Degradation determination device, threshold value determination device, threshold value determination method, and recording medium

Abstract

A degradation determination device (1) includes an acquisition unit (10), a selection unit (40), a determination unit (50), and a degradation determination unit (31). The selection unit (40) selects, as an extraction range, a range containing the largest number of measurement values ​​among a plurality of ranges obtained by dividing a numerical range from a minimum value to a maximum value among a plurality of measurement values ​​contained in time series measurement data acquired by the acquisition unit (10) in a threshold determination mode for determining a threshold value. The determination unit (50) determines a threshold value based on the extraction range selected by the selection unit (40) or a plurality of measurement values ​​contained in the extraction range. The degradation determination unit (31) determines the degradation of the processing equipment (2) based on the time series measurement data acquired by the acquisition unit (10) and the threshold value determined by the determination unit (50) in a degradation determination mode for determining the degradation of the processing equipment (2).

Description

Technical Field

[0001] The present invention relates to a degradation determination device, a threshold value determination device, a threshold value determination method, and a threshold value determination program for determining degradation of processing equipment. Background Art

[0002] Processing equipment such as numerically controlled (NC) processing machines may experience degradation and failure of components such as instruments and parts. Patent Document 1 proposes a degradation detection technique that detects component degradation based on measurement values ​​output by sensors installed in the processing equipment.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-091414 Summary of the Invention

[0004] However, the technology described in Patent Document 1 uses a table to assign sensor output values ​​to numerically represent the degree of degradation. This table must be manually configured in advance. Therefore, the technology described in Patent Document 1 requires significant time and effort to pre-configure the degradation determination process.

[0005] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a degradation determination device capable of reducing the man-hours required for preliminary settings for degradation determination.

[0006] In order to solve the above-mentioned problems and achieve the purpose, the degradation determination device of the present invention includes an acquisition unit, a selection unit, a determination unit, and a degradation determination unit. The acquisition unit acquires time-series measurement data including multiple measurement values ​​output from a sensor that detects the state of the processing equipment while the processing equipment is processing the workpiece. The selection unit selects, as an extraction range, a range containing the largest number of measurement values ​​among multiple ranges obtained by dividing the numerical range from the minimum value to the maximum value among the multiple measurement values ​​contained in the time-series measurement data acquired by the acquisition unit in a threshold determination mode for determining the threshold. The determination unit determines the threshold based on the extraction range selected by the selection unit or the multiple measurement values ​​contained in the extraction range. In the degradation determination mode for determining the degradation of the processing equipment, the degradation determination unit determines the degradation of the processing equipment based on the time-series measurement data acquired by the acquisition unit and the threshold determined by the determination unit.

[0007] Effects of the Invention

[0008] According to the present invention, there is an effect of being able to save man-hours required for preliminary settings for degradation determination. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1This is a diagram showing an example of the configuration of a degradation determination device according to Embodiment 1 of the present invention.

[0010] Figure 2 This is a diagram showing the relationship between the extraction numerical value range and extraction time range selected by the degradation determination device according to the first embodiment, and the determination threshold value determined by the degradation determination device.

[0011] Figure 3 This is a diagram showing a specific configuration example of the degradation determination device according to the first embodiment.

[0012] Figure 4 This is a diagram for explaining the division process of the maximum numerical range performed by the division processing unit according to the first embodiment.

[0013] Figure 5 This is a diagram showing an example of changes in measurement values ​​output from the sensor during one cycle according to the first embodiment.

[0014] Figure 6 It will Figure 5 The maximum numerical range shown is divided into 18 ranges, and the number of measured values ​​included in each range is plotted.

[0015] Figure 7 This is a flowchart showing an example of processing performed by the processing unit of the degradation determination device according to the first embodiment.

[0016] Figure 8 This is a flowchart showing an example of threshold value determination processing performed by the processing unit of the degradation determination device according to the first embodiment.

[0017] Figure 9 This is a flowchart showing an example of determination target section determination processing performed by the processing unit of the degradation determination device according to the first embodiment.

[0018] Figure 10 This is a flowchart showing an example of extraction numerical value range selection processing performed by the processing unit of the degradation determination device according to the first embodiment.

[0019] Figure 11 This is a flowchart showing an example of degradation determination processing performed by the processing unit of the degradation determination device according to the first embodiment.

[0020] Figure 12 This is a flowchart showing an example of determination processing performed by the degradation determination unit of the degradation determination device according to the first embodiment.

[0021] Figure 13This is a diagram showing an example of the hardware configuration of the degradation determination device according to the first embodiment.

[0022] Figure 14 This is a diagram showing an example of the configuration of a degradation determination device according to Embodiment 2 of the present invention.

[0023] Figure 15 This is a diagram showing an example of the extraction numerical value range and the extraction time range selected by the degradation determination device according to the second embodiment.

[0024] Figure 16 This is a flowchart showing an example of threshold value determination processing performed by the processing unit of the degradation determination device according to the second embodiment.

[0025] Figure 17 This is a diagram showing an example of the configuration of a degradation determination device according to Embodiment 3 of the present invention.

[0026] Figure 18 This is a flowchart showing an example of comparison value determination processing performed by the processing unit of the degradation determination device according to the third embodiment.

[0027] Figure 19 This is a flowchart showing an example of comparison range selection processing performed by the degradation determination unit of the degradation determination device according to the third embodiment.

[0028] Figure 20 This is a flowchart showing an example of a determination process performed by the degradation determination unit of the degradation determination device according to the third embodiment. DETAILED DESCRIPTION

[0029] Hereinafter, a degradation determination device, a threshold value determination device, a threshold value determination method, and a threshold value determination program according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0030] Implementation method 1.

[0031] Figure 1 FIG. 1 is a diagram showing an example of the structure of a degradation determination device according to Embodiment 1 of the present invention. Figure 1 As shown, the degradation determination device 1 according to the first embodiment determines degradation of instruments or components constituting the processing equipment 2 based on time-series measurement data including a plurality of measurement values ​​at different measurement times output from a sensor 3 detecting the state of the processing equipment 2 .

[0032] The processing equipment 2 is, for example, a CNC machine that performs turning, milling, or drilling on a workpiece. Below, the processing equipment 2 is described as a CNC machine, but the processing equipment 2 is not limited to a CNC machine and may be other processing equipment.

[0033] The sensor 3 is, for example, a current sensor that repeatedly measures the instantaneous value of the current flowing through the servo motor of the processing equipment 2 at a preset cycle, and outputs time-series measurement data including a plurality of repeatedly measured instantaneous values ​​of the current as measurement values.

[0034] The degradation determination device 1 includes an acquisition unit 10, a processing unit 11, a communication unit 12, and a display unit 13. The processing unit 11 includes a data analysis unit 30 and a degradation determination unit 31.

[0035] The acquisition unit 10 acquires time-series measurement data output from the sensor 3 while the processing equipment 2 is performing processing on a workpiece (not shown). Furthermore, the acquisition unit 10 acquires motion data indicating the start or end of processing on the workpiece from the processing equipment 2. Hereinafter, the processing of the workpiece by the processing equipment 2 will be referred to simply as processing by the processing equipment 2 or processing.

[0036] When the operating mode is threshold determination mode, the data analysis unit 30 determines a threshold value used to determine degradation of the processing equipment 2, i.e., a determination threshold value, based on the time-series measurement data acquired by the acquisition unit 10 during one cycle of the processing. The threshold determination mode is an operating mode that determines the determination threshold value. Furthermore, the data analysis unit 30 determines the start and end of the processing based on the operating data acquired by the acquisition unit 10.

[0037] The duration of one cycle of processing is the period from the start of processing on the workpiece to its completion. Furthermore, when the processing equipment 2 performs multiple processing on the workpiece, the data analysis unit 30 determines a determination threshold for each processing and determines the start and end of each processing. Below, the duration of one cycle of processing may be referred to as one cycle period.

