Method for detecting travel distance of crane in real time by using coded disc

Abstract

The invention provides a method for detecting the travel distance of a crane in real time by using a coded disc, which comprises the following steps of: carrying out pulse counting by using the coded disc, increasing the pulse number of the coded disc by one gear when the crane moves forwards by one station, and reducing the pulse number of the coded disc by one gear when the crane moves backwards by one station; the PLC controls the speed adjusting device to adjust the speed of the crane, the crane runs to a target position, a processing result is sent to the display module to be displayed, and speed increasing, intelligent speed adjusting, service life prolonging, high efficiency, stability and capacity increasing are achieved.

Description

Technical Field

[0001] The present application relates to the field of crane control technology, and in particular to a method for detecting the travel distance of a crane in real time by using a code disk. Background Art

[0002] At present, the operation of cranes is mostly based on manual judgment of the starting position and target position of the crane, and operation is based on experience, which not only has low positioning accuracy, but also low work efficiency. Therefore, the industry also uses binary address reading to control the operation of the crane, such as controlling acceleration, speed, etc. However, due to the step-by-step control of the binary address reading method, the crane has a long deceleration distance and a long deceleration time, and the crane is seriously frustrated, which affects the life of the crane. To this end, the prior art solves the above problems by using a host computer to control the crane.

[0003] For example, Chinese patent document CN110228754A discloses an industrial crane control method with adaptive speed planning. The kinematic model and anti-sway control model of the crane system are established based on the Lagrange equation. The adaptive speed planning uses multi-stage acceleration and deceleration to achieve a stable anti-sway effect. The speed stage number and the maximum speed are adaptively controlled. The maximum operating speed of the crane is set to k levels, with the kth level being the highest speed and the first level being the lowest speed. The adaptive speed planning is specifically divided into the following steps: Step 1: Calculate the target distance (Δx = |x 2 -x 1 |) from the current position x 1 and the target position x 2 , set the maximum speed vn of the crane equal to the kth speed of the crane, and calculate the number of acceleration and deceleration stages n according to the formula, where a is the set acceleration of the crane, and T is the single pendulum period of the crane; Step 2: Determine whether the current acceleration / deceleration stage number n is greater than or equal to 2. If n is greater than or equal to 2, proceed to step 3. If n is less than 2, reduce the final speed vn of the crane by one gear, go to step 1, and recalculate n. Step 3: In the starting acceleration phase, the speed curve and acceleration displacement of the acceleration phase are planned. From the initial speed v 0 = 0 m / s, the system-set acceleration a is used to accelerate to the speed v 1 , and the current speed v 1 is maintained at a constant speed for a period of ts. Then, the speed v 1 is accelerated to the speed v 2 with the acceleration a, and the current speed v 2 is maintained at a constant speed for a period of ts. According to this rule, the target speed vn is reached by accelerating n times. The speeds after each acceleration are v 1 , v 2 ……vn , respectively. The speed curve and displacement of the acceleration phase are obtained. Step 4: Stop the deceleration stage, plan the speed curve and deceleration displacement of the deceleration stage, decelerate from the initial speed vn of the deceleration stage to the speed vn-1 with acceleration -a, maintain uniform motion at the current speed vn-1 for a period of ts, then decelerate from the speed vn-1 to the speed vn-2 with acceleration -a, maintain uniform motion at the current speed vn-2 for a period of ts. According to this rule, the speed is 0m / s after deceleration n times, and the speed after each deceleration is vn-1...v2, v1, 0, respectively, to obtain the speed curve and displacement of the deceleration stage; Step 5: Calculate the time tr used in the uniform speed stage from the target distance, acceleration stage displacement, deceleration stage displacement and speed vn. If tr is greater than zero, obtain the uniform speed stage speed curve and displacement and go to step 6. If tr is less than zero, reduce the number of acceleration and deceleration stages n by 1 and go to step 2. Step 6: Output the adaptive speed planning curve of the crane.

