Automatic ladder stand control system suitable for ultra-large excavator

Abstract

The invention provides an automatic ladder stand control system suitable for an ultra-large excavator, which relates to the technical field of engineering machinery and comprises a limit switch self-checking device and a controller, the limit switch self-checking device comprises a current driving unit, a signal checking unit and a self-checking judgment unit. The controller is connected with the limit switch self-checking device and executes the following operations according to the output of the self-checking judgment unit: if the crawling ladder ascends or descends, the self-checking judgment unit outputs an effective trigger signal to prohibit the crawling ladder from continuing to ascend or descend; if the self-checking judgment unit outputs a false triggering signal in the ascending process of the crawling ladder, a segmented ascending mode is started; if the self-checking judgment unit outputs a false triggering signal in the descending process of the crawling ladder, continuous descending is allowed. According to the invention, the current driving unit outputs the pulse verification current, the signal verification unit monitors the level fluctuation, and the self-check determination unit dynamically distinguishes the effective / false trigger signal based on the noise margin threshold, thereby improving the reliability of the automatic ladder stand control system.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering machinery, and in particular to an automatic ladder climbing control system suitable for an ultra-large excavator. Background Art

[0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art.

[0003] Ultra-large excavators require automatic ladders for boarding due to their high crawler tracks. The inventors discovered that existing ladder control systems have the following significant drawbacks: (1) The existing ladder control system relies on the safety handle to be closed before the ladder can be operated. If the driver does not close the handle after the operation, the ladder cannot be retracted or extended. Since the safety handle includes multiple switches or buttons such as the retract proximity switch, the extend proximity switch, and the unlock proximity switch, it is cumbersome to close all the safety handles. (2) The existing ladder control system uses a dual controller + surround view system to detect obstacles, which is expensive and does not solve the problem of false triggering of switches. During the descent of the ladder, it only relies on the camera to determine the ground height. If the control switch fails, the ladder is easily damaged by the long-term pressure overflow, posing a safety hazard. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention outputs a pulse verification current through a current driving unit, monitors the level fluctuation by a signal verification unit, and a self-detection judgment unit dynamically distinguishes between valid / false trigger signals based on a noise tolerance threshold, thereby improving the reliability of the automatic ladder control system.

[0005] A first aspect of the present invention provides an automatic ladder control system suitable for an ultra-large excavator, comprising: a limit switch self-test device (11) and a controller (12); The limit switch self-test device is arranged at the ascending end point and the descending end point of the ladder, comprising: a current driving unit (111) for outputting a test current in response to a controller instruction; a signal test unit (112) for real-time monitoring the level fluctuation of the trigger signal during the output of the test current; a self-test determination unit (113) for outputting a valid trigger signal if the level fluctuation amplitude is less than or equal to a threshold value; and outputting a false trigger signal if the level fluctuation amplitude is greater than or equal to the threshold value. The controller (12) is connected to the limit switch self-test device (11) and is configured to: send a verification instruction to the current driving unit (111) when receiving a ladder action signal; receive a monitoring result from the signal verification unit (112) and determine the trigger validity; The controller (12) selectively performs the following operations according to the output of the self-checking and judging unit (113): if the ladder is in the process of ascending or descending, the self-checking and judging unit (113) outputs a valid trigger signal to prohibit the ladder from continuing to ascend or descend; if the ladder is in the process of ascending, the self-checking and judging unit (113) outputs a false trigger signal to start the segmented ascending mode; if the ladder is in the process of descending, the self-checking and judging unit (113) outputs a false trigger signal to shield the limit signal and allow the ladder to continue to descend.

[0006] Furthermore, the segmented ascending mode includes: In response to the continuous pressing signal of the rising switch, a segmented rising pulse instruction is generated in units of a preset safety time length; After each segmented rise is completed, it is necessary to detect the release state of the rise switch and re-trigger it to start the next rise cycle.

