Apparatus for estimating processing state and method for estimating processing state

Abstract

This machining state estimation device comprises a storage device and a processor. The storage device stores a parameter defining the machining state of a press machine, standard reference data corresponding to the parameter, and region shape information defining the length of a plurality of regions obtained by dividing a punching outline from the press machine. The processor acquires measurement data indicating a measurement result regarding the machining load of the press machine. The processor generates total reference data pertaining to the machining load on the basis of at least one of a plurality of the standard reference data and the region shape information. The processor determines a degree of similarity, which is an indicator of the degree of similarity between the total reference data and the measurement data. The processor estimates the machining state in each of the plurality of regions on the basis of the determined degree of similarity.

Description

Technical Field

[0001] The present disclosure relates to a processing state estimation device and a processing state estimation method.

Background Art

[0002] Patent Document 1 discloses a technique for obtaining a determination value by synthesizing state quantities in a normal facility and state quantities in an abnormal facility in a device that repeats the same operation, such as a press machine, in a relatively short cycle. The determination device of Patent Document 1 generates an alarm when the state quantity of the target device exceeds the determination value or falls below the determination value.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] However, the conventional technology only detects whether the state quantity exceeds the determination value and cannot detect partial abnormalities such as partial wear of the tool.

[0005] An object of the present disclosure is to provide a processing state estimation device and a processing state estimation method that can estimate the processing state by a press machine with higher accuracy than the conventional technology.

[0006] A processing state estimation device according to one aspect of the present disclosure includes a storage device and a processor, wherein the storage device stores parameters defining the processing state of a press machine, reference reference data corresponding to the parameters, and region shape information defining the lengths of a plurality of regions obtained by dividing the punching contour by the press machine, and the processor obtains measurement data indicating the measurement result of the processing load by the press machine, Based on at least one of the plurality of reference data and the area shape information, a comprehensive reference data relating to the processing load is generated. The similarity index, which is an indicator of the degree of similarity between the aforementioned comprehensive reference data and the aforementioned measurement data, is determined. Based on the determined similarity, the processing state in each of the multiple areas is estimated.

[0007] A method for estimating the processing state according to one aspect of this disclosure is: The processor acquires measurement data showing the measurement results of the processing load by the press machine, The processor generates comprehensive reference data relating to the processing load based on reference reference data corresponding to parameters defining the processing state of the press machine and area shape information defining the lengths of multiple areas obtained by dividing the punched contour by the press machine. The processor performs the steps of determining a similarity score, which is an indicator of the degree of similarity between the aggregated reference data and the measurement data, The processor estimates the processing state in each of the plurality of regions based on the determined similarity, Includes.

[0008] According to the processing state estimation device and processing state estimation method described herein, the processing state by a press machine can be estimated with greater accuracy than in the prior art. [Brief explanation of the drawing]

[0009] [Figure 1] This is a block diagram showing an example configuration of a processing state estimation device according to the first embodiment. [Figure 2] Figure 1 is a schematic cross-sectional view showing a press machine to which the load sensor is attached. [Figure 3] Figure 1 is a schematic graph showing an example of a measurement waveform from the load sensor. [Figure 4] This is a schematic diagram illustrating the overview of the machining state estimation process performed by the machining state estimation device shown in Figure 1. [Figure 5] It is a schematic cross-sectional view for explaining the punching outline area of the press machine in FIG. 2. [Figure 6] It is a schematic diagram exemplifying parameters in each area of the punching outline. [Figure 7] It is a table showing an example of the state data shown in FIG. 1. [Figure 8] It is a flowchart exemplifying the procedure of the machining state estimation process executed by the CPU of the machining state estimation device in FIG. 1. [Figure 9] It is a flowchart exemplifying the normal state estimation process S5 shown in FIG. 8. [Figure 10] It is a flowchart exemplifying the workpiece thickness estimation process S50 shown in FIG. 9. [Figure 11] It is a flowchart exemplifying the reference waveform generation process S501 corresponding to the state data in FIG. 10. [Figure 12] It is a flowchart exemplifying the reference waveform generation process S505 corresponding to the provisional state data in FIG. 10. [Figure 13] It is a flowchart exemplifying the punch wear amount estimation process S51 in FIG. 9. [Figure 14] It is a flowchart exemplifying the die wear amount estimation process S52 in FIG. 9. [Figure 15] It is a flowchart exemplifying the processing flow of the post-polishing state estimation process S6 shown in FIG. 8. [Figure 16] It is a flowchart exemplifying the clearance estimation process S63 after polishing shown in FIG. 15. [Figure 17] It is a flowchart exemplifying the post-replacement state estimation process S7 shown in FIG. 8. [Figure 18] It is a table showing an example of state data in the machining state estimation device according to the second embodiment of the present disclosure.

Embodiments for Carrying Out the Invention

[0010] (Knowledge on which the present disclosure is based) The inventors of this invention have conducted extensive research to accurately estimate the processing state of a press machine in press working, particularly in punching, and have obtained the following findings. Here, "processing state" refers to at least one of the following: tool wear, clearance, or workpiece thickness.

[0011] The load applied to the punch or workpiece during punching depends on values ​​such as punch wear, die wear, clearance, and workpiece thickness.

[0012] Punch wear and die wear are examples of punch wear parameters, which are indicators of the degree of punch wear, and die wear parameters, which are indicators of the degree of die wear, respectively. Tool wear, such as punch wear and die wear, can be expressed, for example, as a change in dimensions from the design value of the tool. Tool wear may also be expressed as a change in shape, volume, mass, etc. Alternatively, tool wear may be expressed as the radius of an arc when the wear is approximated as a circular arc.

[0013] Clearance is the gap between the die and the punch. For example, clearance is the gap between the die and the punch when a punched hole is made in a workpiece. Clearance may also be expressed as the ratio of the gap between the die and the punch to the thickness of the workpiece.

[0014] Since the load depends on these parameters, it is conceivable to estimate these parameters from the load waveform obtained during processing. For example, if tool wear such as punch wear and die wear can be estimated, the optimal timing for tool sharpening or regrinding (hereinafter simply referred to as "sharpening") can be determined in a press machine performing cycle processing. By sharpening the tool at the optimal timing, it is possible to prevent situations such as processing workpieces with worn tools and producing a large number of defective products, thereby increasing productivity.

[0015] In presses that perform cyclic processing, there is an advantage to using the estimated processing state from the previous punching operation to estimate the processing state. One reason for this is that values ​​such as clearance, punch wear, and die wear usually do not change significantly from the values ​​in the previous punching operation. By performing estimations under the condition that the results do not change significantly from the previous estimation, the accuracy of the estimation can be improved.

[0016] In addition to the above findings, the inventors have further discovered that wear on tools such as punches and dies in press machines does not necessarily progress uniformly along the entire length of the tool's contour, but can progress only in a portion of the contour. Furthermore, the inventors have found that when partial wear occurs on a portion of the tool's contour, the progression of this partial wear tends to be faster than that of other parts. When rapid partial wear occurs, the sides of the tool, such as the punch, can be worn down, leading to an increase in clearance.

[0017] Based on these findings, the inventors discovered that the accuracy of estimation can be improved by estimating the processing state in multiple parts of the punched contour defined by, for example, the shape of the punch and die of a press machine, and thus arrived at the present invention.

[0018] According to a first aspect of this disclosure, a device comprising a storage device and a processor, The aforementioned storage device is Parameters that define the processing state of the press machine, Each of these corresponds to a reference data set for the aforementioned parameter, The system stores area shape information that defines the lengths of multiple areas obtained by dividing the punched-out contour by the press machine, The aforementioned processor, Measurement data showing the measurement results of the processing load by the aforementioned press machine is obtained. Based on the aforementioned reference data and the area shape information, comprehensive reference data relating to the processing load is generated. The similarity index, which is an indicator of the degree of similarity between the aforementioned comprehensive reference data and the aforementioned measurement data, is determined. Based on the determined similarity, the processing state in each of the plurality of areas is estimated. The present invention provides a device for estimating the processing state.

[0019] According to a second aspect of this disclosure, the parameter defines the processing state per predetermined unit length of the punched contour, The aforementioned reference data corresponds to the parameter per predetermined unit length of the punched contour, In the process of generating the integrated reference data, the processor, For each area, area data relating to the processing load is generated for each area by multiplying the reference data by the ratio of the length of the area to the unit length as defined in the area shape information. By combining the area data for each of the aforementioned areas, a comprehensive reference data relating to the processing load over the entire length of the punched-out contour is generated. The present invention provides a processing state estimation device according to the first embodiment.

