JP2007083249A - Laser beam machining device and laser beam machining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam machining device and a laser beam machining method where the error or the like characteristic of a laser beam machining device are corrected, and a product can be machined with high precision. <P>SOLUTION: The laser beam machining device for machining a work is provided with: a measuring means 13 for measuring the dimensions after machining to a work 2; and a calculating means 4 where prescribed correction calculation is performed using the measured data of prescribed important dimensions of the work 2 measured by the measuring means 13. The machining of the work is performed by machining data as the standards; an error between the prescribed important dimensions expressed by the machining data as the standards and the prescribed important dimensions expressed by the measured data measured in the work after the machining is obtained in accordance with a machining line width; based on the error, new machining data are prepared by the calculating means 4; and, using the new machining data, the machining of the work is performed, so as to correct a machining error. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a laser processing apparatus and a laser processing method for performing processing using a laser, and relates to a laser processing misalignment correction technique for correcting processing misalignment and improving processing accuracy.

  In recent years, laser processing apparatuses are used for applications such as drilling, cutting, welding, marking, and trimming. As a method for two-dimensionally scanning a laser beam on a workpiece, there are a method using a galvano scanner, a method for moving a stage on which a workpiece is set, and the like. The method using a galvano scanner is widely used because it is faster, more accurate, simpler in configuration and smaller than the stage method.

  The configuration in the case where the galvano scanner is used will be briefly described. Laser light output from the laser oscillator is swung in the X direction and the Y direction by two galvano scanners, respectively. The laser beam is irradiated onto the workpiece and processed by an fθ lens designed to focus on the product and to have a constant scanning speed at the periphery and the center.

  However, due to its structure, it is inevitable that an error of several tens to several hundreds of microns occurs in the laser beam processing area. The main causes of the error are the use of two mirrors in the X and Y directions, so pincushion distortion caused by the relationship between the control angle of the scan mirror and the processing position, and the linearity in the design of the fθ lens. One example is geometric distortion caused by errors. In response to this error, when performing hole machining, various methods have been proposed for measuring the hole position deviation after machining and feeding it back to the machining apparatus.

  For example, a method that corrects the hole position for machining the product by machining a small number of test pattern holes in a grid, complementing the data between the test patterns by spline interpolation or nonlinear multiple regression analysis from the measured hole positions (for example, Patent Document 1 and Patent Document 2). In addition, a method has been proposed in which the positions of holes processed into a product are measured for a plurality of workpieces, the positional deviation is statistically calculated, and an optimal correction position is obtained (for example, see Patent Document 3).

In addition, the configuration of the laser processing apparatus itself is modified, the control method of the galvano scanner is configured with a digital circuit, and a correction unit for device-specific distortion such as lens distortion and galvano scanner characteristics is added. A method for processing a product has also been proposed. (For example, see Patent Document 4)
Japanese Patent Laid-Open No. 10-301052 JP 2002-316288 A JP 2004-322149 A JP 2002-333594 A

  However, unlike hole drilling, pattern drawing / machining is a process of continuous straight lines or curves, so correction of only specific coordinates makes it difficult to improve the accuracy of the position of the pattern and the shape of the pattern itself. Since it is necessary to improve the accuracy of each component or to add a correction function to the fundamental part of the apparatus, there has been a problem that development requires a lot of cost and time.

  SUMMARY OF THE INVENTION An object of the present invention is to solve a conventional problem, and to provide a machining deviation correction method by laser machining and a laser machining apparatus for correcting machining deviation and improving machining accuracy.

  In order to solve the conventional problems, a laser processing apparatus of the present invention includes a pair of galvano scanners for causing laser light emitted from a laser oscillator to swing in the X-axis direction and the Y-axis direction on a work surface, An fθ lens for condensing and irradiating a laser beam from a galvano scanner onto the work surface, a measuring means for measuring a dimension of the work after processing, and a predetermined shape of the work measured by the measuring means And a calculation means for obtaining a correction data by performing a predetermined correction calculation using the measurement data of the dimension, processing the workpiece with the reference processing data, and a predetermined shape represented by the reference processing data An error between the dimension and the predetermined shape dimension represented by the measurement data measured on the workpiece after machining is obtained according to the machining line width, and new machining data is obtained by the calculation means based on the error. Forms, to correct the machining error perform machining of the workpiece by using the new processing data.

