Machining state prediction device and machining control device

Abstract

A machining state prediction device according to the present disclosure includes: a program analysis unit for analyzing command blocks upon reading a machining program for controlling operation of a thermal cutting machine; a machining path determination unit for determining a machining path of the thermal cutting machine on the basis of the analyzed command blocks; a machining condition determination unit for determining machining conditions of the thermal cutting machine on the basis of the command blocks; a condition change section determination unit for determining condition change sections, where machining conditions are changed, on the machining path on the basis of the determined machining path and machining conditions; a correction value determination unit for determining condition correction values in the condition change sections; a condition correction processing unit for determining machining condition changes in the condition change sections on the basis of the condition correction values; and a machining state output unit for outputting a prediction result of the machining state of the entire machining path on which the machining condition changes are reflected.

Description

Machining state prediction device and machining control device

[0001] The present disclosure relates to a machining state prediction device and a machining control device.

[0002] For example, thermal cutting techniques such as gas cutting, laser cutting, plasma cutting, and electron beam cutting are known as techniques for cutting workpieces such as metal plates. In thermal cutting techniques, thermal energy from a heat source is irradiated onto the workpiece to melt it, and the melted area is then removed to form a cut groove in the workpiece.

[0003] To explain such thermal cutting processing technology using laser cutting as an example, a laser beam is irradiated onto a workpiece to form a molten pool that penetrates the workpiece in the thickness direction, and this is then removed by jetting assist gas or the like while moving the workpiece along a predetermined processing path to form a continuous cut groove (cut line). For example, in the case of laser cutting, the laser beam as thermal energy irradiated onto the workpiece has the property of converging at a focal position, so by adjusting this focal position relative to the workpiece surface, the degree of convergence of the laser beam can be changed and the spot diameter of the molten pool can be appropriately adjusted.

[0004] As an example of such a laser processing machine, for example, Patent Document 1 discloses a laser processing machine provided with: a transient speed correction data calculation means for calculating transient speed correction data based on a workpiece cutting speed specified in a processing program stored in a first memory means and a beam diameter correction value in a processing condition file stored in a second memory means; an actual speed calculation means for detecting and calculating the actual speed of the workpiece cutting; a correction amount calculation means for calculating a correction amount based on the calculated transient speed correction data and the actual speed of the workpiece cutting; and a correction execution means for shifting the processing path in a direction perpendicular to the cutting direction based on the calculated correction amount. This laser processing machine is said to be able to reduce cutting shape errors when accelerating or decelerating the workpiece.

[0005] Japanese Patent Application Publication No. 4-86903

[0006] However, in the case where the machining path changes direction at a bending point, the machining speed decreases near the bending point, and therefore a laser machining device capable of reducing the cutting shape error during acceleration and deceleration is used. However, the control method of the conventional laser machining device detects the actual speed during actual machining and calculates the correction amount based on the difference between the actual speed and the assumed speed specified in the machining program. Therefore, the correction can only be performed while the machining is actually being performed, and there is a problem that the calculation of the correction amount after measuring the actual speed causes a delay (control delay) before the actual correction operation is performed.

[0007] Given these circumstances, there is a demand for processing control technology that can control processing of thermal cutting machines while eliminating control delays caused by the operation of measuring and correcting the actual speed during processing.

[0008] A machining state prediction device according to one aspect of the present disclosure includes a program analysis unit that reads a machining program that controls the operation of a thermal cutting machine and analyzes a command block; a machining path determination unit that determines a machining path for the thermal cutting machine based on the analyzed command block; a machining condition determination unit that determines machining conditions for the thermal cutting machine based on the analyzed command block; a condition change section determination unit that determines a condition change section on the machining path where the machining conditions are changed based on the determined machining path and machining conditions; a correction value determination unit that determines a condition correction value in the condition change section; a condition correction processing unit that determines changed machining conditions in the condition change section based on the condition correction value; and a machining state output unit that outputs a predicted result of the machining state for the entire machining path reflecting the changed machining conditions.

[0009] In addition, a processing control device according to another aspect of the present disclosure includes a program analysis unit that reads a processing program that controls the operation of a thermal cutting machine and analyzes command blocks; a processing path determination unit that determines a processing path for the thermal cutting machine based on the analyzed command blocks; a processing condition determination unit that determines processing conditions for the thermal cutting machine based on the analyzed command blocks; a condition change section determination unit that determines a condition change section on the processing path where the processing conditions are changed based on the determined processing path and processing conditions; a correction value determination unit that determines a condition correction value in the condition change section; a condition correction processing unit that determines changed processing conditions in the condition change section based on the condition correction value; and a main control unit that outputs processing control commands for the entire processing path based on the processing conditions that reflect the changed processing conditions.