[0020] According to a third aspect of the present disclosure, the processor provides a processing state estimation device according to the second aspect, which generates comprehensive reference data relating to the processing load over the entire length of the punched contour by calculating the sum of the area data for each of the areas.

[0021] According to a fourth aspect of the present disclosure, the processor subdivides the specified area into a plurality of sub-areas based on a subdivision instruction signal which includes information for specifying at least one of the plurality of areas and further subdividing the specified area into a plurality of sub-areas, The processor, in the process of estimating the processing state, estimates the processing state in each of the regions other than the designated region among the plurality of regions, and estimates the processing state in each of the plurality of sub-regions. The present invention provides a processing state estimation device according to any of the first to third embodiments.

[0022] According to a fifth aspect of this disclosure, the processor is Search for the comprehensive reference data that has the greatest similarity to the aforementioned measurement data. The parameters corresponding to the reference reference data, which is the basis of the searched comprehensive reference data, are determined as estimated parameters representing the processing state of the measurement data at the time of measurement. The present invention provides a processing state estimation device according to any of the first to fourth embodiments.

[0023] According to a sixth aspect of this disclosure, the processor provides a processing state estimation device according to the fifth aspect, wherein in the process of searching for the comprehensive reference data, the processor sequentially changes the parameters within a predetermined range based on the estimation parameters already determined by the processor, and searches for comprehensive reference data that has the greatest similarity to the measurement data.

[0024] According to a seventh aspect of this disclosure, the parameter includes a clearance parameter that defines the clearance of the press machine, The estimated parameters include the estimated clearance parameters estimated as the clearance parameters at the time of measurement of the measurement data. The present invention provides a processing state estimation device according to the fifth or sixth embodiment.

[0025] According to an eighth aspect of this disclosure, the area shape information includes clearance correlation information indicating whether the clearance parameter of one area correlates with the clearance parameter of another area. If the clearance correlation information, which indicates that the clearance parameter of one area correlates with the clearance parameter of the other area, is included in the area shape information, the processor, when sequentially changing the clearance parameter in the process of searching the integrated reference data, changes the clearance parameter of the other area in accordance with the amount of change applied to the clearance parameter of the one area. The present invention provides a processing state estimation device according to the seventh aspect.

[0026] According to a ninth aspect of the present disclosure, the parameter includes a punch wear parameter that defines the degree of wear of the punch of the press machine, The estimated parameters include estimated punch wear parameters estimated as the punch wear parameters at the time of measurement of the measurement data, The present invention provides a processing state estimation device according to any of the fifth to eighth embodiments.

[0027] According to a tenth aspect of the present disclosure, the processor provides a machining state estimation device according to the ninth aspect, wherein in the process of searching for the overall reference data, the processor sequentially changes the punch wear parameter within a value greater than or equal to the estimated punch wear parameter to search for the overall reference data that has the greatest similarity to the measurement data.

[0028] According to an eleventh aspect of this disclosure, the area shape information includes information indicating whether the punched-out contour in each of the plurality of areas is straight or curved, The aforementioned processor, The punch wear parameter in the area where the punched-out contour is linear is fixed to the estimated punch wear parameter, and the punch wear parameter in the area where the punched-out contour is curved is sequentially changed within a value greater than or equal to the estimated punch wear parameter to search for a comprehensive reference data that has the maximum first similarity with the measured data. The punch wear parameter for the area where the punched-out contour is curved, corresponding to the aggregate reference data with the highest first similarity, is determined as the estimated punch wear parameter for the area where the punched-out contour is curved. The punch wear parameter in the area where the punched contour is curved is fixed to the estimated punch wear parameter in the area where the punched contour is curved, and the punch wear parameter in the area where the punched contour is straight is sequentially changed within a value greater than or equal to the estimated punch wear parameter to search for a comprehensive reference data that maximizes the second similarity with the measured data. The punch wear parameter for the area where the punched-out contour is linear, corresponding to the overall reference data with the highest second similarity, is determined as the estimated punch wear parameter for the area where the punched-out contour is linear. The present invention provides a processing state estimation device according to the ninth or tenth embodiment.

[0029] According to a twelfth aspect of the present disclosure, the processing state estimation device according to any of the ninth to eleventh aspects is provided, wherein the processor sets the estimated punch wear parameter to an initial value when it receives a signal indicating that the punch has been replaced or polished.

[0030] According to a thirteenth aspect of this disclosure, the parameter includes a die wear parameter that defines the degree of wear of the die of the press machine, The estimated parameters include estimated die wear parameters estimated as the die wear parameters at the time of measurement of the measurement data. The present invention provides a processing state estimation device according to any of the fifth to twelfth embodiments.

[0031] According to a fourteenth aspect of this disclosure, the processor, in the process of searching for the aggregate reference data, sequentially changes the die wear parameter within a value greater than or equal to the estimated die wear parameter to search for the aggregate reference data that has the greatest similarity to the measurement data. The present invention provides a processing state estimation device according to the 13th embodiment.

[0032] According to a 15th aspect of this disclosure, the area shape information includes information indicating whether the punched-out contour in each of the plurality of areas is straight or curved, The aforementioned processor, The die wear parameter in the area where the punched-out contour is linear is fixed to the estimated die wear parameter, and the die wear parameter in the area where the punched-out contour is curved is sequentially changed within a value greater than or equal to the estimated die wear parameter to search for a comprehensive reference data that has the maximum third similarity to the measured data. The die wear parameter for the area where the punched-out contour is curved, corresponding to the comprehensive reference data with the highest third similarity, is determined as the estimated die wear parameter for the area where the punched-out contour is curved. The die wear parameter in the area where the punched-out contour is curved is fixed to the estimated die wear parameter in the area where the punched-out contour is curved, and the die wear parameter in the area where the punched-out contour is straight is sequentially changed within a value greater than or equal to the estimated die wear parameter to search for a comprehensive reference data that maximizes the fourth similarity with the measurement data. The die wear parameter for the area where the punched-out contour is linear, corresponding to the composite reference data with the highest similarity of the fourth, is determined as the estimated die wear parameter for the area where the punched-out contour is linear. The present invention provides a processing state estimation device according to the 13th or 14th embodiment.

[0033] According to a sixteenth aspect of the present disclosure, the processor provides a machining state estimation device according to any of the thirteenth to fifteenth aspects, wherein when it receives a signal indicating that the die has been replaced or polished, it sets the estimated die wear parameter to an initial value.

[0034] According to a 17th aspect of this disclosure, the parameter further includes a workpiece thickness parameter that defines the thickness of the workpiece processed by the press machine, In the process of searching for the aggregate reference data, the processor sequentially changes the workpiece thickness parameter to search for the aggregate reference data that has the greatest similarity to the measurement data. The present invention provides a processing state estimation device according to any of the 5th to 16th embodiments.

[0035] According to one aspect of this disclosure, the processor includes the steps of acquiring measurement data showing the measurement result of the processing load by a press machine, The processor generates comprehensive reference data relating to the processing load based on at least one of a plurality of reference data corresponding to each combination of a plurality of parameters that define the processing state of the press machine, and area shape information that defines the lengths of a plurality of areas obtained by dividing the punching contour defined by the shape of the punch and die of the press machine. The processor performs the steps of determining a similarity score, which is an indicator of the degree of similarity between the aggregated reference data and the measurement data, The processor estimates the processing state in each of the plurality of regions based on the determined similarity, The present invention provides a method for estimating the processing state, including [specific details omitted].

[0036] Embodiments of this disclosure will be described in detail below, with reference to the drawings as appropriate. However, unnecessary details may be omitted. For example, detailed explanations of already well-known matters or redundant explanations of substantially identical configurations may be omitted. This is to avoid the following explanation becoming unnecessarily verbose and to facilitate understanding by those skilled in the art. The inventors provide the accompanying drawings and the following explanation so that those skilled in the art can fully understand this disclosure, and do not intend to limit the subject matter described in the claims by means of these.

[0037] (First Embodiment) [1. Structure] Figure 1 is a block diagram showing an example configuration of a machining state estimation device 100 according to the first embodiment of the present disclosure. The machining state estimation device 100 comprises a CPU 1, a storage device 2, an input interface (I / F) 3, and an output interface (I / F) 4.

[0038] CPU1 performs information processing to realize the functions of the processing state estimation device 100, which will be described later. Such information processing is realized, for example, by CPU1 operating according to the instructions of program 21 stored in memory device 2. CPU1 is an example of a processor of this disclosure. The processor does not need to include an arithmetic circuit that performs calculations for information processing, and is not limited to a CPU. For example, the processor may be composed of circuits such as an MPU or FPGA.

