Motion monitoring control method and system for telescopic rod of die roller gap adjusting mechanism

Abstract

The invention discloses a method and a system for monitoring and controlling motion of a telescopic rod of a die roller gap adjusting mechanism. The available stroke of the telescopic rod is converted into the residual rotating capacity of the pneumatic motor in the extending and shortening directions, and real-time monitoring of the motion state of the telescopic rod and basic stroke protection are achieved. On the basis, a prediction mechanism based on the motion trend is further introduced, future displacement of the telescopic rod under the action of control response delay and pneumatic inertia is predicted, a stroke risk assessment model is constructed, and the pneumatic driving capacity is adaptively adjusted according to a prediction result; the telescopic rod is gradually decelerated and enters a controlled state before approaching the travel limit, and forced protection is executed in time when a border crossing risk is predicted to exist. By means of the mode, overtravel operation of the telescopic rod and mechanical impact and structural damage caused by the overtravel operation can be effectively avoided, and on the premise that complex hardware structures are not added, safety, stability and reliability in the die roller gap adjusting process are improved.

Description

Technical Field

[0001] This invention belongs to the field of pelleting equipment control technology, and particularly relates to a method and system for monitoring and controlling the movement of the telescopic rod of a die roller gap adjustment mechanism. Background Technology

[0002] In pelleting equipment and related processing gear, the die roller gap adjustment mechanism is one of the crucial basic components that directly affects pelleting quality, energy consumption, and stable equipment operation. The gap between the ring die and the pressure roller not only determines the uniformity and density of the material under pressure, but also relates to several key performance indicators such as die wear, energy consumption fluctuations, and equipment operating noise. Therefore, in actual production, the die roller gap often needs to be frequently and precisely adjusted according to material characteristics, process conditions, and equipment wear status, which places higher demands on the control precision, safety, and reliability of the die roller gap adjustment mechanism.

[0003] Existing mold roller gap adjustment mechanisms typically use pneumatic motors as power sources, driving the telescopic rod to extend or retract via threaded pairs, gear pairs, or linkage mechanisms to adjust the mold roller position. This type of structure offers advantages such as high output force, relatively simple structure, and strong adaptability to various working conditions, making it widely used in practical engineering. However, due to the inherent characteristics of pneumatic drives—such as slow response, difficulty in fine-tuning output, and significant inertia—if improper control is applied when the adjustment mechanism approaches its stroke limit, the telescopic rod may exceed its designed stroke range. This can lead to deformation of transmission components, damage to the limit structure, or even complete machine failure, severely impacting the equipment's lifespan and operational safety.

[0004] To prevent telescopic booms from overtraveling, existing technologies generally limit their range of motion by using mechanical limit structures or travel stops. However, this purely mechanical limiting method has limited buffering and energy absorption capabilities when faced with continuous pneumatic motor supply or high load conditions. Once the pneumatic motor's output torque exceeds the limit structure's load-bearing capacity, it may still jam and force operation, failing to provide effective protection and easily causing rapid wear or failure of the limit structure itself. Furthermore, mechanical limits typically only function at the end of the stroke and cannot adjust the motion state near the limit, making it difficult to avoid shocks and vibrations caused by sudden stops.

[0005] Some improved solutions employ electrical control to limit the operation of pneumatic motors, but these mostly focus on static judgments of whether limits have been reached, lacking effective analysis of the current movement trend of the telescopic boom and making it difficult to distinguish between different risk states approaching limits. For example, when the telescopic boom approaches the end of its stroke at a higher speed, its potential risk is obviously higher than at low speeds. However, traditional control methods typically cannot identify and respond to this difference, resulting in control strategies that are either too conservative, affecting adjustment efficiency, or have a delayed response, making it difficult to guarantee safety. Furthermore, due to the lack of flexible adjustment methods for the process of approaching limits, existing solutions often directly cut off the drive when the protective action is triggered, which can easily lead to shock, noise, and component fatigue problems. Long-term use is detrimental to the stability and durability of the adjustment mechanism.

[0006] Therefore, how to monitor and control the motion state of the telescopic rod in the roller gap adjustment mechanism more precisely and reliably without significantly increasing system complexity and hardware costs, and how to identify risks and take effective intervention measures in time before the telescopic rod approaches its stroke limit, so as to avoid overtravel operation and reduce mechanical impact, has become one of the technical problems that urgently need to be solved in this field. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the present invention provides a method and system for monitoring and controlling the movement of the telescopic rod of a mold roller gap adjustment mechanism, the specific technical solution of which is as follows: A method for monitoring and controlling the movement of the telescopic rod of a mold roller gap adjustment mechanism, comprising the following steps: Obtain the initial position parameters of the telescopic rod in the mold roller gap adjustment mechanism; Set or determine the travel limit positions of the telescopic rod in the extension and retraction directions; Based on the initial position parameters and the travel limit position, calculate the travel margin of the telescopic rod in its direction of movement; Based on the transmission ratio between the telescopic rod and the pneumatic motor, the stroke margin is converted into the remaining number of rotations of the pneumatic motor in the corresponding rotation direction; The number of rotations of the pneumatic motor is collected in real time during the movement of the telescopic rod, and the remaining number of rotations corresponding to the direction of movement of the telescopic rod is dynamically updated based on the number of rotations and the direction of rotation. When the remaining number of rotations of the pneumatic motor in a certain direction decreases to zero, the air supply is immediately cut off to prevent the pneumatic motor from continuing to rotate in that direction, thereby limiting the telescopic rod from continuing to move in that direction to avoid overtravel.