[0010] 10 is a block diagram showing the configuration of a laser machining apparatus including a display device and a machining control device according to the first embodiment. FIG. 11 is a top view showing an arrangement of a workpiece and a machining path simulated by the machining prediction device according to the first embodiment. FIG. 12 is a graph showing an example of information of changed machining conditions. FIG. 13 is an example of a two-dimensional image showing a machining state when machining is performed based on the changed machining conditions shown in FIG. 3. FIG. 14 is a two-dimensional image showing an example of a prediction result of a kerf groove after cutting. FIG. 15 is a top view showing an arrangement of a workpiece and another machining path simulated by the machining prediction device according to the first embodiment. FIG. 16 is an example of a two-dimensional image showing a machining state when machining is performed on the other machining path shown in FIG. 6. FIG. 17 is a block diagram showing the configuration of a machining state prediction device according to a first modified example. FIG. 18 is a top view showing an arrangement of a workpiece and a machining path simulated by the machining prediction device according to the second modified example. FIG. 19 is a graph showing an example of information of changed machining conditions in the second modified example. FIG. 19 is an example of a two-dimensional image showing a machining state when machining is performed based on the changed machining conditions shown in FIG. 10. 14 is an example of a two-dimensional image showing the machining state when machining is performed based on the changed machining conditions shown in FIG. 13. FIG. 15 is a two-dimensional image showing an example of a prediction result of a kerf groove after cutting based on the changed machining conditions shown in FIG. 13. FIG. 16 is a top view showing the arrangement of a workpiece and a machining path simulated by a machining prediction device according to a third modified example. FIG. 17 is a graph showing an example of information on changed machining conditions in the third modified example. FIG. 18 is an example of a two-dimensional image showing the machining state when machining is performed based on the changed machining conditions shown in FIG. 17. FIG. 19 is a two-dimensional image showing an example of a prediction result of a kerf groove after cutting based on the third modified example. FIG. 19 is a schematic diagram showing the overall configuration of a thermal cutting machine including a machining control device according to a second embodiment. FIG. 20 is a block diagram showing the configuration of a machining control device according to a second embodiment.

[0011] Hereinafter, an embodiment of a machining state prediction device and a machining control device having a function of predicting the machining state of a thermal cutting machine based on a machining program according to a representative example of the present disclosure will be described with reference to the drawings.

[0012] In this disclosure, "based on XX" means "based on at least XX," and includes cases where it is based on other elements in addition to XX. Furthermore, "based on XX" is not limited to cases where XX is used directly, but also includes cases where it is based on XX that has been calculated or processed. Here, "XX" means any element (for example, any information).

[0013] Furthermore, in this disclosure, a "thermal cutting machine" refers to a machine that applies thermal energy with a predetermined spot diameter to, for example, a metal workpiece (workpiece W) to form a melt spot on the workpiece W, and then continuously performs an operation of removing the melt spot along a predetermined processing path to form a cut groove in the workpiece W. Examples of such thermal cutting machines include gas processing machines, plasma processing machines, laser processing machines, electron beam processing machines, and ion beam processing machines, but the following description will be given of the case where a laser processing machine (laser processing device) is used.

[0014] First Embodiment FIG. 1 is a block diagram showing the configuration of a machining state prediction device according to a first embodiment, which is a representative example of the present disclosure.

[0015] 1, the machining state prediction device 100 according to the first embodiment includes, as an example, a main control unit 110, a program analysis unit 120, a machining path determination unit 130, a machining condition determination unit 132, a condition change section determination unit 134, a correction value determination unit 136, a condition correction processing unit 138, and a machining state output unit 140. This machining state prediction device 100 is configured to have a function of predicting the machining state of a thermal cutting machine based on a machining program.

[0016] The machining state predicting device 100 in the present disclosure is configured, for example, by a computer or the like including a processor, a CPU, or the like having the functions of each unit shown in Fig. 1. In this case, each component of the machining state predicting device 100 may also have a memory for temporarily storing information.

[0017] The main control unit 110 of the first embodiment controls the overall operation of the machining state prediction device 100, and has the function of connecting to peripheral devices and transmitting and receiving various signals. As an example, as shown in Figure 1, the main control unit 110 reads a machining program that controls the operation of the thermal cutting machine from an external storage device or recording medium such as a database (not shown), sends it to the program analysis unit 120, and outputs the machining state prediction result received from the machining state output unit 140 as output data to an external display device.

[0018] As an example, the program analysis unit 120 receives a machining program from the main control unit 110, analyzes it, and determines what command blocks are included in the machining program. The program analysis unit 120 may have a function to temporarily store and save the loaded machining program and the determined command blocks. The program analysis unit 120 then sends information on the determined command blocks of the machining program to the machining path determination unit 130 and the machining condition determination unit 132.

[0019] The machining path determination unit 130 determines the machining path along which the thermal cutting machine operates, based on the information of the command block analyzed by the program analysis unit 120. Information on the determined machining path is sent to the condition change section determination unit 134.

[0020] The machining condition determination unit 132 determines the machining conditions for the machining that the thermal cutting machine will actually perform, based on the information in the command block analyzed by the program analysis unit 120. Information on the determined machining conditions is sent to the condition change section determination unit 134.

[0021] The condition-change section determination unit 134 associates the received machining path information with the machining condition information, determines which section of the machining path needs to have the machining conditions changed, and determines the condition-change section on the machining path where the machining conditions will be changed. The procedure by which the condition-change section determination unit 134 determines the condition-change section will be described later. The condition-change section determination unit 134 then sends information about the determined condition-change section to the correction value determination unit 136, along with the above-mentioned machining path and machining condition information.

[0022] The correction value determination unit 136 determines a condition correction value for the machining conditions in the condition change section based on the transmitted information on the machining conditions and the condition change section. As an example, the correction value determination unit 136 determines the condition correction value based on an arithmetic expression including various machining parameters described below. The correction value determination unit 136 then transmits information on the determined condition correction value to the condition correction processing unit 138 together with the information on the machining path, machining conditions, and condition change section described above.