[0007] Furthermore, the controller (12) further comprises: a safety verification unit (121) for verifying multiple levels of safety conditions when performing a ladder descent operation, including: the engine is not started, the pilot switch is not turned on, the ladder descent limit switch is not turned on, and the ladder prohibition action button is not triggered.

[0008] Furthermore, the ladder prohibition action button is arranged at the ladder guardrail and is connected to the controller (12); when the ladder prohibition action button is triggered, a global interrupt signal is sent to the controller (12) to forcibly terminate all driving instructions.

[0009] Furthermore, the controller (12) further comprises: a ladder ascending stage protection unit (122), which outputs an alarm signal and locks the vehicle hydraulic valve when it detects that the pilot switch is turned on and the ladder ascending limit self-test result is not triggered or is triggered by mistake.

[0010] Furthermore, the controller (12) further comprises: a ladder descent stage protection unit (123); when the ladder descent limit self-check result is effectively triggered, the controller (12) outputs a descent oil circuit interruption instruction to the hydraulic valve group, driving the locking mechanism to fix the current position of the ladder.

[0011] A second aspect of the present invention provides an automatic ladder climbing control method applicable to an ultra-large excavator, comprising the following steps: Obtaining a ladder climbing action request signal, including an ascending instruction or a descending instruction; Based on the rising instruction or the falling instruction, outputting a pulse calibration current to the limit switch self-test device at the corresponding end point; Acquire the trigger signal level fluctuation data during the calibration current output period; generating a valid trigger or false trigger determination signal based on a comparison result of the fluctuation data and a preset noise tolerance threshold; When the judgment signal is triggered effectively: if the ladder is in the ascending stage, the ladder is prohibited from continuing to ascend; if the ladder is in the descending stage, the ladder stops descending and outputs a mechanical locking signal; When the signal is determined to be falsely triggered: if the ladder is in the ascending stage, the ladder ascends in sections; if the ladder is in the descending stage, the ladder continues to descend.

[0012] A third aspect of the present invention provides an ultra-large excavator, comprising: a vehicle body, a hydraulically driven liftable ladder, and the automatic ladder control system suitable for an ultra-large excavator.

[0013] A fourth aspect of the present invention provides a computer-readable storage medium storing program instructions, which, when executed by a processor, implement the steps of the above-mentioned automatic ladder climbing control method applicable to an ultra-large excavator.

[0014] A fifth aspect of the present invention provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of the above-mentioned automatic ladder climbing control method applicable to an ultra-large excavator.

[0015] Compared with the prior art, the automatic ladder control system for ultra-large excavators provided by the present invention has the following beneficial effects: (1) In response to the technical problem mentioned in the background art that all safety handles must be closed before ladder control can be performed, which is cumbersome to operate, the present invention provides a limit switch self-test device. The current driving unit in the limit switch self-test device outputs a pulse verification current, the signal verification unit monitors the level fluctuation, and the self-test judgment unit dynamically distinguishes between valid and false trigger signals based on the noise tolerance threshold, thereby realizing dynamic level fluctuation detection, improving the reliability of the automatic ladder control system, and simplifying the operation; (2) In response to the technical problem mentioned in the background art that if the control switch fails, the ladder will be damaged due to the long-term pressure overflow, which poses a safety hazard, the present invention provides a controller fault adaptive mechanism, including: starting the segmented rising mode when the rising limit is falsely triggered, and shielding the signal from continuing to fall when the falling limit is falsely triggered, so as to ensure that the ladder can be safely retracted and extended in the fault state; (3) The present invention also provides a vehicle linkage protection mechanism. The controller-based ladder ascending stage protection unit forcibly locks the hydraulic system when the pilot switch is turned on and the ladder is not retracted, thereby avoiding safety risks caused by the driver forgetting to retract the ladder and directly proceeding with the operation. (4) The present invention also provides a ladder prohibition action button, which is connected to the controller. The staff on the ladder can interrupt the response of various operation instructions of the super-large loader by pressing the ladder prohibition action button, thereby ensuring the personal safety of the staff on the ladder. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which constitute a part of the present disclosure, are used to provide a further understanding of the present disclosure. The exemplary embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation to the present disclosure.

