Anomaly detection device, program, anomaly detection system and anomaly detection method

Abstract

An anomaly detection device (100) that detects an anomaly of a temperature sensor (200) in a machine tool (1), wherein the anomaly detection device (100) comprises: a temperature pattern storage unit (130) which stores at least one normal pattern indicating a temperature change relative to the machining time since a machining start time for each machining classification of the machine tool (1); a temperature data acquisition unit (110) that acquires temperature data since the start of the machining process, which is output by the temperature sensor (200) provided to the machine tool (1); a machining classification determination unit (120) that determines a machining classification of the machine tool (1) in accordance with a predetermined determination criterion; a comparison data acquisition unit (140) that extracts the at least one normal pattern relative to a processing classification determined by the processing classification determination unit (120) from the temperature pattern storage unit (130); a comparison unit (150) that compares the at least one normal pattern extracted by the comparison data acquisition unit (140) with a captured pattern that indicates a temperature change relative to the processing time according to the temperature data captured by the temperature data acquisition unit (110); and an anomaly determination unit (160) that determines the anomaly of a temperature sensor (200) based on a comparison result by the comparison unit (150).

Description

BACKGROUND OF THE INVENTIONField of the invention

[0001] The present invention relates to an abnormality determination apparatus, a program, an abnormality determination system, and an abnormality determination method that determine an abnormality in a temperature sensor of a machine tool. Related technology

[0002] In a machine tool, machining dimensional errors occur due to ambient temperature changes and heat generation from the machine tool, such as cutting heat. For this reason, thermal displacement compensation technology is used to compensate for the machining dimensional errors caused by machine tool heating. For example, as a technology that compensates for thermal displacement caused by heat generation from this machine tool, there is a technology that monitors the machine condition with multiple temperature sensors and estimates the thermal displacement. This usually involves installing a temperature sensor in the machine tool and estimating the thermal displacement amount from the temperature sensor output.In a factory automation (FA) environment where this temperature sensor is used, compared to normal applications, anomalies in the temperature sensor occur due to influences such as cutting fluid and chips. In the event of a temperature sensor deviation, it is not possible to obtain a normal temperature output from the temperature sensor. Using the output of a faulty temperature sensor will make it impossible to estimate an accurate heat displacement amount, and there is a risk of adversely affecting machining.

[0003] In the event of an abnormality, such as a disconnection in the temperature sensor, because the temperature sensor outputs an incorrect value, it is possible to determine whether the temperature sensor is abnormal. However, even if the temperature sensor outputs an incorrect value due to aging damage or the like, it is not possible to perform abnormality detection using the temperature sensor or the measuring device alone. In this context, for example, cited documents 1 to 3 disclose methods for detecting abnormalities in temperature sensors for thermal displacement compensation of machine tools.With the methods described in cited documents 1 and 2, when a plurality of temperature sensors are arranged on a machine tool and the variation in the detected temperatures of the temperature sensors exceeds a limit value, or when a limit value is exceeded due to the estimation of the outputs of other temperature sensors from the output of one temperature sensor, the temperature is determined to be abnormal. Furthermore, with the method described in cited document 1, a plurality of temperature sensors measuring temperatures at a plurality of locations are arranged on the machine tool, and an estimated temperature is calculated for the temperature of a location measurable by one temperature sensor based on the measured temperatures of the plurality of other temperature sensors.

[0004] Patent Document 4 describes a processing machine with a temperature sensor. After the measured temperature value is received by a computer, it is processed, e.g., compared with previously specified reference values. If the temperature comparison value is critical, the computer can control a display to indicate "Please change tool." Patent document 1: JP 2008 - 14941515 Patent document 2: JP 2008 - 142 844 Patent document 3: JP 2015 - 104 765 Patent document 4: EP 2 103 378 A1 SUMMARY OF THE INVENTION

[0005] However, the methods described in Patent Documents 1 to 3 all require the installation of a plurality of temperature sensors on the machine tool. Furthermore, a technique that installs a plurality of temperature sensors at the same location has been considered for anomaly detection. However, this technique increases the number of temperature sensors or measuring devices, thus increasing costs.

