JPH022669B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for processing a workpiece such as a press die using an automatic grinding machine.

Conventionally, the grinding (polishing) work of the curved surface of a press die that has already undergone the specified NC processing is done using a spotting model (combination model) of the curved surface of the press die.
Rotary grinding tools (sanders, grinders), files, whetstones, etc. are inspected based on the operator's sensual inspection, such as red contact inspection to check the adhesion state of Komyotan, visual or tactile inspection of the curved surface of the press mold, etc. This is done manually by the operator, and the following problems arise.

(1) In press mold curved surface grinding after model matching,
There is no standard model, and therefore, the quality of the press mold, that is, the elimination of surface irregularities, shrinkage, elongation, bending, etc., is done through qualitative sensory tests by skilled workers. There are variations in image quality.

(2) The above-mentioned curved surface grinding is carried out by the muscular labor of skilled workers, resulting in a process that takes a long time and causes great fatigue for the workers.

(3) With conventional grinding machines using rotary grinding tools, it is impossible to grasp the actual amount of grinding of the workpiece in relation to the pressure of the abrasive material (abrasive material), the number of movements, etc., and it is difficult to create the correct curved surface shape. is becoming difficult.

(4) In order to grind with high precision, it is necessary to measure the amount of grinding by the abrasive material during the grinding process and correct the amount of movement of the abrasive material based on this amount of grinding. There is a limit to the creation of highly accurate free-form surfaces with grinding using a loop-controlled grinding machine.

The purpose of the present invention is to overcome the problems of the prior art and to process workpieces such as press molds with three-dimensional free-form surfaces that have already undergone predetermined NC machining without relying on skilled work. A processing method in which the measured value of a free-form surface is compared with a preset reference value of a geometric quantity, a certain grinding machine, a grinding range, etc. are determined based on the comparison result, and automatic grinding is performed by the grinding machine. Furthermore, there is a processing method in which simple machining is performed to determine the accurate grinding range and grinding conditions that suit the complex shape, and then the grinding machine automatically grinds. A processing method that enables independent and highly accurate automatic grinding. Grinding is performed from a computer using a procedure that is consistent with on-site work, in which the amount of grinding is measured in the middle of grinding and the amount of movement of the abrasive material is corrected based on this amount of grinding. To provide a method for processing a workpiece such as a press die using a grinding machine, which can create a highly accurate free-form surface by modifying a command signal to the machine and repeating grinding according to the command. It is.

In order to achieve this objective, the present invention measures the free-form surface shape of a workpiece such as a press mold using a three-dimensional measuring machine using the three-dimensional coordinate values that serve as a reference for each measurement point and the surface normal vector at that point. Measure directly, send the signal of the measured value to the computer, and the computer compares this measured value with the three-dimensional coordinate value, which is the standard of the measurement coordinate set in advance, in the plane normal vector direction at that point, The difference value, which is the difference between the reference value of the three-dimensional coordinate value and the above measured value, is determined, and in this way, the difference value in the surface normal direction of each measurement point for the entire curved surface is determined, and these difference values are used as the basis. Regarding free-form surfaces,
Measurement points with a difference value larger than a specified certain value are detected as targets, and the measurement points are classified by width value according to the width value of the difference value set separately in the computer, and the distribution calculation is performed. The distribution area is determined as the grinding range, and the minimum value of the width values for which the distribution calculation was performed is determined as the amount of grinding in that range. A feature of the present invention is that command signals for the amount of grinding and the grinding range determined in this manner are sent from the computer to the grinding machine, and the workpiece is automatically ground by the grinding machine.

Furthermore, the present invention provides command signals for the grinding amount and grinding range determined according to the first aspect of the invention from a computer to a simple measuring machine equipped with a machining drill or scribing needle instead of the measuring probe of the coordinate measuring machine. It is sent to a processing machine, and this simple processing machine measures multiple points predetermined according to the curved surface condition of the workpiece within the range of measurement points with a difference value greater than a certain value specified for the workpiece. A hole is drilled to the specified dimension value relative to the reference value, a reference surface is shown that indicates the desired curved surface shape to be ground by this processing, and a new grinding machine is taught to the grinding machine based on the result of this simple processing. The range is sent to the computer. The computer takes in the data of the grinding range transmitted from the simple processing machine via the line, and stores it together with separately determined parameters such as the amount of grinding. Then, command signals for grinding conditions such as grinding pressure and number of grinding repetitions determined by the computer based on this new teaching information are sent to the grinding machine, and the workpiece is automatically ground by the grinding machine.

