JP2016176909A - Method for reading stamp of steel material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stamp reading method which enables a stamp formed on a surface of a steel material to be read stably while little affected by color, light, and shadow on the surface of a stamped steel material.SOLUTION: The method for reading a stamp formed on a surface of a steel material SS, using a stamp measuring device 4 is provided that includes: a distance adjustment step of positioning the stamp measuring device 4 at such a position that a clearance between the stamp measuring device 4 and a surface SF on which the stamp is formed is within a range of a measurable clearance predetermined for the stamp measuring device 4; a distance measuring step of scanning the stamp-formed surface SF by the stamp measuring device 4 located within the measurable clearance range and measuring distribution of distances; and a reading step of reading a two-dimensional image of the stamp-formed surface SF from the measured distance distribution. The stamp measuring device 4 is comprised of a laser range finder.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method and a reading device for reading a display stamped on the surface of a steel material.

  A rolling method is widely known as a method for manufacturing steel bars. In this manufacturing method, the billet obtained through steps such as refining, ingot making, and ingot rolling is heated by a heating furnace. Next, this billet is subjected to multi-stage hot rolling. By this hot rolling, the billet is gradually reduced in diameter and lengthened. In this way, a base material is obtained. After this base material is cooled, it is cut into a predetermined size to obtain a steel bar. A large number (several to tens of bars) of steel bars are bound with a band and shipped.

  Regarding the manufacturing process of this steel bar, it is required to improve the traceability (traceability) of the history of steelmaking, heating, rolling, cutting, inspection and the like. For this purpose, each billet is given a unique identification for tracking billet information. This display is generally made by engraving. Then, the billet marking display is read at a predetermined time in the manufacturing process of the steel bar. For example, before charging into the heating furnace. And billet information is added to rolling tracking.

  This marking display is formed by partially denting the surface of the steel material. Such recesses on the surface of the steel material can be detected by various methods. For example, it can be confirmed visually. However, in the case of visual observation, there is a possibility that misrecognition occurs, and the work load is large.

  Japanese Laid-Open Patent Publication No. 5-28311 discloses a method of reading a product display character stamped on a steel product with a camera. However, in the case of imaging using a camera, colors such as paint and rust attached to the surface of the imaging target may adversely affect the binarization processing of the image. As a result, there is a risk of reading failure (misreading). In order to avoid these problems, it is possible to devise a lighting method or to create halation by a flash at the time of photographing. However, if these lights are irradiated to the bottom of the marking, there is a possibility that the letter of the marking cannot be captured as an image.

Japanese Patent Laid-Open No. 5-28311

  The present invention has been made in view of the above-described present situation. An object of the present invention is to provide a method and an apparatus capable of stably reading a stamped character with little influence of the color, light, and shadow of the surface of the steel material on which the stamp is formed when the stamp is read.

The steel material stamp reading method according to the present invention is a method of reading a mark formed on the surface of a steel material by a marking measuring instrument,
A distance adjusting step of positioning the marking measuring instrument at a position where the separation distance between the marking measuring instrument and the surface on which the marking is formed is within the range of the measurable separation distance defined in the marking measuring instrument;
A distance measuring step of measuring the distribution of distances by scanning the marking forming surface with the marking measuring device within the measurable separation distance;
A reading step for obtaining a two-dimensional image of the engraving surface from the measured distance distribution;
Contains
The marking measuring instrument is composed of a laser distance meter.

Preferably, prior to the distance adjustment step, a preliminary measurement step of measuring a separation distance between the laser distance meter and the marking forming surface is included,
In the distance adjustment step, when the separation distance measured in the preliminary measurement step is out of the measurable separation distance range, the laser distance meter is separated or brought close to the marking forming surface. And within the range of the measurable separation distance.

Preferably, a plurality of steel materials to be measured are arranged and arranged,
In the distance adjusting step and the distance measuring step, the laser rangefinder scans the marking forming surface of each steel material while moving in the steel material arrangement direction.

Preferably, in the preliminary measurement step, a distance between the laser distance meter and each marking forming surface of the plurality of steel materials is measured by a second distance meter,
In the distance adjusting step, the laser distance meter is separated from or approached to the marking forming surface so that the separation distance is the same for all steel materials.