[0008] Preferably, the pneumatic motor is equipped with a corresponding pulse sensor, and a pulse signal is acquired for each rotation of the pneumatic motor drive shaft, thereby realizing the real-time acquisition of the number of rotations of the pneumatic motor and the real-time update of the remaining number of rotations.

[0009] Furthermore, the method also includes a telescopic pole motion trend prediction and adaptive suppression mechanism: S1. During the movement of the telescopic rod, the equivalent displacement of the telescopic rod is determined in real time according to the number of rotations of the pneumatic motor, and the motion trend parameters of the telescopic rod are obtained based on the equivalent displacement and its relationship with time. S2. Based on the motion trend parameters, predict the future displacement of the telescopic rod within a preset prediction time window, and generate a travel risk parameter characterizing the telescopic rod approaching the travel limit position based on the distance between the predicted displacement and the travel limit position corresponding to the current motion direction. S3. Based on the aforementioned stroke risk parameters, the driving force of the pneumatic motor is adaptively adjusted so that the telescopic rod gradually reduces its movement speed before approaching the stroke limit position. S4. When the predicted displacement reaches or exceeds the travel limit position in the corresponding direction, the air supply to the pneumatic motor in that direction is cut off to prevent the telescopic rod from continuing to move in that direction.

[0010] Further, in step S1, the equivalent displacement is expressed as:

[0011] in, and These represent the time intervals of the telescopic pole. and The equivalent displacement. The sampling period is for the number of rotations of the pneumatic motor; This represents the increment of the number of rotations within the sampling period, and The value is positive when the telescopic pole extends and negative when it retracts. k The transmission ratio between the telescopic rod and the pneumatic motor represents the change in the length of the telescopic rod corresponding to one revolution of the pneumatic motor drive shaft. The motion trend parameters include the speed and acceleration of the telescopic pole: ,

[0012] in, and These represent the time intervals of the telescopic pole. and The speed of movement, For the telescopic pole at any time The acceleration.

[0013] Further, in step S2, the predicted displacement is expressed as:

[0014] in, Indicates time The predicted displacement; To predict the width of the time window, we have:

[0015] in, This refers to the electrical control response time of the solenoid valve. This refers to the gas path pressure decay time. This is the equivalent mechanical inertia delay time for pneumatic motors and telescopic rod transmission mechanisms.

[0016] Furthermore, the width of the prediction time window is adaptively set according to the operating state of the telescopic boom:

[0017] in, for The width of the prediction time window at time. Based on response time, The speed weighting coefficient is used; in high-speed adjustment mode, the prediction time window automatically increases, thereby enhancing safety; in low-speed fine-tuning mode, the prediction time window decreases accordingly to improve control sensitivity and adjustment efficiency.

[0018] Further, in step S2, the trip risk parameter is expressed as:

[0019] in, R This represents the trip's risk value. This is the risk sensitivity coefficient, used to adjust the rate at which risk increases with distance; d safe A pre-set safety buffer distance; Indicates the travel limit position corresponding to the predicted displacement and the current direction of motion. The distance between them.

[0020] Furthermore, in step S3, based on the trip risk value... R The solenoid valve's drive duty cycle is adaptively adjusted so that the driving force gradually decreases as the risk increases:

[0021] in, Indicates time t The solenoid valve's airflow duty cycle within the specified period. The normal duty cycle is used to control the solenoid valve in a pulse manner according to the duty cycle within one cycle. This reduces the air supply and drive when the telescopic rod is close to its stroke limit, thereby allowing the telescopic rod to decelerate automatically and reducing the probability of inertial impact and exceeding the limit.

[0022] A telescopic pole motion monitoring and control system based on the above method, the system mainly includes the following modules: The signal acquisition unit is used to acquire the rotation status information of the pneumatic motor in real time during operation and generate a rotation pulse signal corresponding to the number of rotations of the pneumatic motor. The parameter calculation unit is used to calculate the travel margin of the telescopic rod in the extension direction and the shortening direction according to the input initial position parameters of the telescopic rod, and convert the travel margin into the remaining number of rotations of the pneumatic motor in the corresponding direction based on the transmission ratio relationship between the pneumatic motor and the telescopic rod. The stroke monitoring and control unit is communicatively connected to the signal acquisition unit and the parameter calculation unit. During the operation of the pneumatic motor, it updates the remaining number of rotations corresponding to the extension direction and the shortening direction in real time according to the rotation pulse signal and the rotation direction of the pneumatic motor, and determines whether the remaining number of rotations has reached the preset lower limit condition. The drive execution unit is connected to the stroke monitoring and control unit and to the air source control circuit of the pneumatic motor. When the stroke monitoring and control unit determines that the remaining number of rotations of the pneumatic motor in a certain direction has reached a preset lower limit, it controls the solenoid valve corresponding to the direction of the pneumatic motor to stop supplying air, so as to prevent the pneumatic motor from continuing to rotate in that direction, thereby limiting the telescopic rod from continuing to move in that direction. The human-machine interaction unit is used to output an alarm prompt when the remaining number of rotations reaches a preset lower limit condition, and is also used to receive the initial position parameters and control commands of the telescopic rod input by the user.

