JP2009196035A - Grinder and grinding control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a grinding wheel from falling even when the measured value of the profile of a cast piece is different from the actual position of the cast piece. <P>SOLUTION: This grinder comprises: a grinding wheel 32 for grinding the surface of the cast piece; a measuring device for measuring the profile of the cast piece; a grinding wheel pressing device 36 for pressing the grinding wheel 32 against the surface of the cast piece; a pressing position detection device 37 for detecting the height of the pressing position of the grinding wheel 32; a moving means for moving the grinding wheel 32 on the surface of the cast piece; and a control part 70 for storing the height of the pressing position of the grinding wheel 32 within a predetermined distance from the end of the measured profile, determining whether the difference between the average of the heights of the stored pressing positions and the actual height of the pressing position of the grinding wheel 32 is equal to or larger than a threshold, and when the difference is equal to or larger than the threshold, and so controlling the grinding wheel 32 to as lower the pressing pressure of the grinding wheel. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present application relates to a grinding apparatus and a grinding control method, and more particularly, to a grinding apparatus and a grinding control method for preventing a grinding stone from dropping.

  In recent years, grinding machines that grind the surface of cast slabs (which are cuboidal steel products obtained by cutting continuously cast steel to a certain length) in the steelmaking process are damaged by grinding stones falling from the slab surface. It is required to improve the processing speed of the grinding process by reducing the delay due to the accident and the recovery process.

  One of the causes of such whetstone dropping may be the low accuracy of the slab contour measurement. For this reason, as a technique related to prevention of grinding wheel fall, there is a technique for accurately grasping the shape of a cast piece and further using a servo motor or the like having high positioning accuracy to prevent grinding stone fall. However, since the measurement timing of the slab contour is limited to once before grinding, if the slab swings before grinding or during grinding, the position of the slab after swinging cannot be detected. . In such a case, a difference occurs between the measurement position and the actual slab position, and the grinding stone falls.

  In view of the above-described problems, a grinding apparatus and a control method for reducing the falling accident of the grinding wheel by determining the position of the slab end during grinding of the slab surface without depending on only the profile measurement value of the slab Is required.

  In order to solve the above problems, a grinding wheel for grinding the surface of the slab, a measuring device for measuring the contour of the slab, a grindstone pressing device for pressing the grinding wheel against the surface of the slab, and a crimping position of the grinding wheel The position of the crimping position of the grinding wheel, the moving means for moving the grinding wheel on the surface of the slab, and the height of the crimping position of the grinding wheel within a predetermined distance from the end of the measured contour Determine whether the difference between the stored average height of the crimping position and the actual crimping position height of the grinding wheel is greater than or equal to a threshold value, and if the difference is greater than or equal to the threshold value, There is provided a grinding device having a control unit that controls the lowering.

  Furthermore, in order to solve the above-mentioned problem, a grinding control method using a grinding apparatus for grinding the surface of a slab, the contour of the slab is measured, the grinding wheel is pressure-bonded to the surface of the slab, and the grinding wheel Is moved on the surface of the slab, the height of the crimping position of the grinding wheel is detected, the height of the crimping position of the grinding wheel is stored within a predetermined distance from the edge of the measured contour, and the height of the stored crimping position is stored. Grinding control that determines whether or not the difference between the average height and the height of the actual crimping position of the grinding wheel is greater than or equal to a threshold value, and if the difference is greater than or equal to the threshold value, control is performed to lower the pressure of the grinding wheel A method is provided.

  When the difference is less than the threshold value, the pressing pressure of the grinding wheel may be maintained, and the determination may be made within a predetermined distance from the end of the measured contour.

  This grinding apparatus or grinding control method can determine the position of the end portion of the slab from the fluctuation of the height of the grinding wheel, thereby preventing the grinding stone from falling and preventing the grinding process from being delayed due to the grinding stone falling.

  In addition, when this grinding device or grinding control method determines that it is the end of the slab, the grinding pressure is reduced to zero and the slab grinding process is continued without interrupting the grinding process. Can be prevented.

