Method for detecting loose coils during horizontal movement of hoisted coils

Abstract

The present invention discloses a method for detecting the looseness of a steel coil during the horizontal movement of a steel coil. The method comprises: placing a laser beam detector beside the horizontal lifting route of the steel coil, and before the steel coil lifted by the steel coil lifting machine reaches the position of the laser beam detector, starting the looseness detection process of the steel coil, which comprises: estimating the laser cutoff stroke length to obtain an estimated value of the laser cutoff stroke length; after the steel coil lifted by the steel coil lifting machine leaves the position of the laser beam detector and the laser beam detector is re-lighted, obtaining the actual value of the laser cutoff stroke length; obtaining the difference between the estimated value and the actual value of the laser cutoff stroke length by comparison, if the difference is within a preset allowable range, the steel coil is judged to be normal, otherwise the steel coil is judged to be loose. The method uses a laser beam detector to detect the looseness of the steel coil, which can accurately judge the looseness of the steel coil and prevent the loose tail of the steel coil from causing damage to the on-site equipment during the lifting process.

Description

Technical Field

[0001] The invention relates to a steel coil detection technology in a logistics transportation process, and in particular to a steel coil loose coil detection method in a process of horizontal movement of a hoisted steel coil. Background Art

[0002] The hot-rolled strips finally produced on the hot rolling production line need to be coiled and bundled by the coiler to form steel coils, which are then transported as hot-rolled finished products. The steel coils after being coiled and bundled by the coiler need to go through a lifting and transfer process, which includes: after the steel coils come out of the coiler, they must first be transported on the underground transport chain. After the steel coils reach the lifting and transfer position, the steel coil hoisting machine automatically lifts the steel coils from the underground transport chain to the ground transport chain, and then the ground transport chain transports the steel coils to the subsequent process.

[0003] See also Figure 1 , Figure 1 The figure shows the process of the steel coil hoist automatically hoisting the steel coil from the underground transport chain to the ground transport chain. After the steel coil 2 comes out of the coiler (not shown in the figure), the steel coil hoist 1 vertically lifts the steel coil 2 from the underground transport chain 3. After the steel coil 2 reaches the target height, the steel coil hoist 1 moves horizontally to the top of the ground transport chain 4. Then the steel coil hoist 1 vertically lowers the steel coil 2 until the steel coil 2 is placed on the ground transport chain 4. Then the ground transport chain 4 transports the steel coil 2 to the subsequent process. The hoisting route of the steel coil is as follows Figure 1 As shown by the dotted line, the horizontal route in which the steel coil 2 moves horizontally from above the underground transport chain 3 to above the ground transport chain 4 is the horizontal lifting route of the steel coil.

[0004] However, in the process of transporting steel coils by underground transport chains, the steel coil binding belts may be damaged and loose or fall off, resulting in loose coils. Once the steel coils are loose, the steel coils hoisted by the steel coil hoist will have a long loose coil tail during the steel coil hoisting and transfer process. When the steel coil hoist moves, the loose coil tail will cause damage to the on-site equipment where it passes, such as damaging the grating, breaking the cables and oil pipes, breaking the chain bodies of the underground transport chain and the ground transport chain, etc. Damage to on-site production equipment is often difficult to repair in a short period of time, resulting in a long downtime, which in turn causes greater economic losses.

[0005] In summary, the technical problem to be solved at present is that steel coils may become loose during the production logistics and transportation process. When the loose steel coils are hoisted, the loose tail of the steel coils may cause damage to the on-site equipment where they pass.

[0006] A Chinese patent (CN109816645A) discloses an automatic detection method and process for loose coils, including collecting depth data on the surface of the coil, and also including the following steps: after denoising the depth data, mapping the depth map to a grayscale image of the same size; using the Soble operator to perform image gradient detection on the grayscale image; performing connected domain analysis on the edge, and removing the noise area through the foreground pixel area; using the image gradient in the edge area of ​​the image to find the opposite gradient point pairs at the edge; using the distance between the point pairs and combining the depth information to determine whether the coil is loose. However, this method uses visual images to analyze the edge of the coil to determine whether the coil is loose. Its implementation process requires a relatively complex visual image analysis system and a large amount of data support. The implementation process is very cumbersome and is not suitable for large-scale promotion in production sites. Summary of the invention

[0007] The purpose of the present invention is to provide a method for detecting loose coils of steel coils during the horizontal movement of the steel coils during hoisting. The method uses a laser beam detector to detect the loose coil situation of the steel coils, which can accurately judge the loose coil situation of the steel coils and avoid damage to on-site equipment caused by the loose coil tail of the steel coil during the hoisting process.