[0039] The storage device 2 is a recording medium that stores various information, including data such as the waveform library 23 and state data 22 described later, and the program 21 necessary to realize the functions of the processing state estimation device 100. The storage device 2 can be implemented, for example, as a semiconductor storage device such as flash memory or a solid-state drive (SSD), a magnetic storage device such as a hard disk drive (HDD), or other recording media, either alone or in combination thereof. The storage device 2 may also include volatile memory such as SRAM or DRAM.

[0040] The input interface 3 is an interface circuit that connects the machining state estimation device 100 to an external device in order to input information such as the detection results from the load sensor 11 to the machining state estimation device 100. Such an external device may be, for example, the load sensor 11 or other information processing terminals. The input interface 3 may also be a communication circuit that performs data communication according to an existing wired communication standard or wireless communication standard.

[0041] The output interface 4 is an interface circuit that connects the machining state estimation device 100 to an external output device in order to output information from the machining state estimation device 100. Such an output device may be, for example, a display or another information processing terminal. The output interface 4 may also be a communication circuit that performs data communication according to an existing wired communication standard or wireless communication standard. The input interface 3 and the output interface 4 may be implemented by similar hardware.

[0042] Figure 2 is a schematic cross-sectional view showing the press machine 50 to which the load sensor 11 shown in Figure 1 is attached. For ease of explanation, Figure 2 shows the X, Y, and Z axes, which are orthogonal to each other. The Z axis represents the vertical direction.

[0043] The press machine 50 is an example of a processing machine that performs cyclic processing, which involves repeating the same processing. The press machine 50 comprises a bolster 51 and a slide 52 that repeatedly performs an up-and-down cyclic motion from top dead center to bottom dead center relative to the bolster 51. A die backing plate 61 is mounted on top of the bolster 51, and a die plate 62 is mounted on top of the die backing plate 61. The die plate 62 grips the die 63.

[0044] A punch backing plate 71 is attached to the lower part of the slide 52, and a punch plate 72 is attached to the lower part of the punch backing plate 71. The punch plate 72 grips the punch 73. The press machine 50 further includes a stripper plate 74. The stripper plate 74 is attached to the punch plate 72 or punch backing plate 71 and fasteners such as bolts via positioning guides such as posts (not shown). The stripper plate 74 is biased downward, for example by a compression spring, and has the function of guiding the punch 73 to stay in a constant position, as well as the function of removing material adhering to the punch 73 after punching the workpiece 80, and / or the function of fixing the workpiece 80 when punching the workpiece 80.

[0045] The load sensor 11 is installed, for example, between the punch 73 and the punch backing plate 71. The load sensor 11 is an electrical force sensor, such as a piezoelectric force sensor or a strain gauge type, and measures the load applied to the punch 73 when the punch 73 punches out the workpiece 80.

[0046] Figure 3 is a schematic graph showing an example of a measurement waveform from the load sensor 11. In the graph of Figure 3, the horizontal axis represents time, and the vertical axis represents load. The graph of Figure 3 shows a bell-shaped waveform in which, during punching, a load is applied to the workpiece 80, and therefore to the punch 73 and load sensor 11, from the moment the punch 73 moves down and contacts the workpiece 80, and then the load rapidly decreases to almost zero after the workpiece 80 is punched out. The punching period of the punching process can be measured, for example, as the period from the time when the load exceeds the rising threshold to the time when it falls below the falling threshold in the measurement waveform. Such rising and falling thresholds may be defined as absolute values ​​or as a percentage of the peak value of the load.

[0047] [2. Operation] [2-1. Overview of Operation] The overview of the machining state estimation process will be explained with reference to Figures 4-7. Figure 4 is a schematic diagram illustrating the overview of the machining state estimation process performed by the machining state estimation device 100 in Figure 1.

[0048] CPU1 obtains the unit waveform per unit length of the punched contour of the press machine 50 (hereinafter referred to as "first reference data" or "reference reference data") from the waveform library 23 and generates area waveforms (area data) corresponding to each of the eight areas A1 to A8. CPU1 synthesizes all the area waveforms to generate a reference waveform (hereinafter referred to as "second reference data" or "integrated reference data") and compares the measured waveform with the reference waveform. Since the unit waveform is associated with a parameter that indicates at least one of the following: tool wear amount, clearance, or workpiece thickness, the parameters of each area A1 to A8 can be estimated by searching for a reference waveform with a high degree of agreement with the measured waveform.

[0049] Figure 5 is a schematic cross-sectional view illustrating areas A1-A8 of the punched contour of the press machine 50. The cross-sectional view in Figure 5 shows only the punch 73 and die 63 to facilitate understanding of the explanation.

[0050] The punched-out contour is the outline of the portion of the workpiece 80 that is punched out by the punching process using the press machine 50. The shapes of the punch 73 and die 63 are designed to achieve the desired punched-out contour. The punched-out contour may be the design value of the contour of the punch 73 as viewed from the punching direction, or the design value of the contour of the opening of the die 63 as viewed from the punching direction.

[0051] Areas A1 to A8 of the punched-out contour are obtained by dividing the punched-out contour. Where the punched-out contour is divided is predetermined according to the shape of the punched-out contour. In the example in Figure 5, the punched-out contour is a rounded rectangle, and the punched-out contour is divided between each corner of the rounded rectangle and the straight sections. The first area A1 is the area of ​​the corner section, and following the first area A1 are the second to eighth areas A2 to A8, which are arranged counterclockwise in a plan view. The starting point of the first area A1 when the punched-out contour is viewed counterclockwise in a plan view is used as the reference point for the position of the punched-out contour.

[0052] Figure 6 is a schematic diagram illustrating the parameters in each region of the punched-out contour. Figure 6 illustrates the design value of the clearance (design clearance), the measured value of the clearance (measured clearance), and the amount of punch wear corresponding to each region. As shown in Figure 6, the inventors have found that the clearance and the amount of punch wear are not constant along the entire length of the punched-out contour, but can have a distribution along the contour. The same applies to other parameters such as die wear and workpiece thickness.

[0053] Figure 7 is a table showing an example of state data 22. State data 22 includes contour parameters that define information about the punched contour, tool state parameters that define the tool state, and workpiece state parameters that define the workpiece state. In the example in Figure 7, the contour parameters are the shape, direction, design clearance along the contour, and area length of the punched contour. In the example in Figure 7, the tool state parameters are the punch wear amount, die wear amount, and clearance. In the example in Figure 7, the workpiece state parameter is the workpiece thickness.

[0054] The contour parameters shown in Figure 7 are an example of the "area shape information" of this disclosure. The shape of the punched contour in the contour parameters indicates whether the shape of areas A1 to A8 is an arc or curve R, or a straight line S. The direction indicates the angular direction of areas A1 to A8 relative to the center of the punched contour. The design clearance indicates the design value of the clearance corresponding to each area. The area length indicates the length of the punched contour in each area.

[0055] Regarding the tool condition parameters shown in Figure 7, the punch wear amount, die wear amount, and clearance in the first area A1 are denoted as P1, D1, and C1, respectively. The same applies to the second to eighth areas A2 to A8.

[0056] In the example shown in Figure 7, the workpiece thickness T is constant across the entire area. However, this embodiment is not limited to this, and the workpiece thickness may also take different values ​​for each area, similar to the punch wear, die wear, and clearance.

[0057] For example, the punch wear amounts P1 to P8 can be set to any of the following candidate values: 0 μm, 2 μm, 4 μm, 6 μm, 8 μm, 10 μm, and 12 μm, respectively. For example, the die wear amounts D1 to D8 can be set to any of the following candidate values: 0 μm, 2 μm, 4 μm, 6 μm, 8 μm, 10 μm, and 12 μm, respectively. For example, the clearance can be set to any of the following candidate values: 3 μm, 4 μm, 5 μm, 6 μm, and 7 μm. For example, the workpiece thickness can be set to any of the following candidate values: 46 μm, 48 μm, 50 μm, 52 μm, and 54 μm. Note that the candidate values ​​for punch wear amount, die wear amount, clearance, and workpiece thickness are not limited to these, and the number of candidate values ​​is not limited to the above numbers.

[0058] As in the example above, if there are 7 candidate values ​​for punch wear amount, 7 candidate values ​​for die wear amount, 5 candidate values ​​for clearance, and 5 candidate values ​​for workpiece thickness, then 1225 different unit waveforms are pre-registered in the waveform library 23. In this way, the waveform library 23 is a four-dimensional table in which unit waveforms corresponding to the arrangements of punch wear amount, die wear amount, clearance, and workpiece thickness are registered.