Furthermore, the present invention teaches the grinding range and grinding method of the workpiece to the controller of the grinding machine based on the information from the simple processing machine taught to the computer by the second invention, and based on this teaching information. Predetermined operating parameters such as the material of the object to be ground, the material of the grinding material, the amount of grinding per unit, the takeoff and landing method at the start and end of grinding are set in the controller of the grinding machine, and the grinding machine is disconnected from the computer and the grinding machine is operated. The machine is characterized by automatically grinding the workpiece by operating the grinder.

Furthermore, in the first aspect of the present invention, when sending the grinding range and grinding amount from the computer to the grinding machine, each measurement point of the workpiece that has already been ground by the grinding machine is used as a reference tertiary measurement. Original coordinate values and
Using the surface normal vector at that point, measure again perpendicularly to the surface using a coordinate measuring machine, and compare this measured value with the three-dimensional coordinate value, which is the reference of the measurement coordinates set in advance, in the direction of the surface normal vector at that point. It is characterized in that the comparison is made again and the above-mentioned command signal sent from the computer to the grinding machine is modified in accordance with the comparison result.

Next, the operation of the present invention will be explained.

According to the present invention, the free-form surface shape of a workpiece such as a press mold is determined by a movement path determined using three-dimensional coordinate values serving as a reference for each measurement point set in a computer and a surface normal vector at that point. The coordinate measuring machine is commanded to measure perpendicular to the surface, and the signal of the measured value is sent to the computer, and the computer calculates the measured value and the three-dimensional coordinate value that is the standard of the measurement coordinate set in advance. are compared in the direction of the surface normal vector at that point, and the difference value, which is the difference between the reference value of the three-dimensional coordinate value and the above measured value, is calculated. In this way, the surface normal of each measurement point for the entire curved surface is calculated. Calculate the difference values in the vector direction, use the crosshair cursor to indicate the approximate range on the graphic display displaying the color difference values based on these difference values, and then display the free-form surface included in the approximate range. In order to exclude points that are not to be ground within the range, the measurement points with a difference value greater than a certain value than the specified reference value are detected, and the difference value set separately in the computer is set to a certain unit height from the reference value. According to the divided width values, the above measurement points are classified for each width value, a distribution calculation is performed, the distribution area is determined as the grinding range, and the minimum value of the above width values for which the distribution calculation was performed is set as the range. Determined as the amount of grinding. Command signals for the grinding amount and grinding range determined in this manner are sent from the computer to the grinding machine, and the workpiece is automatically ground by the grinding machine.

Furthermore, according to the present invention, the free-form surface shape of a workpiece such as a press mold is determined by a movement path determined using three-dimensional coordinate values serving as a reference for each measurement point set in a computer and a surface normal vector at that point. The coordinate measuring machine commands the three-dimensional measuring machine to measure perpendicularly to the surface, sends the measurement signal to the computer, and the computer compares this measured value with the three-dimensional coordinate value that is the standard of the measurement coordinate set in advance. are compared in the direction of the surface normal vector at that point, and the difference value, which is the difference between the reference value of the three-dimensional coordinate value and the above measured value, is calculated. In this way, the surface normal direction of each measurement point for the entire curved surface is calculated. Find the difference values at In order to exclude points that are not to be ground, measurement points with a difference value greater than a certain value than the specified standard value are detected, and the difference value set separately in the computer is divided into a certain unit height from the standard value. The above measurement points are classified according to the width value, the distribution is calculated, and the distribution area is determined as the grinding range,
The minimum value of the width values for which the distribution calculation was performed is determined as the amount of grinding in that range.

