Vertical tensioning device and control method

Abstract

This invention discloses a vertical tensioning device and control method, relating to the technical field of conveyors. It aims to address the shortcomings of existing tensioning devices, such as large space occupation, complex structure, and difficulty in maintenance. The device includes a redirecting roller, a counterweight device, a tensioning bracket, a non-contact displacement sensor, a controller, and an alarm. The counterweight device includes a bridge-shaped platform, a tensioning roller, and two counterweight boxes. The bridge-shaped platform includes a protrusion and a platform section. The tensioning roller is located below the protrusion, and the two counterweight boxes are respectively located on the platform sections on both sides. The tensioning bracket includes multiple vertically arranged guide columns, allowing the counterweight device to be slidably mounted on these columns. The non-contact displacement sensor continuously monitors the real-time position of the counterweight device. The controller pre-stores the upper and lower limits of the safe travel distance of the counterweight device, as well as a reference position. This invention reduces the number of components through integrated design, lowering equipment and maintenance costs, resulting in a simpler structure and more convenient operation.

Description

Technical Field

[0001] This invention relates to the technical field of conveyors. More specifically, this invention relates to a vertical tensioning device and its control method. Background Technology

[0002] In the field of conveyors, tensioning devices are core components ensuring stable equipment operation. Their primary function is to maintain sufficient tension at the minimum tension point of the conveyor belt, meeting both the basic requirements of friction drive and strictly controlling the belt sag within reasonable limits, thereby achieving efficient and continuous material transport. Vertical tensioning devices, in particular, are widely used in the industry due to their outstanding advantages. These advantages include a simple structural design, generating stable tension without additional driving force, significantly reducing operating costs; consistent and reliable tension, high safety, and a smaller horizontal space requirement compared to other types of tensioning devices, making them suitable for various complex installation scenarios.

[0003] With the rapid development of industrial technology, long-distance, high-capacity conveyors have gradually become the mainstream equipment. These conveyors place new demands on tensioning devices—the tensioning stroke needs to be significantly increased, and the size of the matching counterweight box also needs to be enlarged accordingly. This directly leads to a sharp increase in the vertical space required for traditional vertical tensioning devices. In the actual design and installation of conveyors, the dilemma of being constrained by both horizontal and vertical space at the tensioning position is often encountered. To address this problem, the industry has currently developed two mainstream technical solutions, but both have obvious shortcomings.

[0004] The first approach involves installing an independent vertical tensioning device at both the head and tail of the conveyor. While this approach alleviates space constraints to some extent, the coordinated operation of the two devices significantly increases the complexity of the system control logic. This not only increases the initial investment cost of the equipment but also makes subsequent equipment maintenance and troubleshooting more cumbersome, leading to a substantial increase in maintenance costs.

[0005] The second option (such as) Figure 1 As shown in the diagram, three redirecting rollers, two tensioning rollers, and two counterweight boxes are installed at the tensioning position. This solution adapts to space requirements by increasing the number of rollers and counterweight boxes, but it doubles the tension force, exceeding the actual needs of some scenarios. At the same time, the increase in the number of redirecting rollers, tensioning rollers, and counterweight boxes directly leads to an increase in equipment maintenance points, which not only increases the equipment procurement and installation costs, but also causes the daily maintenance workload and maintenance costs to rise simultaneously.

[0006] Therefore, it is necessary to design a technical solution that can overcome the above-mentioned defects to a certain extent. Summary of the Invention

[0007] One objective of this invention is to provide a vertical tensioning device and control method that reduces the number of components through integrated design, thereby lowering equipment and maintenance costs, and resulting in a simpler structure and more convenient operation.

[0008] To achieve these objectives and other advantages of the present invention, according to one aspect of the present invention, a vertical tensioning device is provided, comprising a redirecting roller, a counterweight device, a tensioning bracket, a non-contact displacement sensor, a controller, and an alarm. The counterweight device includes a bridge-shaped platform, a tensioning roller, and two counterweight boxes. The bridge-shaped platform includes a central protrusion and platform portions on either side of the protrusion. The tensioning roller is disposed below the protrusion and connected to the bridge-shaped platform. The two counterweight boxes are respectively disposed on the platform portions on both sides. Openings for a conveyor belt to pass through are provided on the bridge-shaped platform in the regions on either side of the protrusion. The tensioning bracket includes multiple vertically arranged guide posts. The bridge-shaped platform is provided with grooves or guide sleeves that cooperate with the multiple guide posts, allowing the counterweight device to be slidably mounted on the multiple guide posts via the grooves or guide sleeves. The non-contact displacement sensor... The device is mounted on the tensioning bracket to continuously monitor the real-time position of the counterweight and generate a position signal. The controller is signal-connected to the non-contact displacement sensor and pre-stores the upper and lower limits of the safe travel of the counterweight, as well as a reference position. The alarm is electrically connected to the controller, which is configured to perform the following operations: calculate the real-time offset of the counterweight relative to the reference position based on the position signal; compare the real-time offset with the upper and lower limits of the safe travel, and when the real-time offset exceeds either the upper or lower limit, control the alarm to issue a level one alarm; calculate the rate of change of the real-time offset per unit time, and when the rate of change continuously exceeds a preset normal fluctuation threshold, control the alarm to issue a level two alarm.

[0009] Furthermore, the controller is configured to: continuously acquire the real-time offset at a preset sampling frequency, and calculate the rate of change sequence of the real-time offset within a rolling preset time window; filter the rate of change sequence to eliminate instantaneous interference, and calculate the mean of the processed rate sequence as the rate of change; the controller also pre-stores a first rate threshold and a second rate threshold, the second rate threshold being greater than the first rate threshold; when the rate of change exceeds the first rate threshold but does not reach the second rate threshold, and this state continues for more than a first preset duration, it is determined to continuously exceed the normal fluctuation threshold, triggering the secondary alarm; when the rate of change instantaneously exceeds the second rate threshold, it is immediately determined to exceed the normal fluctuation threshold, triggering the secondary alarm.

