JP2019189398A - Overhead crane for carrying steel billet - Google Patents

Abstract

To provide an overhead crane for carrying a steel billet that uses a distance sensor and can grasp the uppermost one of a number of stacked steel pieces quickly and accurately with a simple mechanism.SOLUTION: For the short direction of a steel billet SB, the inclination of the center of the steel billet SB in the short direction and the steel billet SB relative to the crane parallel line are calculated by measuring the dimensions of both ends of the two lines in the short direction with two wide-area laser distance sensors PX1 and PX2. For the long direction, wide-range laser distance sensors PY1 and PY2 for detecting the longitudinal direction are installed on two cranes near the upper end of the long side of the steel billet SB and above the short side of the opposite long side. These two long direction distance sensors PY1, PY2 calculate the dimension center in the longitudinal direction from the position dimensions of the respective longitudinal edges detected by the wide-area laser distance sensors PY1 and PY2 for detecting the longitudinal direction by being placed on the same line of the parallel line of the crane.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a billet-carrying overhead crane that is applied when, for example, a high-temperature billet slab is carried by an overhead crane during the manufacture of a steel product, and in particular, automatically detects the billet grab position. The present invention relates to a billet overhead crane.

The billet slab cast in the steelworks is used to lower the hot billet slab to an appropriate temperature before stocking the billet slab for the next hot rolling process before flowing to the next hot rolling process. It is stored and managed in the yard.
The high temperature billet slab in this yard is transported by manipulating a dedicated overhead crane for billet transportation equipped with a special billet slab tong to grab the billet slab. Therefore, there is a demand for automated operation and efficiency of cranes.

  By the way, when a steel slab slab is gripped by a steel slab slab tongue and lifted by a crane, if the steel slab slab is not gripped at the center of gravity of the steel slab slab, the suspended load may be inclined or fallen. For this reason, in the manned operation, the center of gravity is picked up by the eye measurement, but in the automatic operation, a sensor for detecting the center of gravity is required.

  The slab slabs stored in the slab yard are stacked and stored in a number of layers, and are gripped for each topmost piece, but the top slab slab and the bottom slab slab are beautiful. When the center of gravity of the upper slab slab is measured, if the position of the lower slab slab is measured, the position of the center of gravity is erroneously calculated. .

  By the way, in order to cope with such problems, conventionally, when a steel slab is transported by an overhead crane, in order to detect the shape of the steel slab and the position of its center of gravity, an image is taken from above the steel slab by a camera. The image processing is performed to extract the captured image separately from the plane and side images of the steel slab, and the plane distance between the camera and the steel slab and the angle between the optical axis of the camera and the bottom of the steel slab are determined. Calculate and calculate the center point of the steel slab from the plane image and the height of the steel slab from the side image, respectively, determine the center of gravity of the steel slab from these center point and height, There has been proposed a method of automatically lifting a steel slab that controls the position of (see Patent Document 1, for example, if necessary).

Japanese Patent Laid-Open No. 7-330287

  However, the conventional method using a camera has a problem that it takes time to process an image.

  In addition, the billet slab carried to the slab yard is brought into the hot billet slab that has just been cast in the casting line. High-temperature billet slabs generated strong radiant heat, and measures were required to prevent the sensor from being damaged by this radiant heat.

  In view of the problems of the above-described conventional billet-carrying overhead crane, the present invention uses a distance sensor and uses a simple mechanism to quickly and accurately stack the steel bills in a number of stages. It is a first object of the present invention to provide a billet-carrying overhead crane capable of gripping one of the upper tiers.

  The second object of the present invention is to provide a billet-carrying overhead crane that can prevent the sensor from being damaged by strong radiant heat generated by a high-temperature billet.

