Method for early warning of continuous hoist and continuous hoist

Abstract

The application aims to provide a hoisting early warning method of a continuous hoist and the continuous hoist, which adopts a fusion adjustment scheme of speed feedforward and level monitoring. Through weight-based speed feedforward control, the speed mutation at the instant of connection is eliminated, and the impact on the continuous hoist is reduced. Through real-time level monitoring and dynamic adjustment, the mechanical asynchronization caused by the difference in the tension of the conveying belt and the wear can be actively compensated, and the two cooperate to comprehensively reduce the tilting risk in the hoisting process and improve the safety and stability of operation.

Description

Technical Field

[0001] This invention relates to the field of logistics transportation, and more specifically to the control optimization and improvement of the process of transporting goods in the vertical direction. Background Technology

[0002] A continuous elevator is an automated device used in automated production lines, warehousing systems, or distribution centers to vertically transport materials or carriers. Its core function is to connect production or conveying links at different heights, enabling continuous and automated material flow in the vertical direction and reducing manual handling.

[0003] In existing technologies, common continuous lifting machines typically include two sets of lifting devices arranged symmetrically from left to right. Each lifting device usually consists of a conveyor belt arranged in a ring and pallets fixed at equal intervals on the conveyor belt. The conveyor belts of the two lifting devices are mechanically driven synchronously by the same drive shaft through a coupling, ensuring that the conveyor belts on both sides operate at the same linear speed. The pallets are supported and rise synchronously in the vertical direction, thereby achieving continuous lifting of materials.

[0004] However, this technical solution still has certain technical shortcomings. In actual use scenarios, especially after long-term operation, there are prominent issues affecting operational safety and stability during the lifting process. The pallet and the goods on it may tilt, and the lifting process may experience jamming or even stoppage. Summary of the Invention

[0005] The purpose of this invention is to provide a lifting early warning method and a continuous elevator. Markers are set on the conveyor belts of the left and right lifting devices, and the actual linear speeds of the two conveyor belts are monitored and compared in real time using visual sensors. When the speed difference exceeds a set threshold, the system issues an early warning signal before the pallet actually tilts. This scheme shifts the monitoring point from the result of tilting to the cause of synchronization deviation, achieving proactive prediction. Through the early warning mechanism, maintenance is prompted before malfunctions such as cargo tilting, tipping, or equipment jamming due to speed asynchrony occur, thus proactively ensuring the smooth operation of goods and the safety of the equipment, avoiding sudden downtime losses, and transforming post-fault handling into proactive preventative maintenance.

[0006] This invention provides a hoisting early warning method for a continuous hoist, comprising the following steps:

[0007] Each lifting device includes a separate conveyor belt, and visual markers are provided on each of the conveyor belts;

[0008] The visual capture device calculates the rotational speeds S_L and S_R of the left and right conveyor belts by recognizing the two visual markers on the left and right sides.

[0009] The real-time speed difference between the two conveyor belts is calculated based on S_L and S_R, and compared with the preset speed difference threshold.

[0010] When the real-time speed difference is greater than the speed difference threshold, the continuous hoist will not stop but will issue an early warning alarm.

[0011] As a preferred embodiment of the present invention, the visual capture device calculates the rotational speeds S_L and S_R of the left and right conveyor belts by identifying the two visual markers on the left and right. Specifically, the visual markers are reflective blocks, and the visual capture device calculates the rotational speed of each conveyor belt by the time it takes for the reflective blocks to cycle through a certain location.

[0012] As a preferred embodiment of the present invention, the acoustic signals of the two sets of lifting devices during operation are captured and compared with a preset abnormal sound database to determine whether there is a lifting abnormality. If there is a lifting abnormality, the continuous hoist will not stop but will issue an early warning alarm.

[0013] As a preferred embodiment of the present invention, each of the two sets of conveyor belts is individually equipped with a support arm, and the support arm is equipped with a load-bearing wheel for supporting the pallet. The capture of the acoustic signal during the operation of the two sets of lifting devices specifically involves capturing and analyzing the acoustic signal when the load-bearing wheel is working.

[0014] As a preferred embodiment of the present invention, the method for determining abnormal lifting is specifically as follows: the time difference between the abnormal sound patterns emitted by the load-bearing rollers and / or the sounds of the two sets of load-bearing rollers receiving the pallet exceeds a set threshold.

[0015] The lifting early warning method for continuous hoists includes the following steps:

[0016] Set up a mapping table between cargo weight H and lifting speed S;

[0017] Before lifting the cargo, the actual weight value H_C of the cargo is obtained in advance, and the corresponding lifting speed S is obtained based on the mapping table;

[0018] Set the lifting speed S to the lifting speed S_T of the continuous elevator, and lift the goods.

[0019] During the lifting process, the flatness data of the left and right lifting devices are monitored in real time, and the flatness of both sides is judged based on the flatness data. If it is judged to be uneven, the machine will stop and alarm.

[0020] As a preferred embodiment of the present invention, the method for determining flatness is as follows: each of the two lifting devices is equipped with a support arm for supporting the tray, and an optical generator and an optical receiver are arranged on the support arm. When the optical receiver does not receive the detection light, it is determined to be uneven.

[0021] As a preferred embodiment of the present invention: Before lifting the goods, the position of the goods in the width direction on the pallet is adjusted so that the goods are placed in the center.