[0006] The present invention aims to provide an abnormality determination apparatus, a program, an abnormality determination system, and an abnormality determination method that can easily detect abnormalities in temperature sensors of a machine tool without cost.

[0007] An abnormality determination device (e.g., the later-described “anomaly determination device 100”) according to a first aspect of the present invention, which determines the abnormality of a temperature sensor (e.g., the later-described “temperature sensor 200”) in a machine tool (e.g., the later-described “machine tool 1”), comprises: a temperature pattern storage unit (e.g., the later-described “temperature storage unit 130”) that stores a normal pattern indicating a temperature change relative to the machining time for a machining classification of the machine tool; a temperature data acquisition unit (e.g., the later-described “temperature data acquisition unit 110”) that acquires temperature data output from the temperature sensor provided to the machine tool; a machining classification determination unit (e.g.,the later-described “machining classification determination unit 120”) that determines a machining classification of the machine tool; a comparison data acquisition unit (e.g., the later-described “comparison data acquisition unit 140”) that extracts the normal pattern relative to a machining classification determined by the machining classification determination unit from the temperature pattern storage unit; a comparison unit (e.g., the later-described “comparison unit 150”) that compares the normal pattern extracted by the comparison data acquisition unit with a detected pattern indicating a temperature change relative to the machining time according to the temperature data acquired by the temperature data acquisition unit; and an abnormality determination unit (e.g.,the “anomaly determination unit 160” described later) that determines the anomaly of a temperature sensor based on a comparison result of the comparison unit.

[0008] According to a second aspect of the present invention, in the abnormality determination device as described in the first aspect, the comparison unit may compare at least any absolute value of the temperature at any time, the relative change amount of the temperature since a machining start time, and a change rate of the temperature per time.

[0009] According to a third aspect of the present invention, the abnormality determination device as described in the first or second aspect may further include a pattern updating unit (e.g., the “pattern updating unit 180” described later) that causes the detected pattern to be stored as a normal pattern in the temperature pattern storage unit when the temperature sensor is not determined to be abnormal via the abnormality determination unit.

[0010] According to a fourth aspect of the present invention, the abnormality determination device as described in the first or second aspect may further comprise a pattern updating unit that causes the detected pattern in the temperature pattern storage unit to be assigned to the machining classification as a normal pattern if the comparison data acquisition unit is unable to extract the normal pattern relative to the machining classification determined by the machining classification determination unit.

[0011] According to a fifth aspect of the present invention, in the abnormality determination device as described in any one of the first to fourth aspects, the abnormality determination device of the machine tool may be provided and further include: a notification unit (e.g., the "notification unit 170" described later) that notifies an abnormality when determined as an abnormal temperature sensor via the abnormality determination unit; and a machining control unit that controls the machining operation of the machine tool based on a notification by the notification unit.

[0012] A sixth aspect of the present invention may be a program for making a computer function as an abnormality determining device as described in any one of the first to fifth aspects.

[0013] An abnormality determination system according to a seventh aspect of the present invention includes the abnormality determination device as described in the fifth aspect, in which the abnormality determination device can be communicatively connected to a plurality of other machine tools, and the temperature pattern storage unit can store the normal pattern for machining classification of each of the plurality of other machine tools.

[0014] An abnormality determination system (e.g., the "anomaly determination system 1000" described later) according to an eighth aspect of the present invention includes the abnormality determination device (e.g., the "anomaly determination device 100-2" described later) as described in any one of the first to fourth aspects, wherein the abnormality determination device may be a server connected to a plurality of the machine tools, and the temperature pattern storage unit may store the normal pattern for machining classification of each of the plurality of machine tools.

