Abnormality determination device, laser processing machine, and abnormality determination method

Abstract

The invention provides an abnormality determination device, a laser processing machine, and an abnormality determination method, which can determine processing abnormality of a workpiece with high precision. An abnormality determination device (3) for determining a machining abnormality of a workpiece (W) is provided with: a storage unit (41) for storing a state quantity detected by a sensor unit (30) in association with a movement relationship value acquired by an acquisition unit (40) when a machining unit (20) performs normal machining on the workpiece (W) while moving relative to the workpiece (W) in accordance with the movement of a movement unit (12); a calculation unit (42) that calculates a normal range of the state quantity for the movement relationship value on the basis of the information stored in the storage unit (41); and a determination unit (43) that, after the normal range is calculated, determines whether or not the state quantity detected by the sensor unit (30) is within the normal range on the basis of the calculation result of the calculation unit (42).

Description

Technical Field

[0001] The present invention relates to an abnormality determination device, a laser processing machine and an abnormality determination method. Background Art

[0002] A laser processing machine performs laser processing such as cutting by irradiating a workpiece with a laser while moving a laser head relative to the workpiece. In a laser processing machine, it is required to perform laser processing on the workpiece appropriately. Therefore, in laser processing, when a good processing quality is obtained through test processing or actual processing, a scheme is proposed in which an operator stores a laser output reference value by performing a prescribed operation and performs laser processing based on the value (for example, refer to Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Publication No. 7-61553 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In processing devices such as laser processing machines, in order to manage the processing quality, sensors that detect state quantities related to the processing of a workpiece by the processing device are sometimes provided. When determining whether there is a processing abnormality on the workpiece based on whether it deviates from a predetermined range of normal state quantities (hereinafter referred to as the "normal range"), the state quantity detected by the sensor is used. The normal range is sometimes set wider (relaxed) depending on the operating conditions of the processing device. If the normal range is expanded, there is a situation where a situation is not determined to be abnormal even in a state that should have been determined to be abnormal. Therefore, from the viewpoint of improving the accuracy of determining processing abnormalities, it is desirable to obtain a more appropriate normal range. In the above-mentioned patent document 1, the above-mentioned undesirable situation cannot be eliminated by performing laser processing only based on a reference value of the laser output.

[0008] An object of the present invention is to provide an abnormality determination device, a laser processing machine, and an abnormality determination method capable of determining abnormality in processing of a workpiece with high accuracy.

[0009] Means for solving problems

[0010] The abnormality determination device of the present invention determines the abnormality of processing of a workpiece in a processing device, wherein the processing device comprises: a moving part, which moves relative to the workpiece; and a processing part, which is arranged on the moving part and processes the workpiece while moving relative to the workpiece together with the moving part, and the abnormality determination device comprises: a sensor part, which is arranged on the moving part and moves relative to the workpiece together with the moving part while detecting a state quantity related to the processing of the workpiece by the processing device; an acquisition part, which acquires a movement relationship value related to the movement of the moving part; and a storage part, which stores the state quantity related to the movement of the moving part. When the processing unit moves relative to the workpiece and performs normal processing on the workpiece, the state quantity detected by the sensor unit and the movement relationship value obtained by the acquisition unit are stored in correspondence; the calculation unit calculates the normal range of the state quantity for each movement relationship value based on the information stored in the storage unit; and the determination unit determines whether the state quantity detected by the sensor unit is within the normal range based on the calculation result of the calculation unit after calculating the normal range when the processing unit moves relative to the workpiece and performs processing on the workpiece accompanied by the movement of the moving unit.

[0011] A laser processing machine according to an embodiment of the present invention comprises: a laser head that moves relative to a workpiece; a laser emitting unit that is provided at the laser head and emits laser light to the workpiece while moving relative to the workpiece together with the laser head to process the workpiece; and an abnormality determination device that determines abnormality in processing of the workpiece, the abnormality determination device comprising: a sensor unit that detects a state quantity of the laser processing machine while moving relative to the workpiece together with the laser head; an acquisition unit that acquires a movement relationship value related to the movement of the laser head; a storage unit that stores the state quantity detected by the sensor unit in correspondence with the movement relationship value acquired by the acquisition unit when the laser emitting unit moves relative to the workpiece and processes the workpiece normally in association with the movement of the laser head; a calculation unit that calculates a normal range of the state quantity for each of the movement relationship values ​​based on information stored in the storage unit; and a determination unit that determines whether the state quantity detected by the sensor unit is within the normal range based on a calculation result of the calculation unit when the laser head moves relative to the workpiece and processes the workpiece after calculating the normal range.

[0012] The abnormality determination method of the present invention determines the abnormality of processing of a workpiece in a processing device, wherein the processing device comprises: a moving part that moves relative to the workpiece; and a processing part that is arranged on the moving part and processes the workpiece while moving relative to the workpiece together with the moving part, and the abnormality determination method comprises: when the processing part normally processes the workpiece while moving relative to the workpiece accompanying the movement of the moving part, detecting the state quantity of the processing device by a sensor part that moves relative to the workpiece together with the moving part; acquiring a movement relationship value related to the movement of the moving part by an acquisition part; storing the state quantity detected by the sensor part and the movement relationship value acquired by the acquisition part in correspondence with each other by a storage part; calculating a normal range of the state quantity for each movement relationship value by a calculation part based on the information stored in the storage part; after calculating the normal range, when the processing part processes the workpiece while moving relative to the workpiece accompanying the movement of the moving part, determining whether the state quantity detected by the sensor part is within the normal range based on the calculation result of the calculation part.

[0013] Effects of the Invention

[0014] The abnormality determination device, the laser processing machine, and the abnormality determination method of the above-described aspect set the normal range in consideration of the movement relationship value related to the movement of the moving part, and thus can determine abnormality in processing of the workpiece with high accuracy.

[0015] Furthermore, in the abnormality determination device of the above-mentioned manner, the movement relationship value may include the movement speed of the moving part. With this configuration, since the normal range is set in consideration of the movement speed, the processing abnormality of the workpiece can be determined with high accuracy. Furthermore, in the abnormality determination device of the above-mentioned manner, the movement relationship value may include the movement direction of the moving part. With this configuration, since the normal range is set in consideration of the movement direction, the processing abnormality of the workpiece can be determined with high accuracy. Furthermore, in the abnormality determination device of the above-mentioned manner, the moving part may be a laser head of a laser processing machine, and the processing part may be a laser emitting part of the laser head that emits laser light. With this configuration, in the laser processing machine, the processing abnormality of the laser processing of the workpiece can be determined with high accuracy.