[0038] The data analysis unit 30 includes a selection unit 40 and a determination unit 50. The selection unit 40 divides the maximum numerical range (i.e., the numerical range from the minimum value to the maximum value) among the multiple measurement values ​​included in the time-series measurement data acquired by the acquisition unit 10 during one cycle in the threshold determination mode into multiple ranges, and selects the range containing the largest number of measurement values ​​among the divided multiple ranges as the extracted numerical range. The extracted numerical range is an example of an extracted range.

[0039] For example, in machining equipment 2, a cutting tool rotated by a servo motor processes a workpiece. In this case, at the moment the cutting tool, rotated by the servo motor, contacts the workpiece, a relatively high current flows through the servo motor for a short period of time due to the kinetic energy of the cutting tool. Subsequently, while the workpiece is continuously cut by the cutting tool, the load applied to the cutting tool fluctuates little, and the current flowing through the servo motor continues to fluctuate little.

[0040] The selection unit 40 selects, as the extraction numerical range, the range containing the largest number of measured values ​​among the multiple ranges obtained by dividing the maximum numerical range. Therefore, the numerical range in which the number of measured values ​​within the maximum numerical range is concentrated is selected as the extraction numerical range. In the above example, the numerical range in which the distribution of measured values ​​within the maximum numerical range is concentrated includes a plurality of measured values ​​output from the sensor 3 in a state where the current value flowing through the servo motor exhibits minimal change.

[0041] Furthermore, the selection unit 40 extracts as the extraction time range a time range within a cycle period in which a measured value exists within the extraction value range. In the above example, the extraction time range is a period in which the current flowing through the servo motor changes little. Alternatively, the selection unit 40 can extract as the extraction time range a time range within a cycle period in which a measured value exists within the extraction value range and the measured values ​​continuously fall within the extraction value range.

[0042] The decision unit 50 determines the determination threshold based on the extraction numerical value range selected by the selection unit 40 in the threshold determination mode. For example, the decision unit 50 determines the maximum value of the extraction numerical value range selected by the selection unit 40 as the determination threshold.

[0043] Figure 2 : is a diagram showing the relationship between the extraction value range and extraction time range selected by the degradation determination device according to the first embodiment and the determination threshold value determined by the degradation determination device. Figure 2 In the example, the vertical axis represents the magnitude of the measured value, and the horizontal axis represents time. Figure 2 In FIG. 1 , time t10 is the time when the processing of the processing equipment 2 starts, and time t20 is the time when the processing of the processing equipment 2 completes.

[0044] exist Figure 2 In the example shown, the selection unit 40 selects a numerical range where the number of distributions of measured values ​​is concentrated during one cycle as an extraction numerical range, and the maximum value of the selected extraction numerical range is determined by the determination unit 50 as a determination threshold.

[0045] Figure 1When the operation mode is the degradation determination mode for determining degradation of the processing equipment 2 , the degradation determination unit 31 shown determines degradation of the processing equipment 2 based on time-series measurement data including a plurality of measurement values ​​output from the sensor 3 and the determination threshold value determined by the determination unit 50 .

[0046] For example, the degradation determination unit 31 compares a plurality of measurement values ​​included in the time-series measurement data acquired by the acquisition unit 10 in the degradation determination mode and included in the extraction time range selected by the selection unit 40 with a determination threshold. The degradation determination unit 31 determines whether the number of measurement values ​​exceeding the determination threshold exceeds a predetermined number. The predetermined number is, for example, m times the number of measurement values ​​exceeding the determination threshold when the processing equipment 2 is operating normally. m is, for example, a number greater than 1.

[0047] For example, when machining with a cutting tool rotated by a servo motor, if the cutting tool or servo motor deteriorates, the current required to drive the servo motor increases. Therefore, the more severe the degradation of the cutting tool or servo motor, the larger the measured value becomes during the extraction time range, and the more often the value exceeds the determination threshold. The degradation determination unit 31 determines that the cutting tool or servo motor constituting the machining device 2 has deteriorated if the number of measured values ​​exceeding the determination threshold exceeds a predetermined number.

[0048] When the degradation determination unit 31 determines that degradation has occurred in the processing equipment 2, it can transmit information indicating degradation of the processing equipment 2 from the communication unit 12 to the terminal device 4 via the network, or display the information on the display unit 13. The terminal device 4 is a terminal device owned by the administrator of the processing equipment 2, such as a laptop computer or a tablet.

[0049] As described above, degradation determination device 1 automatically determines a determination threshold value while processing equipment 2 is processing a workpiece based on time-series measurement data, including multiple measurement values, output by sensor 3, which detects the state of processing equipment 2. Therefore, degradation determination device 1 eliminates the need for a human to observe the data output from sensor 3 and set the determination threshold value through trial and error, thus saving the time and effort required for pre-setting the determination threshold value.

[0050] Furthermore, the degradation determination device 1 can use measured values ​​output from the sensor 3 in a state where there is little variation in the measured values, for example, to determine the determination threshold and determine degradation based on the numerical range in which the distribution of measured values ​​within the maximum numerical range is concentrated. This allows for highly accurate determination of degradation of the processing equipment 2. Furthermore, the determination threshold can be determined based on measured values ​​suitable for determining degradation of the processing equipment 2 within a single cycle, and the measured values ​​used for the determination threshold are not limited to the above example.

[0051] Furthermore, the data analysis unit 30 of the degradation determination device 1 can also determine different determination thresholds for multiple periods within a single cycle. Furthermore, the data analysis unit 30 can also determine the determination thresholds using the aforementioned process using measurement values ​​for only a portion of a single cycle. The method for determining each determination threshold and the degradation determination method based on each determination threshold can be performed using the same process as the method for determining the determination threshold and the degradation determination method based on the determination threshold described above.

[0052] Next, the configuration of the degradation determination device 1 will be described in more detail. Figure 3 FIG. 1 is a diagram showing a specific configuration example of the degradation determination device according to the first embodiment. Figure 3 As shown, the acquisition unit 10 includes a time-series data acquisition unit 21 and a motion data acquisition unit 22 .

[0053] The time-series data acquisition unit 21 acquires time-series measurement data output from the sensor 3 in the threshold determination mode. The time-series measurement data includes a plurality of measurement values ​​output from the sensor 3 at different measurement times during a single cycle in the threshold determination mode. Furthermore, the time-series data acquisition unit 21 acquires time-series measurement data output from the sensor 3 in the degradation determination mode. The time-series measurement data includes a plurality of measurement values ​​output from the sensor 3 at different measurement times during a single cycle in the degradation determination mode.

[0054] The motion data acquisition unit 22 acquires the above-mentioned motion data from the processing equipment 2. The motion data output from the processing equipment 2 includes, for example, motion start data output at the start timing of processing and motion end data output at the end timing of processing.

[0055] Furthermore, time-series measurement data includes, in addition to the multiple measurement values ​​output from sensor 3 during a single cycle, information indicating the time at which each of the multiple measurement values ​​was measured. Furthermore, action start data may include information indicating the start time of a processing operation, and action end data may include information indicating the end time of a processing operation. In this case, the time-series measurement data may not be output from sensor 3 at a timing synchronized with the processing performed by processing equipment 2.

[0056] In the following description, sensor 3 is assumed to be a current sensor provided to the servo motor of processing equipment 2. However, sensor 3 is not limited to a current sensor provided to the servo motor of processing equipment 2. Any sensor that measures electrical characteristics whose magnitude changes in accordance with degradation of components of processing equipment 2 may be used. For example, if the voltage, power, current phase, or voltage phase supplied to a component of processing equipment 2 changes due to degradation of the component of processing equipment 2, sensor 3 may be a sensor that measures the voltage, power, current phase, or voltage phase.