Further, the laser processing method of the present invention is a processing data serving as a reference in a laser processing method for processing a workpiece by scanning the laser beam emitted from a laser oscillator in the X-axis direction and the Y-axis direction on the workpiece surface. The workpiece is processed according to the above, and an error between the predetermined shape dimension represented by the reference machining data and the predetermined shape dimension represented by the measurement data measured on the workpiece after machining is determined in accordance with the machining line width, A predetermined correction calculation process is performed based on the error, a new corrected machining data is created based on the calculation process, and the workpiece is machined using the new corrected machining data to reduce a machining error. It is characterized by correction.
Further, the laser processing method of the present invention is a processing data serving as a reference in a laser processing method for processing a workpiece by scanning the laser beam emitted from a laser oscillator in the X-axis direction and the Y-axis direction on the workpiece surface. The workpiece is machined, the shape of the workpiece is measured using the imaging means, the dimension of the workpiece is measured, the distance or the segment length of the line segment that identifies the measured shape is calculated, and becomes the reference An error with the shape of the machining data is calculated, a predetermined correction calculation process is performed based on the error, a new corrected machining data is created based on the calculation process, and the new corrected machining data is And machining the workpiece to correct a machining error.

  According to the laser processing apparatus or the laser processing method of the present invention, the error inherent to the laser processing machine is mainly caused by the pincushion distortion caused by using the pair of galvano scanners and the linearity error in the design of the fθ lens. The product can be processed with high accuracy.

Hereinafter, embodiments of a laser processing apparatus and a laser processing method of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram for explaining a positional deviation correction method of a laser processing method in Embodiment 1 of the present invention, and FIG. 2 schematically shows a schematic configuration of a laser processing machine of a laser processing apparatus in Embodiment 1 of the present invention. FIG.

  FIG. 3A is an example of processing data before correction in the first embodiment of the present invention, FIG. 3B is a diagram showing a shape actually processed, and FIG. 4A is a diagram of the present invention. FIG. 4B shows an example of processed data after correction in the first embodiment. FIG. 4B is a diagram showing an actually measured shape processed by the corrected processed data and corrected for errors, and FIG. 5 shows the present invention. It is a figure which shows the shape dimension of the important part of the product in Example 1 of.

  FIG. 6 is a flowchart showing the flow of correction processing of the laser processing method in Embodiment 1 of the present invention.

  FIG. 7 is a diagram showing a schematic configuration of the entire laser processing apparatus in which an image processing unit is added to the laser processing unit in the first embodiment of the present invention, and FIG. 8 is an image processing apparatus of the laser processing method in the first embodiment of the present invention. FIG. 9 is a diagram showing an example of the result of the correction work in the first embodiment of the present invention.

  FIG. 10 is a diagram for explaining the correction calculation (1) of the laser processing method according to the first embodiment of the present invention, and FIG. 11 illustrates the correction calculation (2) of the laser processing method according to the first embodiment of the present invention. FIG. 12 is a diagram for explaining the correction calculation (3a) of the laser processing method in Embodiment 1 of the present invention, and FIG. 13 is the correction calculation (3b) of the laser processing method in Embodiment 1 of the present invention. It is a figure for demonstrating.

  FIG. 14 is a diagram for explaining a method for creating machining data by enlargement / reduction in the first embodiment of the present invention, and FIG. 15 is a method for creating machining data by functionalizing line segments in the first embodiment of the present invention. It is a figure for demonstrating.

  The present invention is a method for correcting a processing deviation caused by distortion or the like generated in an optical system of a laser processing machine 1, and a laser processing machine 1 according to the present invention includes a pair of galvanometers as shown in FIG. A scanner and an fθ lens 9 are used. The laser processing apparatus 1 will be briefly described with reference to FIG. 2. A laser beam 12 emitted from a laser oscillator 6 is reflected by a galvano scanner (X axis) 7 having a mirror that is driven to rotate, and is directed in accordance with the mirror angle. , And enters the galvano scanner (Y axis) 8.