The command signals for the amount of grinding and the grinding range determined in this way are sent from the computer to the measuring probe of the coordinate measuring machine, in order to reduce setup time and to use the same origin. It is sent to a simple processing machine equipped with a drill and a scribing needle, and this simple processing machine calculates the curved surface state of the workpiece in advance for the measurement points with a difference value greater than a specified value on the workpiece. It is possible to have the operator perform the drilling process to the depth of the specified dimension value at multiple reference points determined according to the process, and to present the reference surface to the operator that indicates the target curved surface shape to be ground by drilling this simple process. Yes (see Figure 10). The new grinding range taught to the grinding machine based on the result of this simple machining is sent to the computer.

In order for the grinding machine to teach the computer the new grinding range of the workpiece, the computer incorporates the data of the new grinding range transmitted from the grinding machine via the line, and inputs the separately specified parameters such as the grinding amount. remember with. Then, the computer sends command signals for grinding conditions such as the grinding pressure and the number of repetitions of grinding determined by the computer based on this new teaching information to the grinding machine, and the grinding machine automatically grinds the workpiece.

Furthermore, according to the present invention, the free-form surface shape of a workpiece such as a press mold is determined by a movement path determined using three-dimensional coordinate values serving as a reference for each measurement point set in a computer and a surface normal vector at that point. The coordinate measuring machine commands the three-dimensional measuring machine to measure perpendicularly to the surface, sends the measurement signal to the computer, and the computer compares this measured value with the three-dimensional coordinate value that is the standard of the measurement coordinate set in advance. are compared in the surface normal vector direction at that point, and the difference value, which is the difference between the reference value of the three-dimensional coordinate value and the above measured value, is calculated. In this way, the surface normal direction of each measurement point is calculated for the entire curved surface. Find the difference values at , indicate the approximate range with the crosshair cursor on the graphic display where the color difference values are displayed, and
In order to exclude points that are not to be ground within the range of the free-form surface included in this approximate range, the measurement points with a difference value larger than a specified reference value by a certain value or more are detected as targets,
Separately, the difference value set in the computer classifies the above measurement points according to the width value divided into fixed unit heights from the reference value, calculates the distribution, and grinds the distribution area. The minimum value of the width values determined as a range and subjected to distribution calculation is determined as the amount of grinding in that range. And the determined amount of grinding,
The command signal for the grinding range is transmitted from the computer to the above-mentioned three-dimensional measuring machine.Instead of the measurement probe of the three-dimensional measuring machine, a simple machine equipped with a drill and scribing needle for machining is used to reduce setup time and to use the same origin. The simple processing machine sends the workpiece to a plurality of reference points predetermined according to the curved surface condition for the measurement points of the difference value above a certain value specified for the workpiece. This simple drilling allows the operator to be presented with a reference surface indicating the desired curved surface shape to be ground (see FIG. 10). The new grinding range taught to the grinding machine based on the result of this simple machining is sent to the computer.

In this way, the new grinding range and grinding method of the workpiece taught by the grinding machine are sent to the grinding machine controller, and the grinding machine controller informs the grinding machine of the material of the workpiece, the material of the abrasive material, and the amount of grinding per unit. By setting predetermined operating parameters such as the amount of grinding, the start and end of grinding, and the separation method, the grinding machine is disconnected from the commands from the computer and only the grinding machine is operated, so that the workpiece is automatically ground by the grinding machine.

Furthermore, according to the present invention, the free-form surface shape of a workpiece such as a press mold is determined by a movement path determined using three-dimensional coordinate values serving as a reference for each measurement point set in a computer and a surface normal vector at that point. The coordinate measuring machine commands the three-dimensional measuring machine to measure perpendicularly to the surface, sends the measurement signal to the computer, and the computer compares this measured value with the three-dimensional coordinate value that is the standard of the measurement coordinate set in advance. are compared in the direction of the surface normal vector at that point, and the difference value, which is the difference between the reference value of the three-dimensional coordinate value and the above measured value, is calculated. In this way, the surface normal direction of each measurement point for the entire curved surface is calculated. Find the difference values at In order to exclude points that are not to be ground, measurement points with a difference value greater than a certain value than the specified standard value are detected, and the difference value set separately in the computer is divided into a certain unit height from the standard value. The above measurement points are classified according to the width value, the distribution is calculated, and the distribution area is determined as the grinding range,
The minimum value of the width values for which the distribution calculation was performed is determined as the amount of grinding in that range. In a processing method such as a press die, in which command signals for the amount of grinding and grinding range determined in this way are sent from a computer to a grinding machine, and the workpiece is automatically ground by the grinding machine, after the workpiece has been ground by the grinding machine. Using the surface normal vector at that point, which serves as the reference for each measurement point of the workpiece, measure again perpendicularly to the surface with the coordinate measuring machine as described above, and then use this measurement value and the preset measurement coordinate reference. The three-dimensional coordinate values are again compared in the surface normal vector direction at that point, and the command signal sent from the computer to the grinding machine is modified in accordance with the comparison result.