[0023] Furthermore, the travel monitoring and control unit also includes a motion state analysis module, a position prediction module, and a travel risk assessment module; the motion state analysis module is used to determine the current equivalent displacement state of the telescopic rod based on the rotation pulse signal, and to obtain the motion trend parameters of the equivalent displacement state changing over time; the position prediction module is used to predict the future displacement of the telescopic rod within a preset prediction time window based on the equivalent displacement state and the motion trend parameters; the travel risk assessment module is used to generate travel risk parameters characterizing the telescopic rod approaching its travel limit position based on the distance between the predicted displacement and the travel limit position corresponding to the current motion direction. The drive actuator is also used to adaptively adjust the driving force of the pneumatic motor according to the stroke risk parameter, so that the telescopic rod gradually reduces its movement speed before approaching the stroke limit position, and cuts off the air supply of the pneumatic motor in the corresponding direction when the predicted displacement reaches or exceeds the stroke limit position.

[0024] Compared with the prior art, the present invention has at least the following beneficial effects: Compared to existing roller gap adjustment mechanisms that primarily rely on mechanical limits or single electrical stop control, this invention first converts the remaining stroke of the telescopic rod into the remaining number of rotations of the pneumatic motor, and updates and limits this number of rotations in real time during operation. This eliminates the need for the adjustment mechanism to rely entirely on end-effector mechanical limits to mitigate the risk of overtravel. Instead, the control system constrains the telescopic rod's range of motion at the software level, effectively reducing the problem of the telescopic rod being forcibly jammed and transmission components being damaged due to continuous air supply and excessive output torque from the pneumatic motor. This solution significantly improves the safety and reliability of the roller gap adjustment mechanism during normal adjustment without adding complex hardware structures, avoiding the risk of misoperation caused by repeated manual trial adjustments.

[0025] Building upon this foundation, the proposed optimization scheme introduces a mechanism for predicting the movement trend of the telescopic rod and assessing its stroke risk. This upgrades stroke protection from passively stopping after reaching the limit to actively intervening before approaching the limit. By comprehensively considering the response delay of the pneumatic system, the inertial characteristics of the transmission mechanism, and the current speed and acceleration of the telescopic rod, this invention can predict the inertial displacement that the telescopic rod may experience in a short period of time. Based on this, it adaptively suppresses the driving capability before reaching the stroke limit, allowing the telescopic rod to gradually decelerate and smoothly approach the limit position. This effectively avoids overrunning and structural impact problems caused by inertial impact and control lag.

[0026] Meanwhile, the optimized and improved scheme, by constructing a continuously varying stroke risk function, achieves refined control over the process of the telescopic rod approaching its limit. This transforms the adjustment process from a simple run-stop pattern into a flexible control process with buffering and transition characteristics. This control method not only significantly reduces the mechanical shock, vibration, and noise generated during the adjustment of the die roller gap, but also mitigates the fatigue and wear of key components such as threaded pairs, gear pairs, and limit structures, further extending the service life of the adjustment mechanism and improving the long-term stability of the equipment.

[0027] In summary, while maintaining a simple system structure and ease of engineering implementation, this invention achieves a progressive upgrade from basic stroke protection to predictive safety control. It solves the problems of lagging over-stroke protection and excessive control rigidity in existing technologies, while also taking into account adjustment efficiency and operational stability. It can adapt to the actual application needs of different working conditions and equipment specifications, and significantly improves adjustment accuracy, reliability and maintenance friendliness while improving the safety of mold roller gap adjustment. Attached Figure Description

[0028] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0029] Figure 1 This is a schematic diagram of the center distance of a telescopic rod provided in an embodiment of the present invention; Figure 2 This is a schematic flowchart of a telescopic pole motion monitoring and control method according to an embodiment of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative effort are all within the scope of protection of the present invention.

[0031] Example 1 This embodiment provides a method for monitoring and controlling the movement of the telescopic rod in a roller gap adjustment mechanism. By calculating the travel margin of the telescopic rod in both the extension and retraction directions, and converting this travel margin into the remaining rotation number of the pneumatic motor, the method prevents the pneumatic motor from continuing to move in that direction through software control, thus achieving a protection function. In terms of hardware structure, only a pulse sensor needs to be configured for the pneumatic motor to acquire the rotation number of the pneumatic motor drive shaft in real time. A pulse signal is acquired for each rotation of the pneumatic motor drive shaft, thereby achieving real-time updates of the remaining rotation number of the pneumatic motor. The air source power of the pneumatic motor is controlled by a solenoid valve. By controlling the energization state of the solenoid valve, the start, stop, and forward / reverse rotation of the pneumatic motor are achieved.