[0008] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0009] A method for detecting loose coils of steel coils during horizontal movement of the steel coils, wherein a laser beam detector is arranged beside the horizontal lifting route of the steel coils, and a laser transmitter and a laser receiver of the laser beam detector are respectively arranged on both sides of the horizontal lifting route of the steel coils, and the laser transmitter and the laser receiver are arranged to beam against each other;

[0010] The steel coil loose coil detection method comprises the following steps:

[0011] Step 1: At the lifting starting position, the steel coil hoist lifts the steel coil and lifts it to the target height;

[0012] When the steel coil is at the target height position, the horizontal height of the laser line emitted by the laser transmitter of the laser beam detector to the laser receiver is between the lowest position of the central coil hole of the steel coil and the lowest position of the steel coil;

[0013] Step 2, the steel coil hoisting machine horizontally moves the hoisted steel coil along the steel coil horizontal hoisting route toward the hoisting target position;

[0014] Step 3, before the steel coil hoisted by the steel coil hoist reaches the position of the laser beam detector, start the steel coil loose coil detection process;

[0015] The steel coil loose coil detection process includes:

[0016] Step 3.1, the laser beam detector performs a self-check of the light signal. If the light signal self-check is normal, step 3.2 is executed. Otherwise, the operation of the steel coil hoisting machine is interrupted and an alarm signal is issued.

[0017] Step 3.2, estimating the laser cutoff stroke length to obtain an estimated value of the laser cutoff stroke length;

[0018] The laser cutoff stroke length is: the horizontal movement stroke length of the steel coil hoist from the time when the steel coil starts to cut off the laser beam detector to the time when the laser beam detector is re-transmitted after the steel coil leaves;

[0019] Step 3.3, after the steel coil hoisted by the steel coil hoist passes the position of the laser beam detector, the actual value of the laser cutoff stroke length is obtained;

[0020] Step 3.4, obtaining the difference between the estimated value and the actual value of the laser interruption stroke length by comparison, if the difference is within a preset allowable range, the steel coil is determined to be normal, otherwise, the steel coil is determined to be loose.

[0021] Furthermore, an angle is set between the laser line emitted by the laser transmitter of the laser beam detector to the laser receiver and the projection line of the central axis of the steel coil on the horizontal plane.

[0022] Furthermore, the step 3 also includes:

[0023] For the steel coil loosening detection process, a detection travel window and a detection timing window are set. When the travel position of the steel coil hoisting machine is within the detection travel window, and the timing time after entering the detection travel window is within the detection timing window, the steel coil loosening detection process is started, otherwise the steel coil loosening detection process is stopped;

[0024] The detection travel window is arranged on the upstream side of the position of the laser beam detector in the horizontal lifting route of the steel coil;

[0025] The timing start travel point of the detection timing window is the starting travel point of the detection travel window.

[0026] Furthermore, the step 3 also includes: the starting point of the detection travel window is 3 meters upstream of the location of the laser beam detector, and the ending point of the detection travel window is the location of the laser beam detector.

[0027] Furthermore, the step 3 also includes: the timing time of the detection timing window is set to 3 seconds.

[0028] Furthermore, the step 3.2 further includes: obtaining an estimated value of the laser cutoff stroke length according to an estimation formula, wherein the estimation formula is:

[0029]

[0030] Wherein, L is the estimated value of the laser cutoff stroke length, r is the radius of the steel coil, w is the width of the steel coil, θ is the acute angle between the laser line emitted by the laser beam detector and the projection line of the center axis of the steel coil on the horizontal plane, h is the vertical distance between the horizontal plane where the center axis of the steel coil is located and the horizontal plane where the laser line emitted by the laser beam detector is located, and Δx is the allowable deviation value.

[0031] Furthermore, the step 3.3 also includes: obtaining the laser cutoff time of the laser cross-beam detector, obtaining the average travel speed of the steel coil hoist, multiplying the laser cutoff time of the laser cross-beam detector by the average travel speed of the steel coil hoist, and the obtained length value is used as the actual value of the laser cutoff stroke length.

[0032] Furthermore, the step 3.4 also includes: if it is determined that the steel coil is loose, interrupting the operation of the steel coil hoisting machine and sending an alarm signal.

