Mining excavator overspeed protection device and method

Abstract

The invention provides an overspeed protection device and method for a mining excavator, the overspeed protection device for the mining excavator comprises a signal acquisition unit, a control unit and an execution unit, and a set of complete closed-loop protection system is constructed through cooperative operation of the signal acquisition unit, the control unit and the execution unit. The device can monitor the running states of the lifting mechanism and the pushing mechanism in real time, an emergency braking program is started immediately when the overspeed working condition is detected through accurate speed calculation and judgment logic, fundamental conversion from passive dependence on artificial experience to active intelligent protection is achieved, and the safety of the device is improved. The problem of out-of-control falling caused by electrical faults under the potential energy load condition is effectively solved, the reliability and safety of equipment operation are remarkably improved, and an important guarantee is provided for safe production of mines.

Description

Technical Field

[0001] This invention relates to the field of excavator technology, specifically to an overspeed protection device and method for mining excavators. Background Technology

[0002] With the continuous expansion of mining scale and increasingly stringent operational requirements, the operational safety and control reliability of electric shovel excavators, as key mining and loading equipment, are receiving increasing attention. During lifting and pressing operations, the potential energy load in electric shovels makes them susceptible to bucket slippage and fall due to electrical drive system malfunctions, potentially causing equipment damage or even accidents. Therefore, higher demands are placed on real-time detection of overspeed and rapid braking protection. Traditional electric shovel control systems lack real-time monitoring and closed-loop protection mechanisms for operating speed, relying solely on operator experience and emergency procedures, resulting in significant lag and human uncertainty.

[0003] The existing electric shovel control system has significant safety defects. Due to the lack of effective speed monitoring and automatic protection mechanisms, when the drive system fails, the potential energy load will cause the bucket to continuously accelerate and fall. Operators can only rely on their personal experience to judge whether the equipment is overspeeding and manually execute emergency braking. This protection method that relies on manual intervention has unavoidable response lag and judgment error, making it difficult to curb the occurrence of overspeed accidents in time, and exposing the equipment to major safety risks such as wire rope reversal, mechanism damage, or even the entire machine overturning.

[0004] Therefore, there is an urgent need for an overspeed protection device and method for mining excavators to solve the above-mentioned technical problems. Summary of the Invention

[0005] In view of the problems existing in the prior art, one of the objectives of the present invention is: In a first aspect, the present invention provides an overspeed protection device for a mining excavator, comprising: A signal acquisition unit is used to acquire the position signals of the lifting mechanism and / or pushing mechanism of the excavator in real time. The control unit is communicatively connected to the signal acquisition unit. The control unit is used to receive the position signal acquired by the signal acquisition unit, calculate the real-time operating speed of the mechanism based on the position signal, compare the real-time operating speed with a preset speed threshold, and generate an overspeed protection command when the real-time operating speed is greater than or equal to the speed threshold. An execution unit is communicatively connected to the control unit. The execution unit is used to receive the overspeed protection command to perform emergency braking on the lifting mechanism and / or pushing mechanism of the excavator.

[0006] In one embodiment, the signal acquisition unit is a multi-turn absolute encoder, the control unit is a programmable logic controller, the execution unit includes a frequency converter and a brake, and the programmable logic controller is used to perform differential calculations on the position signal acquired by the multi-turn absolute encoder to obtain the real-time operating speed.

[0007] In one embodiment, an overspeed switch is also included. The overspeed switch is connected to the drive shaft of the lifting mechanism and / or the pushing mechanism. The overspeed switch is electrically connected to the control unit. The overspeed switch is used to send a trigger signal to the control unit when the rotational speed of the drive shaft exceeds a preset value. The control unit can generate the overspeed protection command when it receives the trigger signal or when the real-time operating speed is determined to be overspeed.

[0008] In one embodiment, a protective component is also included, the protective component comprising a mounting base and a protective cover, the mounting base being fixed to the body of the excavator, the protective cover being able to enclose the mounting base to form a receiving cavity, the signal acquisition unit being fixed to the mounting base, and the signal acquisition unit being located within the receiving cavity.