  The laser beam 12 is reflected again according to the mirror angle of the galvano scanner (Y axis) 8 and changes its direction in the direction of the product 10 that is the workpiece, and passes through the fθ lens 9 and is focused on the product 10. The fθ lens 9 is designed so that the laser beam 12 is focused on the flat product 10 and the scanning speed is constant between the peripheral part and the central part.

  The pair of galvano scanners is controlled by the control unit 11. By giving arbitrary processing data to the control unit 11, each galvano scanner can take an angle according to the shape based on the processing data and can move the laser beam 12 to a desired position. Further, since the control unit 11 also controls the laser oscillator 6, it is possible to irradiate the laser beam 12 having an arbitrary intensity at an arbitrary timing according to the position of the galvano scanner. That is, the product can be irradiated with the same shape represented by the processing data, and the product 2 can be processed. In addition, depending on the intensity of the laser beam 12, various types of processing such as cutting, marking, and trimming can be performed.

  In the correction work according to the present invention, it is not necessary to prepare a dedicated test work or test processing pattern, which is different from the material of the product, and can be performed in the same work as when processing the product. The work procedure will be described. First, machining data identical to the target shape is input to the machining apparatus, and machining is performed on the same test workpiece as the actual product. For example, when processing into a shape having the important part shape dimensions (dimension A, dimension B) shown in FIG. 5, the shape of the machining data used at the time of the first correction work is the shape according to the target dimension required as a product. FIG. 3 (a).

  The relationship between the target data T for obtaining the target dimension and the processing data D will be described in detail. When forming a recess having a target dimension T = 1.5 mm, the processing data is assumed to have a processing line width W of 0.12 mm. When D is D = T−W = 1.5−0.15 = 1.35 mm, a result close to the target data T is obtained in the actual measurement data R from the first processing. That is, a processing result close to R = T = 1.5 mm is obtained. However, in actual work, machining data is automatically created in the processing unit of the laser machining apparatus (software on the PC, etc.), so machining data of D = 1.38 is created manually only for the first work. Is easier to automatically create D = 1.5. Further, even if the setting changes, there is no guarantee that the line width W will always be the same. Therefore, when correction is started with a new device configuration, correction is started with D = T.

  The processing data is composed of a plurality of pattern shape data composed of figures obtained by dividing the final processing shape, and data representing the respective arrangement coordinates.

  The actual correction work will be described below. First, the same processing data as the reference target data before correction is input to the processing apparatus, and laser processing is performed on the test workpiece.

  Next, a test work machined based on the machining data is measured by the measuring unit. Here, for example, when the predetermined important dimensions are the pitch A and the width B in FIG. 5, it is sufficient to measure only the pitch A and the width B. However, an error occurs in the processed shape without fail. When processing a product, it is necessary to correct the processing data. When machining a test workpiece using the machining data of FIG. 3A, for example, as shown in FIG. 3B, the width dimension B of the recesses at both ends of the test workpiece is widened, and the portion of the pitch dimension A closer to the center is reduced. It is processed in the shape. The error that occurs in this case is that the control unit 11 operates the galvano scanner and tries to scan the workpiece with the same shape as the machining data with the laser beam, but the position where the laser is actually irradiated differs from the machining data. Caused by This is mainly due to pincushion distortion caused by the use of a pair of galvano scanners as described above and linearity errors in the design of the fθ lens 9, and the accuracy of each part and the relative position of the mounting position. It is also affected by deviation. This error can be reduced by improving the accuracy of a single component used in the laser processing machine 1 or its assembly accuracy, but it always occurs in terms of configuration.

  The measured important dimension is input to the calculation unit 4. In the calculation unit 4, the measured dimension is determined from the target dimension necessary for the product, the dimension of the machining data before correction that is actually processed, and the dimension that is actually measured and measured by the measuring unit 3. New machining dimensions corrected so as to be identical to each other are calculated, and new machining data including a plurality of pattern shapes and arrangement coordinate data corrected based on these machining dimensions is created.