Next, embodiments of the present invention will be described with reference to the drawings.

Figure 1 is a configuration diagram of the entire system 1, where the three-dimensional measuring machine 2 also serves as a simple NC (numerical control) processing machine.
Measurement of geometric quantities, that is, three-dimensional coordinate values, of the press die 3 as a workpiece that has already undergone the specified NC machining, and simple machining such as scribing or standard groove machining of the press die 3. do fast
It has an NC controller 4. The automatic grinding robot 5 has a high-speed NC controller 6 and performs highly accurate grinding (polishing) of the press mold 3. High speed NC controller 4,
6 is connected online to a dedicated electronic computer 8 via a microcomputer 7. In addition, high-speed NC
A switch 9 is provided between the controller 6 and the microcomputer 7, and by setting the switch 9 to the OFF position, the automatic grinding robot 5 is operated not online but disconnected from the microcomputer 7 (stand-alone system). can be done. The microcomputer 7 has a data file 13 with a large capacity storage area, and a dedicated electronic computer 8.
is equipped with a database information file 14 that stores information that serves as a reference for measurement and analysis.

As described above, since the microcomputer 7 and the dedicated computer 8 are provided, on-site work can be carried out quickly. Note that depending on the capabilities of the computers, they may be combined into one computer. The data file 13 is a database storage area 13a
and a measurement data storage area 13b.
The microcomputer 7 includes a color television 1 for controlling the entire system 1 and displaying analysis results.
5, and a color plotter (printer) 16 for storing analysis results.

Figure 2 is a flowchart of a program that measures and analyzes the curved surface of the press die 3 that has undergone a predetermined amount of NC machining. A brief description of each step is as follows.

Step 21: Transfer the database information to the data file Step 22: Instruct the coordinate measuring machine to perform measurement 〃 23: Import the measured values 〃 24: Write the measured values to the data file 〃 25: Is it possible to compare on a microcomputer? 〃 26: Comparison of comparison value and measured value (microcomputer) 〃 27: Send measured value to dedicated computer 〃 28: Calculate reference value corresponding to measured value (dedicated computer) 〃 29: Calculate to microcomputer Send the results 〃 30: Display the arithmetic difference on the color TV based on the comparison results 〃 31: Are there any measurement points left in the range? 〃 32: Has the measurement of the entire range been completed? 33: Do you want to record the screen? 〃 34: Record the screen on a printer (printer) 〃 35: Do you want to perform scribing processing? 〃 36: Calculate and output scribing information based on the measurement results 〃 37: Execute scribing In step 21, operate the keyboard of the color television 15 to input the database information in the database information file 14 corresponding to the press mold 3 into a unique format. The data structure (storage format) is changed and transferred as a reference value to the database storage area 13a in the data file 13 via the microcomputer 7. In step 22, the coordinate measuring machine 2 measures the geometric quantity (for example, the actual Z coordinate value) of the position to be measured (the position to be measured is determined according to the X and Y coordinates, for example). instruct. In step 23, the measured values from the coordinate measuring machine 2, that is, the three-dimensional coordinate values, are taken in, and in step 24, the measured values are written into the measured data storage area 13b of the data file 13. In step 25, the microcomputer 7 determines whether or not this measured value can be compared, that is, the reference value corresponding to this measured value, that is, the three-dimensional coordinate value on the mathematical model representing the curved surface shape, is determined by the surface normal vector as database information. Determine whether it is in the storage area 13a,
If the determination result is positive, the process proceeds to step 26; if not, the process proceeds to 27. In step 26, the measured values are transferred from the database information storage area 13a and the measured data storage area 13b to the microcomputer 7, and the corresponding reference values and measured values are compared. In step 27, the measured value is transmitted to the dedicated computer 8. In step 28, the dedicated electronic computer 8
In the step, a reference value corresponding to the transmitted measurement value is calculated using the database information in the database information file 14. At step 29, the results of the calculation at step 28 are sent to the microcomputer 7. If the data in the database area 13a in the data file 13 is insufficient in this way,
If the data in the measurement data storage area 13b is insufficient, the reference value corresponding to the measurement data in the measurement data storage area 13b is stored in the database information file 14.
Calculations are made using the data in the microcomputer 15.
and send it to for comparative analysis. In step 30, based on the comparison result, the difference between the measured value and the reference value is displayed on the color television 15 using different colors. That is, the difference between the two is displayed in different colors depending on the size. In step 31, it is determined whether or not there are still locations to be measured in the measurement range corresponding to the data in the database information storage area 13a, and if the determination result is negative, the process proceeds to step 32.
If it is positive, the process returns to step 22. In step 32, it is determined whether or not the measurement of the entire range of the press die 3 has been completed. If the determination result is positive, the process proceeds to step 33; if not, the process returns to step 21. In step 32, it is determined whether or not the screen of the color television 15 is to be stored, and if the determination result is positive, the process proceeds to step 34.
If not, proceed to step 35. Step 3
4, the screen of the color television 15 is displayed on the color plotter (printer) 16. In step 35, it is determined whether or not to scribe the press die 3. If the determination result is positive, the process proceeds to step 36, and if not, the program is terminated. In step 36, information on the amount and range of markings is calculated and sent to the three-dimensional measuring machine 2. In step 37, coordinate measuring machine 2
The press mold 3 is marked with. The 3D measuring machine 2 also serves as a simple 3D NC processing machine.
Deep scribing (drilling), reference groove machining, contour line marking (connecting points of the same height with a line), ridgeline scribing (drawing a line along the ridgeline), profile scribing (outline as an external shape) Perform simple NC processing such as (pulling) on press die 3.