[0009] In one embodiment, a human-machine interaction unit is also included. The human-machine interaction unit is communicatively connected to the control unit and is used to display the real-time operating speed, overspeed alarm information and encoder fault information in real time, and to receive and transmit fault reset commands input by the user.

[0010] Secondly, the present invention also provides an overspeed protection method for a mining excavator, applied to the aforementioned overspeed protection device, the method comprising: The position signals of the excavator's lifting mechanism and / or pushing mechanism are collected in real time. Calculate the real-time operating speed of the mechanism based on the position signal; The real-time operating speed is compared with a preset speed threshold; If the real-time operating speed is greater than or equal to the speed threshold, an overspeed protection command is generated; In response to the overspeed protection command, an emergency braking operation is performed on the lifting mechanism and the pushing mechanism.

[0011] In one embodiment, the step of calculating the real-time running speed based on the position signal includes: The control unit performs differential calculations on the position signals acquired by the signal acquisition unit to obtain the real-time operating speed.

[0012] In one implementation, it further includes: Perform fault diagnosis on the signal acquisition unit used to acquire position signals; When a fault is diagnosed in the signal acquisition unit, an alarm signal for the fault in the signal acquisition unit is generated.

[0013] In one embodiment, the step of performing emergency braking in response to an overspeed protection command includes: A setting command with a speed value of zero is issued to the drive unit, and braking torque is provided.

[0014] In one embodiment, after performing emergency braking, the method further includes: After the overspeed fault is cleared, receive the fault reset signal triggered by the user; In response to the fault reset signal, the excavator enters the start-up preparation state.

[0015] Compared with the prior art, the advantages of this invention are that the embodiments of this application provide an overspeed protection device and method for mining excavators. This overspeed protection device includes a signal acquisition unit, a control unit, and an execution unit. Through the coordinated operation of the signal acquisition unit, control unit, and execution unit, a complete closed-loop protection system is constructed. This device can monitor the operating status of the hoisting mechanism and the pushing mechanism in real time. Through precise speed calculation and judgment logic, it immediately initiates an emergency braking procedure when an overspeed condition is detected. This achieves a fundamental shift from passively relying on human experience to proactive intelligent protection, effectively solving the problem of uncontrolled descent caused by electrical faults under potential energy load conditions. It significantly improves the reliability and safety of equipment operation, providing important protection for safe mine production. Attached Figure Description Figure 1 This is a schematic diagram of the structure of an overspeed protection device for a mining excavator provided in some embodiments of this application.

[0016] Figure 2 A flowchart illustrating an overspeed protection method for a mining excavator, provided for some embodiments of this application.

[0017] Figure label: 1. Control unit; 2. Signal acquisition unit; 3. Cables; 4. Couplings; 5. Execution unit. Detailed Implementation

[0018] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0019] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0020] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0021] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or a joint; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0022] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0023] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0024] The invention will now be further described with reference to the accompanying drawings.

[0025] Firstly, see Figure 1 This application provides an embodiment of an overspeed protection device for a mining excavator. The overspeed protection device includes a signal acquisition unit 2, a control unit 1, and an execution unit. The signal acquisition unit 2 is used to acquire the position signals of the excavator's lifting mechanism and / or pushing mechanism in real time. The control unit 1 is communicatively connected to the signal acquisition unit 2 and is used to receive the position signals acquired by the signal acquisition unit 2. The control unit 1 calculates the real-time running speed of the mechanism based on the position signals and compares the real-time running speed with a preset speed threshold. When the real-time running speed is greater than or equal to the speed threshold, an overspeed protection command is generated. The execution unit is communicatively connected to the control unit 1 and is used to receive the overspeed protection command to perform emergency braking on the excavator's lifting mechanism and / or pushing mechanism.