[0057] like Figure 3 As shown, the selection unit 40 in the data analysis unit 30 includes a division processing unit 41 , a first calculation unit 42 , a second calculation unit 43 , a sufficiency determination unit 44 , a most frequently appearing range determination unit 45 , and a time range extraction unit 46 .

[0058] In the threshold determination mode, the segmentation processing unit 41 divides the maximum numerical range into segments k based on the time-series measurement data acquired by the acquisition unit 10 during a single cycle. K is an integer greater than or equal to 2. The maximum numerical range is the numerical range from the minimum value to the maximum value among the multiple measurement values ​​included in the time-series measurement data acquired by the acquisition unit 10 during a single cycle. For example, the segmentation processing unit 41 determines as the determination target range a segmented range in which the number of measurement values ​​is concentrated among the multiple segmented ranges obtained by dividing the maximum numerical range.

[0059] Figure 4 This is a diagram for explaining the division process of the maximum numerical range performed by the division processing unit according to the first embodiment. Figure 4 In the example, time t10 to t20 is one cycle period, and the maximum value range is from the minimum measured value x min To the maximum measured value x max The minimum measurement value x min The maximum measurement value x is the minimum value among the multiple measurement values ​​included in the time series measurement data acquired by the acquisition unit 10 during one cycle. maxIt is the maximum value among the multiple measurement values ​​included in the time series measurement data acquired by the acquisition unit 10 during one cycle. Figure 4 In the illustrated example, the measurement value output from the sensor 3 is the current value of the current flowing through the motor of the processing equipment 2 .

[0060] exist Figure 4 In the example shown, the maximum numerical range is divided into 6 divided ranges by the division processing unit 41. Figure 4 The number of measurement values ​​included in the third segment range from the top is the largest. In this case, the segmentation processing unit 41 Figure 4 The third segment range from the top is determined as the judgment target range.

[0061] The first calculation unit 42 calculates the average value μ and the standard deviation σ of the measurement values ​​in the determination target range based on the plurality of measurement values ​​included in the determination target range, for example, by performing operations according to the following equations (1) and (2). In the following equations (1) and (2), “x i " represents the measurement values ​​included in the judgment target range, and "n" represents the number of measurement values ​​included in the judgment target range.

[0062] [Formula 1]

[0063]

[0064]

[0065] The second calculation unit 43 calculates the first value x obtained by subtracting a value corresponding to the standard deviation σ from the average value μ. a and the second value x obtained by adding a value corresponding to the standard deviation σ to the mean value μ b The value corresponding to the standard deviation σ is, for example, a value h times the standard deviation σ. h is, for example, in the range of 0.5 to 1.5.

[0066] The sufficiency determination unit 44 determines whether the distribution of the plurality of measurement values ​​included in the determination target range satisfies a preset condition. For example, the sufficiency determination unit 44 determines whether the distribution of the plurality of measurement values ​​included in the determination target range satisfies a preset condition. mid Calculation is performed. Figure 4 In the case of the third segment range from the top, the central value AR mid is the maximum measured value x max3 Subtract the minimum measurement x min3 The value obtained by dividing the result by 2.

[0067] The sufficiency determination unit 44 determines the median value AR mid Is it greater than or equal to the first value x aand is less than or equal to the second value x b The sufficiency determination unit 44 determines the median value AR mid Greater than or equal to the first value x a and is less than or equal to the second value x b In the case of , it is determined that the distribution of the plurality of measured values ​​included in the determination target range satisfies a preset condition, and the determination target range is selected as the extraction numerical value range.

[0068] In the central value AR mid Not greater than or equal to the first value x a and is less than or equal to the second value x b In the case of the measurement value distribution in the determination target range, the range from the central value AR mid Since the range deviates significantly, the sufficiency determination unit 44 does not select the determination target range as the extraction numerical value range.

[0069] The most frequently occurring range determination unit 45 divides the maximum numerical range into multiple ranges using a division number p that is greater than the division number k for the divided ranges, and calculates the number of measured values ​​contained in each of the divided ranges, i.e., the number of measured values. P is an integer greater than k. The most frequently occurring range determination unit 45 determines the range with the largest number of measured values ​​among the divided ranges as the most frequently occurring range.

[0070] The sufficiency determination unit 44 determines the median value AR mid Greater than or equal to the first value x a and is less than or equal to the second value x b In the case of the most frequent appearance range determined by the most frequent appearance range determination unit 45, it is possible to determine whether the most frequent appearance range is greater than or equal to the first value x. a and is less than or equal to the second value x b The sufficiency determination unit 44 determines that the most frequent occurrence range is greater than or equal to the first value x a and is less than or equal to the second value x b In the case of , it is determined that the distribution of the plurality of measured values ​​included in the determination target range satisfies a preset condition, and the determination target range is selected as the extraction numerical value range.

[0071] In the most frequent range greater than or equal to the first value x a and is less than or equal to the second value x b In the case of , it is estimated that the distribution of the measured values ​​in the determination target range includes two or more peaks, so the sufficiency determination unit 44 determines that the most frequent range is greater than or equal to the first value x a and is less than or equal to the second value x b In the case of , the determination target range is not selected as the extraction numerical value range.

[0072] If the sufficiency determination unit 44 determines that the distribution of the multiple measured values ​​included in the determination target range is insufficient for a predetermined condition, the segmentation processing unit 41 increases the number of segments k of the numerical range and re-segments the maximum numerical range. The first calculation unit 42, the second calculation unit 43, the sufficiency determination unit 44, and the most frequently occurring range determination unit 45 repeatedly perform the above-described process on the segmented ranges re-segmented by the segmentation processing unit 41. This allows the selection unit 40 to accurately extract the segmented ranges in which the number of measured values ​​is concentrated among the multiple segmented ranges as the extracted numerical ranges. The segmented ranges in which the number of measured values ​​is concentrated have a small variation in the measured values ​​and a large number of measured values. Furthermore, the number of segments k may be a fixed value.

[0073] Figure 5 This is a diagram showing an example of changes in measurement values ​​output from the sensor during one cycle according to the first embodiment. Figure 5 The measured value shown is the current value flowing through the motor that drives the cutting tool for processing the workpiece in the processing equipment 2. Figure 5 In the example shown, the current rapidly increases at the beginning of the processing, then rapidly decreases, resulting in a period of minimal current change. During this period of minimal current change, the measured value changes minimally. In this case, degradation determination device 1 uses the most frequently occurring range of measured values, for example, as follows, to select an extraction value range.

[0074] Figure 6 It will Figure 5 The maximum numerical range shown is divided into 18 parts, and the number of measured values ​​included in each range is plotted. Figure 6 In the example shown, the range of measured values ​​from 6000 [A] to 8000 [A] is the most frequently occurring range. For example, let the range from 6000 [A] to 8000 [A] be included in the determination target range, and let the range from 6000 [A] to 8000 [A], i.e., the most frequently occurring range, be greater than or equal to the first value x. a and is less than or equal to the second value x b In this case, it is determined that the distribution of the plurality of measured values ​​included in the determination target range satisfies a predetermined condition, and the determination target range is selected as the extraction value range. Thus, the degradation determination device 1 can accurately extract the segmented range in which the number of measured values ​​is concentrated as the extraction value range.

[0075] In the threshold determination mode, the determination unit 50 determines the determination threshold based on the extraction value range selected by the selection unit 40. For example, if the measured value increases as the processing equipment 2 deteriorates, the determination unit 50 determines the maximum value of the extraction value range as the determination threshold. Alternatively, if the measured value decreases as the processing equipment 2 deteriorates, the determination unit 50 determines the minimum value of the extraction value range as the determination threshold.