Hereinafter, an embodiment of a grinding apparatus of the present application will be described with reference to the drawings.
FIG. 1 is a plan view showing an outline of the grinding apparatus 10. An example of the grinding apparatus 10 will be described with reference to FIG. In the following, the left-right direction in FIG. 1 is referred to as the X-axis direction, the up-down direction in FIG. 1 is referred to as the Y-axis direction, and the direction orthogonal to the plane of FIG.

The grinding device 10 is disposed on the two conveyors 12 and 14 that convey the slab S. When the surface of the slab S is ground by the grinding device, the slab S is conveyed from the right side to the left side in FIG.
The grinding apparatus 10 is connected to the grinding wheel 32, the support 34, the grinding wheel rotating motor 35, the first and second laser distance meters 42 and 43, and the support 34 to move the grinding wheel 32 in the Y-axis direction. And a carriage 20 for loading the carriage 30 and moving the grinding wheel 32 in the X-axis direction, and a control device 70 (see FIG. 2).

The two slabs S are conveyed from the right side to the left side in FIG. The carriage 20 moves the grinding wheel 32 in the X-axis direction by moving the wheels on the two X-axis rails 16 and 18 with wheels. The carriage 30 moves the grinding wheel 32 in the X-axis direction by moving on the Y-axis rails 53 and 54 on the carriage 20.
First and second laser distance meters 42 and 43 for measuring the distance from the side surface of the slab S are attached to the carriage 30. The first and second laser distance meters 42 and 43 are used for measuring the distance from the side surface of the slab S while moving the carriage 20 in the X-axis direction, as will be described later.

FIG. 2 is a side view showing the outline of the grinding apparatus 10 from the left side of the X axis.
The carriage 20 is driven by an X-axis servomotor 25 which is a servomotor shown in FIG. The amount of movement of the carriage 20 is detected by the X-axis encoder 26. The X-axis encoder 26 has a gear, and the amount of movement of the carriage 20 is measured when the gear meshes with a rack provided in parallel with the X-axis rail 16. The movement amount data measured by the X-axis encoder 26 is transmitted to the control device 70. The carriage 30 moves in the Y-axis direction using the wheels 55 and 56 on the Y-axis rails 53 and 54 on the rail beams 51 and 52 supported by the support columns 57 and 58. Since the operation accuracy of the grinding wheel 32 on the X axis is less required than the operation accuracy on the Y axis, the X axis motor may be an inverter control motor.

FIG. 3 is a side view showing the outline of the grinding apparatus 10 from the lower side of the Y-axis.
The carriage 30 is placed on the Y-axis rails 53 and 54 so as to be movable in the Y-axis direction by wheels 55 and 56. The Y-axis motor is a servo motor 61. Therefore, fine position control of the carriage 30 in the Y-axis direction can be executed with high accuracy. The amount of movement of the carriage 30 is detected by the Y-axis encoder 63. The Y-axis encoder 63 has a gear, and when this gear meshes with a rack provided in parallel with the inner side surface of the rail beam 51, the movement amount of the carriage 30 is measured. The data of the movement amount measured by the Y-axis encoder 63 is also transmitted to the control device 70.

  The grinding wheel 32 is attached to the support column 34. The column 34 is attached to the carriage 30 by a Z-axis cylinder 38 so as to be movable up and down. Further, the carriage 30 is provided with a grinding wheel rotating motor 35 for rotating the grinding wheel 32 via a V belt 33 and a grinding pressing cylinder 36 for pressing the grinding wheel 32 during grinding. Further, as shown in FIG. 3, a Z-axis encoder 62 for detecting the height of the grinding wheel 32 is attached to the Z-axis cylinder 38. The Z-axis encoder 62 has a gear. When this gear meshes with a rack provided along the column 34, the amount of movement of the column 34 is measured, and the height of the grinding wheel 32 is detected.

  Further, the height position of the grinding wheel 32 is raised and lowered by the grinding pressing cylinder 36 independently of the height of the column 34. Therefore, a crimping position detecting device 37 for detecting the height position of the grinding wheel 32 from the inclination of the V belt 33 is provided. The control device 70 can calculate the position of the grinding wheel 32 on the Z-axis by acquiring both the detection positions from the Z-axis encoder 62 and the crimping position detection device 37.