[0016] In addition, in the abnormality determination device of the above-mentioned mode, the calculation unit may calculate a table indicating a normal range for each movement relationship value based on the information stored in the storage unit, and the determination unit may determine whether the state quantity detected by the sensor unit is within the normal range based on the table. In addition, the calculation unit may derive an operation formula for calculating the normal range for each movement relationship value based on the information stored in the storage unit, and the determination unit may determine whether the state quantity detected by the sensor unit is within the normal range based on the operation formula. With this configuration, it is possible to determine the processing abnormality of the workpiece with high accuracy using the table or the operation formula. In addition, in the abnormality determination device of the above-mentioned mode, it is possible that the sensor unit detects at least one of the analysis results of the light quantity, temperature, sound, and image as the state quantity. With this configuration, it is possible to detect the processing abnormality based on at least one of the analysis results of the light quantity, temperature, sound, and image. In addition, in the laser processing machine of the above-mentioned mode, it is possible to include a head control device, and when the determination unit determines that the state quantity detected by the sensor unit is outside the normal range, the head control device stops the processing of the workpiece. With this configuration, it is possible to automatically stop the processing of the workpiece when there is a processing abnormality. Furthermore, in the laser processing machine of the above-mentioned mode, a head control device may be provided, and when the determination unit determines that the state quantity detected by the sensor unit is outside the normal range, the head control device changes the moving speed of the laser head until the state quantity detected by the sensor unit becomes within the normal range. With this configuration, when there is a processing abnormality on the workpiece, the processing abnormality can be dealt with without stopping the processing of the workpiece, and a decrease in productivity can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a diagram showing an example of a laser processing machine and an abnormality determination device according to an embodiment.

[0018] Figure 2 This is a diagram showing an example of the structure of a laser head.

[0019] Figure 3 It is a diagram showing an example of the functional section of the abnormality determination section.

[0020] Figure 4A This is a diagram showing the first example of the table.

[0021] Figure 4B This is a diagram showing the first example of the table.

[0022] Figure 5A This is a diagram showing the second example of the table.

[0023] Figure 5B This is a diagram showing the second example of the table.

[0024] Figure 5C This is a diagram showing the second example of the table.

[0025] Figure 6 This is a diagram showing a method of dividing the speed setting range.

[0026] Fig. 7A This is a diagram for explaining a method of obtaining the normal range of the state quantity from the normal range calculation table.

[0027] Figure 7B This is a diagram for explaining a method of obtaining the normal range of the state quantity from the normal range calculation table.

[0028] Figure 7C This is a diagram for explaining a method of obtaining the normal range of the state quantity from the normal range calculation table.

[0029] Figure 8 It is a flowchart showing the abnormality determination method according to the embodiment.

[0030] Fig. 9 It is a figure which shows the 1st example of the test processing shape.

[0031] Fig.10 It is a figure which shows the 2nd example of the test processing shape.

[0032] Fig.11 It is a diagram showing the problem of abnormality determination in the laser processing machine of the comparative example.

[0033] Fig.12 This is a diagram showing the relationship between the state quantity obtained in the laser processing of the comparative example, and each of the moving speed and the moving direction.

[0034] Fig.13 is a graph representing the transfer function. DETAILED DESCRIPTION

[0035] The present invention is described below by way of embodiments, but the following embodiments do not limit the invention related to the scope of the patent claim. In addition, not all combinations of features described in the embodiments are necessary for the solution of the invention. In addition, in the drawings, the same or similar parts are sometimes marked with the same symbols, and repeated descriptions are omitted. In addition, the shapes and sizes of the elements in the drawings are sometimes exaggerated to make the description clearer, and the shapes, sizes, etc. are sometimes different from the actual products.

[0036] Figure 1 1 is a diagram showing an example of a laser processing machine 1 and an abnormality determination device 3 according to an embodiment. Figure 2 Yes means Figure 1FIG. 1 is a diagram showing an example of the structure of a laser head 12 provided in a laser processing machine 1. The laser processing machine 1 of the present embodiment is a device that emits laser light L to perform laser processing such as cutting and marking on a workpiece W as a processing object. The laser processing machine 1 includes a processing device 2 and an abnormality determination device 3. The processing device 2 includes a laser oscillator 10, an illumination unit 11, a laser head 12, an imaging unit 13, a head driving unit 14, a head control device 15, and an assist gas supply unit 16.

[0037] The laser oscillator 10 generates a processing laser L1. For example, the processing laser is an infrared laser. The laser oscillator 10 is connected to a laser head 12 via an optical fiber F. The optical fiber F guides the processing laser L1 output from the laser oscillator 10 to the laser head 12. The lighting unit 11 includes a laser array 11A and a collimator 11B. The laser array 11A generates an illumination laser L2 having a wavelength different from that of the processing laser L1. The collimator 11B is disposed at a position where the illumination laser L2 is incident from the laser array 11A, and converts the illumination laser L2 incident from the laser array 11A into parallel light.

[0038] The laser head 12 irradiates the laser L (processing laser L1 and illumination laser L2) from the nozzle 20 toward the workpiece W. The laser head 12 is provided so as to be relatively movable in the X direction, the Y direction, and the Z direction relative to the workpiece W. The laser head 12 performs the cutting process by irradiating the processing laser L1 along the cutting line formed on the workpiece W while moving relatively relative to the workpiece W. In addition, the laser head 12 is an example of a "moving unit".

[0039] like Figure 2 As shown, the laser head 12 includes a nozzle 20, a collimator 21, a beam splitter 22, a focusing lens 23, a half mirror 24, a wavelength selection filter 25, and an imaging lens 26. The nozzle 20 is installed below the laser head 12 (-Z side). The nozzle 20 faces downward. The nozzle 20 has an emission hole 20A.

[0040] The processing laser L1 and the illumination laser L2 are irradiated downward from the emission hole 20A. The nozzle 20 is connected to the auxiliary gas supply unit 16 via a gas supply pipe or the like. The nozzle 20 supplies the auxiliary gas from the auxiliary gas supply unit 16 to the workpiece W toward the area irradiated with the processing laser L1. In addition, the nozzle 20 is an example of a processing unit, which is equivalent to a laser emitting unit. In addition, in the method in which the sensor 30 detects the amount of light, temperature, sound, etc. (a method of detecting state quantities other than the analysis results of the image), it is not necessary to set the configuration of the lighting unit 11, the shooting unit 13, the beam splitter 22, the half mirror 24, the wavelength selection filter 25, the imaging lens 26, etc.

[0041] The collimator 21 is set so that the focus of the incident side of the processing laser L1 coincides with the position of the end of the optical fiber F, and converts the processing laser L1 output from the laser oscillator 10 into parallel light. The beam splitter 22 is set at the position where the processing laser L1 after passing through the collimator 21 is incident. The focusing lens 23 that transmits the processing laser L1 and reflects the illumination laser L2 is set at the position where the processing laser L1 from the beam splitter 22 is incident, and focuses the incident processing laser L1. The focusing lens 23 can be moved along the optical axis by an optical system driving unit (not shown). The focus on the workpiece W side is adjusted by the optical system driving unit.