[0022] A continuous elevator includes a frame, at least two sets of lifting devices, and a drive device for controlling the lifting devices. The frame is equipped with an inlet and an outlet, and each set of lifting devices is equipped with a support arm.

[0023] A pre-transfer plate is provided at the feeding position. The pre-transfer plate is equipped with a weight sensor for sensing the weight of the goods. An optical generator and an optical receiver are respectively provided on the two sets of support arms.

[0024] It also includes a control system for controlling the operating state of the drive unit, the control system being configured to execute the lifting early warning method for the continuous hoist described above.

[0025] As a preferred embodiment of the present invention, the lifting device includes a lifting frame, a conveyor belt connected to a rotating wheel mounted on the lifting frame, and a support arm connected to the conveyor belt.

[0026] As a preferred embodiment of the present invention, the support arm includes a plurality of load-bearing wheels, which are arranged in a horizontal array.

[0027] As a preferred embodiment of the present invention, the driving device drives one of the rotating wheels to rotate, and the two rotating wheels are connected by a linkage so that the two rotating wheels move synchronously.

[0028] As a preferred embodiment of the present invention, the pre-transfer plate is provided with a cargo positioning device, which is configured to adjust the lateral position of the cargo relative to the pallet.

[0029] As a preferred embodiment of the present invention, the positioning device includes a clearance post connected to the pre-transfer plate and an inclined guide plate, wherein the horizontal distance between the two guide plates gradually decreases as the cargo conveying direction moves forward.

[0030] As a preferred embodiment of the present invention: there are multiple weight sensors, and the center of gravity position data of the cargo is obtained through the multiple weight sensors. A fixed block is connected to the avoidance post, and an adjusting block is connected to the guide plate. The adjusting block is slidably connected to the fixed block, and the adjusting block is configured to adjust its position relative to the fixed block according to the center of gravity position data.

[0031] In summary, the present invention has the following beneficial effects:

[0032] 1. By visually monitoring and comparing the actual linear speeds of the left and right conveyor belts in real time, an early warning can be issued based on a speed difference threshold before the pallet actually tilts due to speed asynchrony. This early warning mechanism significantly shifts the fault handling point from "post-incident shutdown" to "pre-incident prevention," avoiding production interruptions caused by sudden shutdowns and proactively ensuring the smoothness of the cargo lifting process.

[0033] 2. Reflective blocks are used as visual markers, and the linear velocity is accurately measured by calculating the time it takes for them to cycle through a fixed point. This specific implementation method makes velocity monitoring more direct and reliable, less affected by ambient light, and the calculation logic is clear and efficient.

[0034] 3. Integrating acoustic signal analysis with visual monitoring, the mechanical condition is determined by comparing it with a pre-set abnormal sound database. This multi-dimensional monitoring method can cross-verify faults, especially for early mechanical wear or jamming noises that are difficult to detect visually, significantly improving the comprehensiveness of the early warning system and reducing false alarms and missed alarms.

[0035] 4. The acoustic signature monitoring signal is specifically limited to capturing the sound of the load-bearing roller during operation. Since the load-bearing roller is a key component that directly supports the load and is prone to abnormal friction, this design can most directly and sensitively capture early fault characteristics caused by abnormal load-bearing contact, realizing targeted monitoring of the health status of the core load-bearing component.

[0036] 5. Two specific acoustic criteria for abnormal lifting and lowering were identified: one is the appearance of specific abnormal sound patterns, and the other is the temporal difference in the sound of a set of load-bearing wheels. This system can identify both the qualitative characteristics of component damage and the quantitative differences in asynchronous movement between the two sides, making the early warning judgment more comprehensive and effectively distinguishing different types of potential fault modes.

[0037] 6. By pre-setting an appropriate lifting speed based on the weight of the cargo, the acceleration impact during the connection and start-up phases is effectively eliminated. Simultaneously, real-time monitoring of flatness during the lifting process and alarm shutdown in case of abnormalities can promptly prevent cargo slippage or overturning due to tilting, thus significantly improving the safety and stability of the lifting process.

[0038] 7. Flatness is determined by using optical generators and receivers that shoot out from each other on both sides of the support arms, achieving a high-response, non-contact, real-time monitoring method. This method is unaffected by mechanical vibration, has high detection accuracy, and can reliably capture minute height differences in the support arms, providing an accurate basis for safety assessment.

[0039] 8. Before lifting, proactively adjust the lateral position of the goods on the pallet to center them, which can effectively regulate the posture of the goods. This reduces the additional overturning moment caused by the eccentric placement of the goods from the source, lowers the risk of tilting during the lifting process, and further enhances the stability and safety of the operation.

[0040] 9. The lifting arm is raised and lowered using a conveyor belt driven by rotating wheels. This design is simple and reliable, enabling continuous and cyclical lifting operations. The lifting frame provides stable support and guidance for the entire lifting device, ensuring the stable vertical trajectory of the conveyor belt and lifting arm.

[0041] 10. The support arm uses multiple horizontally arrayed load-bearing rollers to support the pallet, converting sliding friction into rolling friction, which significantly reduces the motion resistance between the support arm and the bottom of the pallet. This not only makes operation smoother and energy consumption lower, but also reduces wear on the pallet and helps maintain the pallet's levelness during lifting.