[0026] The overspeed protection device for a mining excavator provided in this embodiment constructs a complete closed-loop protection system through the coordinated operation of the signal acquisition unit 2, the control unit 1, and the execution unit. This device can monitor the operating status of the hoisting and pushing mechanisms in real time. Through precise speed calculation and judgment logic, it immediately initiates an emergency braking procedure when an overspeed condition is detected. This achieves a fundamental shift from passively relying on human experience to proactive intelligent protection, effectively solving the problem of uncontrolled descent caused by electrical faults under potential energy load conditions. It significantly improves the reliability and safety of equipment operation, providing important protection for safe mine production.

[0027] In this embodiment of the application, the speed threshold is 115% of the maximum permissible operating speed of the lifting mechanism and / or the pushing mechanism.

[0028] The 15% figure here comes from engineering practice and is derived from specific working conditions such as the potential energy load characteristics of electric shovels, brake response time, and fluctuation patterns of operating load. It balances the "risk of false alarms" with the "timeliness of safety protection." If the speed exceeds the maximum permissible speed by 15%, it is difficult for the brake to achieve rapid braking due to the brake response time characteristics. Furthermore, the electric shovel operator can only clearly observe the speed exceeding the maximum permissible speed by 15%. Theoretically, this is a fixed value.

[0029] The embodiments of this application are mainly used for electric shovels driven by permanent magnet synchronous motors. The lifting mechanism of the electric shovel uses a permanent magnet synchronous motor, which is different from an asynchronous motor. Since its rotor is a permanent magnet, it will generate a back electromotive force when the rotor rotates. Under the action of potential energy load, the speed of the lifting and pushing motor will increase. Once the speed exceeds the limit, the generated back electromotive force will be very high, which will cause permanent damage to the equipment. Therefore, overspeed protection is very important.

[0030] like Figure 1 As shown, in some embodiments, the signal acquisition unit 2 is a multi-turn absolute encoder, the control unit 1 is a programmable logic controller, and the execution unit includes a frequency converter and a brake. The programmable logic controller is used to perform differential calculations on the position signals acquired by the multi-turn absolute encoder to obtain the real-time running speed.

[0031] By employing a multi-turn absolute encoder as the signal acquisition unit 2, a programmable logic controller (PLC) as the control unit 1, and combining a frequency converter and a brake to form the execution unit, a highly efficient and reliable overspeed protection system was constructed. This system can fully utilize existing equipment hardware and perform real-time differential calculations on the position signals acquired by the encoder through the PLC to accurately obtain the instantaneous operating speed of the mechanism. It not only realizes continuous monitoring of the operating status of the lifting and pushing mechanisms, but also achieves rapid and accurate emergency braking through the coordinated action of the frequency converter and the brake when overspeed is detected. This effectively solves the safety hazards caused by the lack of automatic protection when the drive system of a traditional electric shovel fails, and significantly improves the safety performance and operational reliability of the equipment.

[0032] In this embodiment of the application, the programmable logic controller is also referred to as a PLC (Programmable Logic Controller).

[0033] In this embodiment, the multi-turn absolute encoder is connected to the drum of the lifting mechanism or the drive shaft of the pressing mechanism via a coupling 4, and the programmable logic controller is connected to the multi-turn absolute encoder via a cable 3.

[0034] like Figure 1 As shown, in some embodiments, an overspeed switch is also included. The overspeed switch is connected to the drive shaft of the lifting mechanism and / or the pushing mechanism. The overspeed switch is electrically connected to the control unit 1. The overspeed switch is used to send a trigger signal to the control unit 1 when the rotational speed of the drive shaft exceeds a preset value. The control unit 1 can generate an overspeed protection command when it receives the trigger signal or when the real-time running speed is determined to be overspeed.

[0035] By adding a mechanical overspeed switch directly connected to the drive shaft, a redundant protection architecture is formed together with the encoder-based electrical detection system. This creates a dual-path protection mechanism that combines electrical detection and mechanical triggering. When any detection channel detects an overspeed condition, it can independently trigger a protection command, effectively avoiding protection failures caused by encoder malfunctions, signal interference, or control system anomalies. This significantly improves the reliability and safety of the system, ensuring reliable overspeed protection even under extreme conditions, and providing multiple safeguards for the safe operation of large mining equipment.

