A crown block hoisting height measuring device and method

Abstract

The present application relates to a kind of crown hoisting height measuring device and method, belong to steelmaking equipment and method technical field.The technical scheme of the present application is: hoisting limiter (7) and height measuring gear (8) are installed on the transmission shaft (9) of hoisting drum A (3), proximity switch A (10) and proximity switch B (11) are fixed side by side on the one side of height measuring gear (8);Hoisting limiter (7), proximity switch A (10) and proximity switch B (11) are connected with operation PLC (13) respectively.The beneficial effects of the present application are: hoisting height is calculated by using height measuring gear and proximity switch, hoisting limiter signal is accessed to operation PLC, ensure that plate hook operating process will not occur landing and overheight accident, while using hoisting limit to correct measurement height value, investment cost is low, positioning accuracy meets the requirement of safe operation.

Description

Technical Field

[0001] This invention relates to a crane lifting height measuring device and method, belonging to the technical field of steelmaking equipment and methods. Background Technology

[0002] Tangshan Iron & Steel's steelmaking division has a total of 51 overhead cranes in 16 spans. Among them, 23 metallurgical casting cranes are equipped with safety monitoring systems, and the main and auxiliary hoists are equipped with encoders to calculate the hoisting height. The remaining overhead cranes are not equipped with encoders. The continuous casting span overhead crane has not displayed the hoisting height, and there have been accidents where the crane collided with the platform guardrail and dust hood. It is necessary to measure the hoisting height of the crane so that the operators can know the height of the crane hook, thereby operating the crane more accurately and avoiding the recurrence of collision accidents. Summary of the Invention

[0003] The purpose of this invention is to provide a crane lifting height measurement device and method. The lifting height is calculated by using a height measuring gear and a proximity switch. The lifting limiter signal is connected to the PLC to ensure that no accidents such as falling or exceeding the height limit occur during the operation of the crane hook. At the same time, the lifting limiter is used to correct the measured height value. The cost is low, the positioning accuracy meets the requirements of safe operation, and the invention effectively solves the above-mentioned problems existing in the background technology.

[0004] The technical solution of this invention is: a crane lifting height measuring device, comprising a lifting motor A, a lifting motor B, a lifting drum A, a lifting drum B, a transmission box, a hook plate, a lifting limit switch, a height measuring gear, a transmission shaft, proximity switches A and B, and an operational PLC. The lifting motors A and B drive the lifting drums A and B through the transmission box, and the hook plate is connected to the lifting drums A and B. The lifting limit switch and the height measuring gear are mounted on the transmission shaft of the lifting drum A, and proximity switches A and B are fixed side by side to one side of the height measuring gear. The lifting limit switch, proximity switches A and B are respectively connected to the operational PLC.

[0005] The drive shaft is coaxially connected to the lifting drum A. The height measuring gear is a circular metal plate with gears, which is fixed on the drive shaft. When the plate hook is lifted, the drive shaft drives the height measuring gear to rotate synchronously.

[0006] It also includes a proximity switch bracket. Proximity switches A and B are fixed side by side to one side of the height measuring gear via the proximity switch bracket, and the proximity switch bracket is fixed to the base of the crane drum output shaft.

[0007] The proximity switches A and B are installed side by side, one above the other, to ensure that the phase difference between the signals generated by the height measuring gear as it rotates and passes through proximity switches A and B is 90 degrees.

[0008] A method for measuring the lifting height of an overhead crane includes the following steps: (1) Lifting motor A and lifting motor B drive lifting drum A and lifting drum B to rotate through the transmission box to complete the lifting and lowering operation of the plate hook; (2) The height measuring gear is installed on the drive shaft of the lifting drum A. When the plate hook moves up and down, the height measuring gear rotates accordingly. (3) Proximity switch A and proximity switch B are fixed side by side on one side of the height measuring gear. When the teeth of the height measuring gear pass over the proximity switch, proximity switch A and proximity switch B generate pulse signals and transmit them to the PLC. (4) The PLC analyzes the number of pulse signals and calculates the number of rotations based on the initial settings to achieve real-time monitoring of the lifting and lowering height of the hook. (5) The lifting limit switch is installed on the drive shaft of the lifting drum A. The lifting limit switch signal is connected to the PLC to ensure that no accident of falling or exceeding the height occurs during the operation of the plate hook.