[0023] The condition correction processing unit 138 determines the changed machining conditions in the condition change section based on the condition correction value sent. Then, the condition correction processing unit 138 sends information on the machining conditions obtained by changing the changed machining conditions in the condition change section in the machining path determined by the machining path determination unit 130 to the machining state output unit 140 together with information on the associated machining path.

[0024] The machining state output unit 140 creates output data of the predicted results of the machining state for the entire machining path that reflects the changed machining conditions based on the information on the machining path and machining conditions sent to it, and outputs the output data to the main control unit 110. Examples of the output data created by the machining state output unit 140 include two-dimensional image data that includes the machining path on the workpiece W and the machined cutting groove.

[0025] Next, an outline of the machining prediction operation executed by the machining state prediction device according to the first embodiment will be described with reference to FIGS.

[0026] Fig. 2 is a top view showing the arrangement of a workpiece and a machining path simulated by the machining prediction device according to the first embodiment. Fig. 3 is a graph showing an example of information on changed machining conditions. Fig. 4 is an example of a two-dimensional image showing a machining state when machining is performed based on the changed machining conditions shown in Fig. 3. Fig. 5 is a two-dimensional image showing an example of a prediction result of a kerf groove after cutting. Fig. 6 is a top view showing the arrangement of a workpiece and another machining path simulated by the machining prediction device according to the first embodiment. Fig. 7 is an example of a two-dimensional image showing a machining state when machining is performed on another machining path shown in Fig. 6.

[0027] As an example of a case where it is necessary to change the machining conditions when machining along a predetermined machining path, consider a case where cutting is started at a machining start point P1 along a linear machining path R1 on a workpiece W and completed and stopped at a machining end point P3, as shown in Figure 2. In such a case, after cutting is performed at a predetermined speed from the machining start point P1 on the machining path R1, it is preferable to slightly reduce the machining speed in the section after a predetermined midpoint P2 in order to reduce the load due to inertia on the machining device when machining is completed (i.e., stopped) at the machining end point P3.

[0028] More specifically, the condition change section determination unit 134 of the machining state prediction device 100 determines the position of the midpoint P2 for defining the condition change section CS for slightly reducing the machining speed, based on the information on the machining path and machining conditions determined by the machining path determination unit 130 and the machining condition determination unit 132. At this time, the position of the midpoint P2 is determined by appropriate calculation taking into consideration the rigidity of the entire machining device, the time required for the entire cutting process (takt time), etc.

[0029] Next, the correction value determination unit 136 of the machining state prediction device 100 determines the machining condition items to be changed in the condition change section CS and their correction values. In the case of the machining path R1 shown in Figure 2, as an example, the machining speed, which is one of the machining conditions in the condition change section CS, is reduced. The correction value for the machining speed at this time is determined using a known relational expression between the heat input per unit time and the molten pool diameter at a predetermined laser output, taking into account the material and thickness of the workpiece W.

[0030] If the processing conditions (such as the output power of the laser beam) from the processing start point P1 to the midpoint P2 are maintained in the condition change section CS after the midpoint P2, it will no longer be possible to form the same melt diameter (i.e., the width H of the kerf shown in FIG. 5) as before. Therefore, when the correction value determination unit 136 determines the correction value of the processing conditions, it is preferable to also reduce the laser output power of the laser beam in order to keep the predetermined width H of the kerf constant throughout the entire processing path R1.

[0031] Next, the condition correction processing unit 138 of the machining state prediction device 100 determines changed machining conditions for the entire machining path R1 in association with the machining positions, taking into consideration the correction values ​​of the machining conditions in the condition change section CS, as shown in Fig. 3 for example. Then, as described above, the condition correction processing unit 138 sends information on the changed machining conditions to the machining state output unit 140.

[0032] Next, the machining state output unit 140 of the machining state prediction device 100 generates output data predicting the machining state when cutting is actually performed based on the received information on the changed machining conditions. An example of this output data is a two-dimensional image simulating the molten pool PD1 and beam spots BS1 and BS2 of the laser beam relative to the machining path R1, as shown in Figure 4.

[0033] That is, with the predicted output data, cutting starts at the processing start point P1 under processing conditions of processing speed V1, laser beam spot BS1, and molten pool PD1. Then, at the midpoint P2, which is the start position of the condition change section CS where the heat capacity of the workpiece W changes, the processing conditions are changed to processing speed V2 and beam spot BS2, and cutting is continued until the processing end point P3.

[0034] The machining state output unit 140 can also create a two-dimensional image of the shape prediction result of the kerf groove CG on the workpiece W after cutting, as shown in Fig. 5, for example, in addition to the two-dimensional image shown in Fig. 4. In the example shown in Fig. 5, by adjusting both the machining speed and laser output in the condition change section CS, the width H of the kerf groove CG becomes uniform over the entire machining path R1.

[0035] 4 and 5 to the main control unit 110. Upon receiving this output data, the main control unit 110 can, for example, output the received output data to an external display device to display the prediction results.

[0036] The prediction of the machining state described above can also be applied to a case where cutting is performed to cut out the inside of a workpiece W along a circular machining path R1, as shown in Fig. 6. That is, when cutting is started at a machining start point P1 for the circular machining path R1 and finished and stopped at a machining end point P3, the prediction can also be performed in a case where the machining speed is reduced at an intermediate point P2 on the machining path R1.