[0015] An abnormality determination method according to a ninth aspect of the present invention for a temperature sensor (for example, the “temperature sensor 200” described later) in a machine tool (for example, the “machine tool 1” described later) includes: determining whether a temperature sensor is abnormal via a computer (for example, the “anomaly determination device 100” described later) provided with a temperature pattern storage unit (for example,the later-described "temperature pattern storage unit 130") is provided which stores a normal pattern indicative of a temperature change relative to the machining time for a machining classification of the machine tool, comparing a detected pattern indicative of a temperature change relative to the machining time according to the temperature data output from the temperature sensor provided to the machine tool relative to an equivalent machining classification and the normal pattern stored in the temperature pattern storage unit.

[0016] According to the present invention, it is possible to provide an abnormality determination apparatus, a program, an abnormality determination system, and an abnormality determination method that can easily detect the abnormality of a temperature sensor in a machine tool without incurring costs. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram showing the basic configuration of a machine tool of the present embodiment; Fig. 2 is a block diagram of the machine tool of the present embodiment; Fig. 3 is a view showing an example of a temperature pattern storage unit of the machine tool of the present embodiment; Fig. 4 is a view illustrating the relationship between a machining start time and temperature according to the present embodiment; Fig. 5 is a flowchart showing the processing of determining an abnormality by an abnormality determining device of the machine tool according to the present embodiment; and Fig. 6 is a schematic diagram illustrating the basic configuration of an abnormality determination system according to a modified embodiment. DETAILED DESCRIPTION OF THE INVENTION (Embodiment)

[0017] First, a summary of one embodiment of the present invention will be explained. The present embodiment relates to a system for determining an abnormality in a temperature sensor by comparing a detected pattern according to temperature data from temperature sensors provided to machine tools that perform machining processes and a normal pattern indicating the temperature change relative to the machining time in a previously stored machining classification. The detected pattern indicates the temperature change relative to the machining time from the detected temperature data.

[0018] Next, the configuration of a machine tool 1 which is the present embodiment will be explained by referring to the Fig. 1 to 3: The Fig. The machine tool 1 shown in FIG. 1 is a machine that performs predetermined machining, such as cutting, on a workpiece such as a component, based on operation commands issued from a numerical control device (not shown). In this example, the machine tool 1 is explained as having three translational axes (X, Y, Z axes) orthogonal to each other as drive shafts; however, it is not limited to this.

[0019] A temperature sensor 200 is mounted on the machine tool 1. Here, a configuration in which each of the machine tools 1 is provided with a temperature sensor 200 is shown as an example in Fig. 1; however, there is no limitation on the number of temperature sensors 200 that can be provided to the machine tool 1. The temperature sensor 200 detects the temperature of the machine tool 1. The temperature sensor 200 tends to absorb or barely absorb the influence of heat generation depending on the mounting position of the machine tool 1. For example, the temperature sensor 200 mounted on the motor and at a location close to it tends to absorb the influence of heat generation. On the other hand, the temperature sensor 200 mounted at a position sufficiently distant from the motor or a terminal position thereof hardly absorbs the influence of heat generation.In addition, the temperature sensor 200, which is mounted at a position sufficiently far from the motor or a terminal position thereof and does not receive the influence of cutting fluid, will hardly receive the influence of heating and cooling.

[0020] The temperature sensor 200 is a thermistor or the like and outputs a temperature detection signal. The machine tool 1 digitizes the temperature detection signal using a known method and obtains temperature data representing the temperature with a numerical value.

[0021] As in Fig. As shown in Figure 2, the machine tool 1 includes an abnormality determination device 100. The abnormality determination device 100 acquires temperature data from the temperature detection signal of the temperature sensor 200 and compares a detected pattern indicating the temperature change relative to the machining time from the acquired temperature data with a normal pattern stored in a temperature pattern storage unit 130 indicating the temperature change relative to the machining time of the machining classification of a specific machine tool. The abnormality determination device 100 then determines an abnormality of the temperature sensor 200 based on the comparison results.The abnormality determination device 100 includes a temperature data acquisition unit 110, a machining classification determination unit 120, a temperature pattern storage unit 130, a comparison data acquisition unit 140, a comparison unit 150, an abnormality determination unit 160, a notification unit 170, and a pattern updating unit 180.