[0036] like Figure 1 As shown, in some embodiments, a protective component is also included. The protective component includes a mounting base and a protective cover. The mounting base is fixed to the body of the excavator, and the protective cover can be enclosed with the mounting base to form a receiving cavity. The signal acquisition unit 2 is fixed to the mounting base and is located inside the receiving cavity.

[0037] By setting up a dedicated protective assembly consisting of a mounting base and a protective cover, the signal acquisition unit 2 is provided with all-round protection. The sealed cavity formed by the protective cover and the mounting base can effectively block common pollutants such as dust, moisture, and oil in the mining site, while resisting vibration and mechanical damage during operation. This significantly improves the environmental adaptability of precision measuring equipment such as multi-turn absolute encoders under harsh working conditions, ensuring that they maintain accurate measurement performance and stable signal output for a long time. From the hardware foundation, this guarantees the accuracy of the monitoring data of the overspeed protection system and the operational reliability of the entire protection system.

[0038] like Figure 1 As shown, in some embodiments, a human-machine interaction unit is also included. The human-machine interaction unit is communicatively connected to the control unit 1 and is used to display real-time operating speed, overspeed alarm information and encoder fault information, and to receive and transmit fault reset commands input by the user.

[0039] By adding a human-machine interaction unit, a comprehensive management platform integrating status monitoring, fault alarm, and system reset was constructed. The human-machine interaction unit can display the mechanism's operating speed, overspeed alarm status, and sensor fault information in real time, providing operators with a comprehensive and intuitive display of equipment operating conditions. At the same time, by receiving and transmitting fault reset commands, the protection system achieves complete closed-loop management from alarm, processing to recovery, thereby significantly improving the system's operability and maintenance convenience. The transparency of equipment operating status and the manageability of the system have been comprehensively improved, providing effective decision support for on-site operators.

[0040] In some embodiments, the execution unit further includes an emergency braking relay independent of the programmable logic controller. The coil circuit of the emergency braking relay is controlled by the overspeed protection command output by the programmable logic controller, and the emergency braking relay is connected in series in the power supply circuit of the brake.

[0041] By adding an emergency braking relay independent of the programmable logic controller (PLC), a safety redundancy protection is constructed. The coil of this relay is controlled by the PLC, while its contacts are directly connected in series in the brake power supply circuit, forming an independent hard-wired safety channel. This ensures that even if the PLC system experiences a program abnormality or communication failure, it can still directly trigger the brake action through the hardware circuit once an overspeed protection command is received. This effectively avoids protection failure caused by soft faults in the control system, significantly improves the reliability and safety of the entire overspeed protection system, and provides a more reliable final safety guarantee for the equipment.

[0042] Secondly, see Figure 2 This application provides an embodiment of a method for overspeed protection of a mining excavator, applied to the aforementioned overspeed protection device. The method includes: Real-time acquisition of position signals from the excavator's lifting mechanism and / or pushing mechanism; The real-time operating speed of the calculation mechanism is determined based on the position signal; Compare the real-time running speed with the preset speed threshold; If the real-time operating speed is greater than or equal to the speed threshold, an overspeed protection command will be generated. In response to the overspeed protection command, an emergency braking operation is performed on the lifting mechanism and the pushing mechanism.

[0043] The overspeed protection method for mining excavators provided in this application embodiment establishes a dynamic monitoring mechanism that integrates real-time position acquisition, speed calculation, and threshold comparison. This mechanism enables precise perception and rapid response to the operating status of the lifting and pushing mechanisms. The method can immediately trigger an emergency braking command when an overspeed condition is detected, forming a complete protection closed loop from status monitoring and risk identification to proactive intervention. This method overcomes the limitations of traditional methods that rely on manual experience and judgment, significantly improves the autonomous safety protection capability of equipment under sudden situations such as electrical faults, effectively curbs major equipment accidents that may be caused by potential energy load runaway, and provides advanced and reliable technical support for the safe operation of large mining equipment.

[0044] like Figure 1 As shown, in some embodiments, the step of calculating the real-time running speed based on the position signal includes: The control unit 1 performs differential calculations on the position signals acquired by the signal acquisition unit 2 to obtain the real-time running speed.