[0059] The waveform library 23 has pre-registered unit waveforms per unit length of the punched profile corresponding to all combinations of punch wear amount, die wear amount, clearance, and workpiece thickness. The unit length is a predetermined unit length, for example, 1 mm. In this embodiment, the unit waveform is a waveform that represents the relationship between time and load, similar to the measurement waveform in Figure 3.

[0060] The unit waveform can be obtained, for example, by actually measuring the punching load or by multiplying the waveform obtained by simulation by the ratio of the unit length to the total length of the punched contour. For example, if the unit length is 1 [mm] and the total length of the punched contour is L [mm], the unit waveform can be obtained by actually measuring the punching load or by multiplying the waveform obtained by simulation by 1 / L.

[0061] As shown in Figures 4 and 7, CPU1 obtains unit waveforms from waveform library 23 that correspond to combinations of punch wear amount, die wear amount, clearance, and workpiece thickness for each area. Next, CPU1 generates area waveforms for each area by multiplying each unit waveform by the area length. As shown in Figure 7, CPU1 generates a reference waveform that shows the load over the entire length of the punched contour by synthesizing the eight area waveforms.

[0062] As shown in Figure 7, CPU1 searches for a reference waveform that has the greatest degree of agreement with the measured waveform, and estimates the combination of parameters corresponding to the unit waveform of each region, which is the basis of the searched reference waveform, as an estimated parameter set representing the processing state of that region.

[0063] [2-2. Flowchart] Figure 8 is a flowchart illustrating the procedure for estimating the machining state, which is performed by the CPU 1 of the machining state estimation device 100 shown in Figure 1.

[0064] First, the CPU 1 acquires a measurement waveform from the load sensor 11 that shows the measurement result of the load applied to the load sensor 11 during press processing by the press machine 50 (S1).

[0065] Next, CPU1 acquires state data 22, which represents the estimated parameter set, which is the result of the previous estimation (S2).

[0066] Next, the CPU1 determines whether a predetermined period has elapsed since the tool change was performed (S3). For example, the CPU1 determines whether a predetermined period has elapsed since receiving a tool change signal indicating that a tool change has been performed. The CPU1 may also determine that a predetermined period has elapsed if press work has been performed a predetermined number of times or more since receiving the tool change signal. Such a tool change signal is transmitted to the CPU1, for example, when the user presses a tool change completion button provided on the user interface of the press machine 50, the processing state estimation device 100, etc.

[0067] If it is determined that a predetermined period has elapsed since the tool was replaced (Yes in S3), the CPU1 determines whether a predetermined period has elapsed since the tool was sharpened (S4). For example, the CPU1 determines whether a predetermined period has elapsed since receiving a die sharpening signal indicating that the die has been sharpened and / or a punch sharpening signal indicating that the punch has been sharpened. The CPU1 may also determine that a predetermined period has elapsed if press operations have been performed a predetermined number of times or more since receiving the die sharpening signal and / or punch sharpening signal. Such signals are transmitted to the CPU1, for example, when the user presses a die sharpening completion button and / or punch sharpening completion button provided on the user interface of the press machine 50, the processing state estimation device 100, etc.

[0068] If it is determined that a predetermined period has elapsed since the tool was sharpened (Yes in S4), CPU1 executes the first state estimation process (hereinafter referred to as the "normal state estimation process") S5. Details of the normal state estimation process S5 will be described later.

[0069] In step S4, if it is determined that a predetermined period has not elapsed since the tool was sharpened (No in S4), CPU1 executes the second state estimation process (hereinafter referred to as the "post-sharpening state estimation process") S6. Details of the post-sharpening state estimation process S6 will be described later.

[0070] In step S3, if it is determined that a predetermined period has not elapsed since the tool was replaced (No in S3), CPU1 executes a third state estimation process (hereinafter referred to as the "post-replacement state estimation process") S7. Details of the post-replacement state estimation process S7 will be described later.

[0071] [2-3. Normal state estimation process S5] Figure 9 is a flowchart illustrating the normal state estimation process S5 shown in Figure 8.

[0072] In the normal state estimation process S5, CPU1 executes the workpiece thickness estimation process S50, the punch wear amount estimation process S51, and the die wear amount estimation process S52 in that order. This order is used because, generally, the workpiece thickness changes each time the workpiece is replaced, while punch wear and die wear change more slowly than the workpiece thickness, so workpiece thickness is estimated with priority over punch wear and die wear. Furthermore, the punch wear amount estimation process S51 is executed before the die wear amount estimation process S52 because the progression of punch wear is faster than the progression of die wear, so the punch wear amount is estimated with priority over die wear.

[0073] In the normal state estimation process S5, the clearance value of the state data 22 is fixed to the value estimated in the previous machining state estimation process. The reason for fixing the clearance is that in the normal state estimation process S5, where a predetermined period has elapsed since tool replacement or grinding, the clearance does not change at all or hardly at all even if press working is repeated.

[0074] Figure 10 is a flowchart illustrating the workpiece thickness estimation process S50 shown in Figure 9. In the workpiece thickness estimation process S50, the CPU 1 first executes the reference waveform generation process S501 corresponding to the state data.

[0075] Figure 11 is a flowchart illustrating the reference waveform generation process S501 corresponding to the state data in Figure 10. First, CPU 1 obtains a unit waveform corresponding to the parameter value of the state data 22 for each region from the waveform library 23 (S5010).

[0076] Next, the area waveform for each area is generated by multiplying each unit waveform by the area length (S5011).

[0077] Next, CPU1 generates a reference waveform that represents the load over the entire length of the punched-out contour by combining all the area waveforms (S5012). Combining multiple waveforms means, for example, taking the sum of multiple waveforms.

[0078] Returning to Figure 10, CPU1 calculates the degree of agreement between the reference waveform corresponding to the state data 22 generated in step S501 and the measured waveform acquired in step S1 (S502).

[0079] Here, the degree of agreement is an indicator that shows the degree of agreement between two waveforms. The degree of agreement can be, for example, the cosine similarity, Euclidean distance, or Manhattan distance between two waveforms during the punching period. CPU1 may calculate a loss instead of the degree of agreement, which is an indicator that shows the degree of mismatch between the two waveforms. Both the degree of agreement and the degree of mismatch are examples of "similarity," which is an indicator that shows the degree of similarity between two waveforms.

[0080] Next, CPU1 determines whether the loop processing in the work thickness estimation process S50 has converged (completed) (S503). Convergence means that all candidate values ​​that can be selected based on predetermined selection rules have been set in all areas of the provisional state data. In step S503, CPU1 makes a convergence determination by determining whether all candidate values ​​for work thickness have been set as work thicknesses in areas A1 to A8 of the provisional state data.

[0081] If CPU1 determines in step S503 that the loop processing in work thickness estimation process S50 has not converged (No in S503), it executes step S504. If it determines that it has converged (Yes in S503), it terminates work thickness estimation process S50.

[0082] In step S504, CPU1 prepares temporary state data by modifying the state data 22 for each area so that the workpiece thickness is set to one of the candidate values ​​for the workpiece thickness (S504). In step S504, the other parameters of the temporary state data, namely the punch wear amount, die wear amount, and clearance, are fixed to the punch wear amount, die wear amount, and clearance that were estimated in the previous step.

[0083] Next, CPU1 executes the reference waveform generation process S505 corresponding to the temporary state data. Figure 12 is a flowchart illustrating the reference waveform generation process S505 corresponding to the temporary state data in Figure 10. Compared to the reference waveform generation process S501 corresponding to the state data in Figure 11, the reference waveform generation process S505 corresponding to the temporary state data includes step S5050 instead of step S5010.

[0084] In the reference waveform generation process S505 corresponding to the provisional state data in Figure 12, the CPU 1 first obtains a unit waveform corresponding to the parameter value of the provisional state data for each region from the waveform library 23 (S5050). Subsequent steps S5011 and S5012 are the same as the reference waveform generation process S501 corresponding to the state data in Figure 11.

[0085] Returning to Figure 10, CPU1 calculates the degree of agreement between the reference waveform corresponding to the provisional state data generated in step S505 and the measured waveform acquired in step S1 (S506).

[0086] Next, CPU1 determines whether the degree of match calculated in step S504 has increased compared to the degree of match calculated in the most recent step S502 (S507). If CPU1 determines that the degree of match has increased (Yes in S507), it proceeds to step S508. If it determines that the degree of match has not increased (No in S507), it returns to step S503.