[0022] The temperature data acquisition unit 110 acquires temperature data based on the temperature detection signal sent from the temperature sensor 200 provided to the machine tool 1. The machining classification determination unit 120 determines the machining classification according to a predetermined, predefined criterion. The predetermined criterion is based, for example, on the program number of an executed program, operating state data relating to an operating state, a machining time, or the like, or a combination thereof; however, these are only examples and are not intended to be limited thereto. The operating state data is, for example, an internal command signal of a numerical control device (not shown) that is output at predetermined sampling times (e.g.,1 msec) is recorded in chronological sequence, control data of the feed axis (not shown) recorded by the motor of machine tool 1, spindle control data related to the spindle, etc.

[0023] The temperature pattern storage unit 130 stores the machining classification to be assigned, the expiration time and the temperature data as shown in Fig. 3. Here, the abnormality determination device 100 can graphically express the normal pattern indicating the temperature change relative to the processing time from the elapsed time and temperature data of the processing classification stored in the temperature pattern storage unit 130. For example, Fig. 4 shows a normal pattern based on the processing classification's elapsed time and temperature data, which is stored in the temperature pattern storage unit 130 as a graph Gmaster. The temperature pattern storage unit 130 can further store this normal pattern to link it to the processing classification, elapsed time, and temperature data.

[0024] The comparison data acquisition unit 140 acquires the normal pattern relative to the machining classification determined by the machining classification determination unit 120. Specifically, the comparison data acquisition unit 140 can acquire the normal pattern by extracting temperature data for each expiration time from the temperature pattern storage unit 130. At this time, the machining classification of the normal pattern to be acquired can be equivalent to the machining classification of the machine tool 1 with acquired temperature data. The equivalent machining classification is determined based on a predetermined reference set in advance. The user can arbitrarily set the predetermined reference in advance.Note that if the normal pattern itself is stored in the temperature pattern storage unit 130, it is sufficient for the comparison data acquisition unit 140 to extract the stored normal pattern. Hereinafter, unless otherwise stated, a machining classification that corresponds to the predetermined reference set in advance is referred to as an equivalent machining classification.

[0025] The comparison unit 150 compares the normal pattern acquired by the comparison data acquisition unit 140 with the acquired pattern indicating the temperature change relative to the processing time from the temperature data acquired by the temperature data acquisition unit 110. The acquired pattern can also be expressed as a graph, similar to the normal pattern. For example, the graph Gb of Fig. 4 the acquired pattern. The comparison unit 150 can compare the absolute value of the temperature at any time or the relative amount of change in the temperature since the start of processing. Furthermore, the comparison unit 150 can compare the rate of change of the temperature per unit time.

[0026] The abnormality determination unit 160, where the difference is at least the reference value as a result of the comparison by the comparison unit 150, determines that the temperature sensor 200 is abnormal. For example, if it is determined to be abnormal via the abnormality determination unit 160, the notification unit 170 reports the abnormality of the temperature sensor 200 on a display (not shown) of the machine tool 1.

[0027] The pattern update unit 180 causes the acquired pattern to be stored as a normal pattern in the temperature pattern storage unit 130 if it is not possible to acquire a normal pattern relative to the determined machining classification in the processing by the comparison data acquisition unit 140. Furthermore, the pattern update unit 180 causes the acquired pattern to be stored as a normal pattern in the temperature pattern storage unit 130 if it is not determined as abnormal by the abnormality determination unit 160.