  In FIG. 4A, the dimension B shown in FIG. 5 is reduced to the dimension B at both ends, and new machining data in which the dimension B and the dimension A at the center are expanded is input to the machining apparatus, and machining to a new test workpiece is performed. Then, for example, a processing result as shown in FIG. This is close to the shape as the target size required for the product shown in FIG.

  In this method, a new processing dimension is estimated from the target dimension necessary for the product, the dimension of the processing data before correction that is actually processed, and the dimension actually measured and measured by the measuring unit 3. Therefore, even if the specified accuracy cannot be obtained in one operation, it is possible to repeat the processing on these test workpieces until the required accuracy can be obtained. As an example, the result of repeated correction work is shown in the graph of FIG. In the correction of this graph, there are 14 dimensions of 7 mm, and the tolerance is ± 25 μm. When machining with the machining data in the initial state, it was greatly different from the standard, but all 14 locations reached the standard with the first correction data. However, both the maximum and minimum values are very close to the standard value, and when many processes are performed, there is a high possibility that the standard will be deviated for some reason. When the correction work is repeated here, the error gradually decreases and becomes within ± 10 μm in the test work processing based on the third correction data, and the standard deviation is also small, and the dimensional accuracy is improved according to the number of corrections. You can see that

  Moreover, the calculating part 4 is realizable with a personal computer, for example, and may be integrated with the control part 11 of the laser beam machine shown in FIG.

  An example of a specific calculation method for dimensional correction in the calculation unit 4 is shown below.

  In laser processing, because of the influence of the laser spot system, a line width in processing is always required, and this must be taken into account when performing dimension correction. In particular, when the dimension to be processed becomes small, the proportion of the line width relatively increases, and the influence of the line width is remarkable.

  Assuming that the target dimension is T, the current machining data dimension is D, the actually measured dimension is R, and the machining line width is W, new corrected machining data to be machined is obtained by the following equation. Further, it is assumed that the actually measured dimension of the workpiece machined with the machined data after correction becomes a target dimension T that is a dimension necessary for the product.

  (1) When the target dimension T exceeds about 20 times the processing line width W and is relatively large, the corrected processing data D1 may be expressed by the following formula.

D1 = D × T / R (Formula 1)
This equation will be described with reference to FIG. The ratio between the machining data D and the actually measured dimension R is considered to be equal to the ratio between the corrected machining data D1 and the target dimension T. Therefore, D: R = D1: T
Therefore, the above equation is derived. Although the line width W is not taken into account, since the dimensions themselves are relatively large, the error due to the distortion inherent to the device becomes larger than the influence of the line width, and the error due to the influence of the line width does not surface.

  (Formula 1) indicates that when the measured data R is larger than the processed data D when processed with the processed data D, the corrected data is closer to the target data T if the corrected processed data is smaller than D. On the contrary, when the measured data R is smaller than the processed data D when processed with the processed data D, it indicates that the corrected processed data is closer to the target data T if the corrected processed data is larger than D. It can be made smaller.

  (2) If the target dimension T is 10 to 20 times as large as the processing line width W, the corrected processing data D2 may use the following formula.

D2 = D−R + T
This equation will be described with reference to FIG. When the size is reduced, the influence of the line width W is increased in the method using the ratio as in the formula (1). However, since it is possible to complete the work in a short time when the number of measurement points is small, an equation using a difference is used. Specifically, if an error between the actually measured dimension R and the target dimension T is δ, δ = RT−T
Can be expressed. Therefore, it is preferable to change the dimension of the machining data D by the magnitude of δ.
D2 = D−δ = DR + T (Expression 2)
It becomes.
(Equation 2) indicates that when the measured data R is larger than the processed data D due to processing, the corrected processing data is smaller than the difference δ = (R−T) and becomes closer to the target data T. Show. On the contrary, when the actual measurement data R is smaller than the machining data, if the corrected machining data is larger than the difference δ = (T−R), it indicates that it is closer to the target T, resulting in an error. It can be made smaller.