  In order to achieve the first object, the billet overhead crane of the present invention is equipped with a plurality of wide area laser distance sensors for measuring the billet size on the crane of the billet overhead crane. A billet overhead crane that moves to the upper surface of the billet to be handled and measures the size of the billet slab from the upper surface of the billet using a wide-range laser distance sensor. By measuring the dimensions of both sides in the short direction of the two lines with a single wide-area laser distance sensor, the center of the short direction of the steel piece and the inclination of the steel piece with respect to the crane parallel line are calculated. Wide range laser distance sensors for detecting the long direction are provided on two cranes near the upper side of the long side of the steel piece and near the upper side of the short side on the opposite side. Pieces of long The distance sensor is located on the same line as the parallel line of the crane, so that the center of dimension in the longitudinal direction is determined from the position dimension of each longitudinal edge detected by the wide-area laser distance sensor for detecting the longitudinal direction. , And the center position of the steel piece transport so that the center position of the billet transfer tongue is aligned with the center position of the steel piece. Equipped with a series of systems to move the steel and grab the billet.

  In this case, if the short direction plane distance between the short direction center line of the steel piece and the wide range laser distance sensor mounting position for detecting the long direction is large, and the steel piece has a large inclination angle with respect to the crane parallel line, From the trigonometric function of the short plane distance between the short direction center line of the piece and the wide area laser distance sensor mounting position for detecting the long direction and the inclination angle of the steel piece relative to the crane parallel line, the wide area laser distance sensor for detecting the long direction A correction method for correcting the detected center position in the longitudinal direction and a method for processing the inclination angle of the billet that issues an alarm when the billet has an excessively large inclination angle with respect to the crane parallel line can be provided.

  Also, when measuring stacked steel slabs from the upper crane with a wide-area laser distance sensor, do not measure the position below the dimension below the thickness of the steel slab to be measured from the top steel slab height. By doing so, only the uppermost steel piece can be measured.

  In order to achieve the second object, the billet-carrying overhead crane of the present invention is a billet-carrying overhead crane provided with a wide-area laser distance sensor for billet measurement attached to the overhead crane, It is attached in the form of looking down on the steel piece placed on the ground from above, and the wide area laser distance sensor is covered with a heat insulating cover provided with a cooling device, and the heat insulating cover is for laser irradiation of the wide area laser distance sensor. A peephole is provided, and a thermal shutter is provided in the peephole, the thermal shutter opens the thermal shutter only at the moment when the wide-area laser distance sensor performs measurement, and allows laser light to pass through the peephole, The thermal shutter was always closed, and once the shutter was opened, the shutter was not opened until after a certain period of time. And wherein the door.

First, the billet overhead crane of the present invention moves the crane onto the billet based on the position information of the billet to be grabbed.
A wide-area laser distance sensor for measuring the width of one side in the X-axis direction with a steel piece and a wide-area laser distance sensor for measuring the width in the direction perpendicular to the crane are attached to the crane.
The position of the center of gravity of the steel slab is a shape that approximates the center position of the plane as viewed from above, so it is directly above the center position of the dimension measured by the X-axis and Y-axis wide-area laser distance sensors In addition, the crane traverse and travel are moved to stop the positioning so that the center position of the crane hoisting device comes, and it can be gripped at the position of the center of gravity of the steel slab by lowering and gripping at this position.

  In this case, since the thickness of the steel slabs handled in the yard is known in advance, in order to reliably measure only the shape, dimensions, and position of the uppermost stage of the stacked steel slabs, The detection object slightly lower than the height lower than the height corresponding to the thickness of the piece is not detected, so that the steel pieces in the second and lower stages from the top are not detected.

The above-mentioned wide-area laser distance sensor is stored in a radiant heat shielding storage box from the radiant heat received from the slab in order to attach the slab to a position where the line of sight is good. A small window for light transmission is provided, and this small window is normally closed by a heat-insulating movable shutter, and the heat-insulating movable shutter is opened and measured only at the moment when the wide-area laser distance sensor is measured.
This storage box is provided with a ventilation fan for cooling the inside of the storage box, the wide-area laser distance sensor, and the heat-insulating shutter.
In order to prevent the temperature of the wide-area laser distance sensor from rising due to frequent opening of the heat-resistant movable shutter, once the heat-resistant movable shutter is opened and closed, it takes time to lower the surface temperature of the wide-area laser distance sensor to a certain temperature. Until, the heat-proof movable shutter is kept from opening.