[0076] Alternatively, the determination unit 50 can determine the judgment threshold based on the multiple measured values ​​included in the extracted numerical range. For example, if the measured value increases as the processing equipment 2 deteriorates, the determination unit 50 may determine the judgment threshold as a value obtained by multiplying the average value μ of the multiple measured values ​​included in the extracted numerical range by m. m is an integer greater than 1. Alternatively, if the measured value decreases as the processing equipment 2 deteriorates, the determination unit 50 may determine the judgment threshold as a value obtained by multiplying the average value μ of the multiple measured values ​​included in the extracted numerical range by 1 / m.

[0077] Next, a description will be given of the processing performed by the processing unit 11 of the degradation determination device 1 using a flowchart. Figure 7 This is a flowchart showing an example of processing performed by the processing unit of the degradation determination device according to the first embodiment. Figure 7 The processing shown is repeatedly executed by the processing unit 11 of the degradation determination device 1 .

[0078] like Figure 7 As shown, the processing unit 11 of the degradation determination device 1 determines whether the operation mode is the threshold value determination mode (step S10). The operation mode is set in the processing unit 11 of the degradation determination device 1 by, for example, input to an input unit (not shown) or a setting button (not shown).

[0079] When the processing unit 11 determines that the operation mode is the threshold value determination mode (step S10: Yes), it performs a threshold value determination process (step S11). The threshold value determination process in step S11 is Figure 8 The processing of steps S20 to S26 will be described later.

[0080] When the processing of step S11 is completed or when it is determined that the operation mode is not the threshold value determination mode (step S10 : No), the processing unit 11 determines whether the operation mode is the degradation determination mode (step S12 ).

[0081] When the processing unit 11 determines that the operation mode is the degradation determination mode (step S12: Yes), it performs degradation determination processing (step S13). The degradation determination processing in step S13 is Figure 11The processing of steps S50 and S51 shown in FIG. 1 is described later. When the processing of step S13 is completed, or when it is determined that the operation mode is not the degradation determination mode (step S12: No), the processing unit 11 ends. Figure 7 The processing shown.

[0082] Figure 8 1 is a flowchart showing an example of a threshold value determination process performed by the processing unit of the degradation determination device according to the first embodiment. Figure 8 As shown, the processing unit 11 of the degradation determination device 1 determines whether the processing by the processing equipment 2 has started (step S20). In step S20, when the acquisition unit 10 acquires the operation start data from the processing equipment 2, the processing unit 11 determines that the processing by the processing equipment 2 has started.

[0083] When the processing unit 11 of the degradation determination device 1 determines that the processing by the processing equipment 2 has started (step S20: Yes), it acquires the measured value from the sensor 3 via the acquisition unit 10 (step S21). Next, the processing unit 11 determines whether the processing by the processing equipment 2 is complete (step S22). In step S22, if the acquisition unit 10 acquires the operation completion data from the processing equipment 2, the processing unit 11 determines that the processing by the processing equipment 2 is complete.

[0084] When the processing unit 11 determines that the processing by the processing equipment 2 is not completed (step S22: No), it jumps to step S21 and repeatedly obtains measurement values ​​from the sensor 3 via the acquisition unit 10 until it determines that the processing by the processing equipment 2 is completed. Thus, the processing unit 11 obtains time series measurement data including multiple measurement values ​​output from the sensor 3 during one cycle of the processing in the threshold determination mode. When the processing unit 11 determines that the processing by the processing equipment 2 is completed (step S22: Yes), it performs the determination target interval determination process (step S23). The determination target interval determination process in step S23 is Figure 9 The processing of steps S30 to S32 will be described later.

[0085] After the processing unit 11 completes the determination target interval determination processing of step S23, it performs the extraction value range selection processing (step S24). The extraction value range selection processing in step S24 is Figure 10 The processing of steps S40 to S47 will be described later.

[0086] Next, the processing unit 11 extracts the time range in which the multiple measured values ​​included in the extraction value range selected by the extraction value range selection process exist as the extraction time range (step S25). In addition, the processing unit 11 performs a threshold determination process to determine a determination threshold based on the extraction value range selected by the extraction value range selection process (step S26).

[0087] In step S26, the decision unit 50 of the processing unit 11 can determine the maximum value of the extracted numerical range as the determination threshold, or the value obtained by multiplying the average value μ by m, if the measured value increases due to deterioration of the processing equipment 2. Furthermore, the decision unit 50 of the processing unit 11 can determine the minimum value of the extracted numerical range as the determination threshold, or the value obtained by multiplying the average value μ by 1 / m, if the measured value decreases due to deterioration of the processing equipment 2.

[0088] When the processing unit 11 completes the processing in step S26, or when the processing unit 11 determines that the processing equipment 2 has not started the processing (step S20: No), the processing unit 11 ends. Figure 8 The processing shown.

[0089] Figure 9 1 is a flowchart showing an example of a determination target section determination process performed by the processing unit of the degradation determination device according to the first embodiment. Figure 9 As shown, the division processing unit 41 of the processing unit 11 in the degradation determination device 1 divides the maximum numerical range by the number of divisions k to generate k divided ranges (step S30).

[0090] Next, the segmentation processing unit 41 of the processing unit 11 counts the number of measurement values ​​included in each segment range (step S31), and determines the segment range with the largest number of measurement values ​​among the k segment ranges as the determination target range (step S32), and ends. Figure 9 The processing shown.

[0091] Figure 10 1 is a flowchart showing an example of the extraction value range selection process performed by the processing unit of the degradation determination device according to the first embodiment. Figure 10 As shown, the first calculation unit 42 of the processing unit 11 calculates the average value μ and the standard deviation σ of the measurement values ​​included in the determination target range based on the plurality of measurement values ​​included in the determination target range (step S40), and calculates the central value AR of the determination target range. mid Calculation is performed (step S41).

[0092] Next, the second calculation unit 43 of the processing unit 11 calculates the first value x based on the average value μ and the standard deviation σ calculated by the first calculation unit 42. a and the second value x b Calculation is performed (step S42). The first value x a The second value x is the value obtained by subtracting the value corresponding to the standard deviation σ from the mean value μ. b This is a value obtained by adding a value corresponding to the standard deviation σ to the mean value μ.

[0093] Next, the most frequently occurring range determination unit 45 of the processing unit 11 divides the maximum numerical range into p divisions greater than the number of divisions k, generating p divided ranges (step S43). The most frequently occurring range determination unit 45 calculates the number of measured values ​​contained in each of the p divided ranges and determines the divided range with the largest number of measured values ​​as the most frequently occurring range (step S44). The number of divisions p can be a fixed value or a value proportional to the number of divisions k.

[0094] Next, the sufficiency determination unit 44 of the processing unit 11 determines the median value AR mid Is it greater than or equal to the first value x a and is less than or equal to the second value x b (Step S45). The sufficiency determination unit 44 determines that the median value AR mid Greater than or equal to the first value x a and is less than or equal to the second value x b In the case of (step S45: Yes), it is determined whether the most frequent occurrence range is greater than or equal to the first value x a and is less than or equal to the second value x b (Step S46).

[0095] The sufficiency determination unit 44 determines that the most frequent occurrence range is greater than or equal to the first value x a and is less than or equal to the second value x b In the case of (step S46: Yes), the determination target range is selected as the extraction numerical value range (step S47).

[0096] When the processing of step S47 is completed, the processing unit 11 determines that the median value AR mid Not greater than or equal to the first value x a and is less than or equal to the second value xb (step S45: No), it is determined that the most frequent occurrence range is not greater than or equal to the first value x a and is less than or equal to the second value x b In the case of (step S46: No), end Figure 10 The processing shown.

[0097] Figure 11 FIG. 1 is a flowchart showing an example of degradation determination processing performed by the processing unit of the degradation determination device according to the first embodiment. Figure 11 As shown, the degradation determination unit 31 of the processing unit 11 in the degradation determination device 1 determines whether the determination threshold is set (step S50). When the degradation determination unit 31 determines that the determination threshold is set (step S50: Yes), it performs a determination process (step S51). The determination process in step S51 is Figure 12 The processing of steps S60 to S66 will be described later.