The steel marking reading device according to the present invention is a device for reading the marking formed on the surface of the steel material,
A laser distance meter that measures the distribution of the separation distance to the surface on which the inscription is formed;
A first moving device for moving the laser distance meter along the marking forming surface of the steel material;
A second moving device for moving the laser distance meter away from and approaching the marking forming surface;
A control device for controlling the operation of the first moving device and the second moving device,
This controller is
By operating the first moving device, the laser distance meter is scanned over the marking forming surface, and a two-dimensional image of the marking forming surface is obtained from the distribution of the measured separation distance.

Preferably, it comprises a second distance meter for measuring the distance between the laser distance meter and the marking forming surface,
The control device is
Before scanning the marking surface with the laser distance meter,
When the separation distance measured by the second distance meter is out of the measurable separation distance range defined for the laser distance meter, the separation distance is within the measurable separation distance range. Then, the second moving device is operated.

  According to the present invention, when reading the marking on the surface of the steel material, the influence of the color, light, and shadow on the surface of the steel material on which the marking has been made is small, and stable reading is possible.

FIG. 1 is a plan view showing an outline of a mechanism portion of a steel marking reading device according to an embodiment of the present invention. FIG. 2 is a front view of the mechanism section viewed along line II-II in FIG. 3A is a perspective view showing the positional relationship between the laser distance meter and the marking forming surface of the steel material in the marking reading device of FIG. 1, and FIG. 3B is the laser distance of FIG. 3A. It is a figure explaining the relationship between the measurement range of a meter, a near field, and a far field. FIG. 4A is a diagram showing the separation distance between a plurality of arrayed steel materials to be read and the laser distance meter, and FIG. 4B illustrates the measurement range of the laser distance meter at this separation distance. It is a figure to do. FIG. 5 is a block diagram showing an outline of a mechanism unit and a control device of the marking reading device according to the embodiment of the present invention.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  1 and 2 show a marking reading device (hereinafter, also simply referred to as a reading device) 2. FIG. 1 is a plan view of the reading device 2, and FIG. 2 is a front view. The reading device 2 can measure steel materials SS of various shapes such as round bars, square bars, steel pieces, and the like. Here, a round steel bar is exemplified as the steel material SS to be engraved reading.

  The reading device 2 includes a laser distance meter 4, a moving mechanism 6 for moving the laser distance meter 4, a second distance meter 8, and a control device 10 shown in FIG. The laser distance meter 4, the moving mechanism 6, and the second distance meter 8 can be called the mechanism unit 30 in the reading device 2. The control device 10 controls the mechanism unit 30. The mechanism unit 30 is installed on the gantry 31.

  In FIG. 1 and FIG. 2, three axial directions of XYZ are shown in order to clarify the positional relationship between the reading device 2 and the steel material SS to be measured. The direction in which the laser distance meter 4 is separated from and approaching the surface (hereinafter also referred to as a marking forming surface) SF of the steel material SS (longitudinal direction of the steel material) is the Z-axis direction, and the arrangement direction (conveying direction) of the steel material SS is the Y-axis. The direction perpendicular to each of the Z axis and the Y axis is the X axis direction. In the present embodiment, both the Y axis and the Z axis extend in the horizontal direction, and the X axis direction extends in the vertical direction.

  In the reading device 2, the laser distance meter 4 measures the distance in the Z-axis direction to the marking forming surface SF that is the measurement target surface. The stamp is formed on the end surface of the steel bar SS. The distance distribution is measured for a predetermined range of the marking portion (concave portion) and the non-marking portion (flat portion) on the marking forming surface SF. This predetermined range is a measurement width W in the X-axis direction shown in FIG. The distance from the laser distance meter 4 to the stamped portion is different from the distance from the laser distance meter 4 to the non-marked portion. From the measured distribution of distances, a stamped display is read. There are few adverse effects due to shadows, rust, paint, etc., as in the case of conventional scanning by camera photography.

  The laser distance meter 4 needs to scan (scan) in the Y-axis direction along the marking forming surface SF in order to read the marking on the marking forming surface SF. For this reason, the said moving mechanism 6 moves the laser distance meter 4 along the marking formation surface SF of steel material SS of a stationary state. The measured distance distribution is converted into a two-dimensional image by a computer program in the control device 10 to be described later. This is a reading step. The moving mechanism 6 is configured as follows.