In steelmaking lines that are becoming increasingly automated, billet cranes have been handled by hand-operated cranes because if they do not grab the center of gravity, they can lead to accidents such as falling loads.
INDUSTRIAL APPLICABILITY The present invention is a technique that can automatically measure the position of the center of gravity, and is effective in carrying by crane automatic operation.
Also, even in cranes that are operated manually, the present invention can be used to accurately detect the center of gravity position of the load, so that it is possible to prevent an accident in which the suspended load falls due to unbalanced center of gravity position of the suspended load and improve safety. become.

It is a schematic explanatory drawing of the billet overhead crane for billet slab yards. It is explanatory drawing of the assumption method of the dimension center position of a steel piece slab. It is explanatory drawing of the method of detecting the edge side of a steel piece slab. It is sectional drawing of the heat insulation cover of a wide region laser distance sensor, and is explanatory drawing of the state which has closed the heat insulation shutter. It is sectional structure explanatory drawing of the state in which the heat insulating shutter of the heat insulating cover was opened. It is a time chart figure of opening and closing of the heat insulating shutter of a heat insulating cover.

  Hereinafter, an embodiment of an overhead crane for billet conveyance according to the present invention will be described based on the drawings, taking as an example a billet overhead crane for a billet slab yard handling a billet slab.

  In the steelmaking process, a thick plate manufactured by continuous speed casting equipment is cut into a certain size and is a long, thick flat plate shape. It is carried into a slab slab yard at a high temperature before flowing into the next rolling process. The stock is once stocked in the billet slab yard.

In the billet slab yard, as shown in FIG. 1, a dedicated crane CR for conveying the billet slab is arranged. A dedicated tongue TG for holding the steel slab slab is suspended from the crane CR.
This tong TG grasps the side surface in the short direction of the slab slab SB, and normally conveys it one by one.
The billet slab SB that has flowed from the upstream is stored by being stacked on the slab storage pallet PL by the crane CR, and when the billet slab is supplied to the downstream process, it is loaded on the uppermost stage of the slab storage pallet PL. The steel slab slab SB is gripped and transported to the payout site in the downstream process by the crane CR.

  In the above work process, when the steel slab SB is gripped by the tongue TG, if the steel slab SB is not lifted by the center of gravity of the steel slab SB, the steel slab SB is inclined when the steel slab SB is lifted by the crane CR. There is a risk of dropping the slab SB. For this reason, in order to improve the safety when the crane CR is automatically operated or when the crane CR is manually moved, it is important to grasp the position of the center of gravity of the billet slab SB to be transported.

For this reason, two wide-area laser distance sensors PX1 and PX2 are attached to both ends of the club of the crane CR to measure the short dimension of the steel slab SB, and the two short lines PX1L shown in FIG. , PX2L can be measured.
In addition, in order to measure the longitudinal direction of the steel slab SB, two wide-area laser distance sensors PY1, PY2 are mounted on the same longitudinal line at both ends of the club, and one end of each longitudinal direction is attached. It can be detected.
Here, the wide-area laser distance sensors PX1 and PX2 and the wide-area laser distance sensors PY1 and PY2 include a general-purpose wide-area laser distance sensor (for example, a range sensor UXM-30LX manufactured by Hokuyo Electric Co., Ltd.) capable of wide-area scanning with a wide angle of view. ) Can be used.