[0042] The half mirror 24 is disposed at a position where the illumination laser light L2 after passing through the collimator 11B is incident, and reflects a part of the illumination laser light L2 and allows a part of the illumination laser light L2 to pass through. The illumination laser light L2 reflected by the half mirror 24 is reflected by the beam splitter 22. The focusing lens 23 focuses the illumination laser light L2 reflected from the beam splitter 22. The region of the workpiece W to be irradiated with the illumination laser light L2 is set to include the region to which the workpiece W is irradiated with the processing laser light L1.

[0043] The return light from the workpiece W is incident on the beam splitter 22 through the condenser lens 23. The return light includes the light of the illumination laser L2 reflected and scattered by the workpiece W, and the light of the processing laser L1 reflected by the workpiece W. The light from the illumination laser L2 is reflected by the beam splitter 22 and incident on the half mirror 24. Similarly, the light from the processing laser L1 is reflected by the beam splitter 22 and incident on the half mirror 24. In the case where the molten metal after the workpiece W is melted is welded on the cut surface of the workpiece W, etc., the return light includes the light in the infrared to near-infrared band radiated from the molten metal. The light caused by the molten metal is reflected by the beam splitter 22 and incident on the half mirror 24.

[0044] The wavelength selection filter 25 is, for example, a dichroic mirror, a notch filter, etc. The return light incident on the half mirror 24 is incident on the wavelength selection filter 25 through the half mirror 24. The light from the illumination laser L2 is reflected by the wavelength selection filter 25 and is incident on the imaging lens 26. On the other hand, the light from the processing laser L1 passes through the wavelength selection filter 25. The imaging lens 26 focuses the light reflected by the wavelength selection filter 25 on the imaging unit 13.

[0045] The imaging unit 13 is provided in the laser head 12. The imaging unit 13 is a device for imaging the area irradiated with the processing laser L1. The imaging unit 13 includes an imaging element 13A. The imaging element 13A is an image sensor that detects the return light of the illumination laser L2 after being reflected and scattered by the workpiece W, and generates image data. The imaging unit 13 sends the image data generated by the imaging element 13A to the head control device 15.

[0046] The head driving unit 14 is controlled by the head control device 15 to move the laser head 12 in each of the X direction, the Y direction, and the Z direction. The head driving unit 14 includes, for example, a frame that can move in the X direction, a slider that can move relative to the frame in the Y direction, and a lifting unit that can move relative to the slider in the Z direction. In addition, the head driving unit 14 is not limited to the above-mentioned structure, and can also be implemented by other structures such as a robot arm.

[0047] The head control device 15 controls the movement of the laser head 12 by controlling the head drive unit 14. For example, the head control device 15 obtains the position information of the laser head 12 at a predetermined period, and controls the head drive unit 14 based on the obtained position information, thereby controlling the movement of the laser head 12. In addition, the head control device 15 obtains a value related to the movement of the laser head 12, that is, a movement relationship value, based on the position information of the laser head 12. The movement relationship value is, for example, both or either of the moving speed and the moving direction of the laser head 12. In addition, the moving direction is the processing direction of the laser processing. The head control device 15 controls the head drive unit 14 so that the obtained movement relationship value becomes a preset setting value. In addition, the head control device 15 outputs the obtained movement relationship value to the abnormality determination device 3.

[0048] The auxiliary gas supply unit 16 is connected to the laser head 12. The auxiliary gas supply unit 16 is a device for supplying auxiliary gas into the nozzle 20. The auxiliary gas is used to remove the molten material in the laser processing. As the supply source of the auxiliary gas, for example, a gas cylinder, a supply line of a factory, etc. are used. As the auxiliary gas, for example, nitrogen, air, a gas mixed with nitrogen and oxygen, etc. are used.

[0049] The abnormality determination device 3 may also include an image processing unit (not shown) that generates data related to the processing state based on the image data generated by the imaging element 13A. For example, as data related to the processing state, the image processing unit may generate data indicating the width of the cut, may produce numerical information indicating the combustion state such as the behavior of the molten metal in the workpiece W, or may include both. The data related to the processing state may also be an example of the analysis result of the above-mentioned image. The abnormality determination device 3 determines the processing abnormality of the workpiece W in the processing device 2. The abnormality determination device 3 includes a sensor 30 and an abnormality determination unit 31.

[0050] The sensor 30 is provided at the laser head 12. The sensor 30 is, for example, integrally provided at the laser head 12, and is configured to move in the same manner as the laser head 12 moves. The sensor 30 may also be provided inside the laser head 12. The sensor 30 moves relative to the workpiece W together with the laser head 12 as the laser head 12 moves, and detects a state quantity X related to the processing of the workpiece W by the processing device 2. The state quantity X refers to one or more data used by the abnormality determination unit 31 to determine whether the processing device 2 is normal or abnormal, and is a value that directly or indirectly indicates the state of the processing device 2. Here, the sensor 30 is an example of the "sensor unit" of the present invention. For example, the "sensor unit" of the present invention detects at least one of the analysis results of light quantity, temperature, sound, and image as the state quantity X.

[0051] As an example, the "sensor unit" of the present invention may include any one of the following sensors or two or more sensors. That is, the state quantity X may be a sensor value detected by one or more of the following sensors.

[0052] (a) A temperature sensor that detects heat generated by the condensing lens 23 for condensing and diffusing laser light.

[0053] (b) A light amount sensor that detects the light amount of the reflected light of the processing laser light L1.

[0054] (c) A sound sensor that detects sound around the laser head 12.

[0055] (d) An image sensor that monitors the size of the cut groove and the behavior of the molten metal based on an image near the processing point.

[0056] In addition, when the sensor unit is the sensor exemplified in (a), (b) or (c), the sensor unit is equivalent to the sensor 30. In this case, the lighting unit 11, the imaging unit 13 and the image processing unit are not necessary components for implementing the present invention. On the other hand, when the sensor unit is the sensor of (d), the sensor unit is equivalent to the lighting unit 11, the imaging unit 13 and the image processing unit. In this case, Figure 1 The sensor 30 illustrated in the figure is not a necessary structure for implementing the present invention. In the case where the above-mentioned sensor unit is equivalent to the lighting unit 11, the shooting unit 13 and the above-mentioned image processing unit, the abnormality determination device 3, for example, includes the lighting unit 11, the shooting unit 13 and the above-mentioned image processing unit as the sensor unit. Here, the above-mentioned image processing unit may be included in the abnormality determination unit 31, or may be a device other than the abnormality determination unit 31. The device other than the abnormality determination unit 31 may also be, for example, the shooting unit 13. In the example shown below, for the sake of convenience, the case where the above-mentioned sensor unit is the sensor 30 is taken as an example for explanation.

[0057] The abnormality determination unit 31 is, for example, an information processing device such as a computer. The abnormality determination unit 31 is connected to the head control device 15 and can send and receive information to and from the head control device 15. The abnormality determination unit 31 is connected to the sensor 30. The abnormality determination unit 31 determines the machining abnormality of the workpiece W in the machining device 2 based on the state quantity X detected by the sensor 30.