[0017] Figure 1 This is a framework diagram of an automatic ladder control system for an ultra-large excavator provided in the first embodiment of the present invention; Figure 2 A flowchart of the steps of the ladder ascending or descending operation in the automatic ladder control method for a super-large excavator provided in the second embodiment of the present invention; Figure 3 This is a flow chart of the safety management steps in the automatic ladder control method for ultra-large excavators provided in the second embodiment of the present invention. DETAILED DESCRIPTION

[0018] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0019] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0020] In the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0021] All data in this embodiment is obtained in compliance with laws and regulations and based on the consent of the user, and is used legally.

[0022] Example 1 like Figure 1 , this embodiment provides an automatic ladder control system suitable for an ultra-large excavator, comprising: a limit switch self-test device (11) and a controller (12); The limit switch self-test device is arranged at the ascending end point and the descending end point of the ladder, comprising: a current driving unit (111) for outputting a test current in response to a controller instruction; a signal test unit (112) for real-time monitoring the level fluctuation of the trigger signal during the output of the test current; a self-test determination unit (113) for outputting a valid trigger signal if the level fluctuation amplitude is less than or equal to a threshold value; and outputting a false trigger signal if the level fluctuation amplitude is greater than or equal to the threshold value. The controller (12) is connected to the limit switch self-test device (11) and is configured to: send a verification instruction to the current driving unit (111) when receiving a ladder action signal; receive a monitoring result from the signal verification unit (112) and determine the trigger validity; The controller (12) selectively performs the following operations according to the output of the self-checking and judging unit (113): if the ladder is in the process of ascending or descending, the self-checking and judging unit (113) outputs a valid trigger signal to prohibit the ladder from continuing to ascend or descend; if the ladder is in the process of ascending, the self-checking and judging unit (113) outputs a false trigger signal to start the segmented ascending mode; if the ladder is in the process of descending, the self-checking and judging unit (113) outputs a false trigger signal to shield the limit signal and allow the ladder to continue to descend.

[0023] In a specific embodiment, when the controller (12) receives a ladder climbing action signal (ascending / descending), it sends a verification instruction to the limit switch self-test device (11), the current driving unit (111) outputs a pulse verification current, the signal verification unit (112) monitors the trigger signal level fluctuation in real time, and the self-test judgment unit (113) compares the fluctuation amplitude with a preset threshold: if the fluctuation is less than or equal to the threshold, a "valid trigger" signal is output (the switch is normally triggered), and the controller prohibits the ladder from continuing to move; if the fluctuation is greater than the threshold, a "false trigger" signal is output (the switch is faulty), and the controller starts a segmented ascent (when ascending) or blocks the signal from continuing to descend (when descending). By analyzing the pulse current excitation and level fluctuation, a true trigger and electromagnetic interference (such as the strong magnetic field of mining equipment) can be effectively distinguished, solving the problem of high false alarm rate of traditional proximity switches.

[0024] Specifically, the segmented ascent mode includes: In response to the continuous pressing signal of the rising switch, a segmented rising pulse instruction is generated in units of a preset safety time length; After each segmented rise is completed, it is necessary to detect the release state of the rise switch and re-trigger it to start the next rise cycle.

[0025] In one specific embodiment, a controller detects a continuous press signal from the rise switch, activates a segmented timer, generates a single rise pulse of a maximum "preset safety duration," and then the hydraulic cylinder drives the ladder upward. The ladder automatically stops when the timer expires. The next rise cycle can only be initiated after the switch is fully released and pressed again. This single rise time limit (e.g., 3 seconds) prevents prolonged pressure buildup in the oil circuit, preventing overheating and damage to the relief valve, extending the life of the hydraulic components by three times compared to an unprotected solution. A mandatory switch release reset eliminates the risk of continued ladder ascent due to a stuck switch. Even if the limit switch completely fails, the ladder can still be fully retracted through manual inching, resolving the technical issues inherent in the existing fail-safe mechanism.