[0042] 11. A cargo positioning device is installed on the pre-transfer plate, which enables automatic physical adjustment of the lateral position of the cargo during weighing. This design integrates the positioning function into the lifting process, eliminating the need for manual intervention or additional workstations. It is highly automated and effectively ensures the standardization of the cargo's posture before entering the continuous elevator.

[0043] 12. The positioning device employs inclined guide plates with their spacing gradually decreasing along the conveying direction. Utilizing the inertia of the goods' forward movement, the inclined surfaces of the guide plates automatically guide the goods to the centered position. This structure operates purely mechanically, requiring no additional power, and achieves a reliable and low-cost automatic centering function.

[0044] 13. Multiple weight sensors acquire cargo center of gravity data and drive the adjustment blocks to move, thereby changing the guide plate spacing. This allows the positioning device to adaptively adjust the width according to the actual center of gravity distribution of the cargo, achieving more precise centering for unbalanced loads, thus more effectively preventing tilting and demonstrating a high degree of intelligence. Attached Figure Description

[0045] Figure 1 This shows a front view of the continuous hoist of Embodiment 1;

[0046] Figure 2 It shows Figure 1 A 3D schematic diagram of the part behind the hidden door panel;

[0047] Figure 3 A schematic diagram of the pre-transfer plate of Embodiment 1 is shown;

[0048] Figure 4 A flowchart illustrating the improved early warning method is shown;

[0049] Figure 5 A flowchart illustrating the enhanced early warning method incorporating voiceprint analysis is shown.

[0050] Figure 6 A flowchart illustrating the safety control method is shown.

[0051] In the diagram: 1. Frame, 11. Feed position, 12. Discharge position, 2. Lifting device, 21. Rotating wheel, 22. Conveyor belt, 23. Lifting frame, 3. Support arm, 31. Load-bearing wheel, 4. Drive device, 5. Linkage device, 6. Pre-transfer plate, 7. Cargo positioning device, 71. Clearance column, 72. Fixed block, 73. Adjusting block, 74. Guide plate, 9. Pallet. Detailed Implementation

[0052] The present invention will be further described in detail below with reference to the accompanying drawings.

[0053] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings.

[0054] The terms "first," "second," "third," etc., in the description, claims, and accompanying drawings are used to distinguish different objects, not to describe a particular order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0055] The following description provides examples and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the described elements without departing from the scope of this specification. Various processes or components may be appropriately omitted, substituted, or added to the examples. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined into other examples.

[0056] As stated in the background section, a careful analysis of existing continuous lifting machines and methods reveals that while a basic continuous lifting function is achieved based on a structure with two sets of mechanical synchronous conveyor belts, its design inherently contains flaws. These flaws lead to significant problems affecting operational safety and stability during the lifting process, particularly during the transfer and high-speed operation phases. These flaws manifest in two aspects, both directly related to the mechanical synchronous conveyor belt structure.

[0057] On one hand, there is the vibration and impact caused by sudden speed changes. Because the lifting mechanism moves at a predetermined constant speed or constant acceleration, while the pallet entering the device is initially moving horizontally, meaning its vertical velocity is zero, at the moment of connection, the pallet is forcibly switched from horizontal movement to vertical lifting. This sudden change in direction and speed generates a significant acceleration impact. This "rigid" connection process lacks buffering and adaptability, causing the pallet and goods to vibrate during the initial lifting phase, posing a safety risk to delicate or fragile goods.

[0058] On the other hand, there is the risk of tilting due to mechanical synchronization failure. Although the left and right lifting structures achieve initial mechanical synchronization through couplings, after long-term, high-load operation, tension differences inevitably arise on both sides of the conveyor belts, accompanied by varying degrees of wear. This tension difference and wear directly disrupt the actual motion synchronization of the lifting structures on both sides, causing a height difference between the two lifting blocks supporting the same pallet during the ascent. The direct consequence is that the pallet tilts during lifting, which in severe cases can cause goods to slip or even overturn, posing a serious safety hazard. Existing purely mechanical structures cannot monitor and compensate for this dynamic asynchrony caused by long-term use.

[0059] In summary, the core design flaw of the existing technology lies in its purely mechanical, open-loop control method, which cannot cope with the dynamic speed impact during connection, nor can it overcome the mechanical asynchrony problem caused by long-term use. Therefore, it has significant deficiencies in terms of the smoothness and safety of the lifting process.

[0060] Example 1, such as Figure 1 and Figure 2 As shown, a continuous lifting machine is designed to address safety issues such as shaking and tilting caused by sudden speed changes and mechanical asynchrony during cargo transfer and lifting in existing logistics continuous lifting machines. This solution achieves stable and safe continuous lifting through a comprehensive approach involving weight sensing, speed pre-control, level monitoring, and automatic positioning.

[0061] The continuous elevator includes a frame 1, which forms the main support frame of the equipment. A feed inlet 11 is located at the bottom of the frame 1 to receive goods to be lifted and pallets 9; a discharge outlet 12 is located at the top of the frame 1 to transport the lifted goods to the next process. In other embodiments, the heights of the feed inlet 11 and the discharge outlet 12 can be reversed.