[0032] In practical applications, the main control flow is as follows: First, set the limit position of the telescopic rod travel of the mold roller gap adjustment mechanism, and obtain the center distance parameter of the telescopic rod corresponding to the limit position of the travel. Record the center distance corresponding to the longest limit position of the telescopic rod as... e The center distance corresponding to the shortest limit position isf Simultaneously, the transmission ratio parameters of the adjustment mechanism are pre-stored. k This refers to the change in length of the telescopic rod corresponding to one revolution of the pneumatic motor drive shaft. (Parameter) e , f , k All parameters are obtained by measuring or calculating the actual dimensions of the structure and are used as fixed parameters during operation.

[0033] After the user replaces the pressure roller or adjusts the position of the adjusting wheel, the initial state of the adjusting mechanism changes, requiring the safety boundary to be re-established. For example... Figure 1 As shown, the initial center distance of the telescopic rod of the adjusting mechanism was measured, and the measured value was obtained. d Then the length allowance of the telescopic rod in the extension direction can be calculated. ed and the length margin in the shortening direction df Then, based on the length allowance, calculate the remaining rotations of the pneumatic motor in both directions; that is, the remaining rotations in the extension direction are ( ed ) / k The remaining number of revolutions in the shortening direction is ( df ) / k The result is rounded down to the nearest integer.

[0034] As the pneumatic motor rotates, the remaining revolutions are updated in real time based on the number of pulses acquired by the pulse sensor. If a pulse is acquired in the extension direction, the remaining revolutions in the extension direction are decremented by 1, and the remaining revolutions in the shortening direction are simultaneously incremented by 1; conversely, if a pulse is acquired in the shortening direction, the remaining revolutions in the shortening direction are decremented by 1, and the remaining revolutions in the extension direction are simultaneously incremented by 1. Whether it extends or shortens depends on the rotation direction of the pneumatic motor. For example, forward rotation of the pneumatic motor drives the telescopic rod to extend, while reverse rotation drives it to retract.

[0035] When the remaining revolutions in the extension or retraction direction decrease to 0, the drive in that direction is cut off by shutting off the solenoid valve, preventing the pneumatic motor from continuing to rotate in that direction and thus avoiding overtravel of the telescopic rod. Simultaneously, an alarm message is issued to remind the user that the safety limit has been reached or that action is required.

[0036] The advantage of the above solution lies in its simplicity, requiring no additional displacement sensors and directly utilizing pulse counting for stroke protection. However, several significant engineering challenges remain in practical pneumatic systems. First, this solution is a typical hard threshold control that stops only when the remaining number of revolutions is zero. Its protection action occurs at the boundary point. Pneumatic motors and transmission chains have significant inertia, and there is a response time between the solenoid valve receiving the power-off command and the decrease in air pressure and motor torque. Therefore, at the instant the remaining revolutions are reduced to zero, the telescopic rod may continue to move due to inertia, easily causing minor overshooting or stalling impacts after reaching the limit, especially during high-speed adjustments, load fluctuations, or when the air source pressure is high. Second, the above solution lacks flexible control for the approaching limit process. The system operates with a constant driving force for most of the time, only suddenly stopping on the last revolution, which easily generates mechanical shock and noise. Long-term operation will accelerate the wear of threaded pairs, gear pairs, and limit structures. Furthermore, the above scheme only judges based on how much is left at the current position, which cannot reflect whether the current movement trend will exceed the control delay, nor can it distinguish between the two completely different risk situations of slow approach and high-speed approach. Therefore, in some boundary conditions, the protection strategy is too conservative or too lagging, affecting safety and stability.

[0037] Therefore, this embodiment proposes an optimized and improved scheme based on the above scheme. While keeping the original pulse counting and stroke conversion framework unchanged, it introduces the control concept of motion trend prediction and adaptive suppression of driving capability, so that the telescopic rod can enter the deceleration controlled state in advance before reaching the limit, and then perform hard cut-off when the limit is actually triggered, thereby forming a double protection mechanism of soft constraint and hard protection.

[0038] Specifically, such as Figure 2 As shown, the optimization and improvement scheme mainly includes the following steps: 1. Parameter initialization and predictive control parameter setting While retaining the structural parameters of the original scheme e , f , k Based on this, the following control parameters are further set: The sampling period Δt is used to specify the frequency of pulse acquisition and control update. Prediction Time Window , a comprehensive time scale used to characterize the response delay and aerodynamic inertia effects of solenoid valves; Safe buffer distance d safe This is used to define the width of the buffer zone that allows for early entry into flexible control when approaching the limit; Risk sensitivity coefficient This is used to adjust the rate at which risk increases with distance; Normal duty cycleD 0 is used to characterize the airflow intensity level of the solenoid valve during normal adjustment.