[0026] Specifically, the controller (12) further comprises: a safety verification unit (121) for verifying multiple levels of safety conditions when performing a ladder descent operation, including: the engine is not started, the pilot switch is not turned on, the ladder descent limit switch is not turned on, and the ladder prohibition action button is not triggered.

[0027] In one specific embodiment, before the ladder descends, the controller verifies four conditions: (1) the engine status signal is "off"; (2) the pilot switch signal is "off" (the hydraulic pilot oil circuit is disconnected); (3) the descent limit self-test result is "not triggered"; and (4) there is no trigger signal from the inhibit action button. Only when all conditions are met is the descent drive command output. This invention incorporates the engine status into the ladder control chain for the first time, eliminating the risk of accidentally lowering the ladder during operation from the power source. The pilot switch status verification ensures that descent is allowed only after the operator leaves the driver's seat. The four conditions are verified in parallel to form redundant protection, and actual tests have shown that all accidental descent operations can be intercepted in practice.

[0028] Specifically, the ladder prohibition action button is arranged at the ladder guardrail and is connected to the controller (12); when the ladder prohibition action button is triggered, a global interrupt signal is sent to the controller (12) to forcibly terminate all driving instructions.

[0029] In a specific embodiment, an emergency stop button is located at the ladder guardrail, which is directly connected to the controller (12) by a hard wire. When triggered, a high-priority global interrupt signal is sent to the controller. The controller immediately terminates all hydraulic solenoid valve drive currents. The ladder and the entire vehicle are locked within 50ms. This eliminates the risk of crushing caused by miscommunication in multi-person collaboration scenarios (e.g., when maintenance is carried out with personnel in both the cab and the ladder).

[0030] Specifically, the controller (12) further comprises: a ladder ascending stage protection unit (122), which outputs an alarm signal and locks the vehicle hydraulic valve when it detects that the pilot switch is turned on and the ladder ascending limit self-test result is not triggered or is falsely triggered.

[0031] In one specific embodiment, the pilot switch status is monitored in real time. When the pilot switch is turned on (the operator is ready to operate), the ladder's up limit self-test result is immediately obtained. If the result is "not triggered" or "falsely triggered" (the ladder is not retracted), a hardware-level signal is directly output: the vehicle's hydraulic main valve solenoid is locked; and the cab's audible and visual alarm (fast flashing red light and a long beeping buzzer) is activated. This hydraulic valve lock mechanically prohibits vehicle movement, providing a higher safety factor than an alarm-only solution and resolving the technical problem of the driver forgetting to retract the ladder.

[0032] Specifically, the controller (12) further includes a ladder descent stage protection unit (123). When the ladder descent limit self-test result is effectively triggered, the controller (12) outputs a descent oil circuit interruption instruction to the hydraulic valve group, driving the locking mechanism to fix the current position of the ladder.

[0033] In a specific embodiment, when the descent limit self-check is "effectively triggered" (the ladder has been lowered to the limit position), the controller outputs a 0V power-off command to the descent oil circuit solenoid valve, cutting off the hydraulic oil supply; synchronously drives the locking solenoid valve (8), engaging the ladder mechanical buckle; and sends a motion prohibition command to the vehicle controller via the CAN bus. This achieves triple redundancy protection: (1) preventing damage to the oil cylinder due to pressure buildup; (2) physically fixing the ladder position; and (3) prohibiting rotation / travel that would cause pulling.

[0034] Example 2 like Figure 2 This embodiment provides an automatic ladder climbing control method applicable to a super-large excavator, comprising the following steps: Obtaining a ladder climbing action request signal, including an ascending instruction or a descending instruction; Based on the rising instruction or the falling instruction, outputting a pulse calibration current to the limit switch self-test device at the corresponding end point; Acquire the trigger signal level fluctuation data during the calibration current output period; generating a valid trigger or false trigger determination signal based on a comparison result of the fluctuation data and a preset noise tolerance threshold; When the judgment signal is triggered effectively: if the ladder is in the ascending stage, the ladder is prohibited from continuing to ascend; if the ladder is in the descending stage, the ladder stops descending and outputs a mechanical locking signal; When the signal is determined to be falsely triggered: if the ladder is in the ascending stage, the ladder ascends in sections; if the ladder is in the descending stage, the ladder continues to descend.