[0062] Two sets of lifting devices 2 are symmetrically arranged on the left and right sides inside the frame 1 to provide the main vertical lifting power. The drive device 4 is fixedly installed on the frame 1 to drive the lifting devices 2. In this embodiment, the drive device 4 is preferably a servo motor with a reducer, which can provide precise speed and position control, which is the basis for achieving subsequent precise speed matching.

[0063] Each lifting device 2 includes a vertically fixed lifting frame 23, which is a rectangular frame structure that provides robust guidance and support for the moving parts on it. Rotating wheels 21 are installed at the top and bottom of the lifting frame 23, and a conveyor belt 22 is arranged around the two rotating wheels 21, thus forming a circular vertical transmission path.

[0064] More specifically, the output shaft of the drive unit 4 directly drives one of the rotating wheels 21 of one of the lifting devices 2, and the rotating wheels 21 on the drive side of the two lifting devices 2 are connected by a rigid linkage 5. The linkage 5 can be a coupling in the prior art. This linkage 5 ensures that the rotating wheels 21 of the two sets of lifting devices 2 can achieve strict mechanical synchronous rotation, thus laying a solid foundation for the synchronous movement of both sides from the power source and effectively avoiding the initial asynchrony problem that may occur due to different motor drives.

[0065] The conveyor belt 22 is fixedly connected to a support arm 3. The support arm 3 is a key component that directly supports the pallet 9. For example... Figure 2 As shown, each support arm 3 is equipped with multiple load-bearing rollers 31, which are arranged in a horizontal array. When the support arm 3 lifts the pallet 9, the load-bearing rollers 31 form rolling contact with the bottom of the pallet 9. This design transforms traditional sliding friction into rolling friction, which significantly reduces motion resistance during the lifting process, making the operation smoother and more stable. It also reduces power consumption and wear on the bottom of the pallet 9, and helps maintain the stability of the pallet 9. The support arms 3 on the left and right sides always work in pairs. When a pair of support arms 3 moves to the bottom of the device, they are positioned directly below the left and right sides of the pallet 9, respectively, thus working together to lift the pallet 9.

[0066] One improvement in this device is the pretreatment at the feed point 11. For example... Figure 1 and Figure 3 As shown, a pre-transfer plate 6 is installed at the inlet position 11. The pre-transfer plate 6 itself is a transfer station responsible for conveying the pallet 9 to the accurate docking position.

[0067] A weight sensing module, containing load cells, is integrated inside the pre-transfer plate 6. This module is located below the pre-transfer plate 6. When the pallet 9 carrying the goods is fully inserted into the pre-transfer plate 6, the load cells can accurately measure the total weight of the goods and the pallet 9.

[0068] like Figure 3As shown, this device includes a cargo positioning device 7 above the pre-transfer plate 6. The main function of this device is to automatically adjust the lateral position of the cargo on the pallet 9 before lifting, ensuring that its center of gravity is as close as possible to the centerline of the pallet 9's width. The cargo positioning device 7 comprises two symmetrically arranged positioning units. Each unit includes a vertically fixed clearance post 71 on the side of the pre-transfer plate 6, with a fixed block 72 fixedly connected to the clearance post 71. An adjusting block 73 is slidably connected to the fixed block 72 via a slide rail slider mechanism, allowing the adjusting block 73 to move horizontally relative to the fixed block 72. The driving source can be a servo electric cylinder or a pneumatic cylinder.

[0069] A guide plate 74 is connected to the adjusting block 73. The two guide plates 74 are positioned opposite each other, and their inner guide surfaces are arranged in a V-shape in the top view, meaning that the horizontal distance between them gradually decreases along the direction of the goods' movement. After obtaining the lateral offset data of the goods' center of gravity, the control system can drive the two adjusting blocks 73 to move towards or away from each other, thereby adjusting the distance between the two guide plates 74 at their narrowest points. When the pallet 9 is conveyed forward on the pre-transfer plate 6, the pallet 9 passes through the space under the two guide plates 74, and the side of the goods contacts the inclined surface of the guide plates 74. Under the action of the forward thrust, the goods are automatically guided and centered within the preset distance. The direct benefit of this design is that it can actively correct the placement posture of the goods before they enter the lifting area, physically reducing the additional overturning moment caused by the offset of the goods' center of gravity, fundamentally reducing the risk of tilting due to uneven force during subsequent lifting, and is a proactive safety measure.

[0070] Furthermore, the adjusting block 73 is provided with a vertically extending rotating shaft, on which a guide plate 74 is connected, and a torsion spring is provided on the rotating shaft to abut against the adjusting block 73. This allows the guide plate 74 to swing relative to the adjusting block 73 to a certain extent, avoiding excessive rigidity that would prevent the forward transmission of goods and thus avoid congestion at this point.

[0071] Another key improvement of this device lies in real-time status monitoring. Flatness monitoring components are installed on the left and right support arms 3 respectively. Specifically, an optical generator, such as an infrared laser emitter, is installed on one support arm 3, and an optical receiver is installed at a corresponding height on the opposite support arm 3.

[0072] When the pair of support arms 3 are at the same horizontal height, the light beam emitted by the optical generator should be stably received by the optical receiver. If, during the lifting process, a height deviation occurs between the left and right support arms 3 due to differences in conveyor belt tension or uneven wear, the light beam path is blocked, and the optical receiver signal is lost. This non-contact optical detection method offers fast response, high accuracy, and is less susceptible to mechanical vibration or environmental influences. It can reliably detect minute asynchrony phenomena, providing immediate and accurate signals for real-time safety assessment.