[0033] In the steel coil loosening detection method of the present invention, a laser cross-beam detector is installed beside the horizontal lifting route of the steel coil, and the laser cross-beam detector is used to detect the passing steel coil. Whether the steel coil is loose is determined according to the length of time that the steel coil blocks the laser cross-beam detector. The difference between the estimated value and the actual value of the laser blocking stroke length is obtained by comparison. If the difference is within a preset allowable range, the steel coil is determined to be normal, and the steel coil hoisting machine continues to lift the steel coil toward the lifting target position. Otherwise, the steel coil is determined to be loose, and the operation of the steel coil hoisting machine is interrupted, thereby effectively avoiding damage to on-site equipment caused by the loose coil tail due to the loose steel coil during the lifting process. In order to prevent the accidental shading signal of the laser beam detector from causing the misjudgment of the steel coil loosening, a detection travel window and a detection timing window are also set for the steel coil loosening detection process. The steel coil loosening detection process will only be started when the travel position of the steel coil hoist is within the detection travel window and the timing time after entering the detection travel window is also within the detection timing window, otherwise the steel coil loosening detection process will be stopped.

[0034] The steel coil loosening detection method of the present invention has the beneficial effect compared with the prior art: in the steel coil loosening detection method of the present invention, a laser cross-beam detector is used to detect the loosening of the steel coil, and the accuracy of detecting and judging the loosening of the steel coil is high and the reliability is good, thereby effectively avoiding the damage to the on-site equipment caused by the loose coil tail due to the loosening of the steel coil during the lifting process of the steel coil; in addition, the steel coil loosening detection method of the present invention only needs to add a laser cross-beam detector on the basis of the original equipment to realize the detection and judgment of the loosening of the steel coil, which is simple and convenient to implement and the equipment cost required is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of a steel coil hoisting machine hoisting a steel coil from an underground transport chain to a ground transport chain in a production site under existing technical conditions;

[0036] Figure 2 The figure is a schematic diagram of the implementation of the method for detecting loose coils of steel coils during the horizontal movement of the steel coils in the present invention at a production site. In the figure, a laser beam detector is arranged on the horizontal lifting route of the steel coils.

[0037] Figure 3 for Figure 2 A top view of the area indicated by arrow B;

[0038] Figure 4 Schematic diagram of the corresponding side view and top view of the steel coil being hoisted, in which the dotted line indicated by the arrow F is the position where the laser line emitted by the laser beam detector sweeps;

[0039] Figure 5 It is a schematic diagram of estimating the laser interruption stroke length in the steel coil loose coil detection method of the present invention;

[0040] Figure 6 The present invention is a flow chart of a method for detecting loose coils in a process of hoisting a steel coil and moving it horizontally.

[0041] In the figure: 1- steel coil hoisting machine, 2- steel coil, 3- underground transport chain, 4- ground transport chain, 5- laser beam detector, 51- laser transmitter, 52- laser receiver. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments:

[0043] See also Figures 2 to 6 The present embodiment is a method for detecting loose coils in the process of horizontal movement of hoisted steel coils. The method can detect the horizontally moving steel coils and determine whether the steel coils are loose, thereby preventing the loose coils from causing damage to on-site equipment.

[0044] It should be noted that the steel coil loose coil detection method of this embodiment can only be applied to the case where the horizontal movement direction of the steel coil hoisting machine is perpendicular to the central axis of the steel coil.

[0045] See also Figure 2 and Figure 3 A laser beam detector 5 is arranged beside the horizontal lifting route of the steel coil. The laser emitter 51 and the laser receiver 52 of the laser beam detector 5 are respectively arranged on both sides of the horizontal lifting route of the steel coil, and the laser emitter 51 and the laser receiver 52 are arranged to beam against each other.

[0046] The laser cross-beam detector 5 is an existing device, which includes a laser emitter 51 and a laser receiver 52. The function of the laser cross-beam detector 5 is to determine whether there is a light-shielding object between the laser emitter 51 and the laser receiver 52. Specifically, when the laser cross-beam detector 5 is used, the laser emitter 51 and the laser receiver 52 of the laser cross-beam detector 5 are respectively placed on both sides of the target detection area, and the laser emitter 51 and the laser receiver 52 are arranged to face each other. If there is no light-shielding object between the laser emitter 51 and the laser receiver 52, the laser emitted by the laser emitter 51 can be received by the laser receiver 52, and the laser cross-beam detector 5 sends a light-through signal. If there is a light-shielding object between the laser emitter 51 and the laser receiver 52, the laser emitted by the laser emitter 51 cannot be received by the laser receiver 52, and the laser cross-beam detector 5 sends a light-shielding signal. In this embodiment, in the computer system at the production site, the light-through signal or light-blocking signal emitted by the laser beam detector 5 is represented by a one-bit binary code, the light-through signal is represented by "1", and the light-blocking signal is represented by "0". In the specific program control, the direction of the program is controlled according to the binary code.