[0039] Recommended values ​​for all of the above parameters can be provided during the commissioning phase, and configuration can be performed on the software interface according to the model or operating condition.

[0040] 2. Initial calibration and establishment of equivalent displacement reference for the telescopic rod. Consistent with the original solution, the user measures the initial center distance of the telescopic rod after the mechanism's state changes. d Based on this, calculate the remaining travel and remaining revolutions in both directions. Simultaneously, determine the initial center distance of the telescopic boom. d As at the initial moment t 0 equivalent displacement reference value x ( t 0), definition x ( t Let be the real-time value of the center distance of the telescopic pole. Then, the longest and shortest limit positions of the telescopic pole correspond to... x max = f and x min = e .

[0041] 3. Pulse acquisition and continuous displacement update The pneumatic motor pulses are collected according to the sampling period Δt, and the number of revolutions within the current period is obtained by combining the motor rotation direction information. The equivalent displacement of the telescopic rod is updated using the following formula:

[0042] in, The value is positive in the elongation direction and negative in the shortening direction. This step still relies solely on pulse counting in hardware, without adding a displacement sensor.

[0043] 4. Online estimation of velocity and acceleration The velocity and acceleration of the telescopic rod are calculated based on the continuous displacement update results to characterize the motion trend. The velocity can be obtained based on differential calculation.

[0044] Acceleration can be further obtained based on velocity difference:

[0045] By using speed and acceleration information, it is possible to identify whether the telescopic pole is approaching its limit position at a low speed or at a high speed, providing the necessary dynamic input for prediction and risk control.

[0046] 5. Trend-based short-term location prediction Within each sampling period, based on the current displacement, velocity, and acceleration, within the prediction time window... Internal calculation of the possible future location of the front end of the telescopic pole:

[0047] Among them, the prediction time window This time delay, defined based on the actual response characteristics of the pneumatic drive system, characterizes the comprehensive time delay between the issuance of a control command and the significant attenuation of the pneumatic motor's output torque. This time delay is primarily determined by factors such as the solenoid valve response time, the air pressure decay time, the pneumatic motor's rotational inertia, and the mechanical inertia of the transmission mechanism.

[0048] in, This refers to the solenoid valve's electrical control response time, which is the time it takes for the control signal to switch to the valve core to complete its action. This is the air pressure decay time, which is the time required for the input air pressure and working pressure of the pneumatic motor to drop to a level where the effective torque is significantly reduced after the solenoid valve is closed. This refers to the equivalent mechanical inertia delay time of the pneumatic motor and telescopic rod transmission mechanism. All three time parameters can be obtained through equipment sample data, experimental measurements, or empirical calibration. In actual industrial pneumatic systems, these time parameters typically fall within the following ranges: Approximately 10~50ms Approximately 50~200ms It is approximately 50~300ms. Therefore, the prediction time window can be... The value range is set to 0.1~0.6s.

[0049] In some embodiments, the prediction time window is not included. Instead of being fixed as a constant, it is adaptively set according to the current operating state of the telescopic boom, for example:

[0050] in, Based on the response time (e.g., 0.1s). This is the speed weighting coefficient. This method automatically increases the prediction time window during high-speed adjustment, thereby enhancing safety; and decreases the prediction time window accordingly during low-speed fine-tuning, to improve control sensitivity and adjustment efficiency.

[0051] 6. Calculate the safe distance and output the current risk. Determine the extreme position based on the current driving direction. When the telescopic rod is moving in the extension direction, take When moving in the shortening direction, take Calculate the distance from the predicted position to the extreme position. .

[0052] Predicted distance and safe buffer distance d safe The input is fed into the trip risk function to calculate the trip risk value. R The travel risk function adopts a continuously differentiable sigmoid function form, that is:

[0053] in, This is a risk sensitivity coefficient, used to adjust the rate at which risk increases with distance. When... When the value is small, the risk function changes gradually, and the system gradually enters a suppressed state as it approaches the travel limit; the control process is gentle but the response is relatively conservative. When the value is large, the risk function rises rapidly near the safety buffer boundary, making the system more sensitive to travel risks and beneficial for strengthening protection in advance under high-speed or high-inertia conditions. In the mold roller gap adjustment mechanism, the telescopic rod safety buffer distance... d safe Typically within the range of 2~10mm, the corresponding risk sensitivity coefficient The recommended value range is 0.3 to 4.0.

[0054] when Much larger d safe hour, R A value close to 0 indicates a safe zone; when Close to or less than d safe hour, R A rapid increase indicates the entry into a soft-constraint deceleration zone or a high-risk zone. Compared to the hard threshold of the original scheme that only acts when the remaining risk is zero, this risk function can continuously reflect the risk level before approaching the boundary, thus providing a quantitative basis for flexible control.