[0009] In step (4), the algorithm for calculating the PLC height is as follows: (41) A rising edge signal is generated when the teeth of the height measuring gear slide into the area above proximity switches A and B; a falling edge signal is generated when the teeth of the height measuring gear slide out of the area below proximity switches A and B. (42) Steps for calculating the lifting height of the hook: When the PLC detects that the signals from proximity switch A and proximity switch B are zero, the PLC records a 0 signal. When the height measuring gear rotates, and proximity switch A generates a rising edge signal before proximity switch B, the PLC records signal 11. The PLC detects whether proximity switch B generates a rising edge signal. If it is the first signal after proximity switch A generates a rising edge signal, the PLC records signal 12; otherwise, it is judged as a malfunction and the PLC restores the signal to 0. The PLC detects whether proximity switch A generates a falling edge signal. If it is the first signal after proximity switch B generates a rising edge signal, the PLC records signal 13. Otherwise, it is judged as a malfunction and the PLC restores the signal to 11. The PLC detects whether proximity switch B generates a falling edge signal. If it is the first signal after proximity switch A generates a falling edge signal, the PLC increases the equivalent by 1. Otherwise, it is judged as a malfunction and the PLC restores the signal to 12. (43) Steps for calculating the lowering height of the hook: When the PLC detects that the signals from proximity switch A and proximity switch B are zero, the PLC records a 0 signal. When the height measuring gear rotates, and proximity switch B generates a rising edge signal before proximity switch A, the PLC records signal 21. The PLC detects whether proximity switch A generates a rising edge signal. If it is the first signal after proximity switch B generates a rising edge signal, the PLC records signal 22. Otherwise, it is judged as a malfunction and the PLC restores the signal to 0. The PLC detects whether proximity switch B generates a falling edge signal. If it is the first signal after proximity switch A generates a rising edge signal, the PLC records signal 23. Otherwise, it is judged as a malfunction and the PLC restores the signal to 21. The operational PLC detects whether proximity switch A generates a falling edge signal. If it is the first signal after proximity switch B generates a falling edge signal, the operational PLC increases the equivalent by -1. Otherwise, it is judged as a malfunction, and the operational PLC restores the signal to 22.

[0010] It also includes correcting the height value measured by the PLC through the lifting limit switch signal.

[0011] The beneficial effects of this invention are: by using a height measuring gear and a proximity switch to calculate the lifting height, and by connecting the lifting limiter signal to the PLC, it ensures that no accidents such as falling or exceeding the height limit will occur during the operation of the hook. At the same time, the lifting limiter is used to correct the measured height value, resulting in low investment cost and positioning accuracy that meets the requirements for safe operation. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the height measuring gear of the present invention; Figure 3 This is a flowchart of the PLC algorithm of the present invention; Figure 4 This is the electrical signal diagram of proximity switch A of the present invention; Figure 5 This is the electrical signal diagram of proximity switch B of the present invention; Figure 6 This is a graph showing the electrical signals and height changes of proximity switches A and B according to the present invention. In the diagram: hoisting motor A1, hoisting motor B2, hoisting drum A3, hoisting drum B4, transmission box 5, plate hook 6, hoisting limit switch 7, height measuring gear 8, transmission shaft 9, proximity switch A10, proximity switch B11, proximity switch bracket 12, PLC 13, signal model 14, height change 15. Detailed Implementation