[0004] Through such model software calculations, the safety, reliability and work efficiency of crane transportation in industrial production have been greatly improved. However, through such software control, the operating cost and electricity cost have been significantly increased. Once the software fails, the safety and reliability cannot be guaranteed. On the other hand, the swing of the crane during operation is a normal phenomenon. The swing problem is solved by controlling the swing angle, which further increases the cost.

[0005] However, there is an urgent need for a technical solution that can create efficient and stable system operation by using a code disc to detect travel distance and optimize equipment. Summary of the invention

[0006] In view of the technical problems existing in the prior art, the present invention aims to provide a solution for real-time detection of crane travel distance and equipment optimization using a code disk, so as to achieve speed improvement, intelligent speed regulation, life extension, high efficiency and stability, and increased production capacity.

[0007] Specifically, according to one aspect of the present invention, a method for real-time detection of crane travel distance using a code disc is provided, the method comprising: A code disc is installed on the main transmission shaft of the crane's transverse mechanism, a PS (or POS) is installed at a position opposite to the code slot of the code disc, and a PLC is electrically connected to the PS (or POS). The PS or POS incident light signal passes through the code slot of the code disc to generate a transverse pulse signal. The PLC receives the transverse pulse signal to generate a transverse pulse parameter, and uses the code disc to count pulses. When the crane moves forward by one station, the number of code disc pulses increases by one level, and when the crane moves backward by one station, the number of code disc pulses decreases by one level. A monitoring device, a detection device, and a speed regulating device are electrically connected to the PLC, wherein the monitoring device includes a data processing module, a signal receiving module, and a display module; the detection device includes a positioning module, an image acquisition module, a signal sending module, an angle measuring module, and a distance measuring module; the positioning module is used to determine the target position of the crane; the image acquisition module is used to collect image data of the real-time operation of the crane; the angle measuring module is used to detect the swing angle of the crane in real time; the distance measuring module is used to detect the travel distance between the crane and the target position in real time; the signal sending module is used to send the collected image data, distance data, and the target position of the crane to the signal receiving module; the data processing module processes the data received by the signal receiving module, and inputs the processing result to the PLC; the PLC controls the speed regulating device to adjust the speed of the crane according to the processing result, runs the crane to the target position, and sends the processing result to the display module for display.

[0008] According to the method of using a code disc to detect the travel distance of a crane in real time, when the crane moves forward, the number of code disc pulses increases, and when the crane moves backward, the number of code disc pulses decreases. The real-time angle and real-time position of the crane are calculated based on the lateral movement pulse parameters and the number of pulses to calculate the travel distance between the crane and the target position.

[0009] According to the method of using a code disk to detect the travel distance of a crane in real time of the present invention, when the transverse movement pulse parameter matches the preset parking trigger condition, the PLC sends a deceleration signal to the drive motor of the transverse movement mechanism of the crane.

[0010] According to the method of using the encoder to detect the crane travel distance in real time, the moving speed V of the traverse mechanism and the crane swing angle (i.e., the angle between the suspended object and the vertical direction) are obtained, and the mass m of the suspended object is obtained. According to the travel distance and the crane swing angle, according to Newton's law and motion formula, the acceleration a during acceleration and deceleration is calculated, and the balance acceleration -a is output in reverse. Based on the travel distance data, the crane acceleration and deceleration curve is intelligently optimized so that the traverse mechanism reaches balance in the acceleration or deceleration stage and stops accurately during deceleration. The impact on the gear rack is effectively reduced, and its service life is significantly extended.

[0011] According to the method for detecting the travel distance of a crane in real time by using a code disc of the present invention, the travel distance includes a horizontal distance and a vertical distance.

[0012] According to the method for detecting the travel distance of a crane in real time by using a code disk of the present invention, when optimizing the acceleration and deceleration curve of the crane, the swing angle range is controlled to be 0-20°.