[0073] All the aforementioned hardware is coordinated and controlled by a centralized control system. This control system is exemplary and can be an industrial control unit comprised of a programmable logic controller (PLC), a motion controller, and a touchscreen human-machine interface. The control system is electrically connected to the drive unit 4, the weight sensor on the pre-transfer plate 6, and the optical monitoring components on the support arm 3. The core task of the control system is to implement the following safety control methods, organically integrating the various hardware units to achieve intelligent enhancement.

[0074] like Figure 4 As shown, Figure 4 This refers to the lifting early warning method for the continuous hoist described above (200).

[0075] In box 201, the visual monitoring system for implementing method 200 is initialized and the speed reference is acquired. The specific implementation of this step involves hardware deployment and software calibration. On the conveyor belt 22 of each lifting device 2, a highly reflective visual marker is securely affixed to an easily obstructed and readily observable location.

[0076] Preferably, the marker is a strip or block of industrial reflective material. A vision capture device, such as a high-speed industrial camera or photoelectric sensor, is fixedly installed at the position of frame 1 directly opposite the running trajectory of the marker.

[0077] The vision capture device continuously captures images of a localized area containing the markers through its lens. As the conveyor belt 22 rotates, the markers move in a cyclical pattern. The control system uses an image recognition algorithm to precisely capture the time interval between two passes of the same marker across the reference line at the center of the vision capture device's field of view. Based on the known circumference of the conveyor belt 22, or the fixed distance between the two markers, the real-time linear rotational speeds S_L or S_R of the two conveyor belts 22 (left and right) can be calculated.

[0078] In block 202, the real-time speed difference ΔV between the two conveyor belts is calculated based on S_L and S_R, and compared with a preset speed difference threshold V_th. For example, the control system synchronously acquires and updates the values ​​of S_L and S_R at a fixed sampling frequency. Subsequently, the absolute value of the instantaneous speed difference ΔV = |S_L - S_R| is calculated in real time. Simultaneously, one or more speed difference thresholds V_th are preset within the system.

[0079] The threshold V_th is set based on extensive experiments and mechanical simulations. Its critical value corresponds to a speed deviation that, under typical load and lifting height, is sufficient to accumulate within seconds or tens of seconds to cause the pallet 9 to tilt dangerously. The control system continuously compares ΔV with V_th in real time.

[0080] In box 203, when the real-time speed difference ΔV is determined to be greater than the preset threshold V_th, the control system triggers an early warning alarm, and the continuous hoist does not perform an emergency shutdown.

[0081] Specifically, once the condition ΔV > V_th is met, the control system immediately sends a warning command to the human-machine interface (HMI). The indicator light in the corresponding area on the HMI turns flashing yellow, and a warning window pops up on the screen, displaying "Warning: Left and right conveyor belt speeds are out of sync" and the current ΔV value, with the option to accompany it with a gentle prompt sound.

[0082] Meanwhile, the control system continues to execute the normal lifting process, and the drive unit 4 maintains its current operating state.

[0083] The fundamental advantage of the method 200 provided by this invention lies in its implementation of a preventative mechanism. Instead of addressing the issue only after the pallet has become observably tilted, this method directly monitors the real-time linear speeds of the left and right conveyor belts and performs a high-precision comparison of their speed differences. In such continuous elevators, the tilting or asynchronous lifting of the pallet is often caused by mechanical problems such as tension changes and uneven wear of the conveyor belts due to long-term operation. These faults directly manifest as subtle differences in the actual linear speeds of the left and right conveyor belts. Therefore, by directly focusing the detection on the conveyor belt itself and monitoring its linear speed difference, early signs of synchronicity failure can be captured with extreme sensitivity and precision.

[0084] Ultimately, the technical objective of this method is not to directly adjust or control the tension of the conveyor belt, but rather to use the linear speed difference as an early warning indicator. This allows for timely warnings at the early stages, before mechanical asynchrony begins to emerge and before it causes pallet imbalance and overturning. This represents a paradigm shift from "result correction" to "cause warning," enabling proactive maintenance and significantly improving the safety and reliability of the entire lifting process, thus avoiding production interruptions and safety risks caused by sudden malfunctions.

[0085] like Figure 5 As shown, Figure 5 The above refers to the lifting early warning method 300 for the continuous hoist.

[0086] The method 300 provided by this invention, like method 200, is also an early warning method. That is, it is an early warning method that occurs before an unstable event affecting the lifting and lowering process occurs, rather than a control or stopping method that occurs during the event.

[0087] Method 300 is a functional enhancement based on Method 200. It does not rely solely on visual velocimetry, but integrates two heterogeneous perception modalities: visual linear velocity monitoring and voiceprint anomaly recognition.

[0088] By introducing real-time analysis and comparison of the acoustic signatures of key mechanical components such as load-bearing wheels, Method 300 can capture early hidden faults that are difficult to detect by traditional speed monitoring, such as initial wear of bearings, lubrication failure, or intrusion of tiny foreign objects. This multimodal strategy achieves complementarity and cross-validation of monitoring dimensions: visual monitoring is good at discovering macroscopic trends of asynchronous motion, while acoustic signature recognition can keenly perceive microscopic deterioration of mechanical contact conditions.