[0098] When the degradation determination unit 31 completes the process of step S51 or determines that the determination threshold value has not been set (step S50: No), the process ends. Figure 11 The processing shown.

[0099] Figure 12 FIG. 1 is a flowchart showing an example of a determination process performed by the degradation determination unit of the degradation determination device according to the first embodiment. Figure 12 As shown, the degradation determination unit 31 determines whether the processing by the processing equipment 2 has started (step S60). In step S60, when the acquisition unit 10 acquires the operation start data from the processing equipment 2, the degradation determination unit 31 determines that the processing by the processing equipment 2 has started.

[0100] If the degradation determination unit 31 determines that the processing by the processing equipment 2 has started (step S60: Yes), it acquires the measured value from the sensor 3 via the acquisition unit 10 (step S61). Next, the degradation determination unit 31 determines whether the processing by the processing equipment 2 is complete (step S62). In step S62, if the acquisition unit 10 acquires the operation completion data from the processing equipment 2, the processing unit 11 determines that the processing by the processing equipment 2 is complete.

[0101] If the degradation determination unit 31 determines that the processing by the processing equipment 2 is not complete (step S62: No), the process proceeds to step S61 and repeatedly acquires measurement values ​​from the sensor 3 via the acquisition unit 10 until the processing by the processing equipment 2 is determined to be complete. Thus, the degradation determination unit 31 acquires time-series measurement data including multiple measurement values ​​output from the sensor 3 during one cycle of processing in the threshold determination mode. If the degradation determination unit 31 determines that the processing by the processing equipment 2 is complete (step S62: Yes), the multiple measurement values ​​included in the extraction time range are extracted from the multiple measurement values ​​included in the time-series measurement data (step S63).

[0102] Next, the degradation determination unit 31 compares the multiple measurement values ​​extracted in step S63 with the determination threshold (step S64) and determines whether the number of threshold-exceeding times is greater than or equal to a predetermined number, i.e., the set number of times (step S65). The threshold-exceeding times indicates the number of measurement values ​​that exceed the determination threshold among the multiple measurement values. If the degradation determination unit 31 determines that the threshold-exceeding times is greater than or equal to the set number of times (step S65: Yes), it outputs degradation information indicating degradation of the processing equipment 2 (step S66). For example, as a method of outputting the degradation information involved in the degradation determination unit 31, there are the display of the degradation information on the display unit 13 or the transmission of the degradation information to the terminal device 4 via the communication unit 12.

[0103] When the process of step S66 is completed, when it is determined that the processing equipment 2 has not started the processing (step S60: No), or when it is determined that the number of times the threshold value is exceeded is not greater than or equal to the set number of times (step S65: No), the degradation determination unit 31 ends the process. Figure 12 The processing shown.

[0104] Figure 13 FIG. 1 is a diagram showing an example of the hardware configuration of the degradation determination device according to the first embodiment. Figure 13 As shown, the degradation determination device 1 includes a computer having a processor 101 , a memory 102 , a communication device 103 , an interface circuit 104 , and a display device 105 .

[0105] The processor 101, memory 102, communication device 103, interface circuit 104, and display device 105 can exchange data with each other via, for example, a bus 106. The communication unit 12 is implemented by the communication device 103. The display unit 13 is implemented by the display device 105. The processor 101 reads and executes programs stored in the memory 102, thereby performing the functions of the data analysis unit 30 and the degradation determination unit 31. The processor 101 is an example of a processing circuit and includes, for example, one or more of a CPU (Central Processing Unit), a DSP (Digital Signal Processor), and a system LSI (Large Scale Integration).

[0106] The memory 102 includes one or more of RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), and EEPROM (registered trademark) (Electrically Erasable Programmable Read Only Memory). Furthermore, the memory 102 includes a recording medium on which a computer-readable program is recorded. The recording medium includes one or more of a nonvolatile or volatile semiconductor memory, a magnetic disk, a flexible memory, an optical disk, a compact disk, and a DVD (Digital Versatile Disc). Furthermore, the degradation determination device 1 may include an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0107] The degradation determination device 1 according to the first embodiment includes an acquisition unit 10, a selection unit 40, a determination unit 50, and a degradation determination unit 31. The acquisition unit 10 acquires time-series measurement data, including multiple measurement values, output from a sensor 3 that detects the state of the processing equipment 2 while the processing equipment 2 is processing a workpiece. The selection unit 40 selects, as an extracted numerical range, the range containing the largest number of measurement values ​​among the multiple ranges obtained by dividing the maximum numerical range, which is the numerical range from the minimum value to the maximum value among the multiple measurement values ​​included in the time-series measurement data acquired by the acquisition unit 10, in the threshold determination mode for determining the determination threshold. The maximum numerical range is an example of a numerical range, and the extracted numerical range is an example of an extracted range. In the threshold determination mode, the determination unit 50 determines the determination threshold based on the extracted numerical range selected by the selection unit 40 or the multiple measurement values ​​included in the extracted numerical range. The determination threshold is an example of a threshold. In the degradation determination mode for determining degradation of the processing equipment 2, the degradation determination unit 31 determines degradation of the processing equipment 2 based on the time-series measurement data acquired by the acquisition unit 10 and the determination threshold value determined by the determination unit 50. Thus, the degradation determination device 1 can save the time and effort required for pre-settings for degradation determination.

[0108] Furthermore, the selection unit 40 selects the segmented range containing the largest number of measured values ​​among the multiple segmented ranges obtained by segmenting the maximum numerical range as the determination target range. If the distribution of the multiple measured values ​​included in the determination target range satisfies the predetermined conditions, the selection unit 40 performs a selection process to select the determination target range as the extraction numerical range. If the distribution of the multiple measured values ​​included in the determination target range does not satisfy the predetermined conditions, the selection process is repeated by increasing the number k of segments of the maximum numerical range. Thus, the degradation determination device 1 can appropriately select the extraction numerical range used to determine the determination threshold.

[0109] The selection unit 40 includes a first calculation unit 42, a second calculation unit 43, and a sufficiency determination unit 44. The first calculation unit 42 calculates the average value μ and the standard deviation σ of a plurality of measurement values ​​included in the determination target range. The second calculation unit 43 calculates the first value x obtained by subtracting a value corresponding to the standard deviation σ from the average value μ. a and the second value x obtained by adding a value corresponding to the standard deviation σ to the mean value μ b The sufficiency determination unit 44 calculates the median value AR of the determination target range. mid Is it greater than or equal to the first value x a and is less than or equal to the second value x b Make a judgment, and the central value AR of the judgment object range mid Greater than or equal to the first value x a and is less than or equal to the second value x b In the case of , it is determined that the distribution of the plurality of measurement values ​​included in the determination target range satisfies the preset condition. Thus, the degradation determination device 1 can more appropriately select the extraction numerical value range for determining the determination threshold.

[0110] In addition, the selection unit 40 includes a most frequently appearing range determination unit 45, which divides the maximum numerical range into a plurality of ranges using a division number p that is larger than the division number k of the divided range, calculates the number of measurement values ​​included in each of the plurality of divided ranges, and determines the range with the largest number of measurement values ​​among the plurality of ranges as the most frequently appearing range. The sufficiency determination unit 44 determines that the most frequently appearing range determined by the most frequently appearing range determination unit 45 is greater than or equal to the first value x. a and is less than or equal to the second value x b , it is determined that the distribution of the plurality of measured values ​​included in the determination target range satisfies the predetermined condition. Thus, the degradation determination device 1 can reduce the possibility of selecting the determination target range, in which the distribution of measured values ​​includes two or more peaks, as the extraction value range, and can more appropriately select the extraction value range for determining the determination threshold.