  The moving mechanism 6 is fixed to the first linear guide 12 as a first moving device extending in the Y-axis direction, the first slider 14 movably mounted on the first linear guide 12, and the first slider 14. In addition, a second linear guide 16 as a second moving device extending in the Z-axis direction, a second slider 18 movably mounted on the second linear guide 16, and projecting on the second slider 18. In addition, a ball screw mechanism 20 extending in the X-axis direction (vertical direction) is provided. A laser distance meter 4 is attached to the ball screw mechanism 20.

  The linear guide is a linear motion guide, and is a mechanism for moving a mounted slider linearly. The first linear guide 12 includes a Y-axis drive servomotor 22. The second linear guide 16 includes a Z-axis drive servo motor 24. Instead of this linear guide, a ball screw mechanism (feed screw mechanism) or the like may be employed. In the present embodiment, the ball screw mechanism 20 has a simple structure in which the handle 26 is manually rotated to rotate the ball screw 28.

  The first slider 14, the second linear guide 16, the second slider 18, the ball screw mechanism 20, and the laser distance meter 4 are integrally movable with the first linear guide 12 in the Y-axis direction. The second slider 18, the ball screw mechanism 20, and the laser distance meter 4 are integrated and can be moved in the Z-axis direction by the second linear guide 16. The laser distance meter 4 can be moved alone in the X-axis direction (vertical direction) by the ball screw mechanism 20. The ball screw mechanism 20 is used for alignment of the laser distance meter 4 with respect to the steel material SS in the X-axis direction. The laser distance meter 4 is configured to be movable in three XYZ directions by a moving mechanism 6.

  In this reading device 2, the laser rangefinder 4 is capable of a stroke of 500 mm in the Z-axis direction, a stroke of 1200 mm in the Y-axis direction, and a stroke of 100 mm in the X-axis direction. However, it is not limited to these strokes. These strokes are determined according to the outer diameter of the steel material SS, the specifications of a laser distance meter 4 described later, and the like.

  In the present embodiment, an ultrasonic distance meter is employed as the second distance meter 8 described above. However, it is not limited to an ultrasonic distance meter. The second distance meter 8 measures a separation distance L (see FIG. 3A) between the marking forming surface SF of one or more steel materials SS and the reference portion of the laser distance meter 4. The measured separation distance L of each marking forming surface SF is stored in the control device 10 in association with each steel material SS. This measurement is a preliminary measurement for quantitatively grasping the position of the steel material SS. That is, this measurement is a preliminary measurement step for guiding the laser distance meter 4 within a separation distance range in which the marking forming surface SF can be measured. For this measurement, the reference site of the second distance meter 8 is preferably set at the same position on the Z axis as the reference site of the laser distance meter 4. This reference portion is a portion of the laser distance meter 4 that is determined in order to specify the separation distance L between the laser distance meter 4 and the marking forming surface SF. In this embodiment, this reference | standard site | part is made into the front-end | tip position of the measurement object (steel material) side of the laser distance meter 4. Of course, it is not limited to this part.

  In the present embodiment, the second rangefinder 8 is separate from the laser rangefinder 4 and is fixed to the gantry 31 so as not to move. As shown in FIGS. 1 and 2, the position of the second distance meter 8 in the Y-axis direction is a position upstream of the laser distance meter 4 in the conveying direction of the steel material SS. Furthermore, it is a position on the upstream side of the last one of a plurality (5 in the present embodiment) of steel materials SS that are simultaneously conveyed and stationary. According to this arrangement, when all the steel materials SS that have been transported are stationary, the separation distance L of the marking forming surface SF of all the steel materials SS has been measured. By this second distance meter 8, the separation distance L of the marking formation surface SF of all the steel materials SS is grasped in the arrangement order of the steel materials SS.

  The second rangefinder 8 is not limited to the above arrangement. For example, the second distance meter 8 may be movable integrally with the laser distance meter 4 in the arrangement direction (Y-axis direction) of the steel materials SS. For this purpose, the second distance meter 8 may be fixed to the first slider 14.