[0013] To make the purpose, technical solutions, and advantages of the invention's embodiments clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only a small part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0014] A crane lifting height measuring device includes a lifting motor A1, a lifting motor B2, a lifting drum A3, a lifting drum B4, a transmission box 5, a hook 6, a lifting limit switch 7, a height measuring gear 8, a drive shaft 9, a proximity switch A10, a proximity switch B11, and an operational PLC 13. The lifting motors A1 and B2 drive the lifting drums A3 and B4 through the transmission box 5. The hook 6 is connected to the lifting drums A3 and B4. The lifting limit switch 7 and the height measuring gear 8 are mounted on the drive shaft 9 of the lifting drum A3. The proximity switches A10 and B11 are fixed side by side to one side of the height measuring gear 8. The lifting limit switch 7, proximity switches A10 and B11 are respectively connected to the operational PLC 13.

[0015] The drive shaft 9 is coaxially connected to the lifting drum A3. The height measuring gear 8 is a circular metal plate with gears, which is fixed on the drive shaft 9. When the plate hook 6 is lifted, the drive shaft 9 drives the height measuring gear 8 to rotate synchronously.

[0016] It also includes a proximity switch bracket 12, with proximity switches A10 and B11 fixed side by side to one side of the height measuring gear 8 via the proximity switch bracket 12, and the proximity switch bracket 12 fixed to the base of the crane drum output shaft.

[0017] The proximity switches A10 and B11 are installed side by side, one above the other, to ensure that the phase difference of the signal generated when the height measuring gear 8 rotates and passes through proximity switches A10 and B11 is 90 degrees.

[0018] A method for measuring the lifting height of an overhead crane includes the following steps: (1) Lifting motor A and lifting motor B drive lifting drum A and lifting drum B to rotate through the transmission box to complete the lifting and lowering operation of the plate hook; (2) The height measuring gear is installed on the drive shaft of the lifting drum A. When the plate hook moves up and down, the height measuring gear rotates accordingly. (3) Proximity switch A and proximity switch B are fixed side by side on one side of the height measuring gear. When the teeth of the height measuring gear pass over the proximity switch, proximity switch A and proximity switch B generate pulse signals and transmit them to the PLC. (4) The PLC analyzes the number of pulse signals and calculates the number of rotations based on the initial settings to achieve real-time monitoring of the lifting and lowering height of the hook. (5) The lifting limit switch is installed on the drive shaft of the lifting drum A. The lifting limit switch signal is connected to the PLC to ensure that no accident of falling or exceeding the height occurs during the operation of the plate hook.

[0019] In step (4), the algorithm for calculating the PLC height is as follows: (41) A rising edge signal is generated when the teeth of the height measuring gear slide into the area above proximity switches A and B; a falling edge signal is generated when the teeth of the height measuring gear slide out of the area below proximity switches A and B. (42) Steps for calculating the lifting height of the hook: When the PLC detects that the signals from proximity switch A and proximity switch B are zero, the PLC records a 0 signal. When the height measuring gear rotates, and proximity switch A generates a rising edge signal before proximity switch B, the PLC records signal 11. The PLC detects whether proximity switch B generates a rising edge signal. If it is the first signal after proximity switch A generates a rising edge signal, the PLC records signal 12; otherwise, it is judged as a malfunction and the PLC restores the signal to 0. The PLC detects whether proximity switch A generates a falling edge signal. If it is the first signal after proximity switch B generates a rising edge signal, the PLC records signal 13. Otherwise, it is judged as a malfunction and the PLC restores the signal to 11. The PLC detects whether proximity switch B generates a falling edge signal. If it is the first signal after proximity switch A generates a falling edge signal, the PLC increases the equivalent by 1. Otherwise, it is judged as a malfunction and the PLC restores the signal to 12. (43) Steps for calculating the lowering height of the hook: When the PLC detects that the signals from proximity switch A and proximity switch B are zero, the PLC records a 0 signal. When the height measuring gear rotates, and proximity switch B generates a rising edge signal before proximity switch A, the PLC records signal 21. The PLC detects whether proximity switch A generates a rising edge signal. If it is the first signal after proximity switch B generates a rising edge signal, the PLC records signal 22. Otherwise, it is judged as a malfunction and the PLC restores the signal to 0. The PLC detects whether proximity switch B generates a falling edge signal. If it is the first signal after proximity switch A generates a rising edge signal, the PLC records signal 23. Otherwise, it is judged as a malfunction and the PLC restores the signal to 21. The operational PLC detects whether proximity switch A generates a falling edge signal. If it is the first signal after proximity switch B generates a falling edge signal, the operational PLC increases the equivalent by -1. Otherwise, it is judged as a malfunction, and the operational PLC restores the signal to 22.