[0037] In the case of such a machining path R1, the output data is predicted as shown in Figure 7. That is, at the machining start point P1, cutting is started under machining conditions of machining speed V1, laser beam spot BS1, and molten pool PD1, and machining continues along the circular machining path R1 under these machining conditions. Then, at the midpoint P2, which is the start position of the condition change section CS where the heat capacity of the workpiece W changes, the machining conditions are changed to machining speed V2 and beam spot BS2, and cutting is continued until it reaches the machining end point P3.

[0038] Next, modifications of the machining state predicting device and machining prediction operation according to the first embodiment will be described with reference to FIGS.

[0039] FIG. 8 is a block diagram showing the configuration of a machining state prediction device according to a first modified example of the first embodiment.

[0040] In the machining state prediction device 100 according to the first modification of the first embodiment, the correction value determination unit 136 determines the condition correction value for the machining conditions in the condition change section based on the transmitted machining conditions and information on the condition change section by reading correction value data stored in an external storage device or recording medium such as a database (not shown). At this time, the stored correction value data includes past performance values ​​from actual cutting processes using a thermal cutting machine, machining conditions corresponding to the materials or shapes of various workpieces, etc., and the correction value determination unit 136 has a function of selecting appropriate machining conditions for the condition change section CS to be determined this time from this correction value data.

[0041] This eliminates the need for the correction value determination unit 136 to calculate the correction value in the condition change section CS, thereby improving the prediction speed and reducing the calculation load. Furthermore, by using correction value data based on past machining results, it is possible to change machining conditions in accordance with actual machining, and as a result, the prediction accuracy can be improved.

[0042] Fig. 9 is a top view showing the arrangement of a workpiece and a machining path simulated by a machining prediction device according to a second modified example of the first embodiment. Fig. 10 is a graph showing an example of information on changed machining conditions in the second modified example. Fig. 11 is an example of a two-dimensional image showing a machining state when machining is performed based on the changed machining conditions shown in Fig. 10. Fig. 12 is a two-dimensional image showing an example of a prediction result of a kerf groove after cutting according to the second modified example.

[0043] Fig. 13 is a graph showing another example of information on changed machining conditions in the second modified example of the first embodiment. Fig. 14 is an example of a two-dimensional image showing a machining state when machining is performed based on the changed machining conditions shown in Fig. 13. Fig. 15 is a two-dimensional image showing an example of a predicted result of a kerf groove after cutting based on the changed machining conditions shown in Fig. 13.

[0044] In the second modification of the first embodiment, for example, as shown in Fig. 9, a case is assumed in which machining is performed along the inside of a machining path R2 that starts from a machining start point P1, bends at a midpoint P2, and reaches a machining end point P3. In such a case, there is a section in which the machining speed momentarily becomes zero near the midpoint P2 where the path bends, and therefore it is necessary to change the machining conditions in the section including the midpoint P2.

[0045] More specifically, the condition change section determination unit 134 of the machining state prediction device 100 specifies a change start point P4 of the condition change section CS, where deceleration starts in the section from the machining start point P1 to the midpoint P2 on the machining path R2, based on the information on the machining path and machining conditions determined by the machining path determination unit 130 and the machining condition determination unit 132. Specifically, when the distance from the change start point P4 to the midpoint P2 is L, the machining speed up to the change start point P4 is V, and the acceleration / deceleration time constant of the laser machining machine performing the machining is t, the relationship of the following equation (1) holds.

[0046]

[0047] If the workpiece W is placed on the XY plane, and the coordinates of the machining start point P1 are (X1, Y1), the coordinates of the intermediate point P2 are (X2, Y2), and the coordinates of the change start point P4 are (X4, Y4), then the relationship in equation (2) below holds between the distance L over which deceleration is performed.

[0048]

[0049] Similarly, the condition change section determination unit 134 specifies a change end point P5 of the condition change section CS, where re-acceleration ends, in the section from the midpoint P2 to the machining end point P3, based on the information on the machining path and machining conditions. As in the case of determining the change start point P4, assuming the relationship in equation (1), when the coordinates of the midpoint P2 are (X2, Y2), the coordinates of the machining end point P3 are (X3, Y3), and the coordinates of the change end point P5 are (X5, Y5), the relationship in equation (3) below holds with the distance L for re-acceleration.

[0050]

[0051] The condition change section determination unit 134 calculates the coordinates of the change start point P4 and the change end point P5 from the above relational expressions, determines the condition change section CS based on these, and sends this information to the correction value determination unit 136. Next, the correction value determination unit 136 determines the machining condition items to be changed in the condition change section CS and their correction values ​​(for example, correction values ​​for the machining speed and laser output).

[0052] Next, as shown in Fig. 10, for example, the condition correction processing unit 138 of the machining state prediction device 100 determines changed machining conditions for the entire machining path R2 in association with the machining positions, taking into account the correction values ​​of the machining conditions in the condition change section CS, and sends information on the changed machining conditions to the machining state output unit 140. Next, based on the received information on the changed machining conditions, the machining state output unit 140 creates output data predicting the machining state when cutting is actually performed, as shown in Fig. 11, for example.

[0053] That is, with the predicted output data, cutting starts at the cutting start point P1 under the cutting conditions of a cutting speed V1, a laser beam spot BS1, and a molten pool PD1. Then, at the change start point P4 of the condition change section CS, the cutting conditions are changed to a cutting speed V2 and a beam spot BS2, and this cutting is continued until the midpoint P2 is reached.