[0089] Method 300 includes all the steps of Method 200 above, and further includes the voiceprint detection content described below.

[0090] like Figure 5 As shown, in box 301, the acoustic signals of the two sets of lifting devices 2 during operation are captured and compared with the preset abnormal sound database.

[0091] Specifically, high-sensitivity industrial acoustic sensors are installed near the load-bearing wheels 31 on both the left and right side support arms 3. Their installation positions must ensure clear acquisition of the sound generated when the load-bearing wheels 31 contact the bottom of the tray 9 and roll, while minimizing ambient noise. These acoustic sensors are connected to the control system.

[0092] After system debugging or overhaul, normal sound samples are collected from the equipment under normal conditions and with increased standard load over a period of time. After filtering and feature extraction, a "normal voiceprint" benchmark model is established.

[0093] Meanwhile, by simulating experiments or collecting historical fault data, samples such as periodic sounds from bearing damage, dry friction sounds from poor lubrication, and sharp scraping sounds from foreign objects stuck together are obtained to construct an "abnormal soundprint database".

[0094] Box 301 adds an auditory perception dimension to the device. The sound signal contains rich mechanical condition information and can capture early fault features that cannot be directly detected by visual and speed sensors, such as early pitting of bearings, minor foreign object intrusion, or minor deterioration of lubrication, enabling uninterrupted and non-invasive monitoring of the health status of core load-bearing components.

[0095] In frame 302, the acoustic signature signal of the lifting device is collected in real time.

[0096] In block 303, a determination is made as to whether there is an abnormal rise or fall based on the acquired voiceprint signal. For example, it may include two parallel or selective determination logics.

[0097] The first method is abnormal voiceprint matching and determination. The system extracts the same features from the real-time collected voiceprint signals and performs pattern matching calculations, such as calculating cosine similarity, against samples in the "abnormal voiceprint database." If the matching degree between the real-time voiceprint and any abnormal sample exceeds a set confidence threshold, a specific type of mechanical anomaly is determined to exist.

[0098] The second method is timing difference determination. Since the left and right support arms 3 should theoretically contact and support the tray 9 simultaneously, the "load-bearing contact" sound pulses collected by the two acoustic sensors should be almost synchronized. The system uses a signal processing algorithm to accurately identify the rising edge of the "contact sound" pulses in the sound signals from both sides and calculates their time difference Δt. If Δt continuously exceeds a set threshold, such as 20 milliseconds, it is determined that there is an asynchrony in the left and right load-bearing actions. At this point, because this set threshold value is relatively small, the tray 9 has not actually tilted significantly, but this slight asynchrony could be a precursor signal for the tray 9 to tilt.

[0099] Box 303 is a crucial step that combines qualitative and quantitative fault diagnosis. Abnormal soundprint matching can qualitatively diagnose the fault type, such as an abnormality in the left load-bearing wheel bearing. Meanwhile, timing difference determination can quantitatively capture the loss of synchronization in the movements of both side support arms. The combination of these two methods allows the system to not only determine "whether there is an abnormality," but also to preliminarily determine "where the abnormality is" and "what kind of abnormality," greatly improving the targeted nature of maintenance guidance.

[0100] In some preferred embodiments, a fusion decision is made by combining the visual speed difference determination in method 200 and the voiceprint rise and fall anomaly determination in method 300.

[0101] Specifically, a hierarchical decision matrix is ​​preset within the control system. This matrix combines the visual speed difference alarm status of box 202 with the voiceprint anomaly judgment status of box 302 to output a comprehensive warning level.

[0102] For example: (1) Visual speed difference warning only, voiceprint normal: judged as "basic warning", indicating that there may be slight drift of electrical parameters of speed ring or initial tension difference. (2) Voiceprint abnormality only, visual speed normal: judged as "intermediate warning", indicating that there may be local mechanical damage but has not yet affected the overall synchronization. (3) Visual speed difference warning and voiceprint abnormality occur at the same time: judged as "high-level warning", indicating that the mechanical failure has developed to a serious stage affecting motion synchronization.

[0103] This fusion decision-making, through cross-validation of information from multiple sensors, reduces the possibility of false alarms from a single sensor and enables the assessment of the severity and stage of a fault.

[0104] In box 304, the corresponding early warning alarm is executed according to the early warning level of the fusion decision, and the continuous hoist does not perform an emergency shutdown under this method path.

[0105] The core reason for introducing acoustic signature monitoring throughout Method 300 is its ability to capture early mechanical anomalies that cannot be detected by visual and speed sensors, such as microscopic wear of bearings, lubrication failure, or intrusion of minute foreign objects. While these latent faults do not immediately affect speed, they are the root cause of subsequent severe asynchrony. The focus is on monitoring the synchronicity of the two load-bearing rollers because they are the core stress points directly supporting the pallet. The sounds of the left and right load-bearing rollers contacting the pallet should ideally be nearly synchronized; their time difference directly and sensitively reflects the consistency of the actions of both support arms. Monitoring this synchronicity allows for earlier warnings of the risk of load asynchrony at the source of mechanical contact, enabling deeper pre-diagnosis.

[0106] like Figure 6 As shown, Figure 6 This refers to the safety control method 100 for the continuous hoist described above.