In the case of automatically operating the crane CR, the automatic operation computer of the crane CR stores the grabbing fixed position of the billet slab on the conveyor on which the billet slab SB is brought into the slab yard and the position of the pallet PL.
By moving the crane CR to the stored position, all of the four wide-area laser distance sensors PX1, PX2, PY1, and PY2 enter the measurable range of the billet slab SB to be transported.
At this time, the four wide-area laser distance sensors PX1, PX2, PY1, and PY2 measure the center position of the slab slab, and the center position of the tong TG and the slab slab SB are regarded as the center of gravity position. The crane CR is moved so as to match the center position of the slab, and the uppermost steel slab SB is gripped.

  As shown in FIG. 2, the two wide-area laser distance sensors PX1 and PX2 mounted in the short direction scan the respective short direction lines of PX1L and PX2L, and the dimensions a1 and b1 to both ends in the short direction. And dimensions a2 and b2. The center line CTS in the short direction of the steel slab can be drawn from the dimensions a1, b1 and dimensions a2, b2 and the distance e to which the sensors PX1, PX2 are attached. Further, the crane parallel line CTC and the steel slab short length The angle θ formed with the direction center line CTS, that is, the inclination angle θ of the billet slab viewed from the crane is calculated.

When measuring the edges in the long direction, measuring from the top as much as possible can measure the edges more accurately, so a wide area laser for detecting the long direction according to the long dimension of the slab to be handled. The distance sensors PY1 and PY2 are attached at reasonable positions, and a distance e between positions is set.
In this embodiment, the attachment positions of the wide-area laser distance sensors in the short direction and the long direction are installed on the same line with the same e dimension, but the e dimension in the short direction and the long direction are different. It may be a dimension position.
Note that the long direction detection wide area laser distance sensors PY1, PY2 are installed on the same line parallel to the crane parallel line CTC.
Long-range direction wide-area laser distance sensors PY1 and PY2 scan the PY1L or PY2L line, measure the d dimension and the c dimension, and calculate the longitudinal center on the PY1L and PY2L lines.

When the billet slab tilt angle θ is small as a result of measurement in the short direction or when the dimension f from the attachment position of the long direction wide range laser distance sensors PY1 and PY2 to the billet slab short direction center line CTS is small, the d dimension , C, and e are centered in the longitudinal direction.
When the f dimension is large and the θ angle is large, the correction dimension g dimension from the trigonometric function to the center in the longitudinal direction is calculated, and the correction g is added to obtain the center in the longitudinal direction.

  In addition, when the measured inclination angle θ of the billet slab is too large, when the billet slab SB is lifted by the crane CR, a large rotational force is generated, which is dangerous. Therefore, the inclination angle θ of the billet slab is too large. If it is larger, the automatic operation is stopped before raising the billet slab SB, and an abnormal alarm is issued.

The billet slabs SB are stacked non-aligned on the pallet PL as shown in FIG.
For this reason, when looking down from the crane CR with the wide-area laser distance sensor PS, that is, PX1, PX2, PY1, PY2, in addition to the edge of the uppermost slab slab SB, the slab slab loaded on the lower slab The edge of SB is also visible.
Since the steel slab slabs are gripped one by one stacked on the uppermost stage, it is necessary to measure only the edge of the uppermost steel slab slab SB.
At this time, the uppermost surface height TP of the steel slab slab SB is detected from the highest position object measured by the wide-area laser distance sensor PS on the pallet on which the steel slab slabs are stacked. For this reason, only the uppermost steel slab slab SB can be measured by not measuring from the position lower than the steel slab measurement threshold height dimension TKS from the upper surface height TP.
In addition, since the thickness dimension TK of the billet slab brought into the slab yard is determined, the billet slab measurement threshold height dimension TKS is smaller than the thickness dimension TK of the billet slab, and detection errors and In consideration of the shape error of the non-detected object, the entire upper surface of the upper steel slab slab can be detected, and the lower steel slab is appropriately set so as not to be detected.