[0054] Next, after the machining path R2 is bent once at the midpoint P2, cutting continues in the condition change section CS up to the change end point P5 under machining conditions of machining speed V2, laser beam spot BS2, and molten pool PD1. Then, at the change end point P5 of the condition change section CS, the machining conditions are returned to machining speed V1 and beam spot BS1, and cutting continues up to the machining end point P3.

[0055] Then, the machining state output unit 140 creates a two-dimensional image of the shape prediction result of the kerf groove CG on the workpiece W after cutting, as shown in Fig. 12, for example, in addition to the two-dimensional image shown in Fig. 11. In the example shown in Fig. 12, even if the machining path R2 includes a bending machining point, the width H of the kerf groove CG becomes uniform over the entire machining path R2 by adjusting both the machining speed and the laser output in the condition change section CS.

[0056] As another specific example of the second modified example of the first embodiment, the correction value determination unit 136 may adjust the machining conditions to be changed in the condition change section CS so as to change continuously. Subsequently, the condition correction processing unit 138 of the machining state prediction device 100 determines changed machining conditions for the entire machining path R2 in association with the machining positions, taking into account the correction values ​​of the machining conditions in the condition change section CS, and sends information on the changed machining conditions to the machining state output unit 140.

[0057] That is, the modified processing conditions are, for example, as shown in FIG. 13, modified so that the laser output is continuously decelerated and reduced in the section from the change start point P4 to the midpoint P2 of the condition change section CS, and the laser output is continuously accelerated and increased in the section from the midpoint P2 to the change end point P5.

[0058] Next, the machining state output unit 140 creates output data, such as that shown in FIG. 14, which predicts the machining state when cutting is actually performed, based on the received information on the changed machining conditions.

[0059] That is, with the predicted output data, cutting is started at the cutting start point P1 under the cutting conditions of a cutting speed V1, a laser beam spot BS1, and a molten pool PD1. Then, in the condition change section CS from the change start point P4 to the midpoint P2, cutting is performed in which the cutting speed becomes zero and the cutting conditions are continuously changed to form a beam spot BS2.

[0060] Next, after the machining path R2 bends once at midpoint P2, in the condition change section CS up to the change end point P5, cutting processing continues with the machining conditions changing continuously so that the machining speed changes from zero to V1, the beam spot changes from BS2 to BS1, and the molten pool changes from PD2 to PD1. Next, at the change end point P5 of the condition change section CS, the machining conditions are returned to V1, and the beam spot is BS1, and cutting processing continues up to the machining end point P3.

[0061] At this time, as shown in Figure 14, since the diameter of the molten pool changes continuously from PD1 to PD2 in the condition change section CS, it is preferable to perform conventional position control of the laser beam irradiation point so that the outer periphery of the molten pool PD1 or PD2 is moved so as to be in contact with the processing path R2.

[0062] The machining state output unit 140 then creates a two-dimensional image of the shape prediction result of the kerf groove CG on the workpiece W after cutting, as shown in Fig. 15, for example, in addition to the two-dimensional image shown in Fig. 14. In the example shown in Fig. 15, even if the machining path R2 includes a bending machining point, it is possible to machine the kerf groove CG to a position closer to the midpoint P2 by continuously changing the machining speed and laser output in the condition change section CS and controlling the position of the irradiation point so that the outer periphery of the molten pool formed by the laser beam in the condition change section CS follows the machining path R2.

[0063] Fig. 16 is a top view showing the arrangement of the workpiece and machining path simulated by the machining prediction device according to the third modified example of the first embodiment. Fig. 17 is a graph showing an example of information on changed machining conditions in the third modified example. Fig. 18 is an example of a two-dimensional image showing the machining state when machining is performed based on the changed machining conditions shown in Fig. 17. Fig. 19 is a two-dimensional image showing an example of a prediction result of the kerf groove after cutting according to the third modified example.

[0064] In the third modified example of the first embodiment, as shown in Fig. 16, machining is performed along the inside of a machining path R2 that starts at a machining start point P1, bends at a midpoint P2, and reaches a machining end point P3, and the condition change section CS in the first modified example is further divided into a plurality of sections to change the machining conditions in a plurality of stages. In the specific example of Fig. 16, the section of the condition change section CS where the speed is decelerated toward the midpoint P2 is divided into two sections, a first change section CS1 and a second change section CS2, and the section of the condition change section CS where the speed is accelerated from the midpoint P2 is divided into two sections, a third change section CS3 and a fourth change section CS4.

[0065] More specifically, the condition change section determination unit 134 of the machining state prediction device 100 specifies a change start point P4 at which the first deceleration starts and a first additional change point P6 at which the second acceleration / deceleration starts in the section from the machining start point P1 to the midpoint P2 on the machining path R2, based on the information on the machining path and machining conditions determined by the machining path determination unit 130 and the machining condition determination unit 132. At this time, the coordinate value of the first additional change point P6 can be obtained using, for example, the above-mentioned equation (2).

[0066] Similarly, the condition change section determination unit 134 identifies a second additional change point P7 at which the first re-acceleration ends and a change end point P5 at which the machining speed returns to the machining speed specified in the machining program in the section from the midpoint P2 to the machining end point P3, based on the information on the machining path and machining conditions. At this time, the coordinate value of the second additional change point P7 can be obtained using, for example, the above-mentioned equation (3).