[0047] The laser emitter 51 and the laser receiver 52 are arranged facing each other, which means that the laser emitting end of the laser emitter 51 faces the laser receiver 52, and the laser receiving end of the laser receiver 52 faces the laser emitter 51. When there is no obstruction between the laser emitter 51 and the laser receiver 52, the laser energy emitted by the laser emitter 51 can be completely received by the laser receiver 52, so that the laser facing detector 5 sends a light transmission signal.

[0048] See also Figure 2 and Figure 3 , the laser emitter 51 and the laser receiver 52 of the laser beam detector 5 are arranged to beam against each other. Figure 2 In FIG. 5 , the dotted line indicated by the arrow H1 is the laser line emitted by the laser emitter 51 of the laser beam detector 5 to the laser receiver 52. Figure 3 In the figure, the dotted line indicated by the arrow H2 is the laser line emitted by the laser emitter 51 of the laser beam detector 5 to the laser receiver 52.

[0049] See also Figure 3 Preferably, an angle is set between the laser line emitted by the laser emitter 51 of the laser beam detector 5 to the laser receiver 52 and the projection line of the central axis of the steel coil 2 on the horizontal plane. The angle is usually set between 15 and 30 degrees. The specific angle value can be determined according to the site environment of the operation area. The purpose of setting the angle is to: 1) prevent the laser from passing through the gap between the coil layers after the steel coil is unwound, resulting in detection errors; 2) detect the tailing of the steel coil. When the steel coil tails, it will also block the laser and make the blocking stroke longer.

[0050] See also Figure 6 The steel coil loose coil detection method of this embodiment includes the following steps:

[0051] Step 1: At the underground transport chain 3 serving as the lifting starting position, the steel coil hoist 1 lifts the steel coil 2 and elevates it to a preset target height.

[0052] See also Figure 2 , the target height needs to be preset, and the target height should match the installation height of the laser beam detector 5. Specifically, when the steel coil 2 is at the target height position, the horizontal height of the laser line emitted by the laser emitter 51 of the laser beam detector 5 to the laser receiver 52 is between the lowest position of the central coil hole of the steel coil 2 and the lowest position of the entire steel coil 2, such as Figure 2 The dotted line indicated by the middle arrow H1 indicates that at this height position, when the steel coil 2 moves horizontally past the laser beam detector 5, the steel coil 2 can normally and smoothly block the light signal of the laser beam detector 5. If the target height for lifting the steel coil 2 is set too high, and the installation height of the laser beam detector 5 is lower than the lowest position of the entire steel coil 2, when the steel coil 2 moves horizontally past the laser beam detector 5, the steel coil 2 cannot block the light signal of the laser beam detector 5. If the target height for lifting the steel coil 2 is set too low, and the installation height of the laser beam detector 5 is higher than the lowest position of the center coil hole of the steel coil 2, when the steel coil 2 moves horizontally past the laser beam detector 5, the laser beam detector 5 will generate a light blocking signal at first, and when the center coil hole of the steel coil 2 passes through the laser beam detector 5, a light blocking signal will be generated, and when the center coil hole of the steel coil 2 leaves the laser beam detector 5, a light blocking signal will be generated again, thereby making the light blocking signal of the laser beam detector 5 discontinuous, and in the subsequent steps, it is impossible to judge the laser blocking stroke length based on the light blocking signal.

[0053] Step 2: the steel coil hoisting machine 1 moves the hoisted steel coil 2 horizontally along the steel coil horizontal hoisting route toward the ground transport chain 4 which is the hoisting target position.

[0054] Step 3, before the steel coil 2 hoisted by the steel coil hoisting machine 1 reaches the position of the laser beam detector 5, the steel coil loosening detection process is started.