[0058] Figure 3 2 is a diagram showing an example of a functional unit of the abnormality determination unit 31. Figure 3 As shown, the abnormality determination unit 31 includes an acquisition unit 40, a storage unit 41, a calculation unit 42, a determination unit 43, and an output unit 44. These components are implemented by executing a program (software) through a hardware processor such as a CPU (Central Processing Unit). In addition, some or all of these components can be implemented by hardware (including circuitry) such as LSI (Large Scale Integrated circuit) or ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), GPU (Graphics Processing Unit), etc., or can be implemented by the collaboration of software and hardware.

[0059] The program may be stored in advance in a storage device (a storage device having a non-temporary storage medium) such as an HDD (Hard Disk Drive) or a flash memory, or may be stored in a removable storage medium (a non-temporary storage medium) such as a DVD or CD-ROM, and installed in the storage device by attaching the storage medium to a drive device. The storage device may be composed of, for example, an HDD, a flash memory, an EEPROM (Electrically Erasable Programmable Read Only Memory), a ROM (Read Only Memory), or a RAM (Random Access Memory).

[0060] The acquisition unit 40 acquires the movement relationship value related to the movement of the laser head 12. For example, the acquisition unit 40 acquires the movement relationship value from the head control device 15. The acquisition unit 40 may include a communication interface for communicating with the head control device 15, for example.

[0061] When normal laser processing (hereinafter referred to as "test processing") is performed on the workpiece W by irradiating the laser from the nozzle while moving the laser head 12, the storage unit 41 stores the state quantity X detected by the sensor 30 and the movement relationship value obtained by the acquisition unit 40 in correspondence. In other words, the storage unit 41 stores the state quantity X detected by the sensor 30 and the movement relationship value obtained by the acquisition unit 40 in correspondence at regular intervals during the test processing. In addition, when the "sensor unit" of the present invention is the sensor of (d) above, the abnormality determination unit 31 may also include the above-mentioned image processing unit as a functional unit. In this case, the storage unit 41 obtains the analysis result of the image from the image processing unit as the state quantity X.

[0062] Test processing is laser processing in a state where no processing abnormality occurs in the test workpiece W (hereinafter referred to as the "test workpiece"). For example, the processing conditions of the test processing are adjusted in advance so that laser processing can be performed without causing a decrease in the quality of the processed product due to excessive burning or poor cutting. In this test processing, the operator determines whether to perform normal laser processing on the workpiece W based on the actual processing appearance and processing properties of the workpiece. In this way, in the storage unit 41, test data of information corresponding to the state quantity X and the movement relationship value during normal laser processing is stored in the storage unit 41. In addition, in order to distinguish the state quantity X detected by the sensor 30 from others in the test processing, it is sometimes referred to as "state quantity X1".

[0063] The calculation unit 42 calculates the normal range of the state quantity X (hereinafter referred to as the "normal range") for each movement relationship value based on the test data of the information corresponding to the state quantity X and the movement relationship value during normal laser processing stored in the storage unit. For example, the calculation unit 42 creates a table 100 that directly or indirectly determines the normal range of the state quantity X for each movement relationship value based on the test data stored in the storage unit 41. In addition, the calculation unit 42 can create the table 100 for each workpiece W (material and plate thickness of the workpiece W, etc.), can create the table 100 for each processing condition for processing the workpiece W, or can use both. The processing conditions are, for example, the output of the processing laser L1, the focus position of the processing laser L1 relative to the workpiece, and the pressure of the assist gas.

[0064] For example, table 100 is a table that directly determines the normal range of the state quantity X in a matrix for each moving speed and moving direction (hereinafter referred to as a "normal range table"), and may also be composed of one or more tables. FIG. 4 is a diagram showing a first example of a normal range table of the present embodiment. In FIG. 4, as a normal range, the maximum value and the minimum value of the state quantity X are expressed in absolute values. The normal range table shown in FIG. 4 has a minimum value table ( Figure 4A ) and the maximum value table ( Figure 4B The minimum value table is a table that determines the minimum value of the normal range of the state quantity X in a matrix for each setting range of the moving speed (hereinafter referred to as the "speed setting range") and the setting range of the moving direction (hereinafter referred to as the "direction setting range"). The maximum value table is a table that determines the maximum value of the normal range of the state quantity X in a matrix for each speed setting range and direction setting range.

[0065] FIG5 is a diagram showing a second example of table 100. Table 100 may also be a table that indirectly determines the normal range of the state quantity X in a matrix form for each moving speed and moving direction. For example, as shown in FIG5 , table 100 is a table that determines the information (e.g., statistical information) used to calculate the normal range of the state quantity X in a matrix form for each moving speed and moving direction (hereinafter referred to as a “normal range calculation table”), and may also be composed of one or more tables. In the normal range calculation table shown in FIG5 , an average value, a standard deviation, and a sampling number are used as statistical information. More specifically, the normal range calculation table shown in FIG5 has an average value table ( Figure 5A ), Standard Deviation Table( Figure 5B ) and the sampling number table ( Figure 5C ).

[0066] The average value table is a table that determines the average value of the state quantity X1 in a matrix for each speed setting range and direction setting range. The standard deviation table is a table that determines the standard deviation of the state quantity X1 in a matrix for each speed setting range and direction setting range. The sampling number table is a table that determines the sampling number of the state quantity X1 in a matrix for each speed setting range and direction setting range. The sampling number of the state quantity X1 is the number of state quantities X1 used to prepare the average value table or the standard deviation table. In addition, the statistical information used to calculate the normal range is not limited to the average value, standard deviation and sampling number, and may also include other statistical information such as kurtosis and skewness.

[0067] Figure 6 : is a diagram showing a method of dividing the speed setting range. The widths of the speed setting ranges may be all the same width, or may not be all the same width. For example, the widths of the speed setting ranges may be set exponentially so that the widths of the speed setting ranges become wider as the speed increases. That is, as a method of dividing the normal range table into a matrix for each moving speed and moving direction, the following method may be used: Figure 6 As shown in (A) of FIG. 1 , the linear division can be performed in equal parts. Figure 6 As shown in (B) of FIG. 1 , the speed setting range is divided into an exponential function so that a wider range is obtained as the speed increases.

[0068] The method of dividing the speed setting range linearly and equally is simple in structure and is useful in situations where the speed is stable at low speeds or the like and where you want to reliably associate the normal range with the moving speed. The method of dividing the speed setting range exponentially is that even when the moving speed varies greatly in a high-speed area, the parameters referenced in the table are unlikely to change, so the abnormality judgment standard can be stabilized. That is, the method of dividing the speed setting range exponentially is useful when the moving speed varies greatly in a high-speed area. Figure 6 In the example (B), for the speed setting range of 21 to 33 m / min, refer to the same table parameters. Figure 6 In (A), for the speed setting range of 21 to 33 m / min, it is necessary to refer to three table parameters.