Note that the wide-area laser distance sensor PS, that is, PX1, PX2, PY1, and PY2, must be attached to a position where the steel slab SB has good visibility, but the steel slab SB brought into the slab yard is in a high temperature state. Depressed, strong radiant heat is emitted. In order to protect the wide-area laser distance sensor PS from this strong radiant heat, it is housed in a heat insulating cover shown in FIG.
This heat-insulating cover covers the wide-area laser distance sensor PS with a heat-insulating heat-insulating cover containing a heat insulating material, and a laser irradiation viewing window PH is provided on the lower surface.
The viewing window PH is provided with a heat-shielding shutter SH for shielding radiant heat, and normally, radiant heat does not strike the wide-area laser distance sensor PS.
In addition, a hole for taking in cooling air is provided on the upper surface of the heat insulating cover box BX for shielding radiant heat, and the cooling ventilation FW is blown by the cooling fan FN so that the surface of the wide area laser distance sensor PS and the heat insulating cover box for radiant heat shielding. Cooling air is applied to the inner surface of the BX and the surfaces of the radiant heat shielding thermal shutter SH and the shutter driving actuator AC, and each part is cooled by blowing it out from the laser irradiation viewing window.
A fan cover CV is provided on the top of the cooling fan FN to prevent dust and rainwater from entering from the opening of the cooling fan.

  When performing measurement using the wide-area laser distance sensor PS, as shown in FIG. 5, the shutter driving actuator (rotary solenoid) AC is driven, the radiation heat shielding thermal shutter SH is opened, and the laser irradiation viewing window PH is transmitted. Like to do.

The radiant heat shielding thermal shutter SH is opened and closed according to the time chart shown in FIG.
First, when the measurement command CM of the wide-area laser distance sensor PS is issued, as shown in the chart of the thermal shutter operation for radiant heat shielding, the thermal shutter opening operation OP for radiant heat shielding is started, and the opening operation OP is started in about 0.2 seconds. Is completed. After that, a wide range laser distance sensor measurement MS is performed after a waiting time ST of about 0.3 seconds, the measurement is completed in about 0.05 seconds, and the measurement command CM is lowered after the completion of the measurement MS. Thus, the radiant heat shielding thermal shutter closing operation CL is completed in about 0.2 seconds.
This series of operations is performed instantaneously for about 0.75 seconds, thereby preventing the surface temperature of the wide-area laser distance sensor PS from rising due to the radiant heat generated by the billet slab.
Once the measurement command CM is issued, the re-measurement interval time IV is provided so that the re-measurement cannot be performed for a certain period of time, so that the thermal shutter for radiant heat shielding is repeatedly opened in a short time, so that the wide-area laser distance sensor PS To prevent the surface temperature of the material from rising.

  As described above, the billet slab gripping position detection method of the billet slab transport overhead crane of the present invention has been described by taking the billet slab yard billet overhead crane for handling the billet slab as an example. It is not limited to the structure described in the example, The structure can be changed suitably in the range which does not deviate from the meaning.

  The billet overhead crane of the present invention can meet the industrial issues of automation and safety because it can be automated by optimizing the billet overhead crane and by optimizing the gripping position of the manually operated crane. In addition to being able to be used suitably for the billet overhead crane for handling the billet slab in the billet slab yard, it can also be used for the purpose of the billet overhead crane for various billets, In addition, it can be applied without distinction between newly installed, existing, automatic, and manual.