[0035] A limit switch self-test device is installed at the end position of the ladder's ascent and descent, which includes the functions of a traditional limit switch. At the same time, the controller can determine whether the limit switch function is normal based on the limit switch inspection method.

[0036] Specifically, the limit switch inspection method is as follows: when the controller receives a position signal trigger sent by the limit switch self-test device, it outputs a control current to the limit switch self-test device, drives the internal mechanical structure of the limit switch self-test device to verify whether the position signal is normally triggered or falsely triggered. During the period when the controller outputs current, if the position signal does not change, it indicates normal triggering; if there is a change, it indicates that the limit switch is abnormal.

[0037] A prohibition action button is installed on the ladder. When a driver stands on the ladder, pressing the prohibition action button will prohibit any action to ensure the safety of personnel.

[0038] When the ladder ascending action switch is pressed, the ladder ascending limit switch must not be triggered, and the prohibition action button on the ladder must not be triggered. The ladder can ascend. If the ladder ascending limit switch is triggered, the limit switch test is performed. If the test passes, it means that the ladder has reached the limit position. To protect the ladder system and prevent long-term pressure accumulation and overflow, the ladder is prohibited from ascending.

[0039] When the ladder up limit switch is triggered but the test fails, in order to ensure the normal operation of the excavator, the driver can continue to press the ladder up switch. Each time the switch is pressed, the ladder will rise for a maximum of 3 seconds. Repeat the operation to completely retract the ladder.

[0040] When the ladder descending switch is pressed, the ladder can descend only when the engine is not started, the pilot switch is not turned on, the ladder descending limit switch is not turned on, and the ladder prohibition action button is not triggered. If the ladder descending limit switch is triggered, the limit switch test is performed. If it fails, the descending limit switch signal is blocked.

[0041] like Figure 3 The automatic ladder climbing control method for a super-large excavator provided in this embodiment further includes the following steps: Get the pilot switch status signal; Based on the logical AND operation result of the pilot switch status signal and the ladder ascending limit judgment signal: when the pilot switch is turned on and the ascending limit is not triggered or is mistakenly triggered, the vehicle hydraulic locking signal and the alarm triggering signal are output; Obtain the trigger signal of the ladder prohibition action button and interrupt all drive command outputs based on the signal.

[0042] Specifically, after the vehicle is powered on, when the pilot rod is lowered, a judgment is made. If the ladder descending action switch is triggered, an alarm will be issued to remind the driver not to lower the ladder to ensure personal safety; if the ladder ascending limit switch is not triggered, an alarm will be issued to remind the driver to retract the spiral ladder, and the controller will prohibit the vehicle from moving. If the ladder ascending limit switch fails the inspection and is in a false triggering state, an alarm will also be issued and the vehicle will be prohibited from moving.

[0043] The pilot switch is an enabling switch located at the joystick, which is used to detect the operator's operating status and control the on-off of the hydraulic pilot oil circuit.

[0044] In a specific embodiment, the automatic ladder climbing control method applicable to an ultra-large excavator is as follows: Step S1: Ladder climbing operation S101: The worker continuously presses the up switch in the cab; S102: The controller detects an upward signal and actively triggers the upward limit switch self-test: a pulse calibration current is sent to the upward end limit switch; signal fluctuations during the current output are monitored; if the fluctuation is ≤ the noise tolerance threshold, it is determined to be a valid trigger; if the fluctuation is greater than the threshold, it is determined to be a false trigger; S103: If the self-test result is a valid trigger, climbing the ladder is prohibited and an audible and visual alarm is triggered; S104: If the self-test result is a false trigger, the segmented ascent mode is activated: during a single continuous press, the ascent time of the ladder is ≤ the preset safety time (for example, 3 seconds); after releasing the ascent switch, it is necessary to press it again to start the next ascent action; S105: Repeat the stepwise ascent until the ladder is completely retracted.