[0013] According to the method for detecting the travel distance of a crane in real time by using a code disk of the present invention, when optimizing the acceleration and deceleration curve of the crane, the swing angle range is controlled to be 0-5°.

[0014] According to the method for real-time detection of crane travel distance using a code disk of the present invention, the communication between the signal receiving module and the signal sending module adopts a short-distance transmission mode.

[0015] According to the method for real-time detection of crane travel distance using a code disk of the present invention, the communication between the signal receiving module and the signal sending module adopts RFID.

[0016] According to the method for real-time detection of crane travel distance using a code disk of the present invention, the communication between the signal receiving module and the signal sending module adopts Zigbee mode.

[0017] The method for real-time detection of crane travel distance using a code disk according to the present invention has at least the following beneficial effects: 1. Speed ​​improvement: Break through tradition and realize linear lateral movement: abandon the traditional multi-speed control mode (such as CN110228754A in the background technology), use the encoder to detect the crane travel distance in real time, and realize the linear lateral movement of the crane from the starting position to the target position.

[0018] Say goodbye to low speed and improve efficiency: For special large tank targets such as tin tanks and copper tanks, it solves the inefficiency problem caused by low-speed lateral movement in the traditional mode, shortens the lateral movement time, and improves the overall operating efficiency of the equipment.

[0019] 2. Intelligent speed regulation to extend service life: Smooth transition and minimized impact: Based on the travel distance data, the crane acceleration and deceleration curves are intelligently optimized to effectively reduce the impact on the gear rack and significantly extend its service life.

[0020] Reduce costs and increase efficiency, worry-free maintenance: Reduce gear rack wear, reduce maintenance costs and the frequency of consumables replacement, and achieve long-term and stable operation of the equipment.

[0021] 3. High efficiency and stability, improved production capacity: In the crane travel bureau based on pulse number tracking, because the pulse-per-second number is a continuous value, and because the linear deceleration method is used to replace the existing binary-based step deceleration, on the one hand, the crane travels more smoothly, which can reduce setbacks and damage to parts. On the other hand, the deceleration time is shorter, which can reduce the production cycle and improve production capacity.

[0022] Speed ​​and stability: Under the premise of ensuring the smooth and reliable operation of the crane, the lateral movement speed is increased, the operation cycle is shortened, and the equipment production capacity is improved.

[0023] Low cost, high output: Achieve higher output with lower operating costs, enhance corporate competitiveness, and help maximize corporate benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram showing a crane transverse movement mechanism according to a specific embodiment of the present invention using three cranes to mount a target object to generate a swing angle during transverse movement.

[0025] Figure 2 The figure is a schematic diagram of a system for detecting the travel distance of a crane in real time by using a code disk according to a specific embodiment of the present invention.

[0026] Figure 3 The present invention is a block diagram showing a process of using a code disk to detect the travel distance of a crane in real time according to a specific embodiment of the present invention.

[0027] Figure numerals: 1-code disc; 2-PS (POS); 3-PLC; 4-monitoring device; 41-data processing module; 42-signal receiving module; 43-display module; 5-detection device; 51-positioning module; 52-image acquisition module; 53-signal sending module; 54-angle measuring module; 55-distance measuring module; 6-speed adjustment device; 7-code gap. DETAILED DESCRIPTION

[0028] The present invention will be described in detail below in combination with specific embodiments with reference to the accompanying drawings. Those skilled in the art will appreciate that the description is exemplary and the present invention is not limited to the specific embodiments.

[0029] Figure 2 The figure is a schematic diagram of a system for detecting the travel distance of a crane in real time by using a code disk according to a specific embodiment of the present invention. Figure 3 It is a block diagram of the process.