[0010] Furthermore, it also includes: a pressure sensor, installed on the bearing seat of the tensioning roller, for real-time detection of the conveyor belt tension; a triaxial accelerometer, installed on the bridge-shaped platform, for acquiring vibration acceleration signals of the counterweight device in the X, Y, and Z axis directions; and a dual-axis tilt sensor, installed on the bridge-shaped platform, for monitoring the tilt angles of the bridge-shaped platform relative to the horizontal plane along the X and Y axes. The controller is connected to the pressure sensor, the triaxial accelerometer, and the dual-axis tilt sensor respectively, and is configured to perform the following operations: acquire the vibration acceleration signals at a preset period, perform Fourier transform on the time-domain signal of each period, and calculate the vibration energy values ​​of the X, Y, and Z axes within a preset frequency band as vibration spectrum characteristics; calculate the current comprehensive risk coefficient based on the tension force, the vibration spectrum characteristics, and the tilt angle; and control the alarm to issue a level three alarm when the comprehensive risk coefficient exceeds a risk threshold.

[0011] Furthermore, the formula for calculating the current comprehensive risk coefficient R by the risk assessment model is: R=(α×(F / F0)) 2 +β×(V / V0)+γ×(|θ X |+|θ Y |) / θ0)×(1+K×(1-e^(-t / τ)));where, F is the tension force, F0 is the preset reference value of the tension force; V is the current total vibration energy value, and its calculation formula is V 2 =(E X 2 +E Y 2 +E Z 2 E X E Y E Z These represent the vibration energy values ​​of the X, Y, and Z axes within a preset frequency band, respectively, with V0 being the vibration energy reference value; |θ X |、|θ Y | represents the absolute value of the tilt angle of the bridge-shaped platform in the X and Y directions, respectively; θ0 is the reference value of the tilt angle; α, β, and γ are the weighting coefficients of the tension force, the vibration energy value, and the tilt angle, respectively, and satisfy α+β+γ=1; t is the time during which the tension force F continuously exceeds the preset safe tension range; K is the time influence factor; τ is the time constant; and e is the natural constant.

[0012] Furthermore, the controller is configured to dynamically determine the risk threshold, including: continuously collecting and storing a historical comprehensive risk coefficient sequence {R} within a preset time period at preset intervals. i}, where i = 1, 2, ..., N; calculate the statistical benchmark value R of the historical comprehensive risk coefficient sequence. b Its calculation formula is R b =μ+kσ, where μ is the mean of the historical comprehensive risk coefficient sequence, σ is the standard deviation of the historical comprehensive risk coefficient sequence, and k is an adjustment coefficient; obtain the average operating speed V of the hammer device within the preset time length. avg And according to the average operating speed V avg Look up the corresponding baseline threshold R from the preset speed-threshold mapping table. t0 ; calculated using the dynamic risk threshold formula R threshold =max(R b ,R t0 )×(1+η·(|θ X |+|θ Y The dynamic risk threshold R is calculated by |) / (2θ0)). threshold Where η is the tilt influence factor.

[0013] Furthermore, it also includes a counterweight suspension mechanism, which includes a fixed rope wheel, a steel wire rope, and rope clamps; the fixed rope wheel is configured to be installed on a fixed foundation, the steel wire rope passes through the fixed rope wheel, and both ends are fixedly connected to the lifting lugs on both sides of the bridge-shaped platform by the rope clamps, and the steel wire rope is in a slack state.

[0014] Furthermore, the tensioning bracket includes four guide columns, and a ladder and a protective cage surrounding the ladder are also provided on the tensioning bracket. The protective cage is composed of alternating safety fences and maintenance fences, and the width of the maintenance fence is suitable for use as a maintenance platform for personnel to stop.

[0015] According to another aspect of the present invention, a control method for the vertical tensioning device is also provided, comprising: S1: continuously monitoring the real-time position of the counterweight device using a non-contact displacement sensor, and calculating its real-time offset and rate of change relative to a reference position by a controller; S2: comparing the real-time offset with a pre-stored safety travel limit; when the real-time offset exceeds the upper or lower limit of the safety travel limit, controlling an alarm to issue a level one alarm; when the rate of change continuously exceeds a preset normal fluctuation threshold, controlling an alarm to issue a level two alarm; S3: detecting the tension of the conveyor belt in real time using a pressure sensor, and collecting vibration signals and tilt angles of the counterweight device using a triaxial accelerometer and a dual-axis tilt sensor; S4: calculating the current comprehensive risk coefficient based on the tension, vibration signals, and tilt angles collected in step S3, according to a pre-stored risk assessment model; S5: dynamically determining the current risk threshold based on historical operating data and the real-time tilt angle; S6: comparing the comprehensive risk coefficient obtained in step S4 with the risk threshold determined in step S5; if the comprehensive risk coefficient exceeds the risk threshold, controlling an alarm to issue a level three alarm.

[0016] The present invention has at least the following beneficial effects:

[0017] The bridge-shaped platform of this invention integrates the tensioning roller and the double hammer box. The layout of the protrusion and the two side platforms allows the conveyor belt to pass through the reserved opening. Combined with the guiding structure of guide pillars and chutes / guide sleeves, it significantly reduces the horizontal and vertical space occupied while ensuring the tensioning function, making it suitable for space-constrained scenarios. Compared to traditional multi-set device solutions, the integrated design reduces the number of components, lowers equipment and maintenance costs, and offers a simpler structure and more convenient operation. Non-contact displacement sensors capture the position of the hammer device in real time. The controller calculates the offset and rate of change to achieve graded triggering of first and second level alarms, providing early warning of overtravel limits and abnormal fluctuations, preventing the escalation of faults.

[0018] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0019] Figure 1 This is a tensioning device in the existing technology;

[0020] Figure 2 This is a front view of a vertical tensioning device according to an embodiment of this application;

[0021] Figure 3 This is a left view of a vertical tensioning device according to an embodiment of this application;

[0022] Figure 4 This is a structural schematic diagram of a counterweight device and a counterweight suspension mechanism according to an embodiment of this application;

[0023] Figure 5 This is a schematic diagram of the structure of a counterweight device according to one embodiment of this application;

[0024] Figure 6 This is a logical framework diagram of one embodiment of this application. Detailed Implementation

[0025] The present invention will now be described in further detail so that those skilled in the art can implement it based on the description.