[0069] When the laser head 12 is moved to perform actual laser processing (hereinafter referred to as "actual processing") on a workpiece W that is not for testing, the determination unit 43 determines whether the state quantity X detected by the sensor 30 is within the normal range based on the table 100 as an example of the calculation result of the calculation unit 42. After the table 100 is calculated, the actual processing is performed.

[0070] For example, during actual processing, the determination unit 43 obtains the state quantity X detected by the sensor 30 and the movement relationship value of the laser head 12 at regular intervals. The state quantity X in actual processing is sometimes referred to as "state quantity X2". The determination unit 43 obtains the normal range corresponding to the movement relationship value in actual processing from the normal range table. Then, the determination unit 43 determines whether the state quantity X2 is within the read normal range at regular intervals. When the state quantity X2 is outside the normal range, the determination unit 43 determines that there is a processing abnormality. For example, when the state quantity X2 is outside the normal range even once, the determination unit 43 determines that there is a processing abnormality.

[0071] However, the present invention is not limited to this mode, and the determination unit 43 may determine that there is a machining abnormality when the number of times the state quantity X2 becomes outside the normal range exceeds a predetermined number (an integer greater than 1) within the most recent predetermined period. In addition, the number of times the abnormality is determined to exist may be the number of times the state quantity X continuously becomes outside the normal range within the most recent predetermined period. In addition, the above-mentioned predetermined number of times may also be changed according to the workpiece W as the machining object and the machining conditions.

[0072] In addition, when the normal range calculation table is used in the abnormality determination, the calculation unit 42 obtains the state quantity X2 detected by the sensor 30 and the movement relationship value in the actual processing at regular intervals during the actual processing. Then, the calculation unit 42 obtains the average value and standard deviation corresponding to the movement relationship value in the actual processing, and creates the normal range based on the obtained average value and standard deviation.

[0073] FIG. 7 is a diagram for explaining a method for obtaining a normal range of a state quantity X based on a normal range calculation table. Fig. 7A As shown, the calculation unit 42 may also calculate the range between the upper limit value shown in formula (1) and the lower limit value shown in formula (2) as the normal range based on the average value and standard deviation obtained from the normal range calculation table. However, this is not limited to this method. The calculation unit 42 may calculate the range below the upper limit value shown in formula (1) as the normal range ( Figure 7B ), the range above the lower limit value shown in formula (2) can also be calculated as the normal range ( Figure 7C ). The determination unit 43 determines whether the state quantity X2 is within the normal range by the same method as the above-mentioned abnormality determination.

[0074] Upper limit = average value + α1 × standard deviation (1)

[0075] Lower limit = average value - α2 × standard deviation (2)

[0076] The gain α1 and the gain α2 may be the same value or different values. In the example shown in FIG7 , the case where both α1 and α2 are "3" is shown as an example. In addition, α1 and α2 may be set based on the kurtosis and skewness, respectively.

[0077] Here, when the number of samples corresponding to the movement relationship value in the actual processing obtained in a certain cycle is extremely small, the judgment unit 43 may not implement the abnormal judgment of the state quantity X2 in the cycle, or may implement the gain adjustment processing such as increasing the values ​​of the gain α1 and the gain α2 from "3" to "4" in the abnormal judgment in the cycle.

[0078] The output unit 44 outputs the determination result of the determination unit 43. For example, the output unit 44 may output the determination result only when the determination unit 43 determines that there is a processing abnormality. For example, the output unit 44 may output the determination result of the determination unit 43 to a display device (not shown) to display the determination result of the determination unit 43 on the display device. However, it is not limited to this method, and the output unit 44 may output the determination result of the determination unit 43 to a communication terminal used by a user via a wired or wireless communication network. In addition, the determination result of the determination unit 43 may also be used for feedback control of processing conditions (reducing the moving speed, etc.). For example, when the determination unit 43 determines that there is a processing abnormality, the output unit 44 may output a signal indicating the determination result to the head control device 15. When the head control device 15 obtains a signal indicating the determination result of the determination unit 43, it may also implement feedback control to change the moving speed until the moving speed becomes within a normal range.

[0079] Hereinafter, the flow of the abnormality determination method according to the present embodiment will be described. Figure 8 1 is a flowchart of the abnormality determination method of the present embodiment. The laser processing machine 1 first starts test processing (step S101). During the test processing, the abnormality determination device 3 stores the state quantity X detected by the sensor 30 and the movement relationship value of the laser head 12 in correspondence (step S102). Based on the information stored in the storage unit, the abnormality determination device 3 calculates the normal range of the state quantity X for each movement relationship value (step S103).

[0080] Here, in the test processing, the laser processing machine 1 laser processes the test workpiece into a preset shape (hereinafter referred to as a "test processing shape"). The test processing shape is a shape that can ensure a sufficient number of samplings for the moving speed and moving direction that frequently appear in the shape processed in actual processing. Fig. 9 This is the first example of testing the processing shape. Fig. 9 As shown, the laser processing machine 1 moves the laser head while laser processing a plurality of regular dodecagons in a nested shape as a test processing shape. The laser processing machine 1 can also change the maximum speed of the laser head 12 with each regular dodecagon. The first shape can generate the state quantity X in each moving direction every 30° with an equal number of samplings.

[0081] Fig.10 This is the second example of testing the processing shape. Fig.10As shown, the laser processing machine 1 moves the laser head while laser processing a plurality of squares in a nested shape as a test processing shape. For example, the laser processing machine 1 changes the maximum speed of the laser head 12 for each square to process the corners of the square into a circle. In the case where the test processing shape is limited to a rectangle, the second shape can store more data of the state quantity X1 when the moving directions are 0°, 90°, 180°, and 270°. In addition, in the second shape, since the corners of the square are processed into a circle, the state quantity X1 in the moving directions other than 0°, 90°, 180°, and 270° can be stored.

[0082] The processing from step S101 to step S103 is the processing implemented before the actual processing. After these processing are completed, the actual processing is performed (step S104). In addition, after executing the processing from step S101 to step S103 once, as long as the processing object (material and shape of the workpiece) does not change, the processing from step S101 to step S103 can be stopped, and the actual processing described below can be performed for a certain period (more than several months depending on the situation). When performing the actual processing, the abnormality determination device 3 performs an abnormality determination (step S105) on whether there is a processing abnormality. For example, the abnormality determination device 3 obtains the movement relationship value and the state quantity X2 during the actual processing. Then, the abnormality determination device 3 selects the normal range corresponding to the obtained movement relationship value from the normal range of each movement relationship value calculated in step S103. Then, the abnormality determination device 3 determines whether the state quantity X2 converges within the selected normal range. When the state quantity X2 converges within the normal range, it is determined that there is no processing abnormality. The abnormality determination device 3 determines that there is a machining abnormality when, for example, the state quantity X2 is outside the normal range once or more than once.