[0055] 7. Risk-based adaptive control of solenoid valve drive capability The solenoid valve's drive duty cycle is adaptively adjusted based on the risk value R, so that the driving force gradually decreases as the risk increases:

[0056] This indicates the current cycle solenoid valve airflow duty cycle. This is the normal duty cycle. In practice, the solenoid valve can be pulsed on / off controlled according to the duty cycle within a sampling period. This allows the solenoid valve to reduce airflow and drive when approaching its limit, thereby automatically decelerating the telescopic rod and significantly reducing inertial impact and the probability of exceeding the limit.

[0057] 8. Limit determination and hard protection execution When the predicted position is determined to have reached or exceeded the limit boundary, i.e., the following conditions are met:

[0058] The system immediately enters hard protection mode, forcibly cutting off the air supply to the corresponding solenoid valve, locking the control command for that direction, and triggering an alarm. This hard protection, combined with the soft constraint of the adaptive control of the solenoid valve's drive capability, creates a two-level protection system: normally, it uses flexible suppression to reduce impact, and then forcibly stops the system when a real risk of exceeding the limit occurs, ensuring both safety and the lifespan of the mechanism.

[0059] After an alarm is triggered, the user can resume operation by re-executing the calibration procedure after completing the inspection or handling. The system can then display the data at the time the alarm occurred. , Key data such as R are recorded and displayed to help locate problems such as abnormal air source pressure, abnormal load, or structural jamming, thereby improving maintenance efficiency.

[0060] Example 2 Based on the above method, this embodiment provides a telescopic rod motion monitoring and control system. This system is applied in a granulation equipment that uses a pneumatic motor to drive the telescopic rod for adjusting the gap between the die rollers. It is used to monitor the motion state of the telescopic rod and control its stroke range. The monitoring and control system consists of a signal acquisition unit, a parameter calculation unit, a stroke monitoring and control unit, a drive execution unit, and a human-machine interface unit. The units interact and work collaboratively through a control bus or signal lines.

[0061] The signal acquisition unit is located at the output end of the pneumatic motor and is used to acquire its rotational status information in real time during operation. This unit includes a pulse acquisition structure synchronized with the pneumatic motor's rotation. When the pneumatic motor completes a predetermined angle or a full revolution, it generates a corresponding pulse signal and sends this signal to the control system, providing basic data for subsequent stroke monitoring. This method eliminates the need for additional displacement sensors on the telescopic rod body, reducing system hardware complexity.

[0062] The parameter calculation unit stores and retrieves the structural parameters of the roller gap adjustment mechanism, and performs basic calculations during system initialization or when the structural state changes. This unit pre-stores the travel limit parameters of the telescopic rod in the extension and retraction directions, as well as the transmission ratio parameters between the pneumatic motor and the telescopic rod. After the user completes roller replacement or gap adjustment, they input the current geometric position parameters of the telescopic rod through the human-machine interface unit. Based on the input data and structural parameters, the parameter calculation unit calculates the remaining travel margin of the telescopic rod in both motion directions, and further converts this remaining travel margin into the remaining number of rotations of the pneumatic motor in the corresponding direction, serving as a reference for travel monitoring.

[0063] The stroke monitoring and control unit is used to update and determine the remaining number of rotations in real time during the operation of the pneumatic motor. This unit receives rotation pulse signals from the signal acquisition unit and, in conjunction with the rotation direction of the pneumatic motor, dynamically adds or subtracts the remaining number of rotations corresponding to the extension and retraction directions, thereby continuously reflecting the current state of the telescopic rod's distance from its stroke limit. When the remaining number of rotations of the pneumatic motor in a certain direction is detected to decrease to a preset lower limit, the stroke monitoring and control unit outputs a control command to the drive execution unit.

[0064] The drive actuator is connected to the air supply control circuit of the pneumatic motor, preferably employing a three-position five-way solenoid valve structure to control the start, stop, and forward / reverse rotation of the pneumatic motor. Upon receiving a restriction command from the stroke monitoring and control unit, the drive actuator cuts off the air supply path to the solenoid valve in the corresponding direction, preventing the pneumatic motor from continuing to output driving force in that direction, thereby limiting the telescopic rod's continued movement in that direction and providing basic protection for the telescopic rod's stroke. Simultaneously, the human-machine interface unit displays the current stroke status and outputs an alarm prompt when protection is triggered, reminding the user to take appropriate action.

[0065] In some embodiments, to further improve the control accuracy and operational stability of the system when approaching the travel limit, the above system has been optimized and improved. Without changing the original system hardware architecture, motion trend analysis and predictive control functions are introduced through the expansion of software and control logic, so that the system is upgraded from basic travel protection to predictive safety control system.

[0066] In this optimized and improved embodiment, the stroke monitoring and control unit further integrates a motion state analysis module and a position prediction module. The motion state analysis module, while receiving pulse acquisition signals and updating the remaining rotation count, calculates the motion speed and its trend of the telescopic rod based on the changes in the equivalent displacement of the telescopic rod within adjacent sampling periods, thus characterizing the current motion state of the telescopic rod. The position prediction module, based on the current equivalent displacement state and motion trend parameters, predicts the future displacement of the telescopic rod within a preset prediction time window, thereby providing an advance assessment of possible inertial displacements of the telescopic rod before the control system response delay and aerodynamic inertia are completely eliminated.