  Further, although not shown in the drawings, a duct for collecting dust generated during grinding is attached to the grinding apparatus 10 at a position facing the grinding wheel 32, and the duct is connected to a dust collector.

The hardware configuration of the control device 70 will be described with reference to FIG.
The control device 70 includes a processor 71 connected to each other via a bus 78, a storage device 72 such as a memory and a hard disk, an external storage device 73 such as a DVD drive, an output device 74 such as a display and a printer, and an input such as a keyboard. A device 75 and an input / output interface unit 76 are included.
The input / output interface unit 76 includes an X-axis servomotor 25, a Y-axis servomotor 61, a Z-axis cylinder 38, a grindstone rotating motor 35, a grindstone pressing cylinder 36, an X-axis encoder 26, and a Y-axis encoder 63. Are connected to the Z-axis encoder 62 and the first and second laser distance meters 42 and 43.

  The processor 71 uses the input data from the X-axis encoder 26, the Y-axis encoder 63, the Z-axis encoder 62, and the first and second laser distance meters 42 and 43 to store a control program stored in the storage device 72. Thus, output control of the X-axis servomotor 25, the Y-axis servomotor 61, the Z-axis cylinder 38, the grindstone rotating motor 35, and the grindstone pressing cylinder 36 is performed.

  The processor 71 also determines the movement distance in the X-axis direction of the first and second laser distance meters 42 and 43 and the distance in the Y-axis direction between the first and second laser distance meters 42 and 43 and the slab side surface. Corresponding in the coordinate system. The X-axis position coordinates and the measured Y-axis coordinates of the first laser rangefinder 42 that measures each time at a pitch of about 10 mm are received and stored in the storage device 72 as XY coordinate data. The same applies to the second laser distance meter 43. As a result, the position of each part of the outline of the slab S can be specified on the XY coordinates.

The flow of the pressure bonding pressure control process by the control device 70 will be described with reference to FIG.
First, various parameters for crimping control are set (step S101). The parameter setting is manually input via the input device 74. The parameters are a crimping control position designation parameter D, a sample pitch parameter P for designating a pitch for obtaining a moving average sample, and a pressure control determination threshold value R.
The crimping control is performed to determine whether or not the grinding wheel 32 is at the end position, and when it is determined that the grinding wheel 32 is at the end, the pressure is reduced to a pressure at which the grinding wheel 32 does not drop abruptly (preferably, the crimping pressure Is set to zero). In this way, by performing edge determination separately from the XY coordinate data of the slab contour acquired by the laser distance meter, even for accidents such as measurement errors of the laser distance meter, movement of the slab after measurement, It becomes possible to avoid the grinding stone falling.

  Indicates edge judgment. In order to grind the surface of the slab S, the grinding wheel 32 presses the slab S from the Z-axis direction with a very large force. When the grinding wheel 32 moves to the vicinity of the end of the slab while grinding the slab surface, the slab S bends in the lower direction of the Z-axis. Therefore, when the Z-axis position of the grinding wheel 32 is lowered by continuously measuring the Z-axis position of the grinding wheel 32 using the crimping position detector 37 and the Z-axis encoder 62, the end of the slab It can be determined that there is a grinding wheel 32.

  On the other hand, since the surface of the slab S is not necessarily flat, it is possible to determine that the grinding wheel 32 is located at the end by the end determination process even though the grinding wheel 32 is not actually located at the end of the slab S. There is sex. Therefore, the crimping control start position designation parameter D is set, and a certain area is designated as the crimping control area from the end position acquired by the laser distance meter.

  The parameters D and P will be described with reference to FIG. (A) is a top view which shows D designation | designated area | region on the slab surface. The crimping control position designation parameter D is a parameter for designating a crimping control area for performing the crimping control of the grinding apparatus 10. As shown in the figure, the crimping control region 152 is set on the slab outline 151 measured by the laser, D (mm) inside from the slab end coordinates. When the grinding wheel 32 enters the region having the width D, the control unit 70 starts pressure control.

Specifically, the pressure-bonding control process performs the following pressure control determination.
Zf−Za ≧ R (Expression 1) At this time, the pressure of the grinding wheel 32 is set to zero.
Zf−Za <R (Formula 2) At this time, the pressure of the grinding wheel 32 is maintained and grinding is performed.