  According to this reading device 2, distance measurement with a plurality of steel materials SS as one batch is also possible. In general, a plurality of steel materials SS are arranged in a horizontal state on a pallet and conveyed, and are in a horizontal state even when stopped. This pallet is generally in the form of a general chain conveyor in which a plurality of V-shaped grooves are formed in parallel. The steel bar is placed in a stable state in this V-shaped groove. Therefore, the plurality of steel bars can be in a state in which the positional relationship is fixed.

  According to this reading device 2, in the existing steel material production line, in a time cycle (for example, 35 seconds stop) in which the conveyance of the steel material SS is stopped, the markings of a plurality of stopped steel materials SS are read in one scan. Can do. In this case, the laser distance meter 4 scans in the Y-axis direction over a plurality of steel materials SS. Also in the scanning with respect to the plurality of steel materials SS, the moving mechanism 6 moves the laser distance meter 4. However, as shown in FIG. 1, the plurality of steel materials SS when stopped in the middle of the conveyance are usually not flush with each other. The separation distance L from the marking formation surface SF to the laser distance meter 4 is often different depending on the steel material SS.

  As shown in FIG. 1, here, 300 mm is exemplified as the maximum width of the variation in the position in the Z-axis direction of the marking forming surface SF. This variation is measured by the second distance meter 8 and is stored in the control device 10. The center position of the variation is referred to as a reference position (hereinafter referred to as a stamp formation surface reference position) CP of the stamp formation surface SF. A position 300 mm away from the marking formation surface reference position CP is referred to as a reference position (hereinafter simply referred to as a distance meter reference position) SP of the laser distance meter 4. The laser distance meter 4 is configured to be able to retreat to a retreat position BP that is separated rearward by 350 mm from the distance meter reference position SP. As described above, the stroke of the laser distance meter 4 in the Z-axis direction is 500 mm. Therefore, the laser distance meter 4 can approach the marking forming surface SF by 150 mm from the distance meter reference position SP. The separation distance between the marking forming surface reference position CP and the distance meter reference position SP and the retreat distance are determined according to the specifications of the laser distance meter 4 and the like.

  The distance meter reference position SP is generally set as a position from the formation surface reference position CP so that the measurement width W is a separation distance L that can cover the marking area of the marking formation surface SF. The retreat distance of 350 mm is set as a position for retreating in the Z-axis direction so that a person does not touch the steel during maintenance.

  The laser distance meter 4 has a measurable separation distance L range (also called a measurable separation distance range). As shown in FIG. 3 (b), the measurable separation distance L is within a longer distance (far distance) L2 from a position away from the laser distance meter 4 by a predetermined distance (short distance) L1. This is the range up to the separated position. That is, the measurable separation distance range of the laser distance meter 4 is not less than L1 and not more than L2. The short distance L1 is also called clearance. The marking forming surface SF at a position outside the measurable separation distance range may not be measurable. The size of the measurable range is L2-L1. This distance range is also called the measurement range or full scale. This measurement range MR is set as a specification of the laser distance meter. The specifications of these laser distance meters are stored in the control device 10.

  Table 1 and FIG. 3 show an example of the measurement range MR, the resolution of the laser distance meter 4, and the measurement width W. The clearance (short distance) L1 of the laser rangefinder 4 exemplified here is 135 mm, and the long distance L2 is 355 mm. Therefore, the measurable separation distance range is 135 mm or more and 355 mm or less, and the measurement range (L2-L1) MR is 220 mm. However, the specifications of the laser distance meter are not limited to these values. It can be changed according to the size of the steel material to be measured. Here, the diameter of the cross section of the steel material SS to be measured, that is, the diameter of the marking forming surface SF is 167 mm. A laser distance meter 4 having a specification suitable for the steel material SS of this size is employed.

  In general, the shorter the separation distance L, the better the resolution, but the measurement width (X-axis direction width) W becomes smaller. Conversely, the longer the separation distance L, the lower the resolution, but the measurement width W increases. Therefore, the user selects a laser distance meter that satisfies each specification in consideration of the width of the marking region of the steel material SS, the variation in the Z-axis direction position of the marking forming surface SF, the resolution necessary for reading, and the like. The clearance L1 and the measurement range MR are uniquely determined by the specifications of the laser distance meter.