[0045] By performing real-time differential calculations on the position signal through control unit 1, a precise conversion from displacement to velocity is achieved. This velocity calculation method based on the differential principle can keenly capture the instantaneous changes in the operating state of the mechanism, providing accurate and timely data for overspeed judgment. It fully utilizes the computing potential of the existing control system and achieves precise dynamic monitoring of the equipment's operating status without adding dedicated speed measurement hardware. This not only reduces system costs but also significantly improves the response speed and judgment reliability of overspeed protection.

[0046] like Figure 2 As shown, in some embodiments, it also includes: Perform fault diagnosis on signal acquisition unit 2 used to acquire position signals; When a fault is diagnosed in signal acquisition unit 2, an alarm signal for the fault in signal acquisition unit 2 is generated.

[0047] By adding a real-time fault diagnosis mechanism for signal acquisition unit 2, a complete system self-monitoring system was constructed. This solution can continuously monitor the working status of key sensing components such as encoders, and immediately trigger an alarm when abnormal signals or equipment failures are detected, effectively avoiding blind spots in protection functions caused by sensor failure. This design significantly improves the reliability and safety of the overspeed protection system, ensuring that the system can still provide timely status warnings and maintenance guidance when core detection components fail, providing dual protection for the continuous safe operation and rapid repair of the equipment.

[0048] like Figure 2 As shown, in some embodiments, the step of performing emergency braking in response to an overspeed protection command includes: It issues a setting command with a speed value of zero to the drive execution unit and provides braking torque.

[0049] By issuing a zero-speed command to the drive system and simultaneously applying mechanical braking torque, the synergistic effect of electrical control and mechanical braking is achieved. This enables the simultaneous activation of dual braking upon detecting overspeed. On the one hand, the power output is cut off and a zero-speed target is set through the electrical system; on the other hand, reliable braking torque is provided through the mechanical brake. This composite braking strategy effectively overcomes the limitations of single braking methods, such as response lag or insufficient torque. It significantly improves the response speed and braking efficiency of the braking system, ensuring that the equipment can quickly and smoothly achieve safe shutdown under overspeed conditions, providing a more reliable safety guarantee for large mining equipment.

[0050] like Figure 2 As shown, in some embodiments, after performing the emergency braking operation, the method further includes: After the overspeed fault is cleared, receive the fault reset signal triggered by the user; In response to the fault reset signal, the excavator enters the start-up preparation state.

[0051] This embodiment constructs a complete closed-loop protection process by setting up fault reset and system recovery mechanisms. This scheme requires that after emergency braking, the system can only re-enter the start-up preparation state after the operator confirms that the fault has been cleared and actively issues a reset command. This ensures that every overspeed fault can be effectively handled and confirmed, and also gives the operator the final decision-making power over the equipment's resumption of operation. It effectively prevents the system from being accidentally started before the safety hazards are completely eliminated, significantly improves the safety and standardization of equipment management, and realizes the organic combination of automatic protection and manual supervision.

[0052] In this embodiment, the brake opening sequence is as follows: the lifting mechanism and / or the pushing mechanism receive the driver's brake opening ("brake release") command, the frequency converter starts first, establishes a torque that is balanced with the load, and after a system delay of t1 (2 seconds), the programmable logic controller outputs the "brake open" command, and after the solenoid valve controlling the brake action is activated, the disc brake opens.

[0053] In this embodiment, the brake closing sequence is as follows: a brake closing command is issued, the brake is reset, the motor continues to output torque, and the stationary state of the lifting mechanism and / or the pushing mechanism is achieved by the braking torque output by the motor and the braking torque provided by the brake. After t2 (3 seconds), the motor is de-energized, the motor no longer provides braking torque, and the stationary state of the lifting mechanism and / or the pushing mechanism is achieved by the braking torque provided by the brake.

[0054] In this embodiment, the programmable logic controller reads the position signal and performs differential processing on the time to obtain the current speed: v=dx / dt.