[0026] It should be understood that terms such as "having," "comprising," and "including" used in the embodiments of this application do not exclude the presence or addition of one or more other elements or combinations thereof. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of components in a specific posture. If the specific posture changes, the directional indication will also change accordingly. When an element is referred to as "fixed to" or "set on" another element, it can be directly on the other element or may have an intervening element present. When an element is referred to as "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element through an intervening element. Descriptions involving "first," "second," etc., in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0027] It should be noted that the technical solutions of the various embodiments of this application can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this application.

[0028] like Figure 1-5As shown, an embodiment of this application provides a vertical tensioning device, including a redirecting roller 1, a counterweight device 3, a tensioning bracket 4, a non-contact displacement sensor 6, a controller, and an alarm. The counterweight device 3 includes a bridge-shaped platform 13, a tensioning roller 8, and two counterweight boxes 15. The bridge-shaped platform 13 includes a protrusion in the middle and platform portions on both sides of the protrusion. The tensioning roller 8 is disposed below the protrusion and connected to the bridge-shaped platform 13. The two counterweight boxes 15 are respectively disposed on the platform portions on both sides. The bridge-shaped platform 13 has openings reserved on both sides of the protrusion for the conveyor belt to pass through. The tensioning bracket 4 includes multiple vertically arranged guide posts 10. The bridge-shaped platform 13 is provided with grooves or guide sleeves that cooperate with the multiple guide posts 10, so that the counterweight device 3 can be slidably disposed on the multiple guide posts 10 through the grooves or guide sleeves. The non-contact displacement sensor... Device 6 is mounted on the tensioning bracket 4 to continuously monitor the real-time position of the counterweight device 3 and generate a position signal; the controller is signal-connected to the non-contact displacement sensor 6, and the controller pre-stores the upper limit value, lower limit value, and reference position of the safe travel of the counterweight device 3; the alarm is electrically connected to the controller, and the controller is configured to perform the following operations: calculate the real-time offset of the counterweight device 3 relative to the reference position based on the position signal; compare the real-time offset with the upper limit value and the lower limit value of the safe travel, and when the real-time offset exceeds the upper limit value or the lower limit value of the safe travel, control the alarm to issue a first-level alarm; calculate the rate of change of the real-time offset per unit time, and when the rate of change continuously exceeds a preset normal fluctuation threshold, control the alarm to issue a second-level alarm.

[0029] For example, the vertical tensioning device is a key piece of equipment in the conveyor system for maintaining the tension of the conveyor belt. It includes a redirecting roller 1, a counterweight device 3, a tensioning bracket 4, a non-contact displacement sensor 6, a controller, and an alarm. The redirecting roller 1 and the bridge-shaped platform 13 are made of materials with high yield strength, providing a basic guarantee for the overall structural load-bearing capacity. The redirecting roller has a redirecting roller cover 2. The bridge-shaped platform 13 has a protrusion in the middle, which is not only used to install the tensioning roller 8, but also enhances the load-bearing capacity through structural optimization design. The height of the protrusion is 15-30cm. The two sides of the protrusion are platform sections for placing the counterweight box 15. This bridge-shaped structure with a "protrusion in the middle and gentle sides" makes the force more even, avoids stress concentration, and reserves sufficient vertical space for increasing the tensioning stroke. The tensioning roller 8 is covered with a rubber layer to increase the friction with the conveyor belt and is fixed directly below the protrusion by a cast iron bearing seat. A tensioning roller guard plate 14 is installed on the top of the tensioning roller. Two counterweight boxes 15 are placed on the platform section, each with a nitrile rubber anti-slip pad at the bottom. They are fixed to the platform section via pre-drilled bolt holes. This dual-box configuration increases the total counterweight mass without increasing horizontal space requirements, adapting to long-stroke tensioning needs. Simultaneously, the integrated welded structure of the platform section and the raised section allows the weight of the counterweight boxes 15 to be transferred to the entire bridge-shaped platform 13 through the platform section, preventing localized overload. Rectangular openings are provided on both sides of the raised section of the bridge-shaped platform 13 for the conveyor belt to pass through. This structure allows the conveyor belt to bypass the device, further reducing horizontal space requirements and maximizing the vertical space utilization of the tensioning bracket 4. Preferably, the bridge-shaped platform 13 can directly adopt a frame structure, thus eliminating the need for pre-drilled openings. The tensioning bracket 4 has two or four symmetrically arranged supports. The bottom is fixed to the concrete foundation by a 20mm thick pre-embedded steel plate. The guide columns 10 are reinforced by transverse connections with angle steel to enhance overall stability. The four corners of the bridge-shaped platform 13 are welded with steel guide sleeves that cooperate with the guide columns 10. The inner hole is clearance-fitted with the guide column 10, allowing the counterweight device 3 to slide smoothly along the guide column 10. The length of the guide column 10 should ensure sufficient vertical sliding stroke. The vertical guiding structure of the guide column 10 ensures that the counterweight tension is always vertically downward, providing a structural basis for tension stability. At the same time, it avoids the counterweight deviation from causing stroke obstruction. This is the core structural support for increasing the tensioning stroke of the device.