[0111] Furthermore, the selection unit 40 extracts the time range within which the extracted numerical value range exists during one cycle of processing of the workpiece by the processing equipment 2. In the degradation determination mode, the degradation determination unit 31 determines degradation of the processing equipment 2 based on the plurality of measurement values ​​included in the time-series measurement data acquired by the acquisition unit 10, the plurality of measurement values ​​included in the extracted time range extracted by the selection unit 40, and the threshold value determined by the determination unit 50. Thus, the degradation determination device 1 can more appropriately select the measurement values ​​to be compared with the determination threshold value in the degradation determination mode, and can accurately determine degradation of the processing equipment 2.

[0112] Implementation method 2.

[0113] The degradation determination device according to Embodiment 2 differs from the degradation determination device 1 according to Embodiment 1 in that an extraction time range is selected by excluding measurement values ​​within a specific time range from a plurality of measurement values ​​included in the time-series measurement data. Components having the same functions as those in Embodiment 1 are denoted by the same reference numerals, and their description is omitted. The following description focuses on the differences from the degradation determination device 1 according to Embodiment 1.

[0114] Figure 14 FIG. 1 is a diagram showing an example of the structure of a degradation determination device according to Embodiment 2 of the present invention. Figure 14 As shown, the degradation determination device 1A according to the second embodiment differs from the degradation determination device 1 in that it includes a processing unit 11A having a data analysis unit 30A instead of the data analysis unit 30 .

[0115] Data analysis unit 30A differs from data analysis unit 30 in that it includes a selection unit 40A having a time range extraction unit 46A instead of the selection unit 40 having the time range extraction unit 46. Time range extraction unit 46A selects an extraction time range from the result of excluding measurement values ​​in a specific time range from among a plurality of measurement values ​​included in the time-series measurement data.

[0116] Figure 15 FIG. 1 is a diagram showing an example of the extraction value range and the extraction time range selected by the degradation determination device according to the second embodiment. Figure 15 In the graph, the vertical axis represents the magnitude of the measurement value, and the horizontal axis represents time.

[0117] exist Figure 15In the example, time t10 is the time when processing equipment 2 starts processing, and time t20 is the time when processing equipment 2 completes processing. Furthermore, the period from time t10 to time t11 is the period during which the measured value increases rapidly. Hereinafter, the length of time from time t10 to time t11 is referred to as period T1. Furthermore, the period that is q times period T1 is referred to as period T2. Q is 2, but other values ​​are possible.

[0118] The time range extraction unit 46A excludes the time from the start of the processing of the processing equipment 2 to the time period T2 twice the time period T1 as a specific time range. Furthermore, the time range extraction unit 46A extracts the time range in which the measured value exists in the extraction numerical range from the time range from time t12 to time t20 as the extraction time range. Figure 15 In the example shown, the time range extraction unit 46A extracts the period from time t12 to time t13 as the extraction time range. This allows the time range extraction unit 46A to accurately extract the measurement values ​​output from the sensor 3 in a state where the change is small.

[0119] Figure 16 This is a flowchart showing an example of threshold value determination processing performed by the processing unit of the degradation determination device according to the second embodiment. Figure 16 The processing of steps S70 to S74 and S77 shown is Figure 8 The processes of steps S20 to S24 and S26 are the same, and therefore their description is omitted.

[0120] like Figure 16 As shown, the time range extraction unit 46A excludes a specific time range within one cycle of the processing (step S75). The specific time range is, for example, Figure 15 The time range shown is from time t10 to time t12.

[0121] Next, the time range extraction unit 46A extracts the time ranges of the plurality of measured values ​​included in the extraction numerical range from the time range excluding the specific time range in one cycle of the processing as the extraction time range (step S76). In step S76, the time range extraction unit 46A extracts, for example, Figure 15 The time range from time t12 to time t13 shown is extracted as the extraction time range.

[0122] The hardware configuration example of the degradation determination device 1A according to the second embodiment is the same as that of the Figure 13The hardware configuration of the degradation determination device 1 shown is the same. The processor 101 reads and executes a program stored in the memory 102 , thereby enabling the functions of the data analysis unit 30A and the degradation determination unit 31 to be executed.

[0123] As described above, the selection unit 40A of the degradation determination device 1A according to the second embodiment selects an extracted numerical range from the results of excluding measurement values ​​within a specific time range from a plurality of measurement values ​​included in the time-series measurement data. This allows the degradation determination device 1A to more appropriately select measurement values ​​for comparison with the determination threshold in the degradation determination mode, thereby enabling highly accurate determination of degradation of the processing equipment 2.

[0124] Implementation method 3.

[0125] The degradation determination device according to Embodiment 3 differs from the degradation determination device 1A according to Embodiment 2 in the degradation determination method used in the degradation determination mode. Components having the same functions as those in Embodiment 2 are denoted by the same reference numerals, and their descriptions are omitted. The description will focus on the differences from the degradation determination device 1A according to Embodiment 2.

[0126] Figure 17 FIG. 1 is a diagram showing an example of the structure of a degradation determination device according to Embodiment 3 of the present invention. Figure 17 As shown, the degradation determination device 1B according to the third embodiment differs from the degradation determination device 1A in that it includes a processing unit 11B having a degradation determination unit 31B instead of the degradation determination unit 31 .

[0127] Degradation determination unit 31B includes a range selection unit 51, a comparison value determination unit 52, and a determination processing unit 53. Range selection unit 51 selects, as a comparison range, a range containing the largest number of measurement values ​​from among the multiple ranges obtained by dividing the numerical range from the minimum value to the maximum value among the multiple measurement values ​​included in the time-series measurement data acquired by acquisition unit 10 in degradation determination mode. Range selection unit 51 selects the comparison range using, for example, the same processing as that used by data analysis unit 30 or data analysis unit 30A to select an extracted numerical range.

[0128] Comparative value determination unit 52 determines the comparative value using a determination method corresponding to a selected comparative value determination mode from among a plurality of comparative value determination modes. The plurality of comparative value determination modes include, for example, a first comparative value determination mode and a second comparative value determination mode. The comparative value determination mode is set in degradation determination unit 31B, for example, by input to an input unit (not shown) or a setting button (not shown).

[0129] The comparison value determination unit 52 determines a comparison value, which is a value to be compared with the determination threshold, based on the comparison range selected by the range selection unit 51 or the plurality of measured values ​​included in the comparison range. For example, if the measured value increases due to deterioration of the processing equipment 2, the comparison value determination unit 52 determines the maximum value of the comparison range as the comparison value. Alternatively, if the measured value decreases due to deterioration of the processing equipment 2, the comparison value determination unit 52 determines the minimum value of the comparison range as the comparison value.

[0130] Furthermore, when the measured value increases as the processing equipment 2 deteriorates, the comparison value determination unit 52 determines as the comparison value a value obtained by multiplying the average value μ' of the plurality of measured values ​​included in the comparison range by m'. m' is a value greater than 1 but smaller than m. Furthermore, when the measured value decreases as the processing equipment 2 deteriorates, the comparison value determination unit 52 determines as the comparison value a value obtained by multiplying the average value μ' of the plurality of measured values ​​included in the comparison range by 1 / m'.

[0131] Furthermore, when the second comparison value determination mode is selected as the comparison value determination mode, the comparison value determination unit 52 calculates the average value μ and the standard deviation σ of the plurality of measured values ​​included in the comparison range, and calculates the comparison value by subtracting or adding a value corresponding to the calculated standard deviation σ from the calculated average value μ. Hereinafter, the average value μ and the standard deviation σ calculated by the comparison value determination unit 52 will be referred to as average value μ' and standard deviation σ' to distinguish them from the average value μ and the standard deviation σ calculated by the data analysis units 30 and 30A.

