negative terminal of the power supply of the transverse force measuring bridge (52). and strain gauge The common terminal of the strain gauge is connected to the positive terminal of the power supply of the transverse force measuring bridge (52). and strain gauge The common terminal of the connection is used as the positive output of the transverse force measurement bridge (52), and the strain gauge... and strain gauge The common terminal of the connection is used as the negative output terminal of the transverse force measurement bridge (52).

6. The load characteristic monitoring system for electric loader digging operations according to claim 1, characterized in that, The calculation and processing module (6) is used to receive the real-time measurement values ​​of the vertical force measurement bridge (51) and the lateral force measurement bridge (52) in the strain processing circuit (5), and to calculate the vertical force acting on the strain sensing element (3) in real time. and lateral force The calculation formula is:

7. Among them: The output voltage of the bridge is used for vertical force measurement. The output voltage of the bridge for measuring lateral force. Where is Poisson's ratio, and K is the strain gauge sensitivity coefficient. u is the elastic modulus of the strain sensing element. s Supply voltage to the bridge circuit. This represents the transverse cross-sectional area of ​​the strain sensing element at the location of the strain gauge. This represents the flexural section modulus of the strain-sensing element at the location of the strain gauge. This is the distance from the center of the strain gauge to the upper connecting plate.

8. A method for monitoring the load characteristics of an electric loader during digging operations, characterized in that, The monitoring system applied to any one of claims 1-6 includes the following steps: S1. Install a load characteristic monitoring device at the location where the left side of the front axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the right side of the front axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the left side of the rear axle of the electric loader connects to the chassis of the electric loader. A load characteristic monitoring device is installed at the location where the rear axle of the electric loader connects to the chassis of the electric loader. During the arrangement process, ensure that the plane of all load characteristic monitoring device strain gauge assembly (4) is perpendicular to the longitudinal direction of the electric loader body; S2. When the electric loader is on a level surface and the bucket is off the ground and stationary, record the load characteristics using the monitoring device. Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement Load characteristic monitoring device Initial vertical force measurement The total mass loaded on the entire electric loader is... for: ,in, Represents gravitational acceleration; S3, Real-time measurement of four load characteristic monitoring devices , , , The vertical and lateral force values ​​are denoted as follows: , , , and , , , Vertical load experienced by an electric loader during bucket digging. and lateral load They are respectively: ， S4. During the material shoveling process, if , This is the eccentric load factor. The value range is 1.2~1.4, indicating that there is an off-center vertical load on the bucket of the electric loader during the material digging process, and the vertical load on the left side of the bucket is significantly greater than that on the right side; if This indicates that during the material scooping process of the electric loader bucket, there is an off-center vertical load phenomenon, and the vertical load on the right side of the bucket is significantly greater than that on the left side. S5. During the material shoveling process, if This indicates that there is an uneven lateral load on the bucket of the electric loader during the material scooping process, and the lateral load on the left side of the bucket is significantly greater than that on the right side; if This indicates that there is an uneven lateral load on the bucket of the electric loader during the material digging process, and the lateral load on the right side of the bucket is significantly greater than that on the left side. S6. During the material shoveling process, record... They are respectively The difference in vertical force at this moment compared to the previous monitoring moment. Let be the load mutation coefficient, if at a certain moment For positive negative and , The value range is 2.5~3, indicating that the bucket suddenly encountered a sudden change in vertical load at that moment, that is, the bucket encountered a large or hard material during the digging process. S7. After the material shoveling is completed and the machine remains stationary, the weight of the material shoveled by the electric loader can be calculated using the measured values ​​of the vertical force from the four load characteristic monitoring devices. The calculation formula is: ； S8. When lifting or lowering the bucket after the material shoveling process is completed, if Continued decline and A continuous rise indicates that the bucket is in the lifting phase; if Continuously increasing and The continued decline indicates that the bucket is in the lowering phase of the work.

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