  The measurement width W1 in the X-axis direction at the position of the short distance L1 is 64 mm. The measurement width W1 at the position of the short distance L1 is also referred to as a near field. The X-axis direction resolution at the position of the short distance L1 is 0.079 mm / dot, and the Z-axis direction resolution is 0.010 mm / dot. On the other hand, the measurement width W2 in the X-axis direction at the position of the long distance L2 (= 355 mm) is 162 mm. The measurement width W2 at the position of the far distance L2 is also referred to as a far field. The X-axis direction resolution at the position of this long distance L2 is 0.181 mm / dot, and the Z-axis direction resolution is 0.052 mm / dot. The smaller the resolution value, the better the resolution.

  The above-described measurable separation range is not limited as much as the focal length of the optical camera. That is, according to the laser distance meter 4, clear measurement is possible over a wide range of distances.

  However, when the width of the variation of the marking forming surface SF exceeds the measurement range MR, there is a marking forming surface SF that is not measured when scanning in a straight line in the Y-axis direction. In this case, it is necessary to scan the laser distance meter 4 while moving the laser distance meter 4 away from the marking formation surface SF so that the separation distances of all the marking formation surfaces SF are within the measurable separation distance range. The step of moving the laser distance meter 4 back and forth in the Z-axis direction so as to be separated and approached to the marking forming surface SF is a distance adjustment step. The variation of the marking forming surface SF and the measurement range MR are both stored in the control device 10. The control device 10 determines whether the laser distance meter 4 needs to move in the Z-axis direction and instructs the moving device 6 to move in the Z-axis direction.

  Even if the separation distance L is within the measurable separation distance range, the resolution of the laser rangefinder 4 varies depending on the length of the separation distance L. As a result, if the separation distance L is different, the measurement accuracy may be different. Therefore, if the laser rangefinder 4 scans a plurality of steel materials SS with different separation distances L in a straight line in the Y-axis direction, the accuracy of the two-dimensional image of the marking display obtained from the measurement data is also improved. It can be different depending on the SS.

  When the variation width of the position of the marking formation surface SF is within the measurement range MR, the laser distance meter 4 only moves to a position where the marking formation surfaces SF of all the steel materials SS are within the measurement range MR. It's okay. Thereafter, the laser distance meter 4 may scan in a straight line without approaching the marking forming surface SF. That is, the laser distance meter 4 needs to be separated from and approaching the marking forming surface SF at most once. However, this is conditional on the fact that the above-described non-uniformity in image accuracy can be tolerated and that the marking areas of all the marking forming surfaces SF are covered by the measurement width W.

  On the other hand, in order to measure the marking of all the steel materials SS with the same accuracy, the laser distance meter 4 needs to scan while placing the same separation distance L with respect to all the steel materials SS. For this purpose, the laser distance meter 4 needs to scan while being spaced apart and approaching corresponding to the Z-axis position of each marking forming surface SF. In this case, it is preferable that the same separation distance L is a distance at which the width in the X-axis direction of the marking region of the steel material SS is equal to the measurement width W. The control device 10 instructs the moving mechanism 6 to move in the Z-axis direction according to the position of each marking forming surface SF.

  FIG. 4 illustrates the separation distance L of the laser rangefinder 4 with respect to the five steel materials SS and the measurement width W at this separation distance. However, FIG. 4 is a diagram showing the Y-axis direction and the Z-axis direction, and the measurement width W is the X-axis direction (vertical direction) not shown, but for the sake of easy understanding, it is projected and shown in the Y-axis direction. ing. Each position of the steel material SS is the same as each position of the steel material SS shown in FIG. Identification codes from SS1 to SS5 are appended to the five steel materials in order. SS1 is attached to the steel material at the top of the conveyance, and SS5 is attached to the steel material at the back. The variation of the marking forming surface SF of the five steel materials SS is 300 mm. The third steel material SS3 and the fifth steel material SS5 are both at the position of the stamp forming surface reference position CP-150 mm, and only the fourth steel material SS4 is at the position of the stamp forming surface reference position CP + 150 mm. The first steel material SS1 is at the position of the marking formation surface reference position CP-40 mm. The second steel material SS2 is located at the stamp forming surface reference position CP-10 mm. The separation distance L is 260 mm for the steel material SS1, 290 mm for the steel material SS2, and 150 mm for the steel materials SS3 and SS5. In the steel material SS4, the laser distance meter 4 has moved 110 mm from the distance meter reference position SP in a direction approaching the steel material SS4, so the separation distance L is 340 mm. The variation of the marking forming surface SF is 300 mm, which exceeds the measurement range MR of the laser distance meter 4 of 220 mm. Therefore, the laser distance meter 4 needs to move in the Z-axis direction in order to read the markings of all the steel materials SS1-SS5.