[0132] The comparison value determination unit 52 includes a calculation processing unit 61 and a comparison value calculation unit 62. When the second comparison value determination mode is selected as the comparison value determination mode, the calculation processing unit 61 calculates the average μ' and the standard deviation σ' of a plurality of measurement values ​​included in the comparison range.

[0133] The comparison value calculation unit 62 calculates the comparison value by subtracting or adding a value corresponding to the standard deviation σ' calculated by the calculation processing unit 61 from the average value μ' calculated by the calculation processing unit 61. The value corresponding to the standard deviation σ' is, for example, h' times the standard deviation σ'. h' is, for example, in the range of 0.5 to 1.5. For example, if the measured value increases due to deterioration of the processing equipment 2, the comparison value determination unit 52 determines the value obtained by adding the value corresponding to the standard deviation σ' to the average value μ' as the comparison value. Alternatively, if the measured value decreases due to deterioration of the processing equipment 2, the comparison value determination unit 52 determines the value obtained by subtracting the value corresponding to the standard deviation σ' from the average value μ' as the comparison value.

[0134] The determination processing unit 53 determines whether the processing equipment 2 has deteriorated based on the comparison result between the comparison value determined by the comparison value determination unit 52 and the determination threshold. For example, if the comparison value determined in the first comparison value determination mode is the maximum or minimum value of the comparison range, the determination processing unit 53 determines that the processing equipment 2 has deteriorated if the comparison value is w times the determination threshold. If the measured value increases due to deterioration of the processing equipment 2, w is a value greater than 1, such as 1.2. If the measured value decreases due to deterioration of the processing equipment 2, w is a value less than 1, such as 0.8.

[0135] Furthermore, the comparison value determined in the first comparison value determination mode is assumed to be a value based on the average value μ'. In this case, if the measured value increases due to deterioration of the processing equipment 2, the determination processing unit 53 determines that deterioration has occurred in the processing equipment 2 if the comparison value determined in the second comparison value determination mode is greater than the determination threshold. Furthermore, if the measured value decreases due to deterioration of the processing equipment 2, the determination processing unit 53 determines that deterioration has occurred in the processing equipment 2 if the comparison value determined in the second comparison value determination mode is less than the determination threshold.

[0136] Figure 18 This is a flowchart showing an example of comparison value determination processing performed by the processing unit of the degradation determination device according to the third embodiment. Figure 18 The processing of steps S80 to S82 shown in FIG. Figure 12 The processes in steps S60 to S62 are the same, and therefore their description is omitted.

[0137] like Figure 18 As shown, when the degradation determination unit 31B determines that the processing by the processing equipment 2 is completed (step S82: Yes), it performs the determination target section determination process (step S83). The determination target section determination process in step S83 is the same as Figure 9 The processes of steps S30 to S32 shown are the same processes.

[0138] After the degradation determination unit 31B completes the determination target section determination process in step S83, it performs a comparison range selection process (step S84). The comparison range selection process in step S84 is Figure 19 The processing of steps S90 to S97 will be described later.

[0139] Next, the degradation determination unit 31B performs a threshold determination process for determining a comparison value based on the comparison range selected by the range selection unit 51 or a plurality of measurement values ​​included in the comparison range (step S85), and ends the process. Figure 18 The decision process in step S85 is Figure 20The processing of steps S100 to S102 will be described later.

[0140] Figure 19 This is a flowchart showing an example of comparison range selection processing performed by the degradation determination unit of the degradation determination device according to the third embodiment. Figure 19 The processing of steps S90 to S97 is shown in FIG. Figure 10 In the processing of steps S40 to S47 shown in FIG. 1 , the average value μ, the standard deviation σ, the first value x a and the second value x b Replaced by mean value μ', standard deviation σ', first value x a ' and the second value x b 'After processing.

[0141] Specifically, the degradation determination unit 31B calculates the average value μ' and the standard deviation σ' of the measurement values ​​included in the determination target range based on the plurality of measurement values ​​included in the determination target range (step S90), and calculates the median value AR of the determination target range. mid Calculation is performed (step S91).

[0142] Next, the degradation determination unit 31B calculates the first value x a ' and the second value x b 'Calculation (step S92). The first value x a ' is the value obtained by subtracting the value corresponding to the standard deviation σ' from the mean value μ', and the second value x b ' is a value obtained by adding a value corresponding to the standard deviation σ' to the mean value μ'.

[0143] Next, the degradation determination unit 31B divides the maximum numerical range into p divisions greater than the division number k, generating p division ranges (step S93). Furthermore, the degradation determination unit 31B calculates the number of measured values ​​contained in each of the p division ranges and determines the division range with the largest number of measured values ​​as the most frequently occurring range (step S94).

[0144] Next, the degradation determination unit 31B determines the median value AR mid Is it greater than or equal to the first value x a ' and is less than or equal to the second value x b '(Step S95). The degradation determination unit 31B determines that the median value AR mid Greater than or equal to the first value x a ' and less than or equal to the second value x b ' (step S95: Yes), determine whether the most frequent range is greater than or equal to the first value x a ' and is less than or equal to the second value x b'(Step S96).

[0145] The degradation determination unit 31B determines that the most frequent occurrence range is greater than or equal to the first value x a ' and is less than or equal to the second value x b ' (step S96: Yes), the determination target range is selected as the comparison range (step S97). When the degradation determination unit 31B finishes the process of step S97, if it is determined that the median value AR mid Not greater than or equal to the first value x a ' and is less than or equal to the second value x b ' (step S95: No), when it is determined that the most frequent occurrence range is not greater than or equal to the first value x a ' and is less than or equal to the second value x b ' (step S96: No), end Figure 19 The processing shown.

[0146] Figure 20 : is a flowchart showing an example of a decision process performed by the degradation determination unit of the degradation determination device according to the third embodiment. Figure 20 As shown, the degradation determination unit 31B determines whether the first comparison value determination mode is selected as the comparison value determination mode (step S100 ).

[0147] If the degradation determination unit 31B determines that the first comparison value determination mode is selected (step S100: Yes), the maximum value or the minimum value of the comparison range is determined as the comparison value (step S101). If the degradation determination unit 31B determines that the first comparison value determination mode is not selected (step S100: No), the degradation determination unit 31B determines a value based on the average value μ' and the standard deviation σ' as the comparison value (step S102). If the degradation determination unit 31B completes the processing of step S101 or the processing of step S102, the degradation determination unit 31B ends. Figure 20 The processing shown.

[0148] The hardware configuration example of the degradation determination device 1B according to the third embodiment is similar to Figure 13 The hardware configuration of the degradation determination device 1 shown is the same. The processor 101 reads and executes the program stored in the memory 102 to perform the functions of the data analysis unit 30A and the degradation determination unit 31B.

[0149] As described above, the degradation determination unit 31B of the degradation determination device 1B according to the third embodiment includes a range selection unit 51, a comparison value determination unit 52, and a determination processing unit 53. The range selection unit 51 selects, as a comparison range, the range containing the largest number of measurement values ​​from among the multiple ranges obtained by dividing the numerical range from the minimum value to the maximum value among the multiple measurement values ​​included in the time-series measurement data acquired by the acquisition unit 10 in the degradation determination mode. The comparison value determination unit 52 determines a comparison value, or a value to be compared with a determination threshold, based on the comparison range selected by the range selection unit 51 or the multiple measurement values ​​included in the comparison range. The determination processing unit 53 determines degradation of the processing equipment 2 based on the comparison result between the comparison value determined by the comparison value determination unit 52 and the determination threshold. Consequently, the degradation determination device 1B can accurately determine degradation of the processing equipment 2.