FIG. 3 is a program flowchart for operating the automatic grinding robot 5 online. A schematic description of each step is as follows.

Step 41: Measuring the geometrical quantities of the press die;
Analysis 〃 42: Store the analysis results in the microcomputer 〃 43: Command the grinding conditions 〃 44: Calculate the grinding range and amount of grinding on the microcomputer 〃 45: Calculate the grinding work information on the microcomputer 〃 46: To the automatic grinding robot Command the grinding work 〃 47: Is the grinding completed? In step 41, the geometrical quantities of the press die 3 are measured and analyzed. The details of the measurement and analysis are as shown in the flowchart in Figure 2. Steps 36 and 37 of the flowchart in Figure 2 are canceled and simplified steps are taken.
The press die 3 is not marked by the three-dimensional measuring machine 2 which also serves as an NC processing machine. Step 42
Now, the analysis result in step 41 is stored in the microcomputer 7. In step 43, the grinding conditions are commanded from the keyboard of the color television 15. The grinding conditions relate to operating parameters when operating the automatic grinding robot 5, such as the direction of grinding movement of the abrasive material, the number of times of grinding, etc. In step 44, the microcomputer 7 calculates the grinding range and grinding amount of the press mold 3 based on the analysis results stored in step 42.

In step 45, the microcomputer 7 calculates grinding work information for the automatic grinding robot 5 based on the grinding range and grinding amount calculated in step 44. Grinding work information is a command that specifies the specific grinding movement of the abrasive material of the automatic grinding robot 5, and when the abrasive material repeats a predetermined grinding movement, it includes the positions of both ends of the grinding movement, the path, and the contact pressure. etc. In step 46, a command signal is sent to the automatic grinding robot 5 based on the grinding work information in step 45, and the automatic grinding robot 5 moves the press mold 3.
grinding machine. In step 47, it is determined whether all the grinding of the press mold 3 has been completed, and if the determination result is positive, the program is terminated, and if not, the process returns to step 41.

The calculation process of the grinding work information in step 45 of FIG. 3 will be described in detail.