[0030] The weights in the two counterweight boxes 15 are fixed in mass, and the constant gravity they generate is transmitted to the tension roller 8 through the bridge platform 13, and then converted into the tension force of the conveyor belt. There is no power source involved in the entire force transmission path, and only gravity does the work. Therefore, the tension force will not fluctuate due to changes in stroke. The non-contact LK-G80 aluminum alloy displacement sensor is installed on the support beam. The 50cm detection interval and 10Hz sampling frequency can accurately capture the position of the platform. Its output 4-20mA signal is converted into a digital position value after AD conversion by the S7-200 PLC controller (installed in the side control cabinet). For example, the controller pre-stores a reference position of 2.5m, an upper limit of 3.5m (offset +1m), and a lower limit of 1.5m (offset -1m). Using the calculation logic of "real-time offset = real-time position value - reference position value," a 0.5m offset at a real-time position of 3m provides a clear indication of the travel status. When the offset reaches 1.2m or -1.1m, the controller activates the LTE-1101 ABS plastic alarm, emitting a continuous 85-decibel beep (Level 1 alarm). This is because exceeding the travel limit can lead to insufficient or excessive tension in the conveyor belt, and a timely alarm can prevent slippage or breakage. Simultaneously, the controller calculates the rate of change according to "change rate = (current offset - previous second offset) / 1 second," with a preset normal fluctuation threshold of 0.2m / s. Three consecutive exceedances of this threshold trigger an intermittent beep (Level 2 alarm). This is due to sudden changes in the offset rate (including rapid rises and falls exceeding the normal fluctuation range), such as sudden slack in the conveyor belt or malfunctions in the counterweight suspension mechanism. If such anomalies are not promptly alerted, they may lead to escalation of problems such as uncontrolled conveyor belt tension (slippage due to excessive looseness or breakage due to excessive tightness) and unstable impact from the counterweight. The design of the level-two alarm can quickly remind operators to investigate the anomaly and prevent the accident from escalating.

[0031] The existing double tension roller scheme relies on the "stroke multiplication" effect to achieve tension: the counterweight device has two built-in tension rollers and a complex supporting frame. When the device moves a distance S, the force transmission between the two rollers is amplified, enabling the conveyor belt to generate an effective tension stroke of 2S. This design, while seemingly improving stroke efficiency through principle innovation, actually comes at a significant structural cost—the parallel arrangement of the two rollers and the supporting frame greatly increases the structural height H1 of the counterweight device itself, becoming an incompressible "rigid space occupation." In contrast, the single tension roller 8 scheme in this embodiment returns to a simple 1:1 transmission logic: the counterweight device 3 integrates only one tension roller 8, achieving a compact layout through the "bridge-shaped platform 13"—the roller is fixed below the protrusion in the middle of the platform, and the two side platforms directly support the counterweight box 15, eliminating the redundant frame required for the double rollers, making the structural height H2 of the counterweight device 3 much smaller than the H1 of the existing technology. Although this design does not have a stroke multiplication effect, it eliminates the core space obstacle through structural optimization. When both are applied to scenarios where the total vertical installation space provided by the tension bracket 4 has a height of L, the difference in stroke becomes apparent. The total vertical installation space height L determines the maximum movable boundary of the counterweight device 3. In the prior art, the device's own height H1 occupies a large amount of installation space, and its actual movable distance is compressed to L-H1, resulting in a maximum effective tensioning stroke of 2×(L-H1). In this invention, the extremely small H2 hardly occupies any effective movable space, and the movable distance of the device is close to the entire length of the installation space, i.e., L-H2, and the corresponding effective tensioning stroke is L-H2. Moreover, the non-contact monitoring and hierarchical alarm logic can capture the precursors of failure from two dimensions: "position exceeding limits" and "abnormal rate," avoiding the lag of traditional solutions that rely solely on manual inspection. This significantly improves operational stability and effectively solves the contradiction between limited space and high cost.

[0032] In another embodiment, the controller is configured to: continuously acquire the real-time offset at a preset sampling frequency, and calculate the rate of change sequence of the real-time offset within a rolling preset time window; filter the rate of change sequence to eliminate instantaneous interference, and calculate the mean of the processed rate sequence as the rate of change; the controller also pre-stores a first rate threshold and a second rate threshold, the second rate threshold being greater than the first rate threshold; when the rate of change exceeds the first rate threshold but does not reach the second rate threshold, and this state continues for more than a first preset duration, it is determined to continuously exceed the normal fluctuation threshold, triggering the secondary alarm; when the rate of change instantaneously exceeds the second rate threshold, it is immediately determined to exceed the normal fluctuation threshold, triggering the secondary alarm.

[0033] For example, the controller is configured to process offset data according to specific logic, acquiring data at a sampling frequency of 50Hz. This frequency ensures the capture of minute offsets without increasing the controller's computational load due to excessive data volume. Fifty data points within a one-second rolling time window generate 49 rate-of-change values, forming a sequence that reflects the offset trend over a short period. The sequence is then filtered using a moving average of adjacent three points, such as filtering [0.1, 0.3, 0.2, 0.4] into [0.2, 0.3]. This processing can offset abnormal data caused by instantaneous conveyor belt jitter, as the peaks generated by jitter are diluted by the average of the preceding and following normal data, thus eliminating more than 80% of false alarms. The arithmetic mean of the filtered sequence is used as the final rate of change, making the result more closely resemble the actual operating state.

[0034] The controller pre-stores a first rate threshold of 0.15 m / s and a second rate threshold of 0.3 m / s. The core of the dual-threshold design is to distinguish between two scenarios: "continuous slow anomaly" and "instantaneous severe anomaly," accurately matching different equipment failure precursors. When the offset rate reaches 0.2 m / s (exceeding the first threshold but not the second threshold) and this state lasts for 5 seconds, it indicates that the counterweight is in a stable rapid offset state. Possible causes include gradual loosening of the conveyor belt and excessive fluctuations in the amount of material being conveyed. Triggering a secondary alarm at this time can provide operators with sufficient time for investigation and handling, preventing the anomaly from escalating further. When the offset rate suddenly changes to 0.35 m / s (exceeding the second threshold), it indicates that the equipment has experienced a sudden severe anomaly. Possible causes include loose or partially broken conveyor belt joints, sudden stress failure of the steel wire rope of the counterweight suspension mechanism, and unreasonable settings of the conveyor's start-up and braking parameters. This type of anomaly develops rapidly, and if not responded to immediately, it may lead to serious failures such as loss of tension control and counterweight instability. Therefore, a secondary alarm must be triggered immediately. Thresholds can be flexibly input via a human-machine interface and stored in non-volatile memory, ensuring that parameters are not lost after the device is powered off. The alarm system adopts a combination of "beep tone + indicator light" design. Alarms triggered by different thresholds can be distinguished by beep frequency (continuous beeping / intermittent beeping) or indicator light color, making it easy for operators to quickly identify the urgency of the anomaly and improving troubleshooting efficiency. The moving average filter in this embodiment removes interference from the data source, and the dual thresholds are matched to "continuous slow anomalies" and "sudden severe anomalies" respectively, making the alarm logic more in line with the fault development pattern. The 5-second continuous judgment condition avoids accidental triggering due to occasional fluctuations, while the instantaneous over-limit alarm ensures rapid response in emergencies. The monitoring accuracy and reliability are significantly improved, solving the problem of the one-sidedness of traditional monitoring.