[0055] The steel coil loose coil detection process includes:

[0056] Step 3.1, the laser beam detector 5 performs a self-check of the light signal. If the light signal of the laser beam detector 5 is normal, step 3.2 is executed. Otherwise, the operation of the steel coil hoisting machine 1 is interrupted and an alarm signal is issued.

[0057] Specifically, the light-through signal self-check is to determine whether the laser beam detector 5 is in a light-through state. If so, the light-through signal of the laser beam detector 5 is considered normal. If not, the light-through signal of the laser beam detector 5 is considered abnormal. In the case of an abnormal light-through signal, the laser beam detector 5 cannot detect the steel coil 2, so it is necessary to interrupt the operation of the steel coil hoist 1 and send out an alarm signal, and restart the steel coil hoist 1 after the operator confirms the reset.

[0058] Step 3.2, the computer system at the production site automatically estimates the laser cutoff stroke length to obtain an estimated value of the laser cutoff stroke length;

[0059] The laser cutoff stroke length refers to: when the steel coil 2 lifted by the steel coil hoist 1 passes through the laser beam detector 5, the horizontal movement stroke length of the steel coil hoist 1 starts from the time when the steel coil 2 begins to cut off the light signal of the laser beam detector 5 until the laser beam detector 5 turns on again after the steel coil 2 leaves.

[0060] In this embodiment, the estimated value of the laser cutoff stroke length is obtained according to an estimation formula, which is:

[0061]

[0062] Wherein, L is the estimated value of the laser cutoff stroke length, r is the radius of the steel coil, w is the width of the steel coil, θ is the acute angle between the laser line emitted by the laser beam detector and the projection line of the center axis of the steel coil on the horizontal plane, h is the vertical distance between the horizontal plane where the center axis of the steel coil is located and the horizontal plane where the laser line emitted by the laser beam detector is located, and Δx is the allowable deviation value.

[0063] The radius r, width w and other steel coil related parameter information used in estimating the laser interruption stroke length are automatically acquired by the computer system at the production site through the production logistics information system.

[0064] See also Figure 4 and Figure 5 , the following is a detailed explanation of the reason for the estimation formula of the estimated value of the laser interruption stroke length:

[0065] See also Figure 4As mentioned above, when the steel coil 2 is at the target height, the horizontal height of the laser line emitted by the laser emitter 51 of the laser beam detector 5 to the laser receiver 52 is between the lowest position of the center coil hole of the steel coil 2 and the lowest position of the entire steel coil 2. When the steel coil 2 passes the laser beam detector 5, the area between the lowest position of the center coil hole of the steel coil 2 and the lowest position of the entire steel coil 2 will block the laser line emitted by the laser beam detector 5. From the side view of the horizontal lifting route of the steel coil, the position where the laser line sweeps on the end surface of the steel coil 2 is as follows: Figure 4 The dashed line indicated by the arrow F in the middle shows the cross section of the coil 2 at the position swept by the laser line from the top view of the horizontal lifting route of the coil. Figure 4 The gray area indicated by the arrow G.

[0066] See also Figure 5 When the steel coil 2 moves to the laser beam detector 5 and just blocks the laser line, the position of the steel coil 2 is as follows: Figure 5 As indicated by the arrow D in the figure, when the laser beam detector 5 is just turned on again after the steel coil 2 leaves, the position of the steel coil 2 is as follows: Figure 5 Indicated by the arrow E. The distance L' between the center axes of the steel coil 2 at the two positions can be regarded as the laser interruption stroke length, L' = l m / 2+l m / 2+C w = l m +C w , where l m C is the horizontal moving length of the steel coil 2 when the laser line emitted by the laser beam detector 5 sweeps across the end surface of the steel coil 2, w It is the horizontal movement length of the steel coil 2 when the laser line emitted by the laser beam detector 5 sweeps across the wide surface of the steel coil 2.

[0067] According to the Pythagorean theorem, we can conclude that:

[0068] According to the principle of trigonometric function, we can conclude that: C w =w×tanθ;

[0069] but

[0070] Then, set a Δx as the allowable deviation value, add another Δx to L', and use the added value as the estimated value L of the laser cutoff stroke length, that is, L = L' + Δx, and finally get the estimated formula of the laser cutoff stroke length

[0071] Step 3.3, after the steel coil 2 hoisted by the steel coil hoisting machine 1 passes the position of the laser beam detector 5, the actual value of the laser cutoff stroke length is obtained. When the steel coil 2 hoisted by the steel coil hoisting machine 1 reaches the position of the laser beam detector 5, the laser beam detector 5 is first shielded, and when the steel coil 2 leaves the position of the laser beam detector 5, the laser beam detector 5 resumes light transmission.