[0030] like Figure 2 As shown, a code disc 1 is installed on the main transmission shaft of the crane's transverse mechanism, a PS (or POS) 2 is installed at a position opposite to the code slot 7 of the code disc, and a PLC (programmable logic controller) 3 is electrically connected to the PS (or POS). The PS or POS incident light signal passes through the code slot 7 of the code disc to generate a transverse pulse signal. The PLC 3 receives the transverse pulse signal to generate a transverse pulse parameter, and the code disc 1 is used to count pulses. When the crane moves forward for each station, the code disc pulse number increases by one level, and when the crane moves backward for each station, the code disc pulse number decreases by one level. A monitoring device 4, a detection device 5, and a speed regulating device 6 are electrically connected to the PLC3, wherein the monitoring device 4 includes a data processing module 41, a signal receiving module 42, and a display module 43; the detection device 5 includes a positioning module 51, an image acquisition module 52, a signal sending module 53, an angle measuring module 54, and a distance measuring module 55; the positioning module 51 is used to determine the target position of the crane; the image acquisition module 52 is used to collect image data of the real-time operation of the crane; the angle measuring module 54 is used to detect the swing angle of the crane in real time; the distance measuring module 55 is used to detect the travel distance between the crane and the target position in real time; the signal sending module 53 is used to send the collected image data, distance data, and the target position of the crane to the signal receiving module 42; the data processing module 41 processes the data received by the signal receiving module 42, and inputs the processing result to the PLC3; the PLC controls the speed regulating device 6 to adjust the speed of the crane according to the processing result, runs the crane to the target position, and sends the processing result to the display module 43 for display.

[0031] In the present invention, when the crane moves forward, the pulse number of the code disk increases, and when the crane moves backward, the pulse number of the code disk decreases. According to the traverse pulse parameter and the pulse number, the real-time angle and real-time position of the crane are calculated to calculate the travel distance between the crane and the target position. Figure 1 The figure shows that the transverse movement mechanism adopts three cranes, but this is only exemplary. In practice, a single crane or a group of three cranes can be adopted. Figure 3 It is a schematic diagram showing the detection of the crane travel distance of the present invention. When the crane speed is obtained after calculating the travel distance, the speed actually corresponds to the code disk reading address frequency. The PLC runs the crane to the target position according to the speed or frequency.

[0032] When the transverse movement pulse parameter matches the preset parking trigger condition, the PLC sends a deceleration signal to the drive motor of the transverse movement mechanism of the crane.

[0033] Obtain the moving speed V of the transverse mechanism and the crane swing angle (i.e., the angle between the suspended object and the vertical direction), obtain the mass m of the suspended object, calculate the acceleration a during acceleration and deceleration according to the travel distance and the crane swing angle, Newton's law and motion formula, and output the balance acceleration -a in reverse. Based on the travel distance data, intelligently optimize the crane acceleration and deceleration curve so that the transverse mechanism reaches balance during the acceleration or deceleration stage and stops accurately during deceleration. In this way, the impact on the gear rack is effectively reduced and its service life is significantly extended.

[0034] In the present invention, the travel distance includes a horizontal distance and a vertical distance. Although the description is made based on the horizontal distance, in fact, the vertical distance can also be processed in the same way.

[0035] In the present invention, when optimizing the acceleration and deceleration curve of the crane, the swing angle range is controlled to be 0-20°. Preferably, the swing angle range is controlled to be 0-5°. The smaller the swing angle control, the better. On the other hand, the wind force factor can also be considered for correction, and it is only necessary to increase the wind force when using Newton's second law.

[0036] In the present invention, the communication between the signal receiving module and the signal sending module adopts a short-distance transmission method, such as an RFID method or a Zigbee method, which can be freely selected according to the occasion.

[0037] According to the present invention, due to the smooth transition, the impact is minimized: Based on the travel distance data, the acceleration and deceleration curve of the crane is intelligently optimized, which effectively reduces the impact on the gear rack and significantly extends its service life. Since the travel distance of the crane is tracked based on the number of pulses, because the pulse-per-second number is a continuous value, and because the linear deceleration method is used to replace the existing binary-based step deceleration, on the one hand, the crane travels more smoothly, which can reduce setbacks and damage to parts, and on the other hand, the deceleration time is shorter, which can reduce the production cycle and improve production capacity.