  In FIG. 4, the laser distance meter 4 is stationary at the distance meter reference position SP with respect to the four steel materials SS1-SS3, SS5. The laser distance meter 4 moves only with respect to the fourth steel material SS4. As described above, the laser distance meter 4 moves 110 mm from the distance meter reference position SP in a direction approaching the steel material SS4. After measuring the distance, it returns to the original distance meter reference position SP.

  FIG. 4B shows a measurement width W corresponding to the separation distance shown in FIG. 4A and concentric circles having the measurement width W as a diameter. This concentric circle indicates a range that can be measured by the laser distance meter 4. Therefore, the inscription needs to be formed in this concentric circle. There is a possibility that the part of the inscription formed at the site exceeding this range cannot be read. The measurement width W is 119 mm for the steel material SS1, 133 mm for the steel material SS2, 70 mm for the steel materials SS3 and SS5, and 155 mm for the steel material SS4. In this case, the minimum measurement width W is 70 mm. It is necessary to form an inscription in a narrow concentric circle having a diameter of 70 mm on the end surface of the steel material SS having an outer diameter of 167 mm. In order to relax such a restriction on the marking area, a minimum measurement width may be set in advance. For example, the diameter of the circle indicating the maximum marking range is set to 110 mm. In this case, in the steel materials SS3 and SS5, the distance L is set back from the distance meter reference position SP so that the distance L is 239 mm or more and 355 mm or less. That is, it moves backward within the range of 89 mm or more and 205 mm or less from the distance meter reference position SP. The above is an example of the displacement of the laser distance meter 4. In the case of the above-described method in which the distance in the X-axis direction of the stamped region of the steel material SS is equal to the measurement width W, the separation distance L is 239 mm, that is, 89 mm from the distance meter reference position SP so as to improve the resolution. It is preferable to retreat.

  As shown in FIG. 5, the control device 10 includes a controller (referred to as a first controller) 32 for the laser distance meter 4, a servo driver (referred to as a Y-axis servo driver) 34 for the Y-axis drive servomotor 22, and a Z-axis drive. A servo driver (referred to as a Z-axis servo driver) 36 for the servo motor 24, a controller (referred to as a second controller) 38, a personal computer (also referred to as PC) 40, and a programmable logic controller (also referred to as PLC) 42 for the second distance meter 8 I have. Instead of the drive servo motor, a drive motor and an inverter driver may be used in combination.

  The first controller 32 has a function of converting the distribution of the distance of the measurement width W in the X-axis direction on the marking forming surface. Depending on the specifications of the laser rangefinder, there are also functions that combine a function of generating a distribution of distance scanned in the Y-axis direction as a two-dimensional image and a function of recognizing characters from the generated two-dimensional image. The information obtained by the first controller 32 is transmitted to the PC 40 by means of communication or the like, but the function to generate the two-dimensional image and the function to recognize characters are shared by either the laser distance meter or the PC 40. Designed as such. The second controller 38 calculates the position of the marking forming surface SF of the steel material SS from the measurement value obtained by the second distance meter 8, and transmits this to the PLC 42.

  The Y-axis servo driver 34 rotates the Y-axis drive servomotor 22 by a predetermined number of rotations based on the data specifying the Y-axis direction position of each steel material SS transmitted from the PLC 42. Thereby, the laser distance meter 4 moves on the first linear guide 12 to a position corresponding to the designated steel material SS.

  The Z-axis servo driver 36 rotates the Z-axis drive servo motor 24 by a predetermined number of rotations based on data specifying the Z-axis direction position of the marking forming surface SF of each steel material SS transmitted from the PLC 42 as necessary. . Thereby, the laser distance meter 4 moves on the second linear guide 16 to a designated position on the Z axis.