[0072] The process of obtaining the actual value of the laser cutoff stroke length includes: obtaining the laser cutoff time of the laser cross-beam detector 5, obtaining the average travel speed of the steel coil hoist 1, multiplying the laser cutoff time of the laser cross-beam detector 5 by the average travel speed of the steel coil hoist 1, and the obtained length value is used as the actual value of the laser cutoff stroke length.

[0073] The laser cutoff time is the time difference between the moment when the laser beam detector 5 starts to be cut off from the light signal by the steel coil 2 and the moment when the laser beam detector 5 resumes the light signal after the steel coil 2 leaves, and the time difference can be obtained by the computer system of the production site through software. Specifically, a software timer can be set in the computer system, and when the laser beam detector 5 starts to be cut off from the light signal by the steel coil 2, the software timer starts timing, and when the laser beam detector 5 resumes the light signal after the steel coil 2 leaves, the software timer stops timing, thereby obtaining the laser cutoff time.

[0074] The average travel speed of the steel coil hoist 1 can be obtained through the main controller (usually a PLC controller) of the steel coil hoist 1. Specifically, the computer system at the production site is connected to the main controller of the steel coil hoist 1 through electrical signals, and the computer system can obtain the operation data of the steel coil hoist 1 through the main controller of the steel coil hoist 1, including the average travel speed of the steel coil hoist 1.

[0075] Step 3.4, by comparing the difference between the estimated value and the actual value of the laser cutoff stroke length, if the difference is within the preset allowable range, it is determined that the steel coil 2 is normal, and the steel coil hoisting machine 1 continues to hoist the steel coil 2 toward the hoisting target position, otherwise, it is determined that the steel coil 2 is loose. If it is determined that the steel coil 2 is loose, the operation of the steel coil hoisting machine 1 is interrupted and an alarm signal is issued, and the alarm signal is an audible and visual alarm signal issued on the human-machine interface.

[0076] In this embodiment, the human-computer interaction interface is a computer screen, and in other embodiments, the human-computer interaction interface may also be an operation panel.

[0077] For further optimization, in order to prevent the accidental shading signal of the laser beam detector 5 from causing the misjudgment of the steel coil loosening, in step 3, a detection travel window and a detection timing window are also set for the steel coil loosening detection process.

[0078] The detection travel window is set at the upstream side of the position of the laser beam detector 5 in the horizontal lifting route of the steel coil. In this embodiment, the starting travel point of the detection travel window is 3 meters upstream of the position of the laser beam detector 5, and the ending travel point of the detection travel window is the position of the laser beam detector 5.

[0079] The timing time of the detection timing window is set to 3 seconds, and the starting stroke point of the detection stroke window is used as the timing start stroke point of the detection timing window. That is, when the steel coil hoisting machine 1 hoists the steel coil 2 into the detection stroke window, the detection timing window starts timing, and when the detection timing window timing reaches 3 seconds, the detection timing window ends.

[0080] In this embodiment, the steel coil loosening detection process is started only when the travel position of the steel coil hoisting machine 1 is within the detection travel window and the timing time after entering the detection travel window is also within the detection timing window, otherwise the steel coil loosening detection process is stopped. In other words, as long as one of the window conditions in the detection travel window and the detection timing window is not met, the steel coil loosening detection process will not be started.

[0081] The purpose of setting the detection travel window and the detection timing window is to prevent the accidental interference signal of the laser beam detector 5 from causing the false judgment of the steel coil loosening. For example, when the steel coil 2 is not within the detection travel window, or the timing time is not within the detection timing window, the steel coil loosening detection process will not be started, even if someone passes by the laser beam detector 5 and causes the laser line to be blocked, the light blocking signal at this time will not be ignored, thereby avoiding the false judgment of the steel coil loosening.

[0082] In the steel coil loosening detection method of this embodiment, a laser beam detector 5 is placed beside the horizontal lifting route of the steel coil, and the laser beam detector 5 is used to detect the steel coil 2 passing by. According to the length of the shielding time of the steel coil 2 to the laser beam detector 5, it is judged whether the steel coil is loose. The accuracy of the detection and judgment of the steel coil loosening is high and the reliability is good, thereby effectively avoiding the damage to the on-site equipment caused by the loose coil tail caused by the loose steel coil 2 during the lifting process. In addition, the steel coil loosening detection method of this embodiment only needs to add a laser beam detector 5 on the basis of the original equipment to realize the detection and judgment of the steel coil loosening, which is simple and convenient to implement and requires low equipment cost.