[0067] The condition-change section determination unit 134 calculates the coordinate values ​​of the change start point P4 and the first added change point P6 from the above relational expressions, and determines the first change section CS1 and the second change section CS2. Similarly, the condition-change section determination unit 134 calculates the coordinate values ​​of the second added change point P7 and the change end point P5 from the above relational expressions, and determines the third change section CS3 and the fourth change section CS4. The condition-change section determination unit 134 then sends information about the first change section CS1 to the fourth change section CS4 determined as described above to the correction value determination unit 136.

[0068] Next, the correction value determination unit 136 determines the items of the machining conditions to be set in the first change section CS1 to the fourth change section CS4 of the condition change section CS and their correction values ​​(for example, correction values ​​for the machining speed and laser output).The correction value determination unit 136 then sends information on the machining conditions to be changed in the first change section CS1 to the fourth change section CS4 determined as described above and their correction values ​​to the condition correction processing unit 138.

[0069] Next, as shown in Fig. 17, for example, the condition correction processing unit 138 of the machining state prediction device 100 determines changed machining conditions for the entire machining path R2 in association with the machining positions, taking into account the correction values ​​of the machining conditions in the condition change section CS, and sends information on the changed machining conditions to the machining state output unit 140. Next, based on the received information on the changed machining conditions, the machining state output unit 140 creates output data predicting the machining state when cutting is actually performed, as shown in Fig. 16, for example.

[0070] That is, with the predicted output data, cutting begins at the cutting start point P1 under the cutting conditions of cutting speed V1, laser beam spot BS1, and molten pool PD1. Next, at the change start point P4 of the condition change section CS, the cutting speed is changed to V2 and the beam spot BS3, and cutting continues to the first change point P6. Next, at the first change point P6, the cutting speed is changed to V3 and the beam spot BS2, and cutting continues to the midpoint P2.

[0071] Then, after the machining path R2 is bent once at the midpoint P2, cutting continues under machining conditions of machining speed V3 and beam spot BS2. Next, at the second change point P7, the machining speed is changed to V2 and the beam spot is BS3, and cutting continues up to the first change point P6. Next, at the change end point P5, the machining conditions are returned to machining speed V1 and beam spot BS1, and cutting continues up to the machining end point P3.

[0072] Then, the machining state output unit 140 creates a two-dimensional image of the shape prediction result of the kerf groove CG on the workpiece W after cutting, in addition to the two-dimensional image shown in Fig. 18, as shown in Fig. 19. In the example shown in Fig. 19, even in the machining path R2 that includes a bending machining point, the condition change section CS is further divided into a plurality of sections and machining conditions are changed in a plurality of stages, thereby making it possible to adjust the width H of the kerf groove CG more precisely.

[0073] With the above-described configuration, the machining prediction device according to the first embodiment analyzes the machining program that controls the operation of the thermal cutting machine, identifies the condition change section from the machining path and machining condition information obtained from the command block, and determines the changed machining conditions taking into account the correction value for the condition change section, thereby predicting the machining state of the thermal cutting machine without the control delay caused by the operation of measuring and correcting the actual speed during machining. Furthermore, by using the prediction results, it is possible to control the machining of the thermal cutting machine without the above-described control delay.

[0074] Second Embodiment Fig. 20 is a schematic diagram showing the overall configuration of a thermal cutting machine including a processing control device according to a second embodiment of the present disclosure. Fig. 21 is a block diagram showing the configuration of the processing control device according to the second embodiment. In the second embodiment, in the schematic diagrams shown in Figs. 1 to 19, components that can adopt the same or common components as those in the first embodiment are assigned the same reference numerals, and repeated description of these components will be omitted.

[0075] The thermal cutting machine 1 to which the processing control device 200 according to the second embodiment of the present disclosure is applied is, for example, a laser processing device, and as an example thereof, as shown in FIG. 20, includes a laser oscillator 10 that oscillates processing laser light LB, a processing table 20 that holds the workpiece W, a processing head 30 that irradiates the processing laser light LB onto the workpiece W, a conveying mechanism 40 that moves the processing head 30 relative to the processing table 20, and a processing control device 200 that controls a predetermined laser processing operation on the workpiece W.

[0076] The laser oscillator 10 is a laser source with a wavelength that has high absorption efficiency depending on the material of the workpiece W to be processed. Examples of such a laser oscillator 10 include a YAG laser, a YVO ４ Examples include lasers that can be transmitted through fiber, such as lasers, fiber lasers, and disk lasers. The processing laser light LB output from the laser oscillator 10 is transmitted to the processing head 30 via a transmission path 12, such as an optical fiber.

[0077] The processing table 20 includes, for example, a chuck mechanism (not shown) for mounting the workpiece W, and is configured to grip and fix the workpiece W. The processing table 20 may also include, for example, a rotation mechanism in addition to a mechanism for moving the workpiece W in three axial directions of X, Y, and Z.

[0078] As an example, the processing head 30 introduces a processing laser beam LB from one end (upper end) side and emits it from a nozzle 32 on the other end (lower end) side toward the workpiece W. At this time, a focusing lens (not shown) arranged inside the processing head 30 focuses the processing laser beam LB to a predetermined beam diameter at a focusing point FP on the workpiece W.