  (3) If the dimension is further reduced and the target dimension T is less than 10 times the processing line width W, the influence of the line width W becomes large and cannot be ignored in calculation. This is measured and used for correction. . In this case, it is necessary to change the formula used depending on the shape of the portion to be corrected.

  (3a) When processing a concave shape, the corrected processing data D3a may use the following equation.

D3a = D × (T−W) / (R−W) (Formula 3)
This equation will be described with reference to FIG. In the case of the concave shape, as shown in FIG. 12 (a), the actual measurement dimension R has an interval L between portions where the spot center of the laser beam has actually passed and a half of the line width W at both ends. Is. Therefore, as shown in FIG. 12 (b), the measured dimension R in consideration of the line width W is R = L + W
It becomes the relationship. Further, the line width W does not change, and the target dimension T in consideration of the line width W is as follows when the interval of the trajectory through the spot center at this time is L0. T = L0 + W
Here, when the ratio calculation is performed as in (1), D: L = D3a: L0
It becomes. Here, if L and L0, which cannot be measured by actual measurement, are deleted, D: (R−W) = D3a: (T−W)
Thus, the above equation is derived.

  (3b) When processing a convex shape, the following formula may be used.

D3b = D × (T + W) / (R + W) (Formula 4)
This equation will be described with reference to FIG. In the case of a convex shape, as shown in FIG. 13A, the corrected machining data D3b has an actually measured dimension R that is an interval L between portions where the laser beam spot center has actually passed and a half of the line width W at both ends. The size of is removed. Therefore, as shown in FIG.
R = L-W
It becomes. As in (3a), the target dimension T is T = L0−W
It becomes. From these, D: (R + W) = D3b: (T + W)
Thus, (Equation 4) is derived.

  However, in the case of correction of a pitch dimension or the like that is not affected by the line width, since the case of (3) cannot be used, the equation of (2) is used.

  Note that the use of the above formulas (1) to (3) is not necessarily strict, and can be used according to actual processing conditions. For example, since it is difficult to measure the line width W when cutting, Equation (2) may be used instead of Equation (3), and it is known that the required accuracy is high and the number of corrections is large. In order to simplify the work, the formula (2) is used instead of the formula (3). Moreover, you may use formulas other than (1)-(3) according to process conditions separately.

  When new machining data of the important dimension part of each part is obtained by the formula for performing these dimension corrections, new machining data is created based on this. By using this new processing data and performing processing with a laser processing machine, it becomes possible to perform processing with dimensions close to the target.

  An example of a method of creating machining data from the corrected machining dimensions obtained by the calculation unit 4 is shown below.

  As described above, the calculation unit 4 is inputted with the measured dimension R of the test workpiece, and automatically calculates the important part from the inputted dimension R of the test workpiece, the target dimension T, and the dimension D used for processing. It has a function to obtain new machining dimensions. In general, shape data is compatible with files created by CAD, and shape data is usually created by CAD. For this reason, it is possible to manually create a plurality of shape data and their arrangement coordinate data from new machining dimensions. However, if the machining shape is complicated, the number of divided shape data increases. Therefore, a long time is required for the work, and the possibility of human error is increased. Therefore, an efficient and accurate correction operation can be performed by adding a function for automatically creating machining data composed of a plurality of shape data and arrangement coordinate data based on a new machining dimension to the calculation unit 4.

  The simplest way to create new deformed shape data is to simply scale the figure, that is, to convert each coordinate value of the line segment by affine transformation, which can be used in most cases. is there. At this time, since the magnification varies depending on the axial direction in most cases, it is desirable to deform the X-axis direction and the Y-axis direction of the shape with independent magnifications.

  In addition, since the coordinates at which each piece of shape data is to be arranged change with the deformation of the shape data, the arrangement data is also corrected in accordance with the deformation of the shape data.

  A specific example will be described with reference to FIG. 14. When the dimension A representing the pitch dimension and the B representing the groove shape in FIG. 5 are changed, the shape data is divided as shown in FIG.

  In FIG. 14A, the recess shape (groove shape) is expressed by the X direction distance and the Y direction distance, that is, the groove width (X direction distance) and the groove depth (Y direction distance) which are the recess shape. ) Is used.