[0067] Building upon this, the travel monitoring and control unit also includes a travel risk assessment module. This module generates travel risk parameters characterizing the extent to which the telescopic boom approaches its travel limit, based on the distance between the predicted displacement and the travel limit position corresponding to the current direction of movement. These travel risk parameters reflect the transition state of the telescopic boom from the safe zone to the high-risk zone in a continuously changing manner, enabling the control system to no longer rely solely on whether the limit has been reached, but rather to classify and identify the process of approaching the limit.

[0068] In this optimized and improved scheme, the drive actuator retains the original start / stop and direction control functions, and also adjusts the solenoid valve's drive mode based on the risk parameters output by the stroke risk assessment module. When the stroke risk is low, the drive actuator maintains normal drive mode; as the stroke risk gradually increases, the drive actuator gradually weakens the pneumatic motor's driving force by modulating the equivalent airflow intensity of the solenoid valve, causing the telescopic rod to automatically decelerate and enter a controlled state before approaching its stroke limit. When the position prediction module determines that the telescopic rod has a risk of exceeding the limit or predicts that the displacement has reached the stroke limit, the drive actuator still performs the forced air supply cut-off protection action according to the original scheme, forming a dual-layer safety mechanism combining flexible control and hard protection.

[0069] Through the above optimizations and improvements, the telescopic pole motion monitoring and control system, while maintaining the original system's simple structure and ease of engineering implementation, has achieved precise control over the telescopic pole's motion process. This not only effectively avoids the risk of overtravel operation but also significantly reduces mechanical shock and vibration during the adjustment process, improves the stability and reliability of the mold roller gap adjustment, and further expands the system's applicability and safety margin under complex working conditions.

[0070] The above system can execute the telescopic pole motion monitoring and control method described in Embodiment 1, and has the corresponding functional modules and beneficial effects of the method. For technical details not described in detail in this embodiment, please refer to the telescopic pole motion monitoring and control method provided in Embodiment 1 of this invention.

[0071] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented using software plus a general-purpose hardware platform, or of course, using hardware. Based on this understanding, the above technical solutions, in essence or the parts that contribute to the related technology, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for monitoring and controlling the movement of a telescopic rod in a mold roller gap adjustment mechanism, characterized in that, include: Obtain the initial position parameters of the telescopic rod in the mold roller gap adjustment mechanism; Set or determine the travel limit positions of the telescopic rod in the extension and retraction directions; Based on the initial position parameters and the travel limit position, calculate the travel margin of the telescopic rod in its direction of movement; Based on the transmission ratio between the telescopic rod and the pneumatic motor, the stroke margin is converted into the remaining number of rotations of the pneumatic motor in the corresponding rotation direction; The number of rotations of the pneumatic motor is collected in real time during the movement of the telescopic rod, and the remaining number of rotations corresponding to the direction of movement of the telescopic rod is dynamically updated based on the number of rotations and the direction of rotation. When the remaining number of rotations of the pneumatic motor in a certain direction decreases to zero, the air supply is immediately cut off to prevent the pneumatic motor from continuing to rotate in that direction, thereby limiting the telescopic rod from continuing to move in that direction to avoid overtravel.

2. The telescopic pole motion monitoring and control method as described in claim 1, characterized in that, The pneumatic motor is equipped with a corresponding pulse sensor. The pneumatic motor drive shaft acquires a pulse signal for each rotation, thereby realizing the real-time acquisition of the number of rotations of the pneumatic motor drive shaft and the real-time update of the remaining number of rotations.

3. The telescopic pole motion monitoring and control method as described in claim 1, characterized in that, It also includes a telescopic pole motion trend prediction and adaptive suppression mechanism: S1. During the movement of the telescopic rod, the equivalent displacement of the telescopic rod is determined in real time according to the number of rotations of the pneumatic motor, and the motion trend parameters of the telescopic rod are obtained based on the equivalent displacement and its relationship with time. S2. Based on the motion trend parameters, predict the future displacement of the telescopic rod within a preset prediction time window, and generate a travel risk parameter characterizing the telescopic rod approaching the travel limit position based on the distance between the predicted displacement and the travel limit position corresponding to the current motion direction. S3. Based on the aforementioned stroke risk parameters, the driving force of the pneumatic motor is adaptively adjusted so that the telescopic rod gradually reduces its movement speed before approaching the stroke limit position. S4. When the predicted displacement reaches or exceeds the travel limit position in the corresponding direction, the air supply to the pneumatic motor in that direction is cut off to prevent the telescopic rod from continuing to move in that direction.