[0087] In step S508, CPU1 updates state data 22 so that the temporary state data prepared in step S504 becomes state data 22 (S508). After completing step S508, CPU1 returns to step S501.

[0088] As described above, in step S503, if CPU1 determines that the loop processing in work thickness estimation processing S50 has converged (Yes in S503), it finishes work thickness estimation processing S50 and executes punch wear amount estimation processing S51 (see Figure 9). In the above example, CPU1 finishes work thickness estimation processing S50 when it has completed all loops in which the work thickness in the provisional state data areas A1 to A8 has been set to 46 μm, 48 μm, 50 μm, 52 μm, and 54 μm.

[0089] Figure 13 is a flowchart illustrating the punch wear amount estimation process S51 shown in Figure 9. In the punch wear amount estimation process S51, the CPU 1 first executes a reference waveform generation process S501 (see Figure 11) corresponding to the state data. Next, the CPU 1 calculates the degree of agreement between the reference waveform corresponding to the state data 22 generated in step S501 and the measured waveform acquired in step S1 (S512).

[0090] Next, CPU1 determines whether the loop processing in punch wear amount estimation process S51 has converged (S513). That is, CPU1 determines whether all candidate values ​​for punch wear amount that are greater than the punch wear amount estimated in the previous machining state estimation process have been set in each area of ​​the provisional state data.

[0091] If CPU1 determines in step S513 that the loop processing in punch wear amount estimation process S51 has not converged (No in S513), it executes step S514. If it determines that it has converged (Yes in S513), it terminates punch wear amount estimation process S51.

[0092] In step S514, CPU1 prepares temporary state data by changing the state data 22 for each area so that the punch wear amount is set to a value greater than the punch wear amount estimated in the previous step (S514). In the example above, if the punch wear amount estimated in the previous step was 4 μm, CPU1 sets the punch wear amount in the temporary state data to one of 6 μm, 8 μm, 10 μm, or 12 μm.

[0093] Next, CPU1 executes the reference waveform generation process S505 corresponding to the temporary state data. CPU1 calculates the degree of agreement between the reference waveform corresponding to the temporary state data generated in step S505 and the measured waveform acquired in step S1 (S516).

[0094] CPU1 determines whether the degree of match calculated in step S516 has increased compared to the degree of match calculated in the most recent step S512 (S517). If CPU1 determines that the degree of match has increased (Yes in S517), it proceeds to step S518. If it determines that the degree of match has not increased (No in S517), it returns to step S513.

[0095] In step S518, CPU1 updates the state data 22 so that the temporary state data prepared in step S514 becomes the state data 22 (S518). After completing step S518, CPU1 returns to step S501.

[0096] Figure 14 is a flowchart illustrating the die wear amount estimation process S52 shown in Figure 9. In the die wear amount estimation process S52, the CPU 1 first executes a reference waveform generation process S501 (see Figure 11) corresponding to the state data. Next, the CPU 1 calculates the degree of agreement between the reference waveform corresponding to the state data 22 generated in step S501 and the measurement waveform acquired in step S1 (S522).

[0097] Next, CPU1 determines whether the loop processing in die wear amount estimation process S52 has converged (S523). That is, CPU1 determines whether all candidate values ​​for die wear amount that are greater than the die wear amount estimated in the previous machining state estimation process have been set in each area of ​​the provisional state data.

[0098] If CPU1 determines that the loop processing in die wear amount estimation process S52 has not converged (No in S523), it executes step S524. If it determines that it has converged (Yes in S523), it terminates die wear amount estimation process S52.

[0099] In step S524, CPU1 prepares temporary state data by changing the state data 22 for each area so that the die wear amount is set to a value greater than the die wear amount estimated in the previous step (S524).

[0100] Next, CPU1 executes the reference waveform generation process S505 corresponding to the temporary state data. CPU1 calculates the degree of agreement between the reference waveform corresponding to the temporary state data generated in step S505 and the measured waveform acquired in step S1 (S526).

[0101] CPU1 determines whether the degree of match calculated in step S526 has increased compared to the degree of match calculated in the most recent step S522 (S527). If CPU1 determines that the degree of match has increased (Yes in S527), it proceeds to step S528. If it determines that the degree of match has not increased (No in S527), it returns to step S523.

[0102] In step S528, CPU1 updates state data 22 so that the temporary state data prepared in step S524 becomes state data 22 (S528). After completing step S528, CPU1 returns to step S501.

[0103] As described above, in the normal state estimation process S5, the CPU1 estimates state data 22. The estimated state data 22 identifies the punch wear amount P1~P8, die wear amount D1~D8, clearance C1~C8, and workpiece thickness T shown in Figure 7. For the first area A1, the punch wear amount P1, die wear amount D1, clearance C1, and workpiece thickness T are identified. In this way, the machining state estimation device 100 can estimate the parameters for each area.

[0104] [2-4. Post-polishing state estimation process S6] Figure 15 is a flowchart illustrating the processing flow of the post-polishing state estimation process S6 shown in Figure 8. In the post-polishing state estimation process S6, the processing performed differs depending on whether the polished tool is a punch, a die, or both.

[0105] For example, CPU1 determines whether both the punch and the die have been polished (S61). In the example above, CPU1 determines whether it has received both a die polishing signal indicating that the die has been polished and a punch polishing signal indicating that the punch has been polished. If CPU1 determines that both the punch and the die have been polished (Yes in S61), it proceeds to step S62; otherwise (No in S61), it proceeds to step S64.

[0106] In step S64, CPU1 determines whether the punch has been polished or not. If CPU1 determines that the punch has been polished (Yes in S64), it proceeds to step S65; otherwise (No in S64), it proceeds to step S66. In other words, if both the punch and the die have been polished, step S62 is executed; if only the punch has been polished, step S65 is executed; and if only the die has been polished, step S66 is executed.

[0107] In step S62, CPU1 sets the punch wear amount and die wear amount to the initial value of 0 μm. With the punch wear amount and die wear amount fixed in this way, CPU1 executes the clearance estimation process (hereinafter referred to as the "clearance estimation process after polishing") S63 and the workpiece thickness estimation process S50. Instead of the example in Figure 15, the clearance estimation process after polishing S63 may be executed after the workpiece thickness estimation process S50. Details of the clearance estimation process after polishing S63 will be described later.

[0108] If it is determined in step S64 that the punch has been polished (Yes in S64), the CPU1 sets the punch wear amount to the initial value of 0 μm (S65), and then executes the post-polishing clearance estimation process S63, the workpiece thickness estimation process S50, and the die wear amount estimation process S52. Instead of the example in Figure 15, the post-polishing clearance estimation process S63 may be executed after the workpiece thickness estimation process S50 and the die wear amount estimation process S52.

[0109] If it is determined in step S64 that the punch has not been polished (No in S64), the CPU1 sets the die wear amount to the initial value of 0 μm (S66), and then executes the post-polishing clearance estimation process S63, the workpiece thickness estimation process S50, and the punch wear amount estimation process S51. Instead of the example in Figure 15, the post-polishing clearance estimation process S63 may be executed after the workpiece thickness estimation process S50 and the punch wear amount estimation process S51.

[0110] Figure 16 is a flowchart illustrating the clearance estimation process S63 after polishing, as shown in Figure 15. In the clearance estimation process S63 after polishing, CPU1 first executes a reference waveform generation process S501 (see Figure 11) corresponding to the state data. Next, CPU1 calculates the degree of agreement between the reference waveform corresponding to the state data 22 generated in step S501 and the measurement waveform acquired in step S1 (S632).

[0111] Next, CPU1 determines whether the loop processing in the clearance estimation process S63 after polishing has converged (S633). That is, CPU1 determines whether all candidate clearance values ​​that fall within a predetermined range from the clearance estimated in the previous machining state estimation process have been set in the provisional state data.

[0112] If CPU1 determines that the loop processing in the clearance estimation process S63 after polishing has not converged (No in S633), it executes step S634. If it determines that it has converged (Yes in S633), it terminates the clearance estimation process S63 after polishing.

[0113] In step S634, CPU1 prepares temporary state data by modifying state data 22 to set the clearance to a value within a predetermined range from the previously estimated clearance (S634). For example, if the previously estimated clearance was 5 μm, CPU1 sets the clearance in the temporary state data to a value within ±1 μm of 5 μm, i.e., 4 μm or 6 μm. The reason for limiting the range of clearance change to a predetermined range is that, unlike when the tool is replaced, it has been found that the clearance hardly changes even when the tool is ground.