[0020] It also includes correcting the height value measured by the PLC through the lifting limit switch signal.

[0021] In practical applications, the implementation goal is to display the lifting height of the 160-ton crane in the continuous casting section of the steelmaking division on the touch screen in the driver's cab, so that the driver can keep track of the lifting height in real time, improve work efficiency, and avoid collision accidents.

[0022] The height measuring gear 8 is welded to the drive shaft 9 of the hoisting drum A3. Proximity switches A10 and B11 are positioned vertically and fixed to the proximity switch bracket 12, ensuring that when the height measuring gear 8 rotates, it passes over proximity switches A10 and B11, generating a signal with a phase difference of 90 degrees. The proximity switch bracket 12 is welded to the output shaft base of the crane drum, maintaining a distance of no more than 8mm from the outer cylindrical gear of the height measuring gear 8. The signal output lines of proximity switches A10 and B11 are connected to the PLC13 module.

[0023] The height measuring gear 8 is made of 12mm thick steel plate, and the outer arc of the gear teeth is polished smooth.

[0024] How to use the lifting height measuring device: The diameter of the overhead crane lifting drum is d, and the height measuring gear (8) has n teeth. Therefore, each lifting equivalent corresponds to a distance L that the lifting drum rolls over.

[0025] As the number of movable pulleys increases, the ratio K of the height H that each equivalent lifting wire rope rises to the distance L that the lifting drum rolls over is:

[0026] After simplifying and reorganizing Formulas 1.1 and 1.2, the lifting distance corresponding to each rise equivalent is determined. :

[0027] Example: PLC: 6ES7315-2AH14-0AB0 Proximity switch: LR12XBN08DNOY enhanced long-range sensor Distance ratio: K=9 Number of teeth on the height measuring gear: n=10 Lifting drum diameter: d=1500mm Increased equivalent:

[0028] The lifting limit switch is set with a high value of 22m and a low value of 2m, and the limit is automatically calibrated for height each shift.

[0029] This invention uses a proximity switch to measure the lifting height of the overhead crane, enabling the crane operator to operate the crane more accurately and safely.

Claims

1. A crane lifting height measuring device, characterized in that: The system includes a hoisting motor A (1), a hoisting motor B (2), a hoisting drum A (3), a hoisting drum B (4), a transmission box (5), a plate hook (6), a hoisting limiter (7), a height measuring gear (8), a transmission shaft (9), a proximity switch A (10), a proximity switch B (11), and an operational PLC (13). The hoisting motor A (1) and the hoisting motor B (2) drive the hoisting drum A (3) and the hoisting drum B (4) through the transmission box (5). The plate hook (6) is connected to the hoisting drum A (3) and the hoisting drum B (4). The hoisting limiter (7) and the height measuring gear (8) are installed on the transmission shaft (9) of the hoisting drum A (3). The proximity switches A (10) and B (11) are fixed side by side on one side of the height measuring gear (8). The hoisting limiter (7), the proximity switch A (10), and the proximity switch B (11) are respectively connected to the operational PLC (13).

2. The overhead crane lifting height measuring device according to claim 1, characterized in that: The drive shaft (9) is coaxially connected to the lifting drum A (3). The height measuring gear (8) is a circular metal plate with gears, which is fixed on the drive shaft (9). When the plate hook (6) is lifted, the drive shaft (9) drives the height measuring gear (8) to rotate synchronously.