[0107] Method 100 differs from methods 200 and 300 described above. Method 100 is a safety control method, while methods 200 and 300 are methods to enhance early warning capabilities.

[0108] Method 100 is a post-incident safety control mechanism. Its technical logic involves real-time monitoring of the pallet's actual flatness during the lifting process using an optical generator and receiver on the support arm. If the optical signal is interrupted, the system determines that the pallet has tilted at a risk and immediately triggers an emergency stop and alarm. Therefore, the core purpose of this method is to intercept the accident in progress when mechanical asynchrony has already led to adverse consequences, preventing the accident from escalating and ensuring the safety of personnel and equipment.

[0109] Specifically, such as Figure 6 As shown, in box 101, there is a mapping table for setting the cargo weight H and lifting speed S to implement method 100.

[0110] This mapping table defines the optimal lifting speed curves corresponding to different weight ranges. For example, the following mapping relationship can be preset: for light goods weighing 0-50 kg, the corresponding lifting acceleration is 0.3 m / s², and the maximum lifting speed is 1.0 m / s; for medium goods weighing 50-200 kg, the corresponding lifting acceleration is 0.2 m / s², and the maximum speed is 0.8 m / s; for heavy goods weighing 200-500 kg, a gentler acceleration of 0.1 m / s² and a maximum speed of 0.5 m / s are used.

[0111] The direct benefit of this weight-based graded speed feedforward control is that it can match the most suitable dynamic parameters for different loads, eliminate the inertial impact at the moment of connection from the source, and achieve the optimization effect of "slow start and stable operation for heavy goods, and fast speed and efficiency improvement for light goods".

[0112] In box 102, the lifting speed S of method 100 is calculated. Before lifting the cargo, the actual weight value H_C of the cargo is obtained in advance, and the corresponding lifting speed S is obtained based on the mapping table.

[0113] Specifically, once pallet 9 is conveyed onto pre-transfer plate 6 and comes to a stop, the weight sensor completes the weighing within a short time. For example, if the actual weight H_C of the goods is measured to be 150 kg, the control system, based on the mapping table, determines that it belongs to the "medium-sized goods" category and retrieves the corresponding velocity curve, with an acceleration of 0.2 m / s² and a maximum speed of 0.8 m / s, as the preset speed S for this lifting operation. This step enables the specific customization of the control strategy, providing an accurate data foundation for subsequent smooth lifting.

[0114] In box 103, the lifting speed S is set to the lifting speed S_T of the continuous elevator, and the goods are lifted. The control system issues the calculated speed curve S to the drive unit 4 as a target command. For example, for the aforementioned 150 kg goods, the drive unit starts with an acceleration of 0.2 m / s², smoothly lifting the pallet.

[0115] Meanwhile, as the lifting process continues, system execution block 104 monitors the flatness data of the left and right lifting devices in real time. This is achieved through optical components on the support arm 3. For example, the control system samples the signal from the optical receiver at a frequency of 100 times per second.

[0116] The flatness data is used to determine the flatness of both sides. If the flatness is determined to be uneven, the machine will stop and an alarm will be triggered.

[0117] The logic for leveling is as follows: if the optical receiver signal is continuously lost for more than a preset short time limit during the lifting process, such as 20 milliseconds, it is determined that a risky tilt has occurred.

[0118] At this moment, the control system issues an emergency stop command to drive unit 4 within milliseconds and sounds the alarm. For example, if the height difference between the left and right support arms reaches 3 millimeters due to slippage of one conveyor belt, the beam is blocked, and the system immediately alarms and stops the machine. This real-time monitoring and rapid response mechanism can proactively capture early tilting trends caused by mechanical asynchrony, interrupting operations in time before an accident becomes apparent, transforming safety management from post-accident remediation to in-process prevention, and significantly improving the proactive safety of the system.

[0119] In summary, in the specific implementation of this continuous hoist, the hoisting speed control based on the weight of the cargo and the real-time flatness monitoring during the hoisting process work together to form the core mechanism for ensuring operational safety and equipment reliability.

[0120] Specifically, before the connection and lifting, the system first matches a suitable lifting speed curve from a preset mapping table based on the weight of the goods obtained by the weighing module. This speed control strategy achieves smooth acceleration management, and its direct effects are: on the one hand, it significantly reduces the jerking and shaking of the goods during the start-up phase, improving the stability and safety of transportation; on the other hand, by reducing the impact of movement, it effectively alleviates the instantaneous stress on flexible or moving parts such as conveyor belts and support arms, helping to delay their fatigue aging and deformation, fundamentally maintaining the mechanical reliability of the device itself, and extending its service life.

[0121] During the lifting process using the optimized speed curve described above, optical flatness monitoring components installed on the left and right support arms simultaneously perform millisecond-level real-time monitoring. This design creates a crucial safety redundancy: even with the speed control optimized for optimal operating conditions, if the tray tilts due to long-term wear, unexpected jamming, or any other reason, the monitoring system can immediately and accurately identify this abnormal state and trigger an emergency stop and alarm.

[0122] Therefore, the synergy between the two technologies is reflected in their timing and functional integration: speed control focuses on proactive optimization and prevention, aiming to create stable conditions and protect the equipment; while flatness monitoring focuses on real-time supervision and post-event backup, ensuring that risks can be intercepted immediately when anomalies occur. Together, they provide systematic protection for cargo safety and equipment lifespan.