[0028] The functional blocks of the anomaly determination device 100 have been explained above. Next, the implementation method of these functional blocks will be explained. To implement these functional blocks, the anomaly determination device 100 includes an arithmetic processing unit such as a CPU (Central Processing Unit). Furthermore, the anomaly determination device 100 includes an auxiliary storage device such as a hard disk for storing various programs for control, including the anomaly determination program, and a main storage device such as RAM (Random Access Memory) for storing data temporarily required when the arithmetic processing unit executes a program.

[0029] Then, the arithmetic processing unit in the anomaly determination device 100 reads an application or operating system from the auxiliary storage and performs arithmetic processing based on this application or operating system while expanding the read application or operating system into the main storage device. Furthermore, the anomaly determination device 100 controls various hardware equipped therewith based on the operation result. The functional blocks of the present embodiment are thus realized. In other words, the present embodiment can be implemented through the cooperation of hardware and software.

[0030] Next, the processing of determining the abnormality of the temperature sensors 200 will be explained. Fig. 5 is a flowchart illustrating the abnormality determination processing by the abnormality determination device 100 of the machine tool 1. In step S (hereinafter, step S is simply referred to as S) 10 in Fig. 5, the temperature data acquisition unit 110 of the anomaly determination device 100 acquires temperature data based on the temperature detection signal output from the temperature sensor 200. At this time, the temperature data acquisition unit 110 continuously acquires temperature detection signals sent from the temperature sensors 200 at an appropriate timing.

[0031] In S11, the machining classification determination unit 120 determines the machining classification of the machine tool 1. The machining classification determination unit 120 can determine the machining classification according to a predetermined, predefined criterion. In S12, the comparison data acquisition unit 140 references the temperature pattern storage unit 130 and acquires the normal pattern of the machining classification corresponding to the determined machining classification. The normal pattern acquired by the comparison data acquisition unit 140 is not limited to one. If a plurality of normal patterns are stored relative to one machining classification, the comparison data acquisition unit 140 acquires a plurality of normal patterns.

[0032] In S13, the comparison data acquisition unit 140 judges whether or not it is possible to acquire a normal pattern. If data corresponding to the target machining classification is stored in the temperature pattern storage unit 130, the comparison data acquisition unit 140 can acquire a normal pattern. On the other hand, in a phase where the acquisition of temperature data from this machine tool 1 is rarely performed, the data corresponding to the target machining classification must not be stored in the temperature pattern storage unit 130. In this case, the comparison data acquisition unit 140 cannot acquire a normal pattern. If a normal pattern can be acquired (S13: YES), the comparison data acquisition unit 140 switches the processing to S14. On the other hand, if it is not possible to acquire a normal pattern (S13: NO), the comparison data acquisition unit 140 switches the processing to S17.

[0033] In S14, the comparison unit 150 performs pattern comparison processing, comparing the acquired pattern indicating the temperature change relative to the machining time according to the temperature data acquired by the processing of S10 and the normal pattern acquired by the processing of S12. Here, the comparison unit 150 may perform a comparison between the acquired pattern and the normal pattern according to the absolute values ​​of the temperatures. Furthermore, the comparison unit 150 may perform a comparison by setting the absolute temperature change since the machining start time to 0, with the temperature during the machining start time as 0. Furthermore, the comparison unit 150 may perform the comparison between the acquired pattern and the normal pattern by setting the temperature change over time.

[0034] In S15, the abnormality determination unit 160 judges whether the result of the comparison between the detected pattern and the normal pattern is abnormal or not. Here, a concrete example is given by Fig. 4 explained. Fig. 4 shows a detected pattern and a normal pattern by the temperature magnitudes of a specific machining class. Here, the graph Gmaster is the normal pattern, and the graphs Ga-Gc are detected patterns. In this case, when the detected pattern is graph Gb, the difference from the graph Gmaster is small. For this reason, the abnormality determination unit 160 judges that the comparison result is not abnormal. On the other hand, when the detected pattern is graph Ga or graph Gc, the difference from the graph Gmaster is large. For this reason, the abnormality determination unit 160 judges the comparison result as abnormal. The abnormality determination unit 160 may make a judgment as to whether the comparison result is abnormal or not, for example, based on whether the difference is at least a reference value or not. If the comparison result is abnormal (S15: YES), the abnormality determination unit 160 switches the processing to S16.On the other hand, if the result of the comparison is not abnormal (S15: NO), the abnormality determination unit 160 switches the processing to S17.