[0035] In another embodiment, the system further includes: a pressure sensor mounted on the bearing seat of the tensioning roller 8 for real-time detection of the conveyor belt tension; a triaxial accelerometer mounted on the bridge platform 13 for acquiring vibration acceleration signals of the counterweight device 3 in the X, Y, and Z axes; and a dual-axis tilt sensor mounted on the bridge platform 13 for monitoring the tilt angles of the bridge platform 13 relative to the horizontal plane along the X and Y axes. The controller is connected to the pressure sensor, the triaxial accelerometer, and the dual-axis tilt sensor, and is configured to perform the following operations: acquire the vibration acceleration signals at a preset period; perform Fourier transform on the time-domain signal of each period to calculate the vibration energy values ​​of the X, Y, and Z axes within a preset frequency band, as vibration spectrum characteristics; calculate the current comprehensive risk coefficient based on the tension force, the vibration spectrum characteristics, and the tilt angle; and control the alarm to issue a level three alarm when the comprehensive risk coefficient exceeds a risk threshold.

[0036] For example, the device adds pressure, triaxial acceleration, and biaxial tilt sensors to achieve multi-dimensional monitoring. A stainless steel pressure sensor is installed in the bearing housing of the tension roller 8. The probe, in contact with the force-bearing surface, can directly capture the radial force borne by the bearing housing, which is then converted into conveyor belt tension, as the pressure of the tension roller 8 is linearly related to the conveyor belt tension. An aluminum alloy triaxial acceleration sensor is fixed to the protrusion of the bridge-shaped platform 13. With the X-axis along the conveyor belt direction, the Y-axis horizontally perpendicular to the X-axis, and the Z-axis vertically upward, it can capture vibrations in the conveyor belt's running direction, lateral direction, and vertical direction, respectively. A 100Hz sampling frequency and a ±16g range accurately record mechanical vibration characteristics. A biaxial tilt sensor is installed on the platform. With a ±10° range and 0.01° accuracy, it can monitor platform tilt, as tilting of the bridge-shaped platform 13 can cause uneven loading of the counterweight and conveyor belt deviation, affecting tension stability. The controller receives sensor data through a multi-channel module, collects vibration signals every 2 seconds, performs FFT transformation, and extracts energy in the 1-10Hz frequency band. This band contains typical vibration characteristics of mechanical faults in the equipment; for example, bearing wear can cause an increase in vibration energy at a specific frequency. A comprehensive risk coefficient is calculated by combining tension (reflecting the stress state), vibration energy (reflecting mechanical stability), and tilt angle (reflecting structural balance). When the coefficient exceeds a threshold of 1.5, a level-three alarm is triggered. This is because a single parameter anomaly may be an occasional occurrence, while a comprehensive anomaly of multiple parameters often indicates a serious fault and requires priority handling.

[0037] In existing technologies, monitoring only displacement or other single indicators cannot detect potential risks such as abnormal tension or excessive vibration, often leading to equipment damage due to the failure to detect hidden dangers in time. The multi-sensor fusion scheme in this embodiment constructs a risk assessment system from three dimensions: force, vibration, and structure, overcoming the limitations of single-parameter monitoring. By converting time-domain vibration signals into frequency-domain features through FFT transformation, it can identify early signs of failure such as mechanical wear, significantly improving equipment operational safety.

[0038] In another embodiment, the risk assessment model calculates the current comprehensive risk coefficient R using the following formula:

[0039] R=(α×(F / F0) 2 +β×(V / V0)+γ×(|θ X |+|θ Y |) / θ0)×(1+K×(1-e^(-t / τ))), where F is the tension force, F0 is the preset reference value of the tension force; V is the current total vibration energy value, and its calculation formula is V 2 =(E X 2 +E Y 2 +E Z 2 E X E Y E Z These represent the vibration energy values ​​of the X, Y, and Z axes within a preset frequency band, respectively, with V0 being the vibration energy reference value; |θ X |、|θ Y | represents the absolute value of the tilt angle of the bridge platform 13 in the X and Y directions, respectively; θ0 is the reference value of the tilt angle; α, β, and γ are the weighting coefficients of the tension force, the vibration energy value, and the tilt angle, respectively, and satisfy α+β+γ=1; t is the time during which the tension force F continuously exceeds the preset safe tension range; K is the time influence factor; τ is the time constant; and e is the natural constant.

[0040] For example, in the risk assessment model, the weighting coefficients α=0.4, β=0.3, and γ=0.3 are set based on the degree of influence of each parameter on equipment risk. Abnormal tension directly determines whether the conveyor belt slips or breaks, and has the greatest impact, hence its highest weight; vibration and tilt indirectly reflect the equipment condition, with their weights decreasing in that order. The squared term of the ratio of the measured tension (e.g., F=30kN) to the benchmark value (F0=25kN) is because the impact of tension on risk is non-linear; the greater the deviation from the benchmark value, the faster the risk increases. The ratio of the total vibration energy V (e.g., 7.07) to V0 (benchmark value, e.g., 5) reflects that the higher the vibration energy, the greater the risk; (|θ X |+|θ YThe ratio of |)=0.8° to θ0=2° reflects that the larger the tilt angle, the more unstable the structure. The exponential term with time influence factor K=0.2 and time constant τ=10, when t=0 (tension force within the safe range of 20-40kN), e^0=1, and this part is 1.2. If t increases, e^(-t / τ) decreases, and the time influence weakens. This is because when the tension force just exceeds the safe range, the equipment has short-term tolerance; the risk only increases significantly over time, which is consistent with the development law of equipment failure. Substituting the data for calculation: Part 1: 0.4×(30 / 25) 2 +0.3×(7.07 / 5)+0.3×(0.8 / 2)=0.4×1.44+0.3×1.414+0.3×0.4=1.1202, Part 2 (t=10s): 1+0.2×0.632=1.1264, and finally R≈1.261. This result comprehensively reflects the multi-dimensional risk status of the current equipment.