[0083] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting loose coils during horizontal movement of hoisted coils, characterized in that: A laser beam detector is placed beside the horizontal lifting route of the steel coil, and the laser emitter and laser receiver of the laser beam detector are respectively placed on both sides of the horizontal lifting route of the steel coil, and the laser emitter and the laser receiver are arranged to face each other; an angle is set between the laser line emitted by the laser emitter of the laser beam detector to the laser receiver and the projection line of the central axis of the steel coil on the horizontal plane; The steel coil loose coil detection method comprises the following steps: Step 1: At the lifting starting position, the steel coil hoist lifts the steel coil and lifts it to the target height; When the steel coil is at the target height position, the horizontal height of the laser line emitted by the laser transmitter of the laser beam detector to the laser receiver is between the lowest position of the central coil hole of the steel coil and the lowest position of the steel coil; Step 2, the steel coil hoisting machine horizontally moves the hoisted steel coil along the steel coil horizontal hoisting route toward the hoisting target position; Step 3, before the steel coil hoisted by the steel coil hoist reaches the position of the laser beam detector, start the steel coil loose coil detection process; The steel coil loose coil detection process includes: Step 3.1, the laser beam detector performs a self-check of the light signal. If the light signal self-check is normal, step 3.2 is executed. Otherwise, the operation of the steel coil hoisting machine is interrupted and an alarm signal is issued. Step 3.2, estimating the laser cutoff stroke length to obtain an estimated value of the laser cutoff stroke length; The laser cutoff stroke length is: the horizontal movement stroke length of the steel coil hoist from the time when the steel coil starts to cut off the laser beam detector to the time when the laser beam detector is re-transmitted after the steel coil leaves; The estimated value of the laser cutoff stroke length is obtained according to the estimation formula, and the estimation formula is: Wherein, L is the estimated value of the laser cutoff stroke length, r is the radius of the steel coil, w is the width of the steel coil, θ is the acute angle between the laser line emitted by the laser beam detector and the projection line of the center axis of the steel coil on the horizontal plane, h is the vertical distance between the horizontal plane where the center axis of the steel coil is located and the horizontal plane where the laser line emitted by the laser beam detector is located, and Δx is the allowable deviation value; Step 3.3, after the steel coil hoisted by the steel coil hoist passes the position of the laser beam detector, the actual value of the laser cutoff stroke length is obtained; Step 3.4, obtaining the difference between the estimated value and the actual value of the laser interruption stroke length by comparison, if the difference is within a preset allowable range, it is determined that the steel coil is normal, otherwise, it is determined that the steel coil is loose; For the steel coil loosening detection process, a detection travel window and a detection timing window are set. When the travel position of the steel coil hoisting machine is within the detection travel window, and the timing time after entering the detection travel window is within the detection timing window, the steel coil loosening detection process is started, otherwise the steel coil loosening detection process is stopped; The detection travel window is arranged on the upstream side of the position of the laser beam detector in the horizontal lifting route of the steel coil; The timing start travel point of the detection timing window is the starting travel point of the detection travel window.

2. The method for detecting loose coils during horizontal movement of a hoisted coil according to claim 1, characterized in that: The step 3 also includes: the starting point of the detection travel window is 3 meters upstream of the location of the laser beam detector, and the ending point of the detection travel window is the location of the laser beam detector.

3. The method for detecting loose coils during horizontal movement of a hoisted coil according to claim 1, characterized in that: The step 3 also includes: the timing time of the detection timing window is set to 3 seconds.

4. The method for detecting loose coils during horizontal movement of a hoisted coil according to claim 1, characterized in that: The step 3.3 also includes: obtaining the laser cutoff time of the laser cross-beam detector, obtaining the average travel speed of the steel coil hoist, multiplying the laser cutoff time of the laser cross-beam detector by the average travel speed of the steel coil hoist, and the obtained length value is used as the actual value of the laser cutoff stroke length.

5. The method for detecting loose coils during horizontal movement of a hoisted steel coil according to claim 1, characterized in that: The step 3.4 also includes: if it is determined that the steel coil is loose, interrupting the operation of the steel coil hoisting machine and sending an alarm signal.

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