[0035] In S16, the notification unit 170 issues a notification that the temperature sensor 200 is abnormal. For example, the notification unit 170 may display the abnormality of the temperature sensor 200 on a display (not shown) of the machine tool 1. Afterward, the control unit (not shown) that integrally controls the machine tool 1 terminates the current machining. In S17, the pattern update unit 180 causes the acquired pattern data indicating the temperature change relative to the machining time according to the temperature data acquired through the processing of S10 to be stored in the temperature pattern storage unit 130 as a normal pattern. Subsequently, the control unit of the machine tool 1 terminates the current machining.

[0036] This makes it possible to easily detect abnormalities of a temperature sensor 200 provided to the machine tool 1 at no cost by comparing the detected pattern based on the output of the temperature sensor 200 and the normal pattern of a machining classification corresponding to the detected pattern.

[0037] For example, by comparing the acquired pattern and the normal pattern according to the temperature amounts, it can be determined to be abnormal if the difference in the amounts is at least the reference value. In addition, by comparing the acquired pattern and the normal pattern according to the absolute amount of temperature change since the start of processing, it is possible to determine whether it is abnormal if the difference in the absolute amount of change is at least the reference value. In addition, by comparing the acquired pattern and the normal pattern according to the temperature change rate per time, it is possible to discriminate as abnormal if the difference in the change rate is at least the reference value.

[0038] The abnormality determination device 100 can accumulate many normal patterns because the detected pattern is stored in the temperature pattern storage unit 130 as a normal pattern when it is determined not to be abnormal in comparison. The abnormality determination device 100 causes the detected pattern to be stored in the temperature pattern storage unit 130 as a normal pattern when a normal pattern relative to a processing classification is not stored in the temperature pattern storage unit 130. For this reason, it is possible to accumulate a normal pattern that can be the comparison target for the next comparison.

[0039] The programs, including the anomaly determination program used in the present invention, can be stored on various types of non-transitory, computer-readable media and provided to a computer. Non-transitory, computer-readable media include various types of tangible storage media. Examples of non-transitory computer-readable media are magnetic media (e.g., flexible disks, magnetic tape, hard disk drive), magneto-optical recording media (e.g., magneto-optical disk), CD-ROM (Read Only Memory), CD-R, CD-R / W, and semiconductor memories (e.g., mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), Flash ROM, RAM (Random Access Memory)). Furthermore, the program can be provided to a computer via various types of temporarily computer-readable media. Examples of transitorily computer-readable media include electrical signals, optical signals, and electromagnetic waves.Temporarily computer-readable media can deliver programs to a computer over wired communications such as electrical wires and fiber optics, or over a wireless communications path.

[0040] Furthermore, the above embodiment is a preferred embodiment of the present invention; however, it is not intended to limit the scope of the present invention to the above embodiment, and the realization is possible in a form achieved by various changes within a scope that does not deviate from the gist of the present invention. (Modified Example 1)

[0041] In the aforementioned embodiment, a configuration that notifies when the temperature sensor 200 is determined to be abnormal was explained as an example; however, it is not limited to this. It can be configured so that the machining controller of the machine tool 1 controls the machining operation based on the notification from the notification unit 170. Specifically, the machining controller of the machine tool 1 can stop the machining operation. Configured in this way, this is done without estimating the thermal absolute displacement value from the output of a faulty temperature sensor 200, and machining that previously exerts a negative influence can be prevented. (Modified Example 2)