[0041] In existing technologies, risk assessment often relies on a single parameter, such as displacement alone, which fails to reflect the overall condition of the equipment and results in a one-sided assessment. This embodiment's model highlights key risk factors through weighted allocation, and its nonlinear and time terms align with actual risk patterns, avoiding the crude assessment method of simply superimposing parameters. The calculation results accurately map the actual risk of the equipment, providing a scientific basis for alarm triggering and solving the problem of traditional assessments being disconnected from actual faults.

[0042] In another embodiment, the controller is configured to dynamically determine the risk threshold, including: continuously collecting and storing a historical comprehensive risk coefficient sequence {R} within a preset time period at preset intervals. i}, where i = 1, 2, ..., N; calculate the statistical benchmark value R of the historical comprehensive risk coefficient sequence. b Its calculation formula is R b =μ+kσ, where μ is the mean of the historical comprehensive risk coefficient sequence, σ is the standard deviation of the historical comprehensive risk coefficient sequence, and k is an adjustment coefficient; obtain the average operating speed V of the hammer device 3 within the preset time length. avg And according to the average operating speed V avg Look up the corresponding baseline threshold R from the preset speed-threshold mapping table. t0 ; calculated using the dynamic risk threshold formula R threshold =max(R b ,R t0 )×(1+η·(|θ X |+|θ Y The dynamic risk threshold R is calculated by |) / (2θ0)). threshold Where η is the tilt influence factor.

[0043] For example, the controller collects 1 hour of historical data at 5-minute intervals to form 12 {R} i The calculated mean μ≈1.125 and standard deviation σ≈0.103, with an adjustment factor of k=2, make the statistical baseline value Rb=1.125+2×0.103≈1.331—this value covers more than 95% of the normal operation risk range, avoiding alarms triggered by normal fluctuations. The average speed V of the weighted hammer. avg =0.05m / s (displacement of 180 meters in 1 hour) corresponds to R t0 =1.4, because the lower the operating speed, the smaller the equipment inertia, and the risk threshold can be appropriately increased. The tilt influence factor η=0.5 in the dynamic threshold formula is obtained through (|θ X |+|θ Y The tilt correction term is calculated using |) / (2θ0) because a larger tilt angle results in poorer equipment stability, necessitating a lower threshold to improve alarm sensitivity. Substituting the data yields R. threshold =max(1.331,1.4)×(1+0.5×0.8 / (4))=1.4×1.1=1.54. This threshold takes into account both the normal range of historical operation and the current tilt state, and is more in line with the real-time working conditions than a fixed threshold.

[0044] In existing technologies, risk thresholds are mostly fixed values, which are prone to false alarms when the equipment is running at low speeds and prone to missed alarms when running at high speeds or tilted. The dynamic threshold in this embodiment determines the basic range through historical data statistics and combines real-time speed and tilt state corrections, allowing the threshold to adaptively adjust according to changes in operating conditions. Alarm accuracy is significantly improved, avoiding unnecessary downtime while ensuring no real risks are missed, thus solving the adaptability problem of fixed thresholds.

[0045] In another embodiment, a counterweight suspension mechanism 7 is also included, which includes a fixed rope wheel 16, a steel wire rope 17, and a rope clamp 18. The fixed rope wheel 16 is configured to be installed on a fixed foundation, the steel wire rope 17 passes through the fixed rope wheel 16, and its two ends are respectively fixedly connected to the lifting lugs on both sides of the bridge-shaped platform 13 by the rope clamp 18, and the steel wire rope 17 is in a slack state.

[0046] For example, the cast steel fixed rope pulley 16 of the counterweight suspension mechanism 7 is installed on the top foundation of the support. Its single-groove structure is adapted to carbon steel wire rope 17. The axis of the rope pulley 16 is aligned with the width direction of the platform to ensure the force balance of the wire rope 17. The length of the wire rope 17 is 1 meter longer than the maximum sliding distance of the counterweight. Both ends are fixed to the platform lifting lugs with steel rope clamps 18 (e.g., 3, determined according to the diameter of the wire rope). The multiple rope clamps 18 can distribute the tension and prevent excessive force at a single point from causing it to fall. After installation, the wire rope 17 is 50cm longer than the lowest safe position of the counterweight. During normal operation, it is slack and not under force because if the wire rope 17 is taut, it will offset the tension of the counterweight and affect the tension adjustment. In the event of an abnormal fall, the wire rope 17 is straightened and under force, and the tension is transmitted to the fixed foundation through the rope pulley 16, which can prevent the counterweight from falling further and avoid impacting the ground, causing equipment damage or safety accidents.

[0047] In existing technologies, most counterweight devices 3 lack auxiliary suspension structures. When sudden situations occur, such as failure of the counterweight connection structure or breakage of the conveyor belt, the counterweight lacks secondary protective restraint and is prone to falling, potentially causing serious accidents. The suspension mechanism in this embodiment adopts a design logic of "normal relaxation, abnormal force," which neither interferes with the normal operation of the equipment nor fails to provide dual protection in case of sudden malfunctions. Its structure is simple, and the selected pulley 16 and wire rope 17 are mature components, requiring no additional maintenance costs and solving the safety protection deficiencies of traditional devices.