3. The overhead crane lifting height measuring device according to claim 1, characterized in that: It also includes a proximity switch bracket (12), with proximity switches A (10) and B (11) fixed side by side to one side of the height measuring gear (8) via the proximity switch bracket (12), and the proximity switch bracket (12) fixed on the base of the crane drum output shaft.

4. The overhead crane lifting height measuring device according to claim 1, characterized in that: The proximity switches A (10) and B (11) are installed side by side to ensure that the phase difference of the signal generated by the height measuring gear (8) passing through the proximity switches A (10) and B (11) when it rotates is 90 degrees.

5. A method for measuring the lifting height of an overhead crane, characterized in that... Includes the following steps: (1) Lifting motor A and lifting motor B drive lifting drum A and lifting drum B to rotate through the transmission box to complete the lifting and lowering operation of the plate hook; (2) The height measuring gear is installed on the drive shaft of the lifting drum A. When the plate hook moves up and down, the height measuring gear rotates accordingly. (3) Proximity switch A and proximity switch B are fixed side by side on one side of the height measuring gear. When the teeth of the height measuring gear pass over the proximity switch, proximity switch A and proximity switch B generate pulse signals and transmit them to the PLC. (4) The PLC analyzes the number of pulse signals and calculates the number of rotations based on the initial settings to achieve real-time monitoring of the lifting and lowering height of the hook. (5) The lifting limit switch is installed on the drive shaft of the lifting drum A. The lifting limit switch signal is connected to the PLC to ensure that no accident of falling or exceeding the height occurs during the operation of the plate hook.

6. The integrated method for converter splash prediction control and temperature measurement according to claim 5, characterized in that: In step (4), the algorithm for calculating the PLC height is as follows: (41) A rising edge signal is generated when the teeth of the height measuring gear slide into the area above proximity switches A and B; a falling edge signal is generated when the teeth of the height measuring gear slide out of the area below proximity switches A and B. (42) Steps for calculating the lifting height of the hook: When the PLC detects that the signals from proximity switch A and proximity switch B are zero, the PLC records a 0 signal. When the height measuring gear rotates, and proximity switch A generates a rising edge signal before proximity switch B, the PLC records signal 11. The PLC detects whether proximity switch B generates a rising edge signal. If it is the first signal after proximity switch A generates a rising edge signal, the PLC records signal 12; otherwise, it is judged as a malfunction and the PLC restores the signal to 0. The PLC detects whether proximity switch A generates a falling edge signal. If it is the first signal after proximity switch B generates a rising edge signal, the PLC records signal 13. Otherwise, it is judged as a malfunction and the PLC restores the signal to 11. The PLC detects whether proximity switch B generates a falling edge signal. If it is the first signal after proximity switch A generates a falling edge signal, the PLC increases the equivalent by 1. Otherwise, it is judged as a malfunction and the PLC restores the signal to 12. (43) Steps for calculating the lowering height of the hook: When the PLC detects that the signals from proximity switch A and proximity switch B are zero, the PLC records a 0 signal. When the height measuring gear rotates, and proximity switch B generates a rising edge signal before proximity switch A, the PLC records signal 21. The PLC detects whether proximity switch A generates a rising edge signal. If it is the first signal after proximity switch B generates a rising edge signal, the PLC records signal 22. Otherwise, it is judged as a malfunction and the PLC restores the signal to 0. The PLC detects whether proximity switch B generates a falling edge signal. If it is the first signal after proximity switch A generates a rising edge signal, the PLC records signal 23. Otherwise, it is judged as a malfunction and the PLC restores the signal to 21. The operational PLC detects whether proximity switch A generates a falling edge signal. If it is the first signal after proximity switch B generates a falling edge signal, the operational PLC increases the equivalent by -1. Otherwise, it is judged as a malfunction, and the operational PLC restores the signal to 22.

7. The integrated method for converter splash prediction control and temperature measurement according to claim 5, characterized in that: It also includes correcting the height value measured by the PLC through the lifting limit switch signal.

Images