[0083] When the abnormality determination device 3 determines in step S105 that no machining abnormality has occurred, it determines whether the actual machining is completed (step S106). When the actual machining is not completed, the abnormality determination device 3 moves to step S105 again.

[0084] When the determination unit 43 determines that there is a processing abnormality in step S105, the output unit 44 outputs the determination result to, for example, a display device (step S107). In this way, the output unit 44 notifies the user of the processing abnormality. In addition, when the output unit 44 determines that there is no processing abnormality, it may or may not output the determination result. In addition, when the abnormality determination device 3 determines that there is a processing abnormality in step S105, it may communicate with the head control device 15 to stop the actual processing. For example, when the abnormality determination device 3 determines that there is a processing abnormality in step S105, it sends a signal indicating this, i.e., a processing abnormality signal, to the head control device 15. When the head control device 15 receives the processing abnormality signal, it may also stop the processing of the workpiece. However, it is not limited to this. When the head control device 15 receives the processing abnormality signal, it may not stop the processing of the workpiece, but perform feedback control such as reducing the moving speed in the actual processing. As an example, when the head control device 15 receives the processing abnormality signal, it may also change the moving speed of the laser head 12 until the state quantity X detected by the sensor unit such as the sensor 30 becomes within the normal range. In other words, when the determination unit 43 determines that the state quantity X detected by the sensor unit is outside the normal range, the head control device 15 may change the moving speed of the laser head 12 until the state quantity X detected by the sensor unit becomes within the normal range. With this configuration, when there is a processing abnormality on the workpiece W, the laser processing machine 1 can respond to the processing abnormality without stopping the processing of the workpiece W.

[0085] Hereinafter, the effects of this embodiment will be described. Fig.11 It is a diagram showing the problem of abnormality determination in the laser processing machine of the comparative example. Fig.12 This is a diagram showing the relationship between the state quantity obtained in normal laser processing and each of the moving speed and moving direction. Fig.11 (A) shows the state quantity obtained in normal laser processing. Fig.11 (B) and Fig.11 (C) shows the moving speed and moving direction of the laser head at this time.

[0086] The inventor of the present application discovered that Fig.11 as well as Fig.12As shown in FIG. 1 , the state quantity X in a normal state may have different values ​​depending on the moving relationship values ​​such as the moving speed and moving direction of the laser head 12. The main reasons for this are the different heat transfer methods, the influence of the heat already accumulated in the workpiece, the shape and eccentricity of the laser beam, the directivity of the sensor 30 itself, etc. In the previous abnormality judgment, the difference in the state quantity X caused by the moving relationship values ​​such as the moving speed and moving direction of the laser head 12 was not considered. In addition, in order to avoid "false judgment" that the processing is abnormal when the processing is normal, sometimes the value of the state quantity X is not considered. Fig.11 The large range 200 shown in (A) is set as the normal range.

[0087] Here, range 200 is a fixed range that is independent of the movement relationship value. Therefore, a range 210 that is a part of range 200 sometimes deviates from the range of the state quantity X obtained in normal laser processing, and it is considered that processing abnormality may occur even when the state quantity X is within range 210. In such a case, if the normal range is set to range 200 as described above, it may cause a situation where the occurrence of processing abnormality cannot be detected even if there is a processing abnormality. The abnormality determination device 3 of this embodiment sets the range that takes the movement relationship value into consideration, that is, the range 300 that changes according to the movement relationship value, as the normal range. With such a configuration, when the state quantity X within range 210 is detected, it can be determined as a processing abnormality, and the processing abnormality of the workpiece W can be determined with high accuracy.

[0088] In the above-described embodiment, the state quantity X detected by the sensor unit such as the sensor 30 is directly transmitted to the abnormality determination device 3. However, the present invention is not limited to this mode, and the state quantity X detected by the sensor unit may be transmitted to the head control device 15. In this case, the state quantity X is transmitted from the head control device 15 to the abnormality determination device 3.

[0089] In the above-mentioned embodiment, the abnormality determination device 3 obtains the movement relationship value from the head control device 15. However, the present invention is not limited to this mode, and the abnormality determination device 3 (for example, the acquisition unit 40) may obtain the position information of the laser head 12 from the head control device 15 or the laser head 12, and obtain the movement relationship value based on the obtained position information of the laser head 12. In addition, the abnormality determination device 3 may also use both the movement relationship value obtained from the head control device 15 and the movement relationship value obtained based on the position information of the laser head 12. In this case, the acquisition unit 40 of the abnormality determination device 3 may use either the movement relationship value obtained from the head control device 15 or the movement relationship value obtained by itself, or may newly obtain the average value of the values ​​of both as the movement relationship value.

[0090] In the above embodiment, the normal range of the state quantity X of each movement relationship value is set as the table 100. However, the present invention is not limited to this method. For example, the calculation unit 42 may calculate the normal range of the state quantity X of each movement relationship value as an operation expression based on the information stored in the storage unit 41. When the normal range is expressed as an operation expression, for example, the following equations (3) to (5) may be considered.

[0091] Xmin≤X≤Xmax……(3)

[0092] Xmax(v,θ)=a 0 V 2 +a 1 V+a 2 +b 0 sin(b 1 θ+b 2 )……(4)

[0093] Xmin(v,θ)=c 0 V 2 +c 1 V+c 2 +d 0 sin(d 1 θ+d 2 )……(5)

[0094] Xmin is the maximum value of the normal value of the state quantity X, and Xmax is the minimum value of the normal value of the state quantity X. v represents the moving speed of the laser head 12, and θ represents the moving direction of the laser head 12. n 、b n 、c n d n (n is 1 to 3) is a constant and may be set for each type of processing object, processing condition, or state quantity X.

[0095] In the above-mentioned embodiment, an example is described in which the calculation unit 42 calculates the range between the upper limit value shown in formula (1) and the lower limit value shown in formula (2) as a normal range based on the average value and standard deviation obtained from the normal range calculation table, but it is not limited to this method. For example, the calculation unit 42 may also calculate the range between the upper limit value shown in formula (6) and the lower limit value shown in formula (7) as a normal range based on the average value obtained from the normal range calculation table. However, it is not limited to this method, and the calculation unit 42 may calculate the range below the upper limit value shown in formula (6) as the normal range, or may calculate the range above the lower limit value shown in formula (7) as the normal range. In addition, the fixed value shown below is pre-set, and may also be set based on the information stored in the storage unit 41.

[0096] Upper limit value = average value + fixed value... (6)

[0097] Lower limit value = average value - fixed value... (7)

[0098] In the above-mentioned embodiment, the determination unit 43 may also consider the rate of change of the state quantity X in the abnormality determination, and determine that it is a processing abnormality when the rate of change of the state quantity X2 deviates from the reference value. For example, assuming that the state quantity X2 is obtained at a certain period T, the state quantity X2 at time t is represented by X(t). Here, the rate of change of the state quantity X2 is both or either the rate of change ΔX(t) of the state quantity X2 per unit time and the rate of change Δ′X(t) of the state quantity X per moving distance. The rate of change ΔX(t) is represented by the following formula (8). The rate of change Δ′X(t) is represented by the following formula (9).