[0048] In another embodiment, the tensioning bracket 4 includes four guide posts 10, and a ladder 11 and a protective cage 12 surrounding the ladder 11 are also provided on the tensioning bracket 4. The protective cage 12 is composed of alternating safety fences and maintenance fences, and the width of the maintenance fence is suitable for use as a maintenance platform for personnel to stop.

[0049] For example, the four guide posts 10 of the tensioning bracket 4 are reinforced by horizontal connections with angle steel, which enhances overall stability and prevents the guide posts 10 from bending under stress. The ladder beams and round steel steps (spaced 30cm apart) of the angle steel ladder 11 extend from the ground to the top, conforming to ergonomics and facilitating climbing by maintenance personnel. The 80cm diameter steel cage 12 outside the ladder 11 consists of alternating safety and maintenance fences, with an 80cm wide maintenance fence section installed every 3 meters. During maintenance, personnel can stand on it to operate without the need for scaffolding, as the width of the maintenance fence meets the standing requirements of the human body. The spacing of the steps is consistent with that of the ladder 11 to ensure stable footing. The cage 12 is welded and fixed to the ladder 11, making the overall structure sturdy and reliable. Movable guardrails 5 are also installed around the tensioning bracket.

[0050] In existing technologies, the tensioning support 4 and ladder 11 are often simple without a safety cage 12, requiring scaffolding for maintenance, which is not only time-consuming (1-2 hours to set up) but also has poor stability and poses safety hazards. In this embodiment, the safety cage 12 ensures safety during the climbing process, and the maintenance fence directly provides an operating platform, shortening maintenance time and avoiding the cost and risks of scaffolding construction, thus improving the convenience and safety of maintenance.

[0051] like Figure 6 As shown, embodiments of this application also provide a vertical tensioning device control method, including:

[0052] S1: The real-time position of the counterweight device 3 is continuously monitored by the non-contact displacement sensor 6, and the controller calculates its real-time offset and rate of change relative to the reference position.

[0053] S2: Compare the real-time offset with the pre-stored safe travel limit. When the real-time offset exceeds the upper or lower limit of the safe travel, the alarm will issue a first-level alarm. When the rate of change continues to exceed the preset normal fluctuation threshold, the alarm will issue a second-level alarm.

[0054] S3: The tension of the conveyor belt is detected in real time by a pressure sensor, and the vibration signal and tilt angle of the counterweight device 3 are collected by a triaxial accelerometer and a dual-axis tilt sensor.

[0055] S4: Based on the tension force, vibration signal and tilt angle collected in step S3, calculate the current comprehensive risk coefficient according to the pre-stored risk assessment model;

[0056] S5: Dynamically determine the current risk threshold based on historical operating data and real-time tilt angle;

[0057] S6: Compare the comprehensive risk coefficient obtained in step S4 with the risk threshold determined in step S5. If the comprehensive risk coefficient exceeds the risk threshold, control the alarm to issue a level three alarm.

[0058] The control method features tightly integrated steps. In S1, six non-contact displacement sensors sample at 10Hz and calculate in real-time with the controller, ensuring the timeliness of offset and rate data. This is the foundation for subsequent judgments; data lag will lead to alarm delays. In S2, the first-level alarm targets overtravel, as the conveyor belt tension has deviated from the safe range and requires immediate attention. The second-level alarm targets abnormal speed, providing early warning of potential jamming faults, forming a dual guarantee of addressing current problems and preventing future failures. In S3, multiple sensors collect data synchronously: pressure sensors sample every 0.5 seconds to ensure real-time updates of tension, acceleration sensors sample at 100Hz to capture vibration details, and tilt sensors sample every 0.1 seconds to monitor structural balance. This multi-dimensional data provides support for comprehensive evaluation. In S4, FFT transformation converts the vibration time-domain signal into frequency-domain features, making the vibration patterns of mechanical faults easier to identify. Combined with tension and tilt angle calculations, the risk coefficient is calculated, achieving an improvement from single-parameter monitoring to comprehensive risk assessment. In S5, the dynamic threshold combines historical data with real-time status to ensure its adaptability. In S6, the risk coefficient is compared with the dynamic threshold; triggering a Level 3 alarm indicates a serious comprehensive risk to the equipment, requiring priority investigation. The entire process forms a closed loop from data collection and analysis to alarm triggering, with logical progression at each level.

[0059] In existing technologies, control methods only monitor displacement, resulting in single alarms, delayed fault response, and ambiguous fault location. The control method in this embodiment expands the monitoring dimensions from "location" to "force, vibration, and structure" through multi-parameter acquisition, tiered alarms, and dynamic evaluation. Alarm levels differentiate fault severity, enabling operators to quickly prioritize problems. The closed-loop design of the process ensures that the output of each stage provides a basis for the next stage, improving the reliability and intelligence of equipment control.

[0060] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and embodiments shown and described herein.

Claims

1. A vertical tensioning device, characterized in that, It includes a redirecting roller, a counterweight device, a tensioning bracket, a non-contact displacement sensor, a controller, and an alarm. The counterweight device includes a bridge-shaped platform, a tensioning roller, and two counterweight boxes. The bridge-shaped platform includes a protrusion in the middle and platform sections on both sides of the protrusion. The tensioning roller is located below the protrusion and connected to the bridge-shaped platform. The two counterweight boxes are respectively located on the platform sections on both sides. The bridge-shaped platform has openings reserved on both sides of the protrusion for the conveyor belt to pass through. The tensioning bracket includes multiple vertically arranged guide columns, and the bridge-shaped platform is provided with a sliding groove or guide sleeve that cooperates with the multiple guide columns, so that the counterweight device can be slidably mounted on the multiple guide columns through the sliding groove or guide sleeve; The non-contact displacement sensor is mounted on the tensioning bracket to continuously monitor the real-time position of the counterweight device and generate a position signal. The controller is connected to the non-contact displacement sensor, and the controller has pre-stored the upper limit of the safe stroke, the lower limit of the safe stroke, and the reference position of the counterweight device. The alarm is electrically connected to the controller, which is configured to perform the following operations: calculate the real-time offset of the counterweight relative to the reference position based on the position signal; compare the real-time offset with the upper limit and lower limit of the safe travel range; when the real-time offset exceeds the upper limit or lower limit of the safe travel range, control the alarm to issue a level one alarm; calculate the rate of change of the real-time offset per unit time; when the rate of change continuously exceeds a preset normal fluctuation threshold, control the alarm to issue a level two alarm. It also includes: a pressure sensor, which is installed on the bearing seat of the tensioning roller, for real-time detection of the tension of the conveyor belt; A triaxial accelerometer is mounted on the bridge-shaped platform to collect vibration acceleration signals of the weight device in the X, Y, and Z axes. A biaxial tilt sensor is mounted on the bridge-shaped platform to monitor the tilt angles of the bridge-shaped platform relative to the horizontal plane along the X and Y axes. The controller is connected to the pressure sensor, triaxial accelerometer, and biaxial tilt sensor respectively and is configured to perform the following operations: collect the vibration acceleration signals at a preset period; perform Fourier transform on the time-domain signal of each period to calculate the vibration energy values ​​of the X, Y, and Z axes within a preset frequency band as vibration spectrum characteristics; calculate the current comprehensive risk coefficient based on the tension force, the vibration spectrum characteristics, and the tilt angle; and control the alarm to issue a level three alarm when the comprehensive risk coefficient exceeds a risk threshold.