[0079] High-pressure oxygen gas, compressed air, or the like is introduced into the processing head 30 and sprayed as an assist gas for the laser cutting process coaxially with the processing laser beam LB from the nozzle 32. Furthermore, the processing head 30 may have a built-in output sensor (not shown) that measures the laser output value P of the processing laser beam LB and transmits the detection signal to the processing control device 200.

[0080] As an example, the transport mechanism 40 is configured as a linear drive body that moves relatively in three mutually orthogonal axis directions, X, Y and Z, and has the processing head 30 attached to one end of the linear drive body. Note that the transport mechanism 40 may also be configured as a six-axis or seven-axis industrial robot equipped with a robot arm having the processing head 30 attached to one end.

[0081] As an example, as shown in FIG. 21 , the machining control device 200 according to the second embodiment includes a main control unit 210, a program analysis unit 220, a machining path determination unit 230, a machining condition determination unit 232, a condition change section determination unit 234, a correction value determination unit 236, a condition correction processing unit 238, a display device 250, and an input unit 260.

[0082] The main control unit 210 of the second embodiment controls the overall operation of the machining state prediction device 200 and has the function of transmitting and receiving various signals by connecting to peripheral devices. As an example, as shown in Figures 20 and 21 , the main control unit 210 reads a machining program that controls the operation of the thermal cutting machine from an external storage device or recording medium such as a database (not shown) and sends it to the program analysis unit 220, and also outputs various operation command signals to each component of the thermal cutting machine 1 based on the changed machining conditions received from the condition correction processing unit 238.

[0083] As in the first embodiment, the program analysis unit 220 receives and analyzes the machining program from the main control unit 210 and determines what command blocks are included in the machining program. The program analysis unit 220 then sends information about the determined command blocks of the machining program to the machining path determination unit 230 and the machining condition determination unit 232.

[0084] As in the first embodiment, the machining path determination unit 230 determines the machining path along which the thermal cutting machine operates, based on the information of the command block analyzed by the program analysis unit 220. Information on the determined machining path is sent to the condition change section determination unit 234.

[0085] As in the first embodiment, the machining condition determination unit 232 determines the machining conditions for the machining that the thermal cutting machine will actually perform, based on the information in the command block analyzed by the program analysis unit 220. Information on the determined machining conditions is sent to the condition change section determination unit 234.

[0086] As in the first embodiment, the condition change section determination unit 234 associates the received machining path information with the machining condition information, determines which section of the machining path needs to have the machining conditions changed, and determines the condition change section on the machining path where the machining conditions will be changed.The condition change section determination unit 234 then sends the determined condition change section information to the correction value determination unit 236 together with the above-mentioned machining path and machining condition information.

[0087] The correction value determination unit 236 determines the condition correction value for the machining conditions in the condition change section based on the information on the machining conditions and the condition change section, as in the first embodiment. Then, the correction value determination unit 236 sends the information on the determined condition correction value to the condition correction processing unit 238 together with the information on the machining path, the machining conditions, and the condition change section.

[0088] The condition correction processing unit 238 determines the changed machining conditions in the condition change section based on the condition correction value sent, as in the first embodiment. Then, the condition correction processing unit 238 sends information on the machining conditions obtained by changing the changed machining conditions in the condition change section in the machining path determined by the machining path determination unit 230, together with information on the associated machining path, to the main control unit 210.

[0089] The display device 250 displays various parameter command values ​​for cutting processing executed by the thermal cutting machine 1 sent from the main control unit 210, detection information obtained from various sensors, etc. The display device 250 can also display the above-mentioned changed processing conditions as a predicted diagram of the entire processing path.

[0090] The input unit 260 is configured as a data input means that allows an operator using the machining control device 200 to directly input various machining conditions and parts of the machining program to correct or update them. Although Figures 20 and 21 show an example in which the display device 250 and the input unit 260 are configured as separate entities, they may also be configured to be integrated using, for example, a touch panel type display device.

[0091] By having the above-mentioned configuration, the processing control device according to the second embodiment can analyze the processing program and identify the condition change section and its correction value for changing the processing conditions without actually performing test cutting processing, so that it is possible to control the processing of the thermal cutting machine without the control delay caused by the operation of measuring and correcting the actual speed during processing.

[0092] Although the present disclosure has been described in detail above, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments.

[0093] For example, in the description of the above embodiment, the processing conditions that are changed in laser cutting processing are exemplified as changing the processing speed and the laser output of the laser beam, but the processing conditions may also be changed as the spot diameter of the laser beam, the pulse frequency or duty ratio when the laser beam is pulsed, etc.

[0094] The following additional notes are further disclosed regarding the above-described embodiment and modifications.