[0042] In the aforementioned embodiment, processing by one machine tool 1 was explained, but this is not limited to this. For example, when the unit types of the plurality of machine tools are equivalent and equivalent machining operations are performed, it is possible to determine abnormalities through the abnormality determination device (server) connected to the plurality of machine tools. At this time, equivalent unit types are judged in advance based on a predetermined reference set. Here, the unit type indicates, for example, the model number, version, options, etc. of the machine tool. For example, equivalent unit types refer to the same unit type and may have slight version differences such as differences in options. Note that this is an example and is not limited to this.The user can arbitrarily set the predefined reference in advance. Furthermore, equivalent machining operations are judged based on the predefined reference value. Equivalent machining operations include, for example, equivalent machining programs and the ability to perform equivalent machining simultaneously across equivalent machining programs. Here, equivalent machining programs include, for example, machining programs that have version differences in the program but essentially perform the same machining. Fig.6 refers to the abnormality determination system 1000, in which an abnormality determination device 100-2 (server) connected to a plurality of machine tools 4 via a communication network N determines an abnormality for the temperature sensors of the plurality of machine tools 4 (4a, 4b, ..., 4n). Here, the communication network N is, for example, a LAN (Local Area Network) established within a factory, an Internet, a public telephone network, etc., or a combination thereof. The specific communication method of the communication network N and whether it is a wired connection or a wireless connection, etc., are not particularly limited. Moreover, when the branch number (-1 or -2) of the temperature sensors 200 mounted on each machine tool 4 is the same, it indicates that they have the same mounting position.Then, the abnormality determination device 100-2 can determine the abnormality of the temperature sensor 200 of the machine tool 4 using a normal pattern of the temperature sensor 200 of another machine tool 4 with the same mounting position of the temperature sensor 200 of this machine tool 4. Thus, it is possible to share the normal pattern with a plurality of machine tools 4 through the abnormality determination system 1000. (Modified Example 3)

[0043] Additionally, at least one other machine tool may be communicatively connected to the machine tool 1 of the aforementioned embodiment, and the temperature sensor abnormality may be determined by receiving temperature data associated with the machining classification and timing of the other machine tools. In this case, if the mounting position of the temperature sensor of the other at least one machine tool is the same as the mounting position of the temperature sensor 200 of the machine tool 1, it is advantageous to use the normal pattern of the machine tool 1 for the detected pattern of the other machine tool.In addition, in the case of the mounting position of temperature sensors, the unit type, and the machining operation of other machine tools different from the machine tool 1, it is possible to use the normal pattern of the temperature pattern storage by a machine tool having the same mounting position, the same unit type, and the same machining operation, which is advantageous as long as the mounting position, the unit type, and the machining operation are further stored to be allocated in the temperature pattern storage unit. DESCRIPTION OF REFERENCE SYMBOLS 1, 4, 4a, 4b,.... 4n machine tool 100, 100-2 Anomaly Determination Device 110 Temperature data acquisition unit 120 Processing Classification Determination Unit 130 Temperature pattern storage unit 140 Comparison data acquisition unit 150 comparison units 160 Anomaly Determination Unit 170 Communication unit 180 pattern update unit 200, 200a-1, 200a-2, 200b-1,... , 200n-2 temperature sensor 1000 Anomaly Determination System