2. The vertical tensioning device as described in claim 1, characterized in that, The controller is configured to: The real-time offset is continuously acquired at a preset sampling frequency, and the rate of change sequence of the real-time offset is calculated within a rolling preset time window; The rate of change sequence is filtered to eliminate instantaneous interference, and the mean of the processed rate sequence is calculated as the rate of change. The controller also has a first rate threshold and a second rate threshold pre-stored, and the second rate threshold is greater than the first rate threshold. When the rate of change exceeds the first rate threshold but does not reach the second rate threshold, and this state continues for more than the first preset time, it is determined that the normal fluctuation threshold is continuously exceeded, and the second-level alarm is triggered. When the rate of change instantaneously exceeds the second rate threshold, it is immediately determined that the normal fluctuation threshold has been exceeded, and the secondary alarm is triggered.

3. The vertical tensioning device as described in claim 1, characterized in that, The formula for calculating the current comprehensive risk coefficient R by the risk assessment model is as follows: R=(α×(F / F0) 2 +β×(V / V0)+γ×(|θ X |+|θ Y |) / θ0)×(1+K×(1-e^(-t / τ))) Where F is the tension force, F0 is the preset reference value of the tension force; V is the current total vibration energy value, and its calculation formula is V 2 =(E X 2 +E Y 2 +E Z 2 E X E Y E Z These represent the vibration energy values ​​of the X, Y, and Z axes within a preset frequency band, respectively, with V0 being the vibration energy reference value; |θ X |、|θ Y | represents the absolute value of the tilt angle of the bridge-shaped platform in the X and Y directions, respectively; θ0 is the reference value of the tilt angle; α, β, and γ are the weighting coefficients of the tension force, the vibration energy value, and the tilt angle, respectively, and satisfy α+β+γ=1; t is the time during which the tension force F continuously exceeds the preset safe tension range; K is the time influence factor; τ is the time constant; and e is the natural constant.

4. The vertical tensioning device as described in claim 1, characterized in that, The controller is configured to dynamically determine the risk threshold, including: continuously collecting and storing a historical comprehensive risk coefficient sequence {R} within a preset time period at preset intervals. i }, where i = 1, 2, ..., N; calculate the statistical benchmark value R of the historical comprehensive risk coefficient sequence. b Its calculation formula is R b =μ+kσ, where μ is the mean of the historical comprehensive risk coefficient sequence, σ is the standard deviation of the historical comprehensive risk coefficient sequence, and k is an adjustment coefficient; obtain the average operating speed V of the hammer device within the preset time length. avg And according to the average operating speed V avg Look up the corresponding baseline threshold R from the preset speed-threshold mapping table. t0 ; calculated using the dynamic risk threshold formula R threshold =max(R b ,R t0 )×(1+η·(|θ X |+|θ Y The dynamic risk threshold R is calculated by |) / (2θ0)). threshold Where η is the tilt influence factor.

5. The vertical tensioning device as described in claim 1, characterized in that, It also includes a counterweight suspension mechanism, which includes a fixed rope pulley, a wire rope, and a rope clamp; The fixed rope pulley is configured to be installed on a fixed foundation. The wire rope passes through the fixed rope pulley, and its two ends are respectively fixedly connected to the lifting lugs on both sides of the bridge-shaped platform by the rope clamps. The wire rope is in a slack state.

6. The vertical tensioning device according to claim 1, characterized in that, The tensioning bracket includes four guide columns, and a ladder and a protective cage surrounding the ladder are also installed on the tensioning bracket. The protective cage is composed of alternating safety fences and maintenance fences, and the width of the maintenance fence is suitable for use as a maintenance platform for personnel to stop.

7. The vertical tensioning device control method as described in claim 1, characterized in that, include: S1: The real-time position of the counterweight device is continuously monitored by a non-contact displacement sensor, and the controller calculates its real-time offset and rate of change relative to the reference position. S2: Compare the real-time offset with the pre-stored safe travel limit. When the real-time offset exceeds the upper or lower limit of the safe travel, the alarm will issue a first-level alarm. When the rate of change continues to exceed the preset normal fluctuation threshold, the alarm will issue a second-level alarm. S3: The tension of the conveyor belt is detected in real time by a pressure sensor, and the vibration signal and tilt angle of the counterweight device are collected by a triaxial accelerometer and a dual-axis tilt sensor. S4: Based on the tension force, vibration signal and tilt angle collected in step S3, calculate the current comprehensive risk coefficient according to the pre-stored risk assessment model; S5: Dynamically determine the current risk threshold based on historical operating data and real-time tilt angle; S6: Compare the comprehensive risk coefficient obtained in step S4 with the risk threshold determined in step S5. If the comprehensive risk coefficient exceeds the risk threshold, control the alarm to issue a level three alarm.

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