[0123] Example 2: Multiple high-precision weighing sensors are evenly arranged in a matrix below the platform of the pre-transfer plate 6. For example, four sensors can be located near the four corners of the platform to jointly support and sense the weight of the entire pre-transfer plate 6 and the goods on it.

[0124] When the pallet 9 carrying the goods is fully inserted into and stationary on the pre-transfer plate 6, four sensors simultaneously measure the pressure values ​​at their respective support points. The control system collects this data in real time and, based on the known geometric coordinates of the sensors, calculates the two-dimensional coordinates of the goods' center of gravity on the horizontal plane using a mechanical calculation model, particularly its offset in the width direction of the pallet. The direct advantage of this multi-sensor collaborative calculation method for the center of gravity is that it can go beyond simple weight measurement and accurately identify uneven mass distribution of the goods' load. Even with the same total weight, the threat to stability posed by a goods with a centrally located center of gravity is completely different from that of a goods with a severely left-biased center of gravity.

[0125] After acquiring the lateral offset data of the center of gravity, the control system immediately drives the cargo positioning device 7 to operate. The adjusting block 73 can be connected to the fixed block 72 via a linear slide rail and can slide horizontally along the width of the pallet under the drive of a servo electric cylinder or a precision ball screw.

[0126] Based on the calculated lateral offset direction and magnitude of the center of gravity, the positions of the two guide plates 74 required to guide the cargo's center of gravity to the target centerline are determined. This adaptive adjustment based on center of gravity data avoids overturning moments caused by improper cargo placement.

[0127] In this embodiment, the data acquisition, distance calculation, and movement execution actions are still implemented by the control system described above.

[0128] The above are merely preferred embodiments of the present invention and are 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 scope of protection of the present invention.

[0129] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

Claims

1. A hoisting early warning method for a continuous hoist, characterized in that, It includes the following steps: Each lifting device includes a separate conveyor belt, and visual markers are provided on each of the conveyor belts; The visual capture device calculates the rotational speeds S_L and S_R of the left and right conveyor belts by recognizing the two visual markers on the left and right sides. The real-time speed difference between the two conveyor belts is calculated based on S_L and S_R, and compared with the preset speed difference threshold. When the real-time speed difference is greater than the speed difference threshold, the continuous hoist will not stop but will issue an early warning alarm.

2. The hoisting early warning method for a continuous hoist according to claim 1, characterized in that: The visual capture device calculates the rotation speeds S_L and S_R of the left and right conveyor belts by identifying the two visual markers on the left and right. Specifically, the visual markers are reflective blocks, and the visual capture device calculates the rotation speed of each conveyor belt by the time it takes for the reflective block to cycle through a certain location.

3. The hoisting early warning method for a continuous hoist according to claim 1, characterized in that: The system captures acoustic signals from the operation of the two lifting devices and compares them with a pre-set database of abnormal sounds to determine if there is an abnormality in the lifting mechanism. If there is an abnormality, the continuous hoist will not stop but will issue a warning alarm.

4. The hoisting early warning method for a continuous hoist according to claim 3, characterized in that: Both sets of conveyor belts are individually equipped with support arms, and the support arms are equipped with load-bearing wheels for supporting the pallets. The capture of acoustic signals during the operation of the two sets of lifting devices specifically involves capturing and analyzing the acoustic signals when the load-bearing wheels are working.

5. The hoisting early warning method for a continuous hoist according to claim 4, characterized in that: The specific method for judging abnormal lifting is that the load-bearing roller emits an abnormal sound pattern stored in the database and / or the time difference between the two sets of sounds of the load-bearing roller receiving the pallet exceeds a set threshold.

6. The hoisting early warning method for a continuous hoist according to claim 1, characterized in that: Before lifting the goods, adjust their position on the pallet in the width direction to center them.

7. A continuous elevator, comprising a frame (1), at least two sets of lifting devices (2) and a drive device (4) for controlling the lifting devices (2), wherein the frame (1) is provided with an inlet position (11) and an outlet position (12), and each set of lifting devices (2) is provided with a support arm (3), characterized in that: A pre-transfer plate (6) is provided at the feeding position (11). The pre-transfer plate (6) is equipped with a weight sensor for sensing the weight of the goods. An optical generator and an optical receiver are respectively provided on the two sets of support arms (3). It also includes a control system for controlling the operating state of the drive unit (4), the control system being configured to perform the lifting early warning method for the continuous hoist as described in any one of claims 1-6.

8. The continuous elevator according to claim 7, characterized in that: The lifting device (2) includes a lifting frame (23), a rotating wheel (21) mounted on the lifting frame (23) and a conveyor belt (22) connected to the rotating wheel (21), and a support arm (3) connected to the conveyor belt (22). The support arm (3) includes a load-bearing wheel (31).

9. The continuous elevator according to claim 7, characterized in that: The pre-transfer plate (6) is provided with a cargo positioning device (7), which is configured to adjust the lateral position of the cargo relative to the pallet.

10. The continuous elevator according to claim 9, characterized in that: The cargo positioning device (7) includes a clearance post (71) connected to the pre-transfer plate (6) and an inclined guide plate (74), the horizontal distance between the two guide plates (74) gradually shortens as the cargo conveying direction moves forward.

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