[0095] (Supplementary Note 1) A machining state prediction device including: a program analysis unit that reads a machining program that controls the operation of a thermal cutting machine and analyzes a command block; a machining path determination unit that determines a machining path of the thermal cutting machine based on the analyzed command block; a machining condition determination unit that determines machining conditions for the thermal cutting machine based on the analyzed command block; a condition change section determination unit that determines a condition change section on the machining path where the machining conditions are changed based on the machining path and the machining conditions; a correction value determination unit that determines a condition correction value in the condition change section; a condition correction processing unit that determines changed machining conditions in the condition change section based on the condition correction value; and a machining state output unit that outputs a prediction result of the machining state for the entire machining path reflecting the changed machining conditions. (Supplementary Note 2) The machining state prediction device according to Supplementary Note 1, wherein the correction value determination unit determines the condition correction value by performing arithmetic processing based on a predetermined arithmetic expression. (Supplementary Note 3) The machining state prediction device according to Supplementary Note 1, wherein the correction value determination unit determines the condition correction value by reading out the condition correction value stored in a predetermined storage device. (Supplementary Note 4) The machining state prediction device according to any one of Supplementary Notes 1 to 3, wherein the condition change section determination unit defines the condition change section by a plurality of divided sections, and the correction value determination unit determines the condition correction value for each of the plurality of divided sections. (Supplementary Note 5) The machining state prediction device according to any one of Supplementary Notes 1 to 4, wherein the condition correction value is an output condition of the thermal cutting machine.(Supplementary Note 6) A machining control device including: a program analysis unit that reads a machining program that controls the operation of a thermal cutting machine and analyzes a command block; a machining path determination unit that determines a machining path of the thermal cutting machine based on the analyzed command block; a machining condition determination unit that determines machining conditions of the thermal cutting machine based on the analyzed command block; a condition change section determination unit that determines a condition change section on the machining path where the machining conditions are changed based on the machining path and the machining conditions; a correction value determination unit that determines a condition correction value in the condition change section; a condition correction processing unit that determines changed machining conditions in the condition change section based on the condition correction value; and a main control unit that outputs a machining control command for the entire machining path based on the machining conditions reflecting the changed machining conditions. (Supplementary Note 7) The machining control device according to Supplementary Note 6, wherein the correction value determination unit determines the condition correction value by performing arithmetic processing based on a predetermined arithmetic expression. (Supplementary Note 8) The machining control device according to Supplementary Note 6, wherein the correction value determination unit determines the condition correction value by reading out the condition correction value stored in a predetermined storage device. (Supplementary Note 9) The processing control device according to any one of Supplementary Notes 6 to 8, wherein the condition change section determination unit defines the condition change section by a plurality of divided sections, and the correction value determination unit determines the condition correction value for each of the plurality of divided sections. (Supplementary Note 10) The processing control device according to any one of Supplementary Notes 6 to 9, wherein the condition correction value is an output condition of the thermal processing cut-off machine.

[0096] REFERENCE SIGNS LIST 1 Thermal cutting machine 10 Laser oscillator 12 Transmission path 20 Machining table 30 Machining head 32 Nozzle 40 Conveying mechanism 100 Machining state prediction device 110 Main control unit 120 Program analysis unit 130 Machining path determination unit 132 Machining condition determination unit 134 Condition change section determination unit 136 Correction value determination unit 138 Condition correction processing unit 140 Machining state output unit 200 Machining control device 210 Main control unit 220 Program analysis unit 230 Machining path determination unit 232 Machining condition determination unit 234 Condition change section determination unit 236 Correction value determination unit 238 Condition correction processing unit 250 Display device 260 Input unit

Claims

1. A program analysis unit that reads a processing program for controlling the operation of a thermal cutting machine and analyzes command blocks, A machining path determination unit that determines a machining path of the thermal cutting machine based on the analyzed command blocks, A machining condition determination unit that determines machining conditions of the thermal cutting machine based on the analyzed command blocks, A condition change section determination unit that determines a condition change section on the machining path where the machining conditions are changed based on the machining path and the machining conditions, A correction value determination unit that determines a condition correction value in the condition change section, A condition correction processing unit that determines changed machining conditions in the condition change section based on the condition correction value, A machining state output unit that outputs a prediction result of the machining state for the entire machining path reflecting the changed machining conditions, A machining state prediction device including the above.

2. The correction value determination unit determines the condition correction value by performing arithmetic processing based on a predetermined arithmetic expression. The machining state prediction device according to claim 1.

3. The correction value determination unit determines the condition correction value by reading the condition correction value stored in a predetermined storage device. The machining state prediction device according to claim 1.

4. The condition change section determination unit defines the condition change section by a plurality of divided sections, The correction value determination unit determines the condition correction value for each of the plurality of divided sections. The machining state prediction device according to any one of claims 1 to 3.

5. The condition correction value is an output condition of the thermal cutting machine. The machining state prediction device according to any one of claims 1 to 3.

6. A program analysis unit that reads a processing program for controlling the operation of a thermal cutting machine and analyzes command blocks, A machining path determination unit that determines a machining path of the thermal cutting machine based on the analyzed command blocks, A machining condition determination unit that determines machining conditions of the thermal cutting machine based on the analyzed command blocks, A condition change section determination unit that determines a condition change section on the machining path where the machining conditions are changed based on the machining path and the machining conditions, A correction value determination unit that determines a condition correction value in the condition change section, A condition correction processing unit that determines changed machining conditions in the condition change section based on the condition correction value, A main control unit that outputs a machining control command for the entire machining path based on the machining conditions reflecting the changed machining conditions, A machining control device including the above.

7. The correction value determination unit determines the conditional correction value by performing arithmetic processing based on a predetermined arithmetic expression. The machining control device according to claim 6. **Claim 8** The correction value determination unit determines the conditional correction value by reading the conditional correction value stored in a predetermined storage device. The machining control device according to claim 6. **Claim 9** The condition change interval determination unit defines the condition change interval by a plurality of divided intervals. The correction value determination unit determines the conditional correction value for each of the plurality of divided intervals. The machining control device according to any one of claims 6 to 8. **Claim 10** The conditional correction value is an output condition of the thermal cutting machine. The machining control device according to any one of claims 6 to 8.