Claims

[1] An abnormality determination device (100) that determines an abnormality of a temperature sensor (200) in a machine tool (1), the abnormality determination device (100) comprising: a temperature pattern storage unit (130) that stores at least one normal pattern indicating a temperature change relative to machining time since a machining start time for each machining classification of the machine tool (1); a temperature data acquisition unit (110) that acquires temperature data since the machining start time output from the temperature sensor (200) provided to the machine tool (1); a machining classification determining unit (120) that determines a machining classification of the machine tool (1) in accordance with a predetermined determination criterion set in advance; a comparison data acquisition unit (140) that extracts the at least one normal pattern relative to a machining classification determined by the machining classification determination unit (120) from the temperature pattern storage unit (130); a comparison unit (150) that compares the at least one normal pattern extracted by the comparison data acquisition unit (140) with a detected pattern indicating a temperature change relative to the processing time according to the temperature data acquired by the temperature data acquisition unit (110); and an abnormality determination unit (160) that determines the abnormality of a temperature sensor (200) based on a comparison result by the comparison unit (150). [2] The abnormality determination device (100) according to claim 1, wherein the machining classification determination unit (120) determines the machining classification based on information regarding a program executed by the machine tool, information regarding an operating state of the machine tool, and / or a length of machining time since a machining start time. [3] The abnormality determination device (100) according to claim 1 or 2, wherein the comparison unit (150) compares at least one of an absolute value of the temperature at each time, a relative change amount of the temperature since a machining start time, and a change rate of the temperature per time. [4] The abnormality determination device (100) according to any one of claims 1 to 3, further comprising a pattern updating unit (180) that causes the detected pattern to be stored in the temperature pattern storage unit (130) as a normal pattern in a case where the temperature sensor (200) is determined to be non-abnormal via the abnormality determination unit (160). [5] The abnormality determination device (100) according to any one of claims 1 to 3, further comprising a pattern updating unit (180) that causes the acquired pattern in the temperature pattern storage unit (130) to be assigned to the machining classification as the normal pattern in a case where the comparison data acquisition unit (140) is unable to extract the normal pattern relative to the machining classification determined by the machining classification determination unit (120). [6] The abnormality determination device (100) according to any one of claims 1 to 5, wherein the abnormality determination device is provided to the machine tool (1) and further comprises: a notification unit (170) that notifies an abnormality in a case where it is determined via the abnormality determination unit (160) that the temperature sensor (200) is abnormal; and a machining control unit that controls the machining operation of the machine tool (1) based on a notification by the notification unit (170). [7] A computer-readable medium encoded with a program for causing a computer to function as the anomaly determination device (100) according to any one of claims 1 to 6. [8] An anomaly determination system comprising the anomaly determination device (100) according to claim 5, wherein the anomaly determination device (100) is communicatively connected to a plurality of other machine tools, and wherein the temperature pattern storage unit (130) stores the at least one normal pattern for each machining classification of each of the plurality of other machine tools. [9] An anomaly determination system (1000) comprising the anomaly determination device (100-2) according to any one of claims 1 to 5, wherein the abnormality determination device (100-2) is a server communicatively connected to a plurality of the machine tools (4), and wherein the temperature pattern storage unit (130) stores the at least one normal pattern for each machining classification of each of the plurality of machine tools (4). [10] An abnormality determination device (100) that determines an abnormality of a temperature sensor (200) in a machine tool (1), the abnormality determination device (100) comprising: a temperature pattern storage unit (130) that stores a normal pattern indicating a temperature change relative to machining time for machining classification of the machine tool (1); a temperature data acquisition unit (110) that acquires temperature data output from the temperature sensor (200) provided to the machine tool (1); a machining classification determining unit (120) that determines a machining classification of the machine tool (1); a comparison data acquisition unit (140) that extracts the normal pattern relative to a machining classification determined by the machining classification determination unit (120) from the temperature pattern storage unit (130); a comparison unit (150) that compares the normal pattern extracted by the comparison data acquisition unit (140) with a detected pattern indicating a temperature change relative to the processing time according to the temperature data acquired by the temperature data acquisition unit (110); and an abnormality determination unit (160) that determines the abnormality of a temperature sensor (200) based on a comparison result by the comparison unit (150); and a pattern updating unit (180) that causes the acquired pattern to be stored in the temperature pattern storage unit (130) to be linked to the machining classification as a normal pattern if the comparison data acquiring unit (140) is unable to extract the normal pattern concerning the machining classification determined by the machining classification determining unit