[0114] Next, CPU1 executes the reference waveform generation process S505 corresponding to the temporary state data. CPU1 calculates the degree of agreement between the reference waveform corresponding to the temporary state data generated in step S505 and the measured waveform acquired in step S1 (S636).

[0115] CPU1 determines whether the degree of match calculated in step S636 has increased compared to the degree of match calculated in the most recent step S632 (S637). If CPU1 determines that the degree of match has increased (Yes in S637), it proceeds to step S638. If it determines that the degree of match has not increased (No in S637), it returns to step S633.

[0116] In step S638, CPU1 updates the state data 22 so that the temporary state data prepared in step S634 becomes the state data 22 (S638). After completing step S638, CPU1 returns to step S501.

[0117] [2-5. State estimation process after exchange S7] Figure 17 is a flowchart illustrating the state estimation process S7 after the exchange shown in Figure 8.

[0118] In the post-replacement state estimation process S7, the CPU1 first sets the punch wear amount and die wear amount to the initial value of 0 μm (S62). Next, the CPU1 executes the workpiece thickness estimation process S50.

[0119] Next, CPU1 executes a reference waveform generation process S501 (see Figure 11) corresponding to the state data. Next, CPU1 calculates the degree of agreement between the reference waveform corresponding to the state data 22 generated in step S501 and the measured waveform acquired in step S1 (S72).

[0120] Next, CPU1 determines whether the loop processing in the state estimation process S7 after the exchange has converged (S73). That is, CPU1 determines whether all candidate clearance values ​​have been set in the provisional state data.

[0121] If CPU1 determines that the loop processing in the post-replacement state estimation process S7 has not converged (No in S73), it executes step S74. If it determines that it has converged (Yes in S73), it terminates the post-replacement state estimation process S7.

[0122] In step S74, CPU1 prepares temporary state data by modifying state data 22 to set the clearance to one of the candidate clearance values ​​(S74).

[0123] Next, CPU1 executes the reference waveform generation process S505 corresponding to the provisional state data. CPU1 calculates the degree of agreement between the reference waveform corresponding to the provisional state data generated in step S505 and the measured waveform acquired in step S1 (S76).

[0124] CPU1 determines whether the degree of agreement calculated in step S76 has increased compared to the degree of agreement calculated in the most recent step S72 (S77). If CPU1 determines that the degree of agreement has increased (Yes in S77), it proceeds to step S78; if it determines that the degree of agreement has not increased (No in S77), it returns to step S73.

[0125] In step S78, CPU1 updates the state data 22 so that the temporary state data prepared in step S74 becomes the state data 22 (S78). After completing step S78, CPU1 returns to step S501.

[0126] The machining state estimation device 100 may notify the user if, in the estimated state data 22, the punch wear amount or die wear amount is above a predetermined threshold, and / or the clearance is not within a predetermined range. This allows the user to perform maintenance such as changing tools. Such notification may be performed by means of, for example, lighting or flashing an LED in red, generating a warning sound from a speaker, or displaying the state data 22 on a display.

[0127] [3. Effects, etc.] As described above, the processing state estimation device 100 according to this embodiment comprises a storage device 2 and a CPU 1, which is an example of a processor. The storage device 2 stores state parameters that define the processing state of the press machine 50, a unit waveform, and contour parameters. The unit waveform corresponds to the state parameter. The contour parameter defines the length of a plurality of areas obtained by dividing the punching contour by the press machine 50. The CPU 1 acquires a measurement waveform that shows the measurement result of the processing load by the press machine 50 (S1). The CPU 1 generates a reference waveform related to the processing load based on the unit waveform and contour parameters (S501, S505). The CPU 1 determines the degree of agreement between the reference waveform and the measurement waveform (S502, S506). Based on the determined degree of agreement, the CPU 1 estimates the processing state in each of the plurality of areas.

[0128] With this configuration, by estimating the processing state in each of the multiple regions obtained by dividing the punched contour, the processing state by the press machine 50 can be estimated with greater accuracy than in the conventional technology. For example, partial wear of the punch 73 and die 63 can be detected.

[0129] The state parameter may define the processing state per predetermined unit length of the punched contour. In this case, each of the multiple unit waveforms corresponds to each combination of the state parameter per predetermined unit length of the punched contour. In the process of generating the reference waveform, CPU1 generates a region waveform for each region relating to the processing load by multiplying the unit waveform for each region by the ratio of the length of the region defined in the contour parameter to the unit length (S5011). CPU1 generates a reference waveform relating to the processing load over the entire length of the punched contour by synthesizing the region waveforms for each region (S5012). For example, CPU1 generates a reference waveform relating to the processing load over the entire length of the punched contour by calculating the sum of the region waveforms for each region.

[0130] This configuration allows for more accurate estimation of the processing state by the press machine 50 than with conventional technology.

[0131] CPU1 may search for a reference waveform that has the greatest degree of agreement with the measured waveform, and determine the state parameters corresponding to the unit waveform which is the basis of the searched reference waveform as estimated parameters that represent the machining state of the measured waveform at the time of measurement (S5).

[0132] Conventionally, there is a known technique that determines a measurement waveform to be normal if it falls within a predetermined range between a set upper and lower limit, and abnormal if it falls outside that range. However, with conventional techniques, if the predetermined range is set too wide, it cannot detect abnormalities in the device such as tool wear, and if it is set too narrow, it may determine that the device is abnormal even though it is functioning normally. In contrast, the machining state estimation device 100 according to this embodiment, which searches for a reference waveform, can estimate the machining state with greater accuracy than conventional techniques.

[0133] In the process of searching for a reference waveform, CPU1 may sequentially change state parameters within a predetermined range based on an estimated parameter set already determined by CPU1, in order to search for a reference waveform that has the greatest degree of agreement with the measured waveform.

[0134] This configuration allows for a more accurate estimation of the processing state by performing a search based on the above criteria. Furthermore, it reduces the computational cost of estimation compared to a configuration without these criteria.

[0135] The state parameter may include a clearance parameter that defines the clearance of the press machine 50, and the estimated parameter may include an estimated clearance parameter that was estimated as the clearance parameter at the time of measurement of the measurement data.

[0136] This configuration allows for more accurate estimation of clearance parameters than conventional techniques.

[0137] The state parameter may include a punch wear parameter that defines the degree of wear of the punch 73 of the press machine 50, and the estimated parameter may include an estimated punch wear parameter that is estimated as the punch wear parameter at the time of measurement of the measurement data.

[0138] This configuration allows for a more accurate estimation of the wear amount of the punch 73 than conventional techniques.

[0139] In the process of searching for a reference waveform, CPU1 may sequentially change the punch wear parameter within a range of values ​​greater than or equal to the estimated punch wear parameter to search for a reference waveform that maximizes the degree of agreement with the measured data.

[0140] With this configuration, the amount of wear on the punch 73 can be estimated with greater accuracy by changing the punch wear parameter under the condition that it is greater than or equal to an already estimated value and searching for a reference waveform.

[0141] When CPU1 receives a signal indicating that the punch 73 has been replaced or polished, it may set the estimated punch wear parameter to an initial value.

[0142] This configuration allows for a more accurate estimation of the wear amount of the punch 73. Furthermore, since the estimated punch wear parameters are set to initial values, the computational cost required to search for and estimate these parameters can be reduced.

[0143] The state parameter may include a die wear parameter that defines the degree of wear of the die 63 of the press machine 50, and the estimated parameter may include an estimated die wear parameter that is estimated as the die wear parameter at the time of measurement of the measurement data.

[0144] This configuration allows for a more accurate estimation of the wear amount of the die 63 than with conventional technology.

[0145] In the process of searching for a reference waveform, CPU1 may sequentially change the die wear parameter within a range of values ​​greater than or equal to the estimated die wear parameter to search for a reference waveform that maximizes the degree of agreement with the measured data.

[0146] With this configuration, the amount of wear on the die 63 can be estimated with greater accuracy by changing the die wear parameter under the condition that it is greater than or equal to an already estimated value and searching for a reference waveform.

[0147] When CPU1 receives a signal indicating that die 63 has been replaced or polished, it may set the estimated die wear parameter to an initial value.

[0148] This configuration allows for a more accurate estimation of die 63 wear. Furthermore, since the estimated die wear parameters are set to initial values, the computational cost required to search for and estimate these parameters can be reduced.

[0149] The multiple parameters may further include a work thickness parameter that defines the thickness of the workpiece 80 processed by the press machine 50. In the process of searching for a reference waveform, the CPU 1 may sequentially change the work thickness parameter to search for a reference waveform that has the greatest degree of agreement with the measured waveform.