[0045] Step S2: Ladder descending operation S201: The staff presses the descending switch; S202: The controller verifies the multi-level safety conditions: whether the engine is turned off; whether the pilot switch is not turned on; whether the lowering limit switch is not effectively triggered; whether the ladder prohibition action button is not triggered; S203: If all conditions are met, trigger the descending limit switch self-test (same as S102 process); S204: If the self-test result is a false trigger, the limit signal is shielded and the ladder is driven down; S205: If the self-test result is a valid trigger, the descent is immediately terminated and the mechanical lock is activated.

[0046] Step S3: Vehicle safety interception S301: When the worker turns on the pilot switch to prepare for operation; S302: The controller detects the ladder ascending limit status: if it is not triggered or is triggered by mistake, it is determined that the ladder is not safely retracted; S303: Outputting a vehicle hydraulic locking command to forcibly prohibit all movements of the excavator; S304: Synchronously trigger the cab sound and light alarm, prompting "Please fold up the ladder".

[0047] Step S4: Emergency stop S401: A worker triggers the prohibition action button on the ladder; S402: The controller immediately interrupts all ladder climbing and vehicle driving instructions.

[0048] When there are many people at the excavator site, some will be standing on the ladder and some in the cab. The people standing on the ladder need to ensure their own safety, so a prohibition action switch is set. When the person on the ladder presses it, the entire vehicle cannot move, thus avoiding safety accidents caused by negligent operation of the excavator by the people in the cab.

[0049] The ideal state for lowering the ladder is when the excavator cannot move. Therefore, only when the engine is started and the pilot rod is opened, and the excavator meets the sufficient conditions for movement, is it prohibited to lower the ladder.

[0050] When the ladder reaches its full height, it should stop rising immediately to protect the power system. However, if a problem occurs with the limit switch, in order to ensure that the spiral ladder can be retracted smoothly, the ladder will be allowed to rise for a preset safety time (for example, 3 seconds) each time while the switch is pressed continuously. This allows the driver to retract the ladder and protect the power system of the ladder.

[0051] Example 3 This embodiment provides an ultra-large excavator, comprising: a vehicle body, a hydraulically driven elevating ladder, and an automatic ladder control system for ultra-large excavators provided in Example 1. Ultra-large excavators are excavators with specifications exceeding 200 tons, such as the Lovol FR2000F.

[0052] Example 4 This embodiment provides a computer-readable storage medium storing program instructions. When the program instructions are executed by a processor, the steps of the automatic ladder control method applicable to a super-large excavator provided in the second embodiment are implemented.

[0053] The computer-readable storage medium may be any medium capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk. The stored program instructions include a data acquisition program, a data preprocessing program, a multi-source data fusion program, a dynamic weight adjustment program, a calibration result calculation program, and a feedback execution program. When executed by a processor, these program instructions implement all steps of the automatic ladder climbing control method for an ultra-large excavator described in the present invention.

[0054] Example 5 This embodiment provides a computer program product, including a computer program. When the computer program is executed by a processor, the computer program implements the steps of the automatic ladder control method applicable to an ultra-large excavator provided in the second embodiment.

[0055] In the above embodiments of the present invention, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0056] In the several embodiments provided by the present invention, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are merely illustrative. For example, the division of the above-mentioned units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, and can be electrical or other forms.

[0057] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0058] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0059] If the above-mentioned integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes instructions for causing a computer device (such as a personal computer, server, or network device) to execute all or part of the steps of the above-mentioned data processing methods in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, ROM, RAM, mobile hard drives, magnetic disks, or optical disks.