[0099] ΔX(t)=(X(t)-ΔX(tT)) / T……(8)

[0100] ΔX′(t)=(X(t)-ΔX(tT)) / (v(t)·T)……(9)

[0101] The determination unit 43 may calculate the change rate ΔX(t) during actual machining, and determine that machining is abnormal when the change rate ΔX(t) exceeds the upper limit. The determination unit 43 may determine that machining is abnormal when the change rate ΔX(t) is lower than the lower limit. The determination unit 43 may determine that machining is abnormal when the change rate ΔX(t) deviates from the range between the upper limit and the lower limit.

[0102] Furthermore, the determination unit 43 may calculate the change rate Δ′X(t) during actual machining, and determine that machining is abnormal when the change rate Δ′X(t) exceeds the upper limit value. The determination unit 43 may determine that machining is abnormal when the change rate Δ′X(t) is lower than the lower limit value. The determination unit 43 may determine that machining is abnormal when the change rate Δ′X(t) deviates from the range between the upper limit value and the lower limit value.

[0103] Here, when the rate of change of the state quantity X is used for abnormality determination, the upper limit value and the lower limit value of the rate of change of the state quantity X may be calculated based on the information stored in the storage unit 41. In other words, the calculation unit 42 may calculate the upper limit value and the lower limit value of the rate of change of the state quantity X for each movement relationship value based on the information stored in the storage unit 41 as the normal range of the state quantity X. In this case, the upper limit value and the lower limit value of the rate of change of the state quantity X may be set by a table or by an arithmetic expression. In addition, the upper limit value and the lower limit value of the rate of change may be changed according to the workpiece W as the processing object and the processing conditions.

[0104] In the abnormality determination of the above-described embodiment, a transfer function G may be provided that can take into account the continuity of the state quantity deviating from the normal range. Fig.13 : is a diagram showing the transfer function G of the present embodiment. The determination unit 43 may also process the determination of normality or abnormality as a continuous quantity from 0 to 1, for example, and use the transfer function G of a first delay or the like to determine whether there is a processing abnormality. For example, the determination unit 43 sets normality to "0" and abnormality to "1", and inputs a value indicating whether the state quantity X2 of each certain period is normal or abnormal into the transfer function G of a first delay or the like. Then, the determination unit 43 determines that there is a processing abnormality only when the value output from the transfer function G exceeds the threshold value S. With this configuration, it is possible to detect only abnormalities that last for a long time. In addition, the threshold value S may also be changeable according to the workpiece W to be processed and the processing conditions.

[0105] In the above-mentioned embodiment, when the state quantity X includes multiple sensor values, the calculation unit 42 may also calculate the normal range of the state quantity X of each moving relationship value for each sensor value (for example, Table 100, calculation formula, etc.). In this case, the determination unit 43 may also perform abnormality determination separately for each sensor value. The determination unit 43 may also determine that it is a processing abnormality when even one of the determination results of each sensor value deviates from the normal range, that is, the abnormality of the sensor value is detected. However, it is not limited to this method. For example, the number of items that allow the upper limit of the abnormality of the sensor value may be set, and when the abnormality of the sensor value exceeding the number of the item is detected, it is determined as a processing abnormality. In addition, the determination unit 43 may also set a weight for the abnormal determination of each sensor value to generate a total score. Then, the determination unit 43 may also determine that it is a processing abnormality when the score exceeds a specified value. In addition, the specified value may also be able to change according to the workpiece W as the processing object and the processing conditions.

[0106] In the above embodiment, when the state quantity X includes a plurality of sensor values, the determination unit 43 may also correlate the behaviors of the plurality of sensor values, generate a state quantity X3 as a new determination index, and perform abnormal determination on the generated state quantity X3. In this case, the calculation unit 42 calculates the normal range of the state quantity X3 for each movement relationship value by the above method such as the table 100 and the calculation formulas exemplified in formulas (3) to (5).

[0107] In the above embodiment, the abnormality determination device 3 is applied to the laser processing machine 1. However, the device to which the abnormality determination device 3 is applied is not limited to the laser processing machine 1, and may be applied to a plotter that uses NC (Numerical Control) to perform plotting, a cutting machine that performs cutting processing, or a machining center, etc.

[0108] <Notes>

[0109] The above-mentioned embodiment discloses at least the following configurations.

[0110] (Composition 1)

[0111] An abnormality determination device is provided for determining a machining abnormality of a workpiece in a machining device, wherein the machining device comprises: a moving portion that moves relative to the workpiece; and a machining portion that is disposed on the moving portion and processes the workpiece while moving relative to the workpiece together with the moving portion.

[0112] The abnormality determination device comprises:

[0113] A sensor unit for detecting a state quantity related to processing of the workpiece by the processing device;

[0114] an acquiring unit, which acquires a movement relationship value related to the movement of the moving unit;

[0115] a storage unit for storing the state quantity detected by the sensor unit and the movement relationship value acquired by the acquisition unit in correspondence with each other when the processing unit normally processes the workpiece while moving relative to the workpiece in association with the movement of the moving unit;

[0116] a calculation unit that calculates a normal range of the state quantity for each of the movement relationship values ​​based on the information stored in the storage unit; and

[0117] The determination unit, after calculating the normal range, determines whether the state quantity detected by the sensor unit is within the normal range based on a calculation result of the calculation unit when the processing unit moves relative to the workpiece while processing the workpiece as the moving unit moves.

[0118] (Composition 2)

[0119] In the abnormality determination device described in configuration 1,

[0120] The movement relationship value includes a movement speed of the moving part.

[0121] (Composition 3)

[0122] In the abnormality determination device described in Configuration 1 or Configuration 2,

[0123] The movement relationship value includes the movement direction of the moving part.

[0124] (Composition 4)

[0125] In the abnormality determination device described in any one of Configurations 1 to 3,

[0126] The moving part is a laser head provided in the laser processing machine.

[0127] The processing portion is a laser emitting portion of the laser head that emits laser light.

[0128] (Composition 5)

[0129] In the abnormality determination device described in any one of Configurations 1 to 4,

[0130] The calculation unit calculates a table indicating the normal range for each of the movement relationship values ​​based on the information stored in the storage unit.

[0131] The determination unit determines whether the state amount detected by the sensor unit is within the normal range based on the table.

[0132] (Composition 6)

[0133] In the abnormality determination device of any one of configurations 1 to 5,

[0134] The calculation unit derives a calculation formula for calculating the normal range of each of the movement relationship values ​​based on the information stored in the storage unit.

[0135] The determination unit determines whether the state quantity detected by the sensor unit is within the normal range based on the calculation formula.