CR Steel bill slab transport crane TG Steel bill slab grip grip SB Steel bill slab (steel)
PL slab storage pallet PX1 Wide range laser distance sensor 1 for short direction detection
PX2 Wide range laser distance sensor 2 for short direction detection
PY1 Wide range laser distance sensor 1 for long direction detection
PY2 Long range laser distance sensor 2 for long direction detection
PX1L Wide-area laser distance sensor for scanning in the short direction 1 PX2L Wide-area laser distance sensor for scanning in the short direction 2 scanning lines PY1L Wide-area laser distance sensor for scanning in the long direction 1 scanning line PY2L Wide-area laser distance sensor for scanning in the long direction 2 scanning lines a1 Left-side edge distance in the short direction 1 b1 Right-side edge distance in the short direction 1 a2 Short-edge direction 2 line left-side distance b2 Short-direction 2 line right-side edge distance c Long-length direction PY1-side edge distance d Long-length direction PY2 Side edge distance e PX1, PX2 or PY1, PY2 Longitudinal distance between mounting positions CTS Steel slab short direction center line CTC Crane parallel line θ Steel slab slab tilt angle f Steel strip slab short length from long direction detection sensor mounting position Dimension to the center line in the direction g Correction dimension to the center in the longitudinal direction C T Billet slab center (center of gravity detection)
PS Wide-area laser distance sensor SL Laser irradiation line TP Top surface slab slab top surface height TK Steel slab slab thickness dimension TKS Steel slab slab measurement threshold dimension BX Radiation heat shielding cover box (with heat insulation)
PH Laser irradiation viewing window SH Thermal shutter for radiant heat shielding AC Shutter drive actuator (rotary solenoid)
FN Cooling fan CV Fan cover FW Cooling ventilation CM Measurement command SD Radiation heat shielding thermal shutter operation MS Wide area laser distance sensor measurement OP Radiation heat shielding thermal shutter opening operation ST Wait time CL Radiation heat shielding thermal shutter closing operation IV Remeasurement interval time

Claims (4)

  Equipped with a plurality of wide area laser distance sensors for measuring the size of steel slabs on the crane of an overhead crane for conveying slabs, moving the crane to the upper surface of the place where the steel slabs are to be handled Is a billet overhead crane for measuring the size of a billet slab by measuring the length of both ends of the two lines in the short direction of two lines with two wide range laser distance sensors in the short direction of the billet The center of the steel slab in the short direction and the slope of the steel slab are calculated with respect to the crane parallel line. For the long direction, near the upper side of the long side of the steel slab and the long side opposite to it. Wide range laser distance sensors for detecting the long direction are provided on two cranes near the upper side of the short direction of the direction, and these two long direction distance sensors should be placed on the same line of the crane's parallel lines. From the position dimension of each long direction edge detected by the wide range laser distance sensor for long direction detection, the center dimension in the long direction is calculated, and the center position in the short direction and the center position in the long direction are calculated as steel. Equipped with a series of systems that judge the position of the center of gravity of the piece and move the billet-carrying overhead crane so that the center position of the billet-carrying tongue is aligned with the center position of the billet and grip the billet An overhead crane for transporting billets.   When the short plane direction distance between the short direction center line of the billet and the wide range laser distance sensor mounting position for detecting the long direction is large and the billet has a large inclination angle with respect to the crane parallel line, the short direction of the billet The long distance detected by the wide-area laser distance sensor for detecting the long direction, based on the trigonometric function of the plane distance between the center line and the wide-area laser distance sensor for detecting the long-direction direction and the inclination angle of the steel slab with respect to the parallel line of the crane. 2. A correction method for correcting the direction center position and a method for processing the inclination angle of a billet that issues an alarm when the billet has an excessively large inclination angle with respect to the parallel line of the crane. The overhead crane for billet conveyance described in 1.   When measuring stacked slabs from the upper crane with a wide-area laser distance sensor, do not measure from the top slab height below the dimension below the thickness of the slab being measured. The overhead crane for billet transfer according to claim 1 or 2, wherein only the uppermost billet is measured.   A billet transport overhead crane equipped with a wide-area laser distance sensor for measuring billets attached to an overhead crane, which is mounted in a form of looking down on a steel piece placed on the ground from above the crane. Covered with a heat insulating cover provided with a cooling device, the heat insulating cover is provided with a laser irradiation peephole for a wide range laser distance sensor, the peep hole is provided with a heat insulating shutter, The thermal shutter is opened only at the instant when the wide-area laser distance sensor performs measurement, and laser light can be transmitted through the peephole. The thermal shutter is closed at all times. Once the shutter is opened, a certain time has not elapsed. And the billet overhead crane for preventing the shutter from opening.

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