4. The telescopic pole motion monitoring and control method as described in claim 3, characterized in that, In step S1, the equivalent displacement is expressed as: in, and These represent the time intervals of the telescopic pole. and The equivalent displacement. The sampling period is for the number of rotations of the pneumatic motor; This represents the increment of the number of rotations within the sampling period, and The value is positive when the telescopic pole extends and negative when it retracts. k The transmission ratio between the telescopic rod and the pneumatic motor represents the change in the length of the telescopic rod corresponding to one revolution of the pneumatic motor drive shaft. The motion trend parameters include the speed and acceleration of the telescopic pole: ， in, and These represent the time intervals of the telescopic pole. and The speed of movement, For the telescopic pole at any time The acceleration.

5. The telescopic pole motion monitoring and control method as described in claim 4, characterized in that, In step S2, the predicted displacement is expressed as: in, Indicates time The predicted displacement; To predict the width of the time window, we have: in, This refers to the electrical control response time of the solenoid valve. This refers to the gas path pressure decay time. This is the equivalent mechanical inertia delay time for pneumatic motors and telescopic rod transmission mechanisms.

6. The telescopic pole motion monitoring and control method as described in claim 5, characterized in that, The width of the prediction time window is adaptively set according to the operating status of the telescopic boom: in, for The width of the prediction time window at time. Based on response time, The speed weighting coefficient is used; in high-speed adjustment mode, the prediction time window automatically increases, thereby enhancing safety; in low-speed fine-tuning mode, the prediction time window decreases accordingly to improve control sensitivity and adjustment efficiency.

7. The telescopic pole motion monitoring and control method as described in claim 5, characterized in that, In step S2, the trip risk parameter is expressed as: in, R This represents the trip's risk value. This is the risk sensitivity coefficient, used to adjust the rate at which risk increases with distance; d safe A pre-set safety buffer distance; Indicates the travel limit position corresponding to the predicted displacement and the current direction of motion. The distance between them.

8. The telescopic pole motion monitoring and control method as described in claim 7, characterized in that, In step S3, based on the trip risk value R The solenoid valve's drive duty cycle is adaptively adjusted so that the driving force gradually decreases as the risk increases: in, Indicates time t The solenoid valve's airflow duty cycle within the specified period. The normal duty cycle is used to control the solenoid valve in a pulse manner according to the duty cycle within one cycle. This reduces the air supply and drive when the telescopic rod is close to its stroke limit, thereby allowing the telescopic rod to decelerate automatically and reducing the probability of inertial impact and exceeding the limit.

9. A telescopic rod motion monitoring and control system for a die roller gap adjustment mechanism based on the method of any one of claims 1 to 8, characterized in that, Includes the following modules: The signal acquisition unit is used to acquire the rotation status information of the pneumatic motor in real time during operation and generate a rotation pulse signal corresponding to the number of rotations of the pneumatic motor. The parameter calculation unit is used to calculate the travel margin of the telescopic rod in the extension direction and the shortening direction according to the input initial position parameters of the telescopic rod, and convert the travel margin into the remaining number of rotations of the pneumatic motor in the corresponding direction based on the transmission ratio relationship between the pneumatic motor and the telescopic rod. The stroke monitoring and control unit is communicatively connected to the signal acquisition unit and the parameter calculation unit. During the operation of the pneumatic motor, it updates the remaining number of rotations corresponding to the extension direction and the shortening direction in real time according to the rotation pulse signal and the rotation direction of the pneumatic motor, and determines whether the remaining number of rotations has reached the preset lower limit condition. The drive execution unit is connected to the stroke monitoring and control unit and to the air source control circuit of the pneumatic motor. When the stroke monitoring and control unit determines that the remaining number of rotations of the pneumatic motor in a certain direction has reached a preset lower limit, it controls the solenoid valve corresponding to the direction of the pneumatic motor to stop supplying air, so as to prevent the pneumatic motor from continuing to rotate in that direction, thereby limiting the telescopic rod from continuing to move in that direction. The human-machine interaction unit is used to output an alarm prompt when the remaining number of rotations reaches a preset lower limit condition, and is also used to receive the initial position parameters and control commands of the telescopic rod input by the user.

10. The telescopic pole motion monitoring and control system as described in claim 9, characterized in that, The trip monitoring and control unit also includes a motion state analysis module, a location prediction module, and a trip risk assessment module; The motion state analysis module is used to determine the current equivalent displacement state of the telescopic rod based on the rotation pulse signal, and to obtain the motion trend parameters of the equivalent displacement state over time. The position prediction module is used to predict the future displacement of the telescopic pole within a preset prediction time window based on the equivalent displacement state and the motion trend parameters. The travel risk assessment module is used to generate travel risk parameters that characterize the telescopic rod approaching its travel limit position based on the distance between the predicted displacement and the travel limit position corresponding to the current direction of movement. The drive actuator is also used to adaptively adjust the driving force of the pneumatic motor according to the stroke risk parameter, so that the telescopic rod gradually reduces its movement speed before approaching the stroke limit position, and cuts off the air supply of the pneumatic motor in the corresponding direction when the predicted displacement reaches or exceeds the stroke limit position.

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