[0136] (Composition 7)

[0137] In the abnormality determination device described in any one of Configurations 1 to 6,

[0138] The sensor unit detects at least one of analysis results of light quantity, temperature, sound, and image as the state quantity.

[0139] (Composition 8)

[0140] A laser processing machine comprises: a laser head that moves relative to a workpiece; a laser emitting unit that is arranged on the laser head and emits laser light to the workpiece while moving relative to the workpiece together with the laser head to process the workpiece; and an abnormality judgment device recorded in any one of configurations 1 to 7.

[0141] (Composition 9)

[0142] In the laser processing machine described in configuration 8,

[0143] The laser processing machine includes a head control device configured to stop processing of the workpiece when the determination unit determines that the state amount detected by the sensor unit is outside the normal range.

[0144] (Composition 10)

[0145] In the laser processing machine described in configuration 8,

[0146] The laser processing machine is provided with a head control device, and when the determination unit determines that the state quantity detected by the sensor unit is outside the normal range, the head control device changes the moving speed of the laser head until the state quantity detected by the sensor unit becomes within the normal range.

[0147] The above embodiments are described, but the technical scope of the present invention is not limited to the above embodiments. In addition, it is obvious to those skilled in the art that various changes or improvements can be applied to the above embodiments. It can be clearly seen from the description of the scope of the patent claims that the method of applying such changes or improvements is also included in the technical scope of the present invention. In addition, sometimes more than one of the elements described in the above embodiments is omitted. In addition, the elements described in the above embodiments can be appropriately combined. In addition, the execution order of each step shown in the embodiment can be implemented in any order as long as the result of the previous step is not used for the subsequent step. In addition, the actions in the above embodiments are described using "first", "second", "next", etc. for convenience, but they are not necessarily implemented in this order. In addition, as long as the law permits, the disclosure of all documents cited in the special application 2022-113303 of the Japanese patent application and the above embodiments, etc., are cited as part of the description of this article.

[0148] Explanation of symbols:

[0149] 1: laser processing machine; 2: processing device; 3: abnormality determination device; 12: laser head; 30: sensor; 31: abnormality determination unit; 40: acquisition unit; 41: storage unit; 42: calculation unit; 43: determination unit; 44: output unit.

Claims

1. An abnormality determination device for determining a machining abnormality of a workpiece in a machining device, wherein: The processing device comprises: a moving part that moves relative to the workpiece; and a processing part that is provided on the moving part and processes the workpiece while moving relative to the workpiece together with the moving part. The abnormality determination device is characterized by comprising: a sensor unit provided on the moving unit and moving relative to the workpiece together with the moving unit while detecting a state quantity related to processing of the workpiece by the processing device; an acquiring unit, which acquires a movement relationship value related to the movement of the moving unit; a storage unit for storing the state quantity detected by the sensor unit and the movement relationship value acquired by the acquisition unit in correspondence with each other when the processing unit normally processes the workpiece while moving relative to the workpiece in association with the movement of the moving unit; a calculation unit, which calculates a normal range of the state quantity for each of the movement relationship values ​​based on the information stored in the storage unit; as well as The determination unit, after calculating the normal range, determines whether the state quantity detected by the sensor unit is within the normal range based on a calculation result of the calculation unit when the processing unit moves relative to the workpiece while processing the workpiece as the moving unit moves.

2. The abnormality determination device according to claim 1, wherein: The movement relationship value includes a movement speed of the moving part.

3. The abnormality determination device according to claim 1, wherein: The movement relationship value includes the movement direction of the moving part.

4. The abnormality determination device according to claim 1, wherein: The moving part is a laser head provided in the laser processing machine. The processing portion is a laser emitting portion of the laser head that emits laser light.

5. The abnormality determination device according to claim 1, wherein: The calculation unit calculates a table indicating the normal range for each of the movement relationship values ​​based on the information stored in the storage unit. The determination unit determines whether the state amount detected by the sensor unit is within the normal range based on the table.

6. The abnormality determination device according to claim 1, wherein: The calculation unit derives a calculation formula for calculating the normal range of each of the movement relationship values ​​based on the information stored in the storage unit. The determination unit determines whether the state quantity detected by the sensor unit is within the normal range based on the calculation formula.

7. The abnormality determination device according to claim 1, wherein: The sensor unit detects at least one of analysis results of light quantity, temperature, sound, and image as the state quantity.

8. A laser processing machine, wherein: The laser processing machine comprises: a laser head that moves relative to a workpiece; a laser emitting unit that is disposed on the laser head and emits laser light to the workpiece while moving relative to the workpiece together with the laser head to process the workpiece; and an abnormality determination device that determines abnormality in the processing of the workpiece, characterized in that: The abnormality determination device comprises: A sensor unit is provided at the laser head and detects a state quantity of the laser processing machine while moving relative to the workpiece together with the laser head; An acquisition unit, which acquires a movement relationship value related to the movement of the laser head; a storage unit for storing the state quantity detected by the sensor unit and the movement relationship value acquired by the acquisition unit in correspondence with each other when the laser emitting unit moves relative to the workpiece and performs normal processing on the workpiece in association with the movement of the laser head; a calculation unit that calculates a normal range of the state quantity for each of the movement relationship values ​​based on the information stored in the storage unit; and After calculating the normal range, the determination unit determines whether the state quantity detected by the sensor unit is within the normal range based on the calculation result of the calculation unit when the laser head is moving relative to the workpiece and processing the workpiece.

9. The laser processing machine according to claim 8, wherein: The laser processing machine includes a head control device configured to stop processing of the workpiece when the determination unit determines that the state amount detected by the sensor unit is outside the normal range.

10. The laser processing machine according to claim 8, wherein: The laser processing machine is provided with a head control device, and when the determination unit determines that the state quantity detected by the sensor unit is outside the normal range, the head control device changes the moving speed of the laser head until the state quantity detected by the sensor unit becomes within the normal range.

11. A method for determining abnormality of machining a workpiece in a machining device, wherein: The processing device comprises: a moving part that moves relative to the workpiece; and a processing part that is provided on the moving part and processes the workpiece while moving relative to the workpiece together with the moving part. The above abnormality determination method is characterized by comprising: When the processing unit normally processes the workpiece while moving relative to the workpiece in accordance with the movement of the moving unit, the sensor unit that moves relative to the workpiece together with the moving unit detects a state quantity of the processing device; acquiring, by an acquiring unit, a movement relationship value related to the movement of the moving unit; storing, by a storage unit, the state quantity detected by the sensor unit and the movement relationship value acquired by the acquisition unit in correspondence with each other; By means of a calculation unit, based on the information stored in the storage unit, a normal range of the state quantity is calculated for each of the movement relationship values; After calculating the normal range, when the processing unit processes the workpiece while moving relative to the workpiece as the moving unit moves, it is determined whether the state quantity detected by the sensor unit is within the normal range based on the calculation result of the calculation unit.

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