The calculation of the grinding operation information in step 45 is as follows:
Based on the results of this analysis, grinding is performed in order from the parts with the largest differences based on parameters such as the shape of the grinding (abrasive) material, the amount of grinding (polishing) per unit, and the contact pressure. Specifically, the part with the largest difference in Figure 7 is "No.
3, the grinding path is calculated by considering the above-mentioned parameters.

Next, the route calculation is performed in the same way for the portion including "No. 3" and "No. 2". In this way, processing is performed down to the part with the smallest difference.

Also, calculate the grinding path for each surface to avoid disturbing the boundaries. A part of the calculated grinding path is shown in FIG.

The grinding method in this case is reciprocating or one-way grinding within the grinding range depending on the operating parameters and grinding conditions [Figure 9a
or one-way grinding, b indicates reciprocating grinding, and c indicates cross-reciprocating grinding]. In addition, in order to avoid changing the characteristics of the grinding surface, when the abrasive material comes into contact with the workpiece, or how it separates from the workpiece, it is determined whether vertical takeoff and landing or smooth takeoff and landing (see Figure 9b).

FIG. 4 is a flowchart of a program in which the automatic grinding robot 5 teaches the microcomputer 7 the grinding range of the press die 3 and then operates the automatic grinding robot 5 online. A schematic description of each step is as follows.

Step 51: Measuring the geometrical quantities of the press mold;
Analysis 〃 52: Command the scribing work to the coordinate measuring machine 〃 53: Teach the grinding range of the press die from the automatic grinding robot to the microcomputer 〃 54: Command the grinding conditions 〃 55: Calculate grinding work information on the microcomputer 〃 56: Command the automatic grinding robot to perform grinding work 〃 57: Has the grinding been completed? In step 51, the geometrical quantities of the press die 3 are measured and analyzed, and based on this analysis result, the process is carried out in step 5.
In step 2, a command signal is sent to the three-dimensional measuring machine 2 to mark the press mold 3. For scribing, step 52
This is done to indicate the grinding range on the press mold 3 based on the analysis result, and the inside surrounded by the marking lines is defined as the grinding range. The details of the measurement, analysis, and marking in steps 51 and 52 are as shown in the flowchart of FIG. In step 53,
The grinding material serving as the head of the automatic grinding robot 5 is traced along the grinding boundary line of the press die to teach the microcomputer 7 the grinding range. By making the grinding boundary line different from the scribing line, the actual grinding range can be made larger than the grinding range calculated by the microcomputer 7. Steps 54, 55, 56, 57
are the same as steps 43, 45, 46, and 47 in FIG. 3, and their explanation will be omitted. Since the measurement and analysis results in step 51 are displayed as marking lines on the press die 3, there is no need to store the analysis results in the microcomputer 7 as in step 42 of FIG.

FIG. 5 is a flowchart of a program for disconnecting the automatic grinding robot 5 from the microcomputer 7 and operating it. A schematic description of each step is as follows.

Step 61: Measuring the geometrical quantities of the press mold;
Analysis 〃 62: Command the scribing work to the coordinate measuring machine 〃 63: Teach the grinding range of the press die from the automatic grinding robot to the microcomputer 〃 64: Command the grinding conditions to the controller of the automatic grinding robot 〃 65: The controller operates the automatic grinding robot. 〃 66: Is the grinding completed? Steps 61 and 62 are steps 51 and 62 in FIG.
It is similar to 52. In step 63, the grinding material serving as the head of the grinding robot 5 is moved along a predetermined trajectory on the press die 3 to teach the grinding range and grinding method.
In step 64, the grinding conditions such as the number of grinding times are directly instructed to the grinding robot 5, and other grinding conditions such as the grinding pressure are set by the controller 6. These grinding conditions become the operating parameters of the grinding machine. In step 65, the microcomputer 7
The automatic grinding robot 5 is operated. Step 66 is similar to step 47 of FIG. In steps 63, 64, and 65, switch 9 is placed in the off position.

FIG. 6 is a flowchart of a program for automatically grinding a press die while measuring the amount of grinding. A brief description of each step is as follows.