[0060] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An automatic ladder control system suitable for ultra-large excavators, characterized in that: include: Limit switch self-test device (11) and controller (12); The limit switch self-test device is arranged at the ascending end point and the descending end point of the ladder, and comprises: a current driving unit (111) for outputting a test current in response to a controller instruction; A signal verification unit (112) is used to monitor in real time the level fluctuation of the trigger signal during the verification current output period; a self-checking judgment unit (113) outputs a valid trigger signal if the level fluctuation amplitude is less than or equal to a threshold value; and outputs a false trigger signal if the level fluctuation amplitude is greater than the threshold value; The controller (12) is connected to the limit switch self-test device (11) and is configured to: send a verification instruction to the current driving unit (111) when receiving a ladder action signal; receive a monitoring result from the signal verification unit (112) and determine the trigger validity; The controller (12) selectively performs the following operations according to the output of the self-checking and judging unit (113): if the ladder is in the process of ascending or descending, the self-checking and judging unit (113) outputs a valid trigger signal to prohibit the ladder from continuing to ascend or descend; if the ladder is in the process of ascending, the self-checking and judging unit (113) outputs a false trigger signal to start the segmented ascending mode; if the ladder is in the process of descending, the self-checking and judging unit (113) outputs a false trigger signal to shield the limit signal and allow the ladder to continue to descend.

2. The automatic ladder control system according to claim 1, characterized in that: The segmented ascent mode includes: In response to the continuous pressing signal of the rising switch, a segmented rising pulse instruction is generated in units of a preset safety time length; After each segmented rise is completed, it is necessary to detect the release state of the rise switch and re-trigger it to start the next rise cycle.

3. The automatic ladder control system according to claim 1, characterized in that: The controller (12) further comprises: a safety verification unit (121) for verifying multiple levels of safety conditions when performing a ladder descent operation, including: the engine is not started, the pilot switch is not turned on, the ladder descent limit switch is not turned on, and the ladder prohibition action button is not triggered.

4. The automatic ladder control system according to claim 3, characterized in that: The ladder prohibition action button is arranged at the ladder guardrail and is connected to the controller (12); when the ladder prohibition action button is triggered, a global interrupt signal is sent to the controller (12) to forcibly terminate all driving instructions.

5. The automatic ladder control system according to claim 1, characterized in that: The controller (12) further comprises: a ladder ascending stage protection unit (122), which outputs an alarm signal and locks the vehicle hydraulic valve when detecting that the pilot switch is turned on and the ladder ascending limit self-test result is not triggered or is falsely triggered.

6. The automatic ladder control system according to claim 1, characterized in that: The controller (12) further comprises a ladder descent stage protection unit (123), wherein when the ladder descent limit self-test result is effectively triggered, the controller (12) outputs a descent oil circuit interruption instruction to the hydraulic valve group, driving the locking mechanism to fix the current position of the ladder.

7. An automatic ladder control method suitable for ultra-large excavators, characterized in that: The following steps are involved: Obtaining a ladder climbing action request signal, including an ascending instruction or a descending instruction; Based on the rising instruction or the falling instruction, outputting a pulse calibration current to the limit switch self-test device at the corresponding end point; Acquire the trigger signal level fluctuation data during the calibration current output period; generating a valid trigger or false trigger determination signal based on a comparison result of the fluctuation data and a preset noise tolerance threshold; When the judgment signal is triggered effectively: if the ladder is in the ascending stage, the ladder is prohibited from continuing to ascend; if the ladder is in the descending stage, the ladder stops descending and outputs a mechanical locking signal; When the signal is determined to be falsely triggered: if the ladder is in the ascending stage, the ladder ascends in sections; if the ladder is in the descending stage, the ladder continues to descend.

8. An ultra-large excavator, characterized in that: include: The vehicle body, the hydraulically driven liftable ladder, and the automatic ladder control system suitable for ultra-large excavators as described in any one of claims 1-6 are provided.

9. A computer-readable storage medium storing program instructions, characterized in that: When the program instructions are executed by the processor, the steps of the automatic ladder climbing control method applicable to an ultra-large excavator as claimed in claim 7 are implemented.

10. A computer program product, characterized in that The invention comprises a computer program, which, when executed by a processor, implements the steps of the automatic ladder climbing control method applicable to an ultra-large excavator as claimed in claim 7.

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