  The PC 40 uniquely identifies the steel material SS from the distance distribution obtained from the first controller 32, the information regarding the two-dimensional image or character recognition, the position information of the steel material SS obtained from the PLC 42, and the position information of the moving mechanism 6. It has a function of reading a mark as a display, storing it as billet information, and adding billet information to rolling tracking. The PLC 42 instructs the servo drivers 34 and 36 to scan in the Y-axis direction and advance and retreat in the Z-axis direction, and recognizes the position information of the sliders 14 and 18. Further, the position of the marking forming surface of the steel material SS obtained from the second controller 38 is calculated. The position information of the steel material SS and the position information of the moving mechanism 6 are transmitted to the PC 40 by means such as communication.

  The steel material stamp reading method described above is useful for tracking the manufacturing process history of a steel material.

2 ... Reading device 4 ... Laser distance meter 6 ... Movement mechanism 8 ... Second distance meter 10 ... Control device 12 ... First linear guide 14 ... First slider 16 .... Second linear guide 18 ... Second slider 20 ... Ball screw mechanism 22 ... Z-axis drive servo motor 24 ... Y-axis drive servo motor 26 ... Handle 28 ... Ball screw 30 ... Mechanical part 31 ... Stand base 32 ... First controller 34 ... Z-axis servo driver 36 ... Y-axis servo driver 38 ... Second controller 40 ... PC (PC)
42 ... Programmable logic controller (PLC)
BP: Retraction position CP: Stamp forming surface reference position L ... Separation distance MR ... Measurement range SF ... Stamp forming surface SP ... Distance meter reference position SS ... Steel material W ...・ Measurement width

Claims (6)

A method of reading a stamp formed on the surface of a steel material with a stamp measuring instrument,
A distance adjusting step of positioning the marking measuring instrument at a position where the separation distance between the marking measuring instrument and the surface on which the marking is formed is within the range of the measurable separation distance defined in the marking measuring instrument;
A distance measuring step of measuring the distribution of distances by scanning the marking forming surface with the marking measuring device within the measurable separation distance;
A reading step for obtaining a two-dimensional image of the engraving surface from the measured distance distribution;
Contains
A method for reading a marking on a steel material, wherein the marking measuring instrument comprises a laser distance meter. Before the distance adjustment step, including a preliminary measurement step of measuring a separation distance between the laser distance meter and the marking forming surface;
In the distance adjustment step, when the separation distance measured in the preliminary measurement step is out of the measurable separation distance range, the laser distance meter is separated or brought close to the marking forming surface. The method for reading a stamp of a steel material according to claim 1, wherein the marking is positioned within a measurable separation distance. The steel materials to be measured are plural and arranged.
3. The steel material marking reading method according to claim 1, wherein, in the distance adjusting step and the distance measuring step, the laser distance meter scans a marking forming surface of each steel material while moving in the arrangement direction of the steel materials. In the preliminary measurement step, the second distance meter measures the separation distance between the laser distance meter and each marking forming surface of the plurality of steel materials,
The steel material marking reading method according to claim 3, wherein in the distance adjusting step, a laser distance meter is separated or approached to the marking forming surface so that the separation distance is the same for all steel materials. A device for reading a stamp formed on the surface of a steel material,
A laser distance meter that measures the distribution of the separation distance to the surface on which the inscription is formed;
A first moving device for moving the laser distance meter along the marking forming surface of the steel material;
A second moving device for moving the laser distance meter away from and approaching the marking forming surface;
A control device for controlling the operation of the first moving device and the second moving device,
This controller is
A steel material marking reading device that operates the first moving device to cause the laser distance meter to scan the marking forming surface and obtain a two-dimensional image of the marking forming surface from a distribution of measured separation distances. A second distance meter for measuring the distance between the laser distance meter and the marking forming surface;
The control device is
Before scanning the marking surface with the laser distance meter,
When the separation distance measured by the second distance meter is out of the measurable separation distance range defined for the laser distance meter, the separation distance is within the measurable separation distance range. 6. The steel marking reading device according to claim 5, wherein the second moving device is operated.

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