  As shown in the above equation, when the difference between the Z-axis position (Zf) obtained by moving average and the measured Z-axis position (Za) is larger than the threshold value R, the crimping pressure is set to 0 and smaller than the threshold value R. Continue grinding interruption. The reason why such a judgment formula is used is that, since the elasticity of the slab end portion increases, a variation larger than the moving average is caused.

The sample parameter P is a parameter for designating coordinates for obtaining a moving average sample. (B) is a side view which shows the D designation | designated area | region vicinity of slab. When the number of samples is 5, the acquired coordinates are specified by (Z1, X1) to (Z5, X5) when the grinding wheel 32 is displaced in the X-axis direction. Xn can be defined by the following equation.
Xn = P × n + D (Expression 3)
The same applies to the case of displacement in the Y-axis direction. Note that the start position for acquiring the moving average sample is shown as the sample data acquisition position 154 in FIG.

When the value of D is large, the control process is continuously executed from the front of the end. When the value of D is extremely small, the amount of control processing decreases, but if there is a discrepancy between the actual slab and the measured slab coordinates, the risk that the grinding wheel 32 will fall before the above control processing is executed. Will also increase.
When the value of P is large, the variation of the moving average is small, and in order to increase the prediction accuracy, it is necessary to set a large value for the threshold value R. On the other hand, when the value of P is small, the fluctuation of the moving average becomes large, and it is necessary to set the numerical value of R relatively small.
The values of D and P can be arbitrarily set so that appropriate pressure bonding control processing can be performed.

  Returning to step S102 in FIG. 5, the control program stored in the storage device 72 is activated. According to the control program, the processor 71 performs a measurement process of the contour of the slab S (step S102). In this process, the processor 71 drives the X-axis servomotor 25 to move the carriage 20 in the X-axis direction, thereby moving the first and second laser distance meters 42 and 43 attached to the carriage 20 to X. Move in the axial direction. Subsequently, the processor 71 performs control so as to measure the distance from the side surface of the slab S every time the first and second laser rangefinders 42 and 43 move by a predetermined distance in the X-axis direction. Thereby, the outline of the slab S is stored in the storage device 72 as XY coordinate data.

  Next, the processor 71 executes processing for calculating a grinding locus of the grinding wheel 32 (step S103). A grinding locus is determined as indicated by 153 in FIG. The grinding trajectory 153 is a trajectory of the grinding wheel 32 planned so that the entire surface of the slab S can be ground.

  The processor 71 executes grinding control of the grinding wheel 32 according to the grinding locus (step S104). The processor 71 controls the movement of the X-axis servomotor 25 in the X-axis movement operation, and controls the movement of the Y-axis servomotor 61 in the Y-axis movement operation, and starts the grinding wheel rotation motor 35 to perform grinding. The grindstone 32 is rotated.

  The grinding apparatus 10 performs the grinding with the grinding wheel 32, while confirming the position of the X axis or the Y axis, and determines whether or not it is the moving average sample acquisition start position (S105). That is, when the sample data acquisition position 154 in FIG. 6A is reached, moving average sample acquisition is started. When the moving average sample acquisition start position is reached, the processor 71 starts acquiring sample data (Zn, Xn). Specifically, when the position Xn = P × n + D shown in Expression 3 is reached, Xn of the sample data is obtained from the X-axis encoder 26 (including the Y-axis encoder 63 when moving in the Y direction). Obtained (step S106), the Z-axis coordinate Zn is obtained from the Z-axis encoder 62 and the crimping position detecting device 37 (step S107). And when the grinding stone 32 moves to the said position, step S106 and S107 are repeated.

Further, the grinding wheel 32 is moved, the position of the X axis or the Y axis is confirmed, and it is determined whether or not the position is the crimping control processing start position (S108). That is, when it comes to the crimping control region 152 in FIG. 6A, the above-described crimping control process is executed. The processor 71 calculates the predicted moving average height (Zf) from the acquired sample data (S109), and acquires the actual height position (Za) (S110). Next, the processor 71 obtains the actual height. As described above, when Zf (moving average calculated height) −Za (actual height) ≧ R (threshold) is satisfied (step S111), the pressure of the grinding wheel 32 is set to zero (step S112). . When not established, the grinding process is further continued, and when Za is changed and the equation is established, the pressure of the grinding wheel 32 is set to zero (step S112).
In step S108, if the grinding wheel 32 is not at the press-bonding control processing start position, sample data is acquired (step S106), and the grinding wheel 32 is further moved (step S107).