Step 71: Measuring the geometric quantities of the press die;
Analysis 〃 72: Command the grinding conditions 〃 73: Calculate the grinding range and grinding amount on the microcomputer 〃 74: Calculate the grinding work information on the microcomputer 〃 75: Command the grinding work to the automatic grinding robot 〃 76: Calculate the grinding area measurement of geometric quantities,
Analysis 〃 77: Has the grinding at the location been completed? 〃 78: Has the grinding of all parts within the range been completed? 〃 79: Has the grinding of all the grinding ranges of the press mold been completed? Steps 71, 72, 73, 74, and 75 correspond to steps 41 and 4 in the flowchart of FIG. 3, respectively.
Same as 3, 44, 45, 46. Step 7
In step 6, the geometrical quantities of the part being ground are measured and analyzed using the three-dimensional measuring machine 2 without contact.
In step 77, the geometric amount of this grinding point is compared with a reference value to determine whether or not the grinding of this grinding point has been completed.If the determination result is positive, the process advances to step 78. If so, return to step 75.
In step 78, it is determined whether or not the grinding of all parts in the area being ground has been completed. If the result of the determination is positive, the process proceeds to step 79, and if not, the process returns to step 73. In step 79, it is determined whether or not the grinding of all the grinding ranges of the press die has been completed, and if the determination result is positive, the program is terminated.
If not, the process returns to step 71. Since the grinding is carried out while detecting the actual grinding amount by the automatic grinding robot 5 in step 76, the grinding accuracy can be greatly improved.

As described above, according to the present invention, the geometrical quantity of the workpiece, that is, each measurement point, is calculated using the three-dimensional coordinate values and surface normal vector data of each measurement point on the mathematical model representing the curved surface shape of the press die. The shape of the entire curved surface can be determined by measuring the three-dimensional coordinate values of the surface perpendicularly with a three-dimensional measuring machine and comparing the measured values with a reference value (three-dimensional coordinate values) having a surface normal vector in the surface normal vector direction. It can be accurately grasped, and the measured value is constantly compared with a reference value (three-dimensional coordinate value) with a preset surface normal vector.
Based on this comparison result, the difference between the measured value and the reference value in the surface normal direction of the entire curved surface, that is, the difference value, is calculated, and the command signal for the calculated grinding amount and grinding range is constantly fed back to the grinding machine for automatic grinding. From there, commands are sent that follow the on-site work procedure for three-dimensional free-form surfaces such as press dies, etc., further improving grinding accuracy. Further, since the present invention performs automatic grinding while correcting the command signal using various operating parameters, it is possible to achieve grinding accuracy equivalent to or higher than grinding work performed by a skilled worker when grinding a three-dimensional free-form surface such as a press mold.

In particular, the first invention enables shape measurement and shape grinding through numerical control, improves grinding accuracy, and further improves work efficiency. Also the second
In the second invention, by performing simple machining, it is possible to provide an accurate grinding range and grinding method that is suitable for complex shapes. Further, in the third aspect of the invention, by setting various operating parameters in the controller of the grinding machine based on the results of simple machining, accurate grinding can be performed even when the machine is disconnected from the computer. In addition, in the fourth invention, re-measurement is carried out in the middle of the grinding process.
By repeating reanalysis, accurate grinding can be achieved even if the grinding information changes, and the cycle from measurement to grinding can be sped up.

In addition, in the present invention, the spotting model is used as a database (reference value), the spotting press is used as measurement data from a coordinate measuring machine, and the red hit test is performed on a computer by comparing the measured value with the reference value, or by comparing the measured value with the reference value on a computer, or by using the measurement data based on the comparison result. For simple processing of processed products,
Grinding work by skilled workers can be replaced with automatic grinding work by an automatic grinder, and quantitative grinding is performed based on a database, further improving the quality of press molds.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the system configuration of the present invention,
Figure 2 is a flowchart of a program that measures and analyzes the geometrical quantities of a press die; Figure 3;
Figures 4, 5, and 6 are flowcharts of the embodiments of the present invention, Figure 7 is a diagram of the difference layout after analysis, Figure 8 is a diagram of the grinding path, and Figure 9 is an explanatory diagram of the grinding method. , FIG. 10 is an explanatory diagram of simple processing. 2... Coordinate measuring machine, 3... Press mold, 4... Controller, 5... Automatic grinding robot, 6... Controller, 7...
Microcomputer, 8... Dedicated electronic computer, 1
3...data file, 14...database information file, 15...color television, 16...color plotter.