[0150] The comparison value determination unit 52 includes a calculation processing unit 61 and a comparison value calculation unit 62. The calculation processing unit 61 calculates the average value μ' and the standard deviation σ' of the plurality of measurement values ​​included in the comparison range. The comparison value calculation unit 62 calculates the comparison value by subtracting or adding a value corresponding to the standard deviation σ' calculated by the calculation processing unit 61 from the average value μ' calculated by the calculation processing unit 61. This allows the degradation determination device 1B to accurately determine degradation of the processing equipment 2.

[0151] The configuration shown in the above embodiment is an example of the content of the present invention, and can be combined with other well-known technologies. Part of the configuration can also be omitted or changed without departing from the scope of the present invention.

[0152] Description of the label

[0153] 1, 1A, 1B degradation determination device, 2 processing equipment, 3 sensor, 4 terminal device, 10 acquisition unit, 11, 11A, 11B processing unit, 12 communication unit, 13 display unit, 21 time series data acquisition unit, 22 motion data acquisition unit, 30, 30A data analysis unit, 31, 31B degradation determination unit, 40, 40A selection unit, 41 segmentation processing unit, 42 first calculation unit, 43 second calculation unit, 44 sufficiency determination unit, 45 most frequently occurring range determination unit, 46, 46A time range extraction unit, 50 determination unit, 51 range selection unit, 52 comparison value determination unit, 53 determination processing unit, 61 calculation processing unit, 62 comparison value calculation unit.

Claims

1. A degradation determination device, characterized in that: have: an acquisition unit that acquires time-series measurement data including a plurality of measurement values ​​output from a sensor that detects a state of the processing equipment while the processing equipment is processing a workpiece; a selection unit that selects, as an extraction range, a range including the largest number of measurement values ​​among a plurality of ranges obtained by dividing a numerical range from a minimum value to a maximum value among the plurality of measurement values ​​included in the time-series measurement data acquired by the acquisition unit in a threshold value determination mode for determining a threshold value; a determination unit configured to determine the threshold value based on the extraction range selected by the selection unit or a plurality of measurement values ​​included in the extraction range; as well as A degradation determination unit determines degradation of the processing equipment based on the time-series measurement data acquired by the acquisition unit and the threshold value determined by the determination unit in a degradation determination mode for determining degradation of the processing equipment.

2. The degradation determination device according to claim 1, wherein: The selection unit uses the segmented range containing the largest number of measurement values ​​among the multiple segmented ranges after dividing the numerical range as the judgment object range. When the distribution of the multiple measurement values ​​contained in the judgment object range is sufficient for the preset conditions, the selection unit performs a selection process to select the judgment object range as the extraction range. When the distribution of the multiple measurement values ​​contained in the judgment object range is insufficient for the preset conditions, the number of divisions of the numerical range is increased and the selection process is repeated.

3. The degradation determination device according to claim 2, wherein: The selection unit has: a first calculation unit for calculating an average value and a standard deviation of a plurality of measurement values ​​included in the determination target range; a second calculation unit that calculates a first value obtained by adding a value corresponding to the standard deviation to the average value and a second value obtained by subtracting the value corresponding to the standard deviation from the average value; as well as A sufficiency determination unit determines whether the central value of the determination object range is greater than or equal to the first value and less than or equal to the second value, and when the central value of the determination object range is greater than or equal to the first value and less than or equal to the second value, determines that the distribution of the multiple measurement values ​​included in the determination object range satisfies the predetermined condition.

4. The degradation determination device according to claim 3, wherein: The selection unit includes a most frequently appearing range determination unit that divides the numerical range into a plurality of ranges using a division number greater than the division number of the divided range, calculates the number of measurement values ​​included in each of the plurality of divided ranges, and determines the range having the largest number of measurement values ​​among the plurality of ranges as the most frequently appearing range. The sufficiency determination unit determines that the distribution of the plurality of measurement values ​​included in the determination target range satisfies the predetermined condition when the most frequently appearing range determined by the most frequently appearing range determination unit is greater than or equal to the first value and less than or equal to the second value.

5. The degradation determination device according to any one of claims 1 to 4, characterized in that: The selection unit selects the extraction range based on a result of excluding measurement values ​​within a specific time range from among the plurality of measurement values ​​included in the time-series measurement data.

6. The degradation determination device according to any one of claims 1 to 4, characterized in that: The selection unit extracts a time range in which the extraction range exists during one cycle of processing of the workpiece by the processing equipment. In the degradation determination mode, the degradation determination unit determines degradation of the processing equipment based on a plurality of measurement values ​​included in the time range extracted by the selection unit among a plurality of measurement values ​​included in the time-series measurement data acquired by the acquisition unit and the threshold value determined by the determination unit.

7. The degradation determination device according to any one of claims 1 to 4, characterized in that: The degradation determination unit includes: a range selection unit that selects, as a comparison range, a range including the largest number of measurement values ​​among a plurality of ranges obtained by dividing a numerical range from a minimum value to a maximum value among the plurality of measurement values ​​included in the time-series measurement data acquired by the acquisition unit in the degradation determination mode; a comparison value determination unit that determines a comparison value, which is a value to be compared with the threshold value, based on the comparison range selected by the range selection unit or a plurality of measurement values ​​included in the comparison range; as well as A determination processing unit determines deterioration of the processing equipment based on a comparison result between the comparison value determined by the comparison value determination unit and the threshold value.

8. The degradation determination device according to claim 7, wherein: The comparison value determination unit includes: a calculation processing unit that calculates an average value and a standard deviation of a plurality of measurement values ​​included in the comparison range; and A comparative value calculation unit calculates the comparative value by subtracting or adding a value corresponding to the standard deviation calculated by the calculation processing unit from the average value calculated by the calculation processing unit.

9. The degradation determination device according to any one of claims 1 to 4, characterized in that: The processing equipment includes a cutting tool for cutting the workpiece and a motor for rotating the cutting tool. The measurement value of the sensor is a value of a current flowing in the motor.

10. A threshold determination device, characterized in that: have: an acquisition unit that acquires time-series measurement data including a plurality of measurement values ​​output from a sensor that detects a state of the processing equipment while the processing equipment is processing a workpiece; a selection unit that selects, as an extraction range, a range including the largest number of measurement values ​​among a plurality of ranges obtained by dividing a numerical range from a minimum value to a maximum value among the plurality of measurement values ​​included in the time-series measurement data acquired by the acquisition unit; as well as A determination unit determines a threshold value for determining deterioration of the processing equipment based on the extraction range selected by the selection unit or a plurality of measurement values ​​included in the extraction range.

11. A threshold determination method, executed by a computer, The threshold determination method is characterized by comprising: an acquiring step of acquiring time-series measurement data including a plurality of measurement values ​​outputted from a sensor detecting a state of the processing equipment while the processing equipment is processing the workpiece; a selecting step of selecting, as an extraction range, a range including the largest number of measurement values ​​among a plurality of ranges obtained by dividing a numerical range from a minimum value to a maximum value among the plurality of measurement values ​​included in the time-series measurement data acquired in the acquiring step; as well as The step of determining a threshold value for determining the deterioration of the processing equipment based on the extraction range selected in the selection step or a plurality of measurement values ​​included in the extraction range.

12. A recording medium having a threshold value determination program recorded thereon, wherein the threshold value determination program causes a computer to execute the following steps: an acquiring step of acquiring time-series measurement data including a plurality of measurement values ​​outputted from a sensor detecting a state of the processing equipment while the processing equipment is processing the workpiece; a selecting step of selecting, as an extraction range, a range including the largest number of measurement values ​​among a plurality of ranges obtained by dividing a numerical range from a minimum value to a maximum value among the plurality of measurement values ​​included in the time-series measurement data acquired in the acquiring step; as well as The step of determining a threshold value for determining the deterioration of the processing equipment based on the extraction range selected in the selection step or a plurality of measurement values ​​included in the extraction range.

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