  As described above, this grinding apparatus or grinding control method prevents the grinding wheel from falling and prevents the grinding process from being delayed due to the grinding stone falling by judging the position of the slab end from the fluctuation of the grinding wheel height. Became possible.

Further, even when the crimping pressure becomes zero by step S112, the processor 71 moves the grinding wheel 32 according to the grinding locus, and when Zf−Za <R is satisfied, the crimping pressure is again increased to a predetermined value and grinding is performed. continue.
As described above, since the grinding stone is prevented from dropping and the slab grinding process is continued without interrupting the grinding process, it is possible to prevent a reduction in the grinding efficiency due to the occurrence of the interruption process.

  In step S112, the pressing pressure is set to zero. However, when the grindstone is actually dropped, the pressing pressure may be lowered to a level that does not damage the grindstone.

  The embodiments described above are merely given as typical examples, and variations and variations thereof will be apparent to those skilled in the art. Those skilled in the art will depart from the principles of the present invention and the scope of the invention described in the claims. Obviously, various modifications of the above-described embodiment can be made.

FIG. 1 is a plan view showing an outline of the grinding apparatus 10. FIG. 2 is a side view showing the outline of the grinding apparatus 10 from the left side of the X axis. FIG. 3 is a side view showing the outline of the grinding apparatus 10 from the lower side of the Y-axis. FIG. 4 is a diagram illustrating a hardware configuration of the control device 70. FIG. 5 is a flowchart of the pressure-bonding pressure control process by the control device 70. FIG. 6 is a diagram showing the crimping control position designation parameter D and the sample pitch parameter P.

Explanation of symbols

S Slab 10 Grinding device 12, 14 Conveyor 16, 18 X-axis rail 20 Cart 25 X-axis servo motor 30 Carriage 32 Grinding wheel 33 V-belt 34, 57, 58 Strut 35 Grinding wheel rotation motor 36 Grinding wheel pressing cylinder 37 Crimping Position detection device 38 Z-axis cylinder 42, 43 First and second laser distance meters 51, 52 Rail beam 53, 54 Y-axis rail 61 Y-axis servo motor 70 Control device

Claims (6)

A grinding wheel for grinding the surface of the slab,
A measuring device for measuring the contour of the slab;
A grindstone pressing device that press-bonds the grinding wheel to the surface of the slab;
A pressure bonding position detecting device for detecting a height of a pressure bonding position of the grinding wheel;
Moving means for moving the grinding wheel on the surface of the slab;
The height of the crimping position of the grinding wheel is stored within a predetermined distance from the end of the measured contour, and the difference between the average height of the stored crimping position and the actual pressure position of the grinding wheel is stored. A controller that controls whether or not the pressure of the grinding wheel is lowered when the difference is equal to or greater than the threshold;
Grinding device having.   The grinding apparatus according to claim 1, wherein when the difference is less than a threshold value, the pressure of the grinding wheel is maintained.   The grinding apparatus according to claim 1, wherein the determination is performed within a predetermined distance from an end portion of the measured contour. A grinding control method using a grinding device for grinding the surface of a slab,
Measuring the contour of the slab,
Crimping the grinding wheel to the surface of the slab,
Moving the grinding wheel on the surface of the slab,
Detect the height of the grinding wheel's crimping position,
The height of the crimping position of the grinding wheel is stored within a predetermined distance from the end of the measured contour, and the difference between the average height of the stored crimping position and the actual pressure position of the grinding wheel is stored. A grinding control method for determining whether or not the difference is equal to or greater than a threshold value and, if the difference is equal to or greater than the threshold value, controlling to reduce the pressure of the grinding wheel.   The grinding control method according to claim 4, wherein when the difference is less than a threshold value, the pressure of the grinding wheel is maintained.   The grinding control method according to claim 4, wherein the determination is performed within a predetermined distance from an end portion of the measured contour.

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