[0150] This configuration allows for further estimation of the thickness of the workpiece 80.

[0151] (Modification 1 of the first embodiment) The inventors have gained the following insights regarding clearance: The relative position of the punch 73 to the die 63 is determined only after the tool is assembled into the press machine 50. Not only are there machining errors in the tool, but assembly errors can also be added during tool assembly, so the measured clearance tends to deviate from the design clearance. This assembly error is a deviation from the design value of the relative position of the punch 73 to the die 63, and can therefore be observed as a clearance bias.

[0152] In the example shown in Figure 6, the measured clearance in the fourth area A4 is greater than the design clearance. As shown in Figure 5, the eighth area A8 is located opposite the fourth area A4 in the depth direction, so the measured clearance in the eighth area A8 correlates with the measured clearance in the fourth area A4. That is, in correspondence with the measured clearance being greater than the design clearance in the fourth area A4, the measured clearance in the eighth area A8 is smaller than the design clearance. Furthermore, the absolute value of the difference between the measured clearance and the design clearance in the fourth area A4 is approximately equal to the absolute value of the difference between the measured clearance and the design clearance in the eighth area A8.

[0153] Such correlation information of clearances between areas may be included in the state data 22. In this case, the contour parameters of the state data 22 include clearance correlation information indicating whether the clearance of one area correlates with the clearance of another area. If the state data 22 contains clearance correlation information indicating that the clearance of one area correlates with the clearance of another area, the CPU 1 uses the clearance correlation information in step S74, which prepares the provisional state data shown in Figure 17.

[0154] For example, if the punched-out outline is a rounded rectangle as shown in Figure 5, the second area A2 and the sixth area A6 are opposite sides of the rectangle, so the sum of the clearance C2 of the second area A2 (see Figure 7) and the clearance C6 of the sixth area A6 is approximately constant. For example, if the punch 73 is biased to the left relative to the paper in Figure 5, C2 decreases while C6 increases. Thus, with respect to the bias in clearance, it can be said that C2 + C6 is approximately constant. Similarly, C1 + C5, C3 + C7, and C4 + C8 are also approximately constant.

[0155] Using this clearance correlation information, CPU1 sequentially changes the clearance of the provisional state data in the post-exchange state estimation process S7 shown in Figure 17, changing the clearance of other areas according to the amount of change applied to the clearance of one area. This reduces the number of cases for clearance changes, thereby reducing the processing volume and processing load of the post-exchange state estimation process S7.

[0156] (Modification 2 of the first embodiment) The contour parameters of the state data 22 shown in Figure 7 indicate whether the shape of areas A1 to A8 is an arc or a curve R, or a straight line S. It is known that wear of the punch 73 and die 63 progresses faster in the curve R portion than in the straight line S portion.

[0157] Therefore, in this modified example, in the punch wear estimation process S51 shown in Figure 9, CPU1 estimates the punch wear amount in the curved R portion more preferentially than the punch wear amount in the straight S portion, based on the contour parameters of the state data 22. Similarly, in this modified example, in the die wear estimation process S52 shown in Figure 9, CPU1 estimates the die wear amount in the curved R portion more preferentially than the die wear amount in the straight S portion.

[0158] For example, CPU1 fixes the punch wear amount in areas where the punching contour is straight to the punch wear amount estimated in the previous machining state estimation process. Then, in the provisional state data, CPU1 sequentially changes the punch wear amount in areas where the punching contour is curved within a value greater than or equal to the previously estimated punch wear amount, and searches for a reference waveform that has the greatest degree of agreement with the measured waveform. CPU1 updates the state data 22 so that the punch wear amount in the area where the punching contour is curved in the provisional state data, which corresponds to the searched reference waveform, becomes the punch wear amount in that area in the state data 22.

[0159] Next, CPU1 fixes the punch wear amount in the area where the punching contour is curved to the value specified in the updated state data 22. Then, in the provisional state data, CPU1 sequentially changes the punch wear amount in the area where the punching contour is straight within a value greater than or equal to the previously estimated punch wear amount, and searches for a reference waveform that has the greatest degree of agreement with the measured waveform. CPU1 updates the state data 22 so that the punch wear amount in the area where the punching contour is straight in the provisional state data, which corresponds to the searched reference waveform, becomes the punch wear amount in the corresponding area in the state data 22.

[0160] The process for prioritizing the estimation of die wear in the curved R portion over the die wear in the straight S portion is the same as described above.

[0161] (Second Embodiment) Figure 18 is a table showing an example of state data 222 in the processing state estimation apparatus 100 according to the second embodiment of this disclosure. Compared with the state data 22 in Figure 7, in the state data 222, the eighth area A8 is subdivided into two sub-areas A8-1 and A8-2.

[0162] Thus, each area of ​​the state data 222 can be subdivided into multiple sub-areas. Areas A1 to A7 other than the eighth area A8 may be subdivided, or all areas may be subdivided. By subdividing the areas, the processing state estimation device 100 can estimate the processing state in more detail of the punched contour, and can improve the accuracy of the estimation, such as detecting partial wear.

[0163] Area subdivision is performed, for example, by the user specifying the area to be subdivided and how many subdivisions to make. Specifically, for example, when a subdivision instruction signal for specifying subdivision by the user is input to the CPU1 via the input interface 3, the CPU1 performs the subdivision.

[0164] Alternatively, the subdivision of a region may be performed when the amount of punch wear or die wear in that region in the status data 222 exceeds a predetermined threshold. Specifically, for example, if the amount of punch wear or die wear in that region in the status data 222 exceeds a predetermined threshold, the CPU 1 issues a subdivision instruction signal or flag. The CPU 1 receives the subdivision instruction signal it issued as input and uses this input as a trigger to perform subdivision. By performing subdivision when the amount of punch wear or die wear exceeds a predetermined threshold, it is possible to accurately detect areas where abnormal wear is progressing.

[0165] For the subdivided sub-regions A8-1 and A8-2, unlike the normal state processing S5 in the first embodiment shown in Figure 9, the CPU1 may perform clearance estimation processing. The clearance estimation processing is the same as the clearance estimation processing S63 after polishing. Alternatively, unlike the clearance estimation processing S63 after polishing, the clearance estimation processing may perform a process to prepare temporary state data in which the clearance of the state data 22 is set to a value greater than the previously estimated value, instead of step S634 in Figure 16.

[0166] Furthermore, in this embodiment, the CPU1 may prioritize estimating the punch wear amount and die wear amount in the subdivided sub-regions A8-1 and A8-2 over the punch wear amount and die wear amount in the undivided portion. Since the subdivided sub-regions A8-1 and A8-2 are areas where abnormal wear is expected to be progressing, the machining state is estimated in these areas with priority over the undivided portion.

[0167] Furthermore, in this embodiment, similar to Modification 2 of the first embodiment, the CPU1 may prioritize estimating the punch wear amount and die wear amount in the curved R portion over the punch wear amount and die wear amount in the straight S portion.

[0168] As described above, CPU1 selects at least one of the multiple areas A1 to A8 and subdivides the selected area into multiple sub-areas based on a subdivision instruction signal containing information for further subdividing the selected area into multiple sub-areas. In the process of estimating the processing state, CPU1 estimates the processing state in each of the areas A1 to A8 other than the selected area, and also estimates the processing state in each of the multiple sub-areas.

[0169] This configuration allows for the estimation of the processing state at even finer details of the punched-out contour, enabling more accurate estimation of the processing state.

[0170] (Other embodiments) As described above, the above embodiments have been explained as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited to these embodiments and can be applied to embodiments that have been modified, replaced, added, or omitted as appropriate. Therefore, other embodiments will be illustrated below.

[0171] (Other Embodiment 1) For example, in the first embodiment, an example was described in which the state data 22 includes punch wear amount, die wear amount, clearance, and workpiece thickness as parameters (see Figure 7), and the CPU 1 estimates these four parameters. However, the machining state estimation device according to the present disclosure may be configured to estimate at least one of the above parameters. For example, even a machining state estimation device configured to estimate only clearance can estimate the clearance of multiple areas obtained by dividing the punched contour, and can estimate the clearance with greater accuracy than conventional methods.

[0172] (Another Embodiment 2) Furthermore, although the above embodiment describes an example in which the CPU1 executes a reference waveform generation process S501 corresponding to state data, the disclosure is not limited thereto. For example, reference waveforms corresponding to all combinations of areas A1 to A8 and parameters may be calculated in advance by the CPU1 or an external arithmetic unit, and all calculated reference waveforms may be linked to each combination of areas A1 to A8 and parameters and stored in the storage device 2 in advance.