[0055] For example, if the mechanism travels 2 meters in 0.1 seconds, then its speed is 20 meters per second. The calculation process is performed in the programmable logic controller.

[0056] In addition, in this application embodiment, the electric shovel can be stopped in two ways: normal stop and fault stop. Fault stop is further divided into fault delayed stop and fault emergency stop. The electric shovel can only enter the start-up preparation state after the fault is cleared and the driver presses the fault reset button.

[0057] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An overspeed protection device for mining excavators, characterized in that, include: A signal acquisition unit is used to acquire the position signals of the lifting mechanism and / or pushing mechanism of the excavator in real time. The control unit is communicatively connected to the signal acquisition unit. The control unit is used to receive the position signal acquired by the signal acquisition unit, calculate the real-time operating speed of the mechanism based on the position signal, compare the real-time operating speed with a preset speed threshold, and generate an overspeed protection command when the real-time operating speed is greater than or equal to the speed threshold. An execution unit is communicatively connected to the control unit. The execution unit is used to receive the overspeed protection command to perform emergency braking on the lifting mechanism and / or pushing mechanism of the excavator.

2. The overspeed protection device for mining excavators according to claim 1, characterized in that, The signal acquisition unit is a multi-turn absolute encoder, the control unit is a programmable logic controller, and the execution unit includes a frequency converter and a brake. The programmable logic controller is used to perform differential calculations on the position signals acquired by the multi-turn absolute encoder to obtain the real-time operating speed.

3. The overspeed protection device for mining excavators according to claim 1, characterized in that, It also includes an overspeed switch, which is connected to the drive shaft of the lifting mechanism and / or the pushing mechanism. The overspeed switch is electrically connected to the control unit. The overspeed switch is used to send a trigger signal to the control unit when the rotational speed of the drive shaft exceeds a preset value. The control unit can generate the overspeed protection command when it receives the trigger signal or when the real-time operating speed is determined to be overspeed.

4. The overspeed protection device for mining excavators according to claim 1, characterized in that, It also includes a protective component, which includes a mounting base and a protective cover. The mounting base is fixed to the body of the excavator, and the protective cover can be enclosed with the mounting base to form a receiving cavity. The signal acquisition unit is fixed to the mounting base and is located inside the receiving cavity.

5. The overspeed protection device for mining excavators according to claim 1, characterized in that, It also includes a human-machine interaction unit, which is communicatively connected to the control unit and is used to display the real-time operating speed, overspeed alarm information and encoder fault information in real time, and to receive and transmit fault reset commands input by the user.

6. A method for overspeed protection of mining excavators, characterized in that, The method, applied to the overspeed protection device as described in any one of claims 1-5, comprises: The position signals of the excavator's lifting mechanism and / or pushing mechanism are collected in real time. Calculate the real-time operating speed of the mechanism based on the position signal; The real-time operating speed is compared with a preset speed threshold; If the real-time operating speed is greater than or equal to the speed threshold, an overspeed protection command is generated; In response to the overspeed protection command, an emergency braking operation is performed on the lifting mechanism and the pushing mechanism.

7. The overspeed protection method for mining excavators according to claim 6, characterized in that, The step of calculating the real-time operating speed based on the position signal includes: The control unit performs differential calculations on the position signals acquired by the signal acquisition unit to obtain the real-time operating speed.

8. The overspeed protection method for mining excavators according to claim 6, characterized in that, Also includes: Perform fault diagnosis on the signal acquisition unit used to acquire position signals; When a fault is diagnosed in the signal acquisition unit, an alarm signal for the fault in the signal acquisition unit is generated.

9. The overspeed protection method for mining excavators according to claim 6, characterized in that, The steps of performing emergency braking in response to an overspeed protection command include: A setting command with a speed value of zero is issued to the drive unit, and braking torque is provided.

10. The overspeed protection method for mining excavators according to claim 6, characterized in that, After performing emergency braking, the method further includes: After the overspeed fault is cleared, receive the fault reset signal triggered by the user; In response to the fault reset signal, the excavator enters the start-up preparation state.

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