  When creating the groove shape data from the dimension B which is the groove width, the groove shape corresponding to (1) to (3) is enlarged (reduced) as shown in FIG. Coordinates (x1, y1) are converted into new coordinates (x2, y2) by the following formula. At this time, a is a magnification in the X direction, and b is a magnification in the Y direction. That is, x2 = a × x1, y2 = b × y1.

  When creating shape data in which the dimension B which is the width is corrected, enlargement (reduction) is performed only in the X-axis direction corresponding to the groove width. Accordingly, a in the X direction is set based on the ratio between the dimension before correction and the dimension after correction, and since there is no need to convert the Y direction, b = 1, and x2 = a × x1, y2 = y1.

  By performing the above calculation for each groove, the groove processing data is created. The coordinates for arranging the processing data are obtained by the corrected pitch of the dimension A and described in the arrangement coordinate data. Further, with respect to the other line segments, the corrected machining data is generated by creating the line segments so as to connect the shapes of the grooves.

  However, in the shape data, there may be a portion where a problem occurs when it is deformed. In such a case, the shape line segment is functionalized, and only the deformable line segment is enlarged or reduced. If the part that cannot be deformed is translated to maintain the shape, it is possible to cope with the necessary part while maintaining the shape.

A specific example in such a case will be described with reference to FIG. For example, it has a groove shape as shown in FIG. 15 (a), and the line segments (1) and (4) cannot be extended for the convenience of the product, and the line segments (2) and (3) cannot be extended. It is possible but the angle cannot be changed, and the groove width between the line segments (1) and (4) is corrected. When there are such restrictions, as shown in FIG. 15B, the line segments (1) and (4) move in the X-axis direction, and the line segments (2) and (3) extend or shrink. . Accordingly, each line segment is functionalized as follows. It is assumed that the coordinate system shown in FIG. 15C is taken, c to f are parameters such as coordinate values shown in the figure, and ef are constants.
That is, x = −d (−c ≦ y ≦ 0) regarding the line segment (1), y = −fx−c (−d ≦ x ≦ 0) regarding the line segment (2), and y = − regarding the line segment (3). For fx−c (0 ≦ x ≦ d) and line segment (4), the function is expressed as x = d (−c ≦ y ≦ 0).

  Here, assuming that the dimension of the corrected groove width is obtained by the correction calculation, the value of d is determined to be half of the groove width. Then, since it is the e constant, the coordinates (−d, −e) are determined, and the value of c is obtained by calculating c = −e−fd.

  Since the formulas representing the respective line segments are determined by these calculations, the coordinate values at both ends thereof are obtained, and processing data in which only the line segments (2) and (3) as shown in FIG. It becomes possible. The creation of the arrangement coordinate data is the same as the case of performing the enlargement / reduction process.

  With these methods, it is possible to easily obtain machining data that can accurately machine products by measuring the dimensions of the test workpiece and inputting it into the arithmetic unit without improving the laser processing machine itself. Is possible. Furthermore, in the correction work, it is not necessary to use a work made of a special material dedicated to the test or to use a test-dedicated pattern, so that an efficient work can be performed.

  Here, the procedure will be described with reference to the flowchart of FIG.

  In Step 1, basic processing data is input to the control unit 11 of the laser processing machine 1 shown in FIG. At this time, as described above, machining data having a dimension as a target as a target is input.

  In Step 2, processing based on the processing data is performed with a laser processing machine, and the test work in FIG. 1 is created.

  In Step 3, for example, the important dimensions shown in FIG. 5 are measured by the measuring unit 3 for the processed test workpiece.

  In Step 4, it is determined whether the measured critical dimension satisfies the standard as the product accuracy. When machining data having the same shape as the target input in Step 1 is used, in most cases, the process proceeds to the next Step 5 without satisfying the standard.

In Step 5, the calculation unit 4 to which the measured actual dimension is input compares and calculates the machining dimension and the target dimension, and obtains a new machining dimension that makes the actual dimension equal to the target dimension.
In Step 6, new processing data (shape data and arrangement data) is created based on the new processing dimensions and input to the control unit 11 of the laser processing machine 1.

  Based on this new machining data, the operations of Step 2 to Step 4 are performed again. If the critical dimensions meet the standard in Step 4, the machining data correction work is completed. If the standard is not satisfied, it is possible to obtain the required accuracy by repeating the correction work with the test work.

  Up to this point, we have described a method for correcting machining deviations caused by distortion inherent to the galvano scanner and fθ lens 9 of the laser processing device when the device is installed or when the settings are changed. In this processing, distortion of the apparatus itself occurs due to a change in the ambient temperature at the place where the processing apparatus is installed and heat generation of the processing apparatus itself, resulting in a processing shift. For example, when the temperature change of the laser processing apparatus occurs at 1 ° C., the processing deviation is about 2 to 5 μm. For this reason, there is a high possibility that the processing dimension is out of the standard under conditions where the temperature change is large.

  In addition to the temperature change, the adjustment state fluctuates over time from the initial adjustment due to aging of the components of the laser processing apparatus. That is, since the component parts of the laser processing apparatus generally change with time, the time-dependent fluctuation of the part itself is superimposed on the signal, causing an error in the position control of the galvano scanner, resulting in a position shift.

  When processing deviation occurs due to the above reasons, an image processing unit 13 is provided after the step of processing the product with the laser processing apparatus 1, and the processing area of the processed product is imaged by the image processing apparatus, Predetermined image processing is performed to determine important dimensions in the product. The quality of the product is judged based on this dimension, and if the product is out of the standard, the product is removed as a defective product, and the corrected machining dimension is obtained based on the dimension measured by the calculation unit 4. Create corrected machining data. By using the apparatus configured in this way, it is possible to always create a product that satisfies the standard.

  This will be described with reference to the flowchart shown in FIG.

  Usually, in the process of mass production, the product is processed in Step 7 using previously corrected processing data. In Step 8, the processed product is picked up by a CCD camera or the like of the image processing device 13, and in Step 9, the image is image-processed to acquire important dimensions. In Step 10, it is determined whether the important dimension satisfies the standard. Since the machining is performed with the machining data that has already been corrected, the work is usually finished for this product. However, if a processing deviation occurs due to a temperature change or the like and deviates from the standard, Step 11 obtains a new processing dimension from the processing dimensions, measured dimensions, and target dimensions. Based on the new machining dimensions, the machining data is corrected in Step 12 and transferred to the control unit 11 of the laser beam machine 1. Thereby, the processing data stored in the control unit 11 of the laser processing machine 1 becomes processing data that can always create a product that satisfies the standard.

  By adopting such a configuration, it is possible to always perform processing with accuracy even when a temperature change or a secular change occurs.

  The processing deviation correction method of the laser processing apparatus according to the present invention has a function of correcting an error inherent to the laser processing apparatus and processing a product with high accuracy, and is useful as a processing deviation correction method of the laser processing apparatus.

The figure for demonstrating the position shift correction method of the laser processing method in Example 1 of this invention. The figure which shows typically schematic structure of the laser processing machine of the laser processing apparatus in Example 1 of this invention. (A) The figure which shows an example of the process data before correction | amendment in Example 1 of this invention, (b) The figure which shows the shape actually processed. (A) The figure which shows an example of the process data after correction | amendment in Example 1 of this invention, (b) is a figure which shows the measurement shape of the state processed by the process data after correction | amendment, and the error was correct | amended. The figure which shows the geometrical dimension of the important part of the product in Example 1 of this invention The flowchart which shows the flow of the correction process of the laser processing method in Example 1 of this invention. The figure which shows schematic structure of the whole laser processing apparatus which added the image process part to the laser processing part in Example 1 of this invention. The flowchart which shows the flow of the whole process at the time of adding the image processing apparatus of the laser processing method in Example 1 of this invention. The figure which shows an example of the result of the correction | amendment work in Example 1 of this invention. The figure for demonstrating the correction calculation (1) of the laser processing method in Example 1 of this invention The figure for demonstrating the correction calculation (2) of the laser processing method in Example 1 of this invention The figure for demonstrating the correction calculation (3a) of the laser processing method in Example 1 of this invention The figure for demonstrating the correction calculation (3b) of the laser processing method in Example 1 of this invention The figure for demonstrating the method of producing process data by the expansion / contraction in Example 1 of this invention. The figure for demonstrating the method of producing process data by functionalization of the line segment in Example 1 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser processing machine 2 Product 3 Measurement part 4 Calculation part 5 Processing data 6 Laser oscillator 7 Galvano scanner (X axis)
8 Galvano scanner (Y axis)
9 fθ lens 11 control unit 12 laser beam 13 image processing unit 14 laser spot 15 scan locus

Claims (8)

A pair of galvano scanners for causing the laser light emitted from the laser oscillator to swing in the X-axis direction and the Y-axis direction on the workpiece surface;
An fθ lens for condensing and irradiating the work surface with the laser light from the galvano scanner;
A measuring means for measuring the dimension of the workpiece after machining;
Calculation means for obtaining correction data by performing a predetermined correction calculation using measurement data of a predetermined shape and dimension of the workpiece measured by the measurement means,
Machining the workpiece based on the standard machining data,
An error between a predetermined shape dimension represented by the reference machining data and a predetermined shape dimension represented by measurement data measured by the workpiece after machining is determined according to the machining line width,
Based on the error, create new machining data with the calculation means,
A laser processing apparatus that processes the workpiece using the new processing data and corrects a processing error. In the correction calculation, T is a target dimension which is a final product dimension, D is a dimension of current machining data, R is a dimension represented by measurement data obtained by actual measurement, and W is a line width generated by machining. If the corrected new dimensions to be processed shown in the following equation are D1, D2, D3a, and D3b,
D1 = D × T / R
D2 = D- (RT)
D3a = D × (T−W) / (R−W)
D3b = D × (T + W) / (R + W)
The laser processing apparatus according to claim 1, wherein the calculation is performed using any one of the mathematical formulas. 2. The laser processing apparatus according to claim 1, wherein the shape dimension is a width of a concave portion, an interval between widths of convex portions, or a pitch interval of a repetitively continuous shape. In a laser processing method for processing the workpiece by scanning the laser beam emitted from the laser oscillator in the X-axis direction and the Y-axis direction on the workpiece surface,
Machining the workpiece based on the standard machining data,
An error between a predetermined shape dimension represented by the reference machining data and a predetermined shape dimension represented by measurement data measured by the workpiece after machining is determined in accordance with the machining line width,
Perform a predetermined correction calculation process based on the error,
Create new corrected machining data based on the calculation process,
A laser processing method, wherein the processing error is corrected by processing the workpiece using the new corrected processing data. In the correction calculation, T is a target dimension which is a final product dimension, D is a dimension of current machining data, R is a dimension represented by measurement data obtained by actual measurement, and W is a line width generated by machining. If the corrected new dimensions to be processed shown in the following equation are D1, D2, D3a, and D3b,
D1 = D × T / R
D2 = D- (RT)
D3a = D × (T−W) / (R−W)
D3b = D × (T + W) / (R + W)
The laser processing method according to claim 4, wherein the laser processing method is calculated using any one of the following mathematical formulas. The laser processing method according to claim 5, wherein the shape dimension is a width of a concave portion, an interval between widths of convex portions, or a pitch interval of a repetitively continuous shape. In a laser processing method for processing the workpiece by scanning the laser beam emitted from the laser oscillator in the X-axis direction and the Y-axis direction on the workpiece surface,
Machining the workpiece based on the standard machining data,
Measure the shape of the workpiece using the imaging means,
Calculate the distance or length of the line segment that identifies the shape of the measured shape,
Calculate an error from the shape of the reference machining data, perform a predetermined correction calculation process based on the error,
Create new corrected processing data based on the arithmetic processing,
A laser processing method, wherein the processing error is corrected by processing the workpiece using the new corrected processing data. The laser processing method according to claim 7, wherein the correction calculation processing performs line segment expansion / contraction processing corresponding to a processing line width.

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