[0173] In this case, instead of step S502 in Figure 10, the CPU 1 calculates the degree of agreement between the reference waveform stored in the memory device 2 and the measured waveform acquired in step S1, and identifies the reference waveform with the highest degree of agreement. Since the identified reference waveform is associated with combinations of areas A1 to A8 and parameters, the amount of wear, clearance, and other parameters for each area can be estimated from the identified reference waveform.

[0174] With this configuration, since CPU1 does not need to generate multiple reference waveforms in real time, the processing load and processing time of CPU1 can be reduced. [Industrial applicability]

[0175] This disclosure is applicable to press machines. [Explanation of Symbols]

[0176] 2 Storage device 3. Input Interface 4 Output Interfaces 11. Load sensor 21 Programs 22,222 status data 23 Waveform Library 50 Press Machines 51 Bolster 52 slides 61 Die Backing Plate 62 Die Plates 63 Die 71 Punch backing plate 72 Punch Plates 73 punches 74 Stripper Plate 80 Work 100 Processing state estimation device

Claims

1. Equipped with a memory device and a processor, The aforementioned storage device is Parameters that define the processing state of the press machine, Reference data corresponding to the aforementioned parameters, The system stores area shape information that defines the lengths of multiple areas obtained by dividing the punched-out contour by the press machine, The aforementioned processor, Measurement data showing the measurement results of the processing load by the aforementioned press machine is obtained. Based on the aforementioned reference data and the area shape information, comprehensive reference data relating to the processing load is generated. The similarity index, which is an indicator of the degree of similarity between the aforementioned comprehensive reference data and the aforementioned measurement data, is determined. Based on the determined similarity, the processing state in each of the plurality of areas is estimated. Processing state estimation device.

2. The aforementioned parameters define the processing state per predetermined unit length of the punched contour, The aforementioned reference data corresponds to the parameter per predetermined unit length of the punched contour, In the process of generating the integrated reference data, the processor, For each area, area data relating to the processing load is generated for each area by multiplying the reference data by the ratio of the length of the area to the unit length as defined in the area shape information. By combining the area data for each of the aforementioned areas, a comprehensive reference data relating to the processing load over the entire length of the punched-out contour is generated. The processing state estimation device according to claim 1.

3. The processing state estimation device according to claim 2, wherein the processor generates comprehensive reference data relating to the processing load over the entire length of the punched contour by calculating the sum of the area data for each of the areas.

4. The processor subdivides the specified area into a plurality of sub-areas based on a subdivision instruction signal that includes information for specifying at least one of the plurality of areas and further subdividing the specified area into a plurality of sub-areas. The processor, in the process of estimating the processing state, estimates the processing state in each of the regions other than the designated region among the plurality of regions, and estimates the processing state in each of the plurality of sub-regions. A processing state estimation device according to any one of claims 1 to 3.

5. The aforementioned processor, Search for the comprehensive reference data that has the greatest similarity to the aforementioned measurement data. The parameters corresponding to the reference reference data, which is the basis of the searched comprehensive reference data, are determined as estimated parameters representing the processing state of the measurement data at the time of measurement. A processing state estimation device according to any one of claims 1 to 4.

6. The processing state estimation device according to claim 5, wherein the processor, in the process of searching for the comprehensive reference data, sequentially changes the parameters within a predetermined range based on the estimation parameters already determined by the processor, and searches for comprehensive reference data that has the greatest similarity to the measurement data.

7. The aforementioned parameters include clearance parameters that define the clearance of the press machine, The estimated parameters include the estimated clearance parameters estimated as the clearance parameters at the time of measurement of the measurement data. The processing state estimation device according to claim 5 or 6.

8. The area shape information includes clearance correlation information indicating whether the clearance parameter of one area correlates with the clearance parameter of another area. If the clearance correlation information, which indicates that the clearance parameter of one area correlates with the clearance parameter of the other area, is included in the area shape information, the processor, when sequentially changing the clearance parameter in the process of searching the integrated reference data, changes the clearance parameter of the other area in accordance with the amount of change applied to the clearance parameter of the one area. The processing state estimation device according to claim 7.

9. The aforementioned parameters include punch wear parameters that define the degree of wear of the punch of the press machine, The estimated parameters include estimated punch wear parameters estimated as the punch wear parameters at the time of measurement of the measurement data, A processing state estimation device according to any one of claims 5 to 8.

10. The processing state estimation device according to claim 9, wherein the processor, in the process of searching for the comprehensive reference data, sequentially changes the punch wear parameter within a value greater than or equal to the estimated punch wear parameter to search for the comprehensive reference data that has the greatest similarity to the measurement data.

11. The area shape information includes information indicating whether the punched-out contour in each of the plurality of areas is straight or curved. The aforementioned processor, The punch wear parameter in the area where the punched-out contour is linear is fixed to the estimated punch wear parameter, and the punch wear parameter in the area where the punched-out contour is curved is sequentially changed within a value greater than or equal to the estimated punch wear parameter to search for a comprehensive reference data that has the maximum first similarity to the measured data. The punch wear parameter for the area where the punched-out contour is curved, corresponding to the overall reference data with the highest first similarity, is determined as the estimated punch wear parameter for the area where the punched-out contour is curved. The punch wear parameter in the area where the punched-out contour is curved is fixed to the estimated punch wear parameter in the area where the punched-out contour is curved, and the punch wear parameter in the area where the punched-out contour is straight is sequentially changed within a value greater than or equal to the estimated punch wear parameter to search for a comprehensive reference data that maximizes the second similarity with the measured data. The punch wear parameter for the area where the punched-out contour is linear, corresponding to the overall reference data with the highest second similarity, is determined as the estimated punch wear parameter for the area where the punched-out contour is linear. The processing state estimation device according to claim 9 or 10.

12. The machining state estimation device according to any one of claims 9 to 11, wherein the processor sets the estimated punch wear parameter to an initial value when it receives a signal indicating that the punch has been replaced or polished.

13. The aforementioned parameters include die wear parameters that define the degree of wear of the die of the press machine, The estimated parameters include estimated die wear parameters estimated as the die wear parameters at the time of measurement of the measurement data. A processing state estimation device according to any one of claims 5 to 12.

14. In the process of searching for the overall reference data, the processor sequentially changes the die wear parameter within a value greater than or equal to the estimated die wear parameter to search for the overall reference data that has the greatest similarity to the measurement data. The processing state estimation device according to claim 13.

15. The area shape information includes information indicating whether the punched-out contour in each of the plurality of areas is straight or curved. The aforementioned processor, The die wear parameter in the area where the punched-out contour is linear is fixed to the estimated die wear parameter, and the die wear parameter in the area where the punched-out contour is curved is sequentially changed within a value greater than or equal to the estimated die wear parameter to search for a comprehensive reference data that has the maximum third similarity to the measured data. The die wear parameter for the area where the punched-out contour is curved, corresponding to the comprehensive reference data with the maximum similarity of the third, is determined as the estimated die wear parameter for the area where the punched-out contour is curved. The die wear parameter in the area where the punched-out contour is curved is fixed to the estimated die wear parameter in the area where the punched-out contour is curved, and the die wear parameter in the area where the punched-out contour is straight is sequentially changed within a value greater than or equal to the estimated die wear parameter to search for a comprehensive reference data that maximizes the fourth similarity with the measurement data. The die wear parameter for the area where the punched-out contour is linear, corresponding to the composite reference data with the highest similarity of the fourth, is determined as the estimated die wear parameter for the area where the punched-out contour is linear. The processing state estimation device according to claim 13 or 14.

16. The machining state estimation device according to any one of claims 13 to 15, wherein the processor sets the estimated die wear parameter to an initial value when it receives a signal indicating that the die has been replaced or polished.

17. The parameter further includes a workpiece thickness parameter that defines the thickness of the workpiece processed by the press machine, In the process of searching for the aggregate reference data, the processor sequentially changes the workpiece thickness parameter to search for the aggregate reference data that has the greatest similarity to the measurement data. A processing state estimation device according to any one of claims 5 to 16.

18. The processor acquires measurement data showing the measurement results of the processing load by the press machine, The processor generates comprehensive reference data relating to the processing load based on reference reference data corresponding to parameters defining the processing state of the press machine and area shape information defining the lengths of multiple areas obtained by dividing the punched contour by the press machine. The processor performs the steps of determining a similarity score, which is an indicator of the degree of similarity between the aggregated reference data and the measurement data, The processor estimates the processing state in each of the plurality of regions based on the determined similarity, A method for estimating the processing state, including the method described above.

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