Claims (1)

[Claims] 1. The free-form surface shape of a workpiece such as a press mold is measured perpendicularly to the surface using a three-dimensional coordinate value serving as a reference for each measurement point and the surface normal vector at that point. , the signal of the measured value is sent to the computer, and the computer compares this measured value with the three-dimensional coordinate value, which is the reference of the measurement coordinate set in advance, in the surface normal vector direction at that point, and calculates the three-dimensional coordinate value. Find the difference value that is the difference between the reference value and the above measured value, and in this way find the difference value in the surface normal direction of each measurement point for the entire curved surface, and based on these difference values, A method for processing press molds, etc., characterized by determining the amount of grinding and grinding range for measurement points with large difference values, sending command signals from a computer to a grinding machine, and automatically grinding the workpiece by the grinding machine. . 2. Measure the free-form surface shape of a workpiece such as a press die perpendicularly to the surface using a three-dimensional coordinate value that serves as a reference for each measurement point and the surface normal vector at that point, and then use a three-dimensional measuring machine to measure the shape of the free-form surface of the workpiece, such as a press mold, perpendicularly to the surface. is sent to the computer, and the computer compares this measured value with the three-dimensional coordinate value, which is the standard of the measurement coordinate set in advance, in the surface normal vector direction at that point, and compares the reference value of the three-dimensional coordinate value with the above-mentioned measurement value. In this way, the difference value in the surface normal direction of each measurement point for the entire curved surface is determined, and based on these difference values, measurement points with a difference value larger than a certain value are determined. The amount of grinding and the grinding range are determined, the command signal is sent from the computer to the simple processing machine, the simple processing machine performs simple processing on the workpiece, and the grinding machine gives instructions based on the results of this simple processing. A new grinding range is sent to the computer, and command signals for grinding conditions such as grinding pressure determined by the computer based on this new information are sent from the computer to the grinding machine, and the grinding machine automatically grinds the workpiece. A processing method for press molds etc. characterized by 3. Measure the free-form surface shape of a workpiece such as a press die perpendicularly to the surface using a three-dimensional coordinate value that serves as a reference for each measurement point and the surface normal vector at that point, and send a signal of the measured value. is sent to the computer, and the computer compares this measured value with the three-dimensional coordinate value, which is the standard of the measurement coordinate set in advance, in the surface normal vector direction at that point, and compares the reference value of the three-dimensional coordinate value with the above-mentioned measurement value. In this way, the difference value in the surface normal direction of each measurement point for the entire curved surface is determined, and based on these difference values, measurement points with a difference value larger than a certain value are determined. The amount of grinding and the grinding range are determined, the command signal is sent from the computer to the simple processing machine, the simple processing machine performs simple processing on the workpiece, and the grinding machine gives instructions based on the results of this simple processing. The new grinding range and grinding method are sent to the grinding machine controller, and based on this new information, the grinding machine controller sets predetermined operating parameters, disconnecting the grinding machine from the computer and operating only the grinding machine. A processing method for press molds, etc., characterized by automatically grinding a workpiece by grinding the workpiece. 4. Measure the free-form surface shape of a workpiece such as a press die perpendicularly to the surface using a three-dimensional coordinate value and the surface normal vector at that point at each measurement point, and use the signal of the measured value. is sent to the computer, and the computer compares this measured value with the three-dimensional coordinate value, which is the standard of the measurement coordinate set in advance, in the surface normal vector direction at that point, and compares the reference value of the three-dimensional coordinate value with the above-mentioned measurement value. In this way, the difference value in the surface normal direction of each measurement point for the entire curved surface is determined, and based on these difference values, measurement points with a difference value larger than a certain value are determined. In processing methods such as press molds, in which the grinding amount and grinding range are determined, and the command signal is sent from a computer to the grinding machine, the workpiece is automatically ground by the grinding machine. Using the three-dimensional coordinate value that serves as the reference for each measurement point and the surface normal vector at that point, measure again perpendicular to the surface using a three-dimensional measuring machine. A method for machining a press mold, etc., characterized in that the original coordinate values are compared again in the plane normal vector direction at that point, and the above-mentioned command signal sent from a computer to a grinding machine is modified according to the comparison result.