[0038] In summary, the present invention has been described in detail in conjunction with specific implementation methods. Those skilled in the art will understand that various modifications and changes may be made. As long as they do not depart from the purpose and spirit of the present invention, these modifications and changes should fall within the protection scope of the present invention. The protection scope of the present invention is defined by the attached claims.

Claims

1. A method for real-time detection of crane travel distance using a code disc, the method comprising: A code disc is installed on the main transmission shaft of the crane's transverse mechanism, a PS or POS is installed at a position opposite to the code gap of the code disc, and the PS or POS is electrically connected to a PLC. The PS or POS transmits a light signal through the code gap of the code disc to generate a transverse pulse signal. The PLC receives the transverse pulse signal to generate a transverse pulse parameter, and uses the code disc to count pulses. When the crane moves forward by one station, the number of code disc pulses increases by one level, and when the crane moves backward by one station, the number of code disc pulses decreases by one level. A monitoring device, a detection device, and a speed regulating device are electrically connected to the PLC, wherein the monitoring device includes a data processing module, a signal receiving module, and a display module; the detection device includes a positioning module, an image acquisition module, a signal sending module, an angle measuring module, and a distance measuring module; the positioning module is used to determine the target position of the crane; the image acquisition module is used to collect image data of the real-time operation of the crane; the angle measuring module is used to detect the swing angle of the crane in real time; the distance measuring module is used to detect the travel distance between the crane and the target position in real time; the signal sending module is used to send the collected image data, distance data, and the target position of the crane to the signal receiving module; the data processing module processes the data received by the signal receiving module, and inputs the processing result to the PLC; the PLC controls the speed regulating device to adjust the speed of the crane according to the processing result, runs the crane to the target position, and sends the processing result to the display module for display.

2. The method for real-time detection of crane travel distance using a code disc according to claim 1 is characterized in that: When the crane moves forward, the number of encoder pulses increases, and when the crane moves backward, the number of encoder pulses decreases. Based on the lateral movement pulse parameters and the number of pulses, the real-time angle and real-time position of the crane are calculated to calculate the travel distance between the crane and the target position.

3. The method for real-time detection of crane travel distance using a code disc according to claim 2, characterized in that: When the transverse movement pulse parameter matches the preset parking trigger condition, the PLC sends a deceleration signal to the drive motor of the transverse movement mechanism of the crane.

4. The method for real-time detection of crane travel distance using a code disc according to any one of claims 1 to 3, characterized in that: The moving speed of the transverse movement mechanism and the swing angle of the crane are obtained, and the mass of the hoisted object is obtained. According to the travel distance and the swing angle of the crane, the acceleration and deceleration curve of the crane is optimized so that the transverse movement mechanism can stop accurately when decelerating.

5. The method for real-time detection of crane travel distance using a code disc according to claim 4, characterized in that: The travel distance includes a horizontal distance and a vertical distance.

6. The method for real-time detection of crane travel distance using a code disc according to claim 4, characterized in that: When optimizing the acceleration and deceleration curve of the crane, the swing angle range is controlled to be 0-20°.

7. The method for real-time detection of crane travel distance using a code disk according to claim 6, characterized in that: When optimizing the crane acceleration and deceleration curve, the swing angle range is controlled to be 0-5°.

8. The method for real-time detection of crane travel distance using a code disk according to claim 4, characterized in that: The communication between the signal receiving module and the signal sending module adopts a short-distance transmission mode.

9. The method for real-time detection of crane travel distance using a code disk according to claim 4, characterized in that: The communication between the signal receiving module and the signal sending module adopts RFID mode.

10. The method for real-time detection of crane travel distance using a code disk according to claim 4, characterized in that: The communication between the signal receiving module and the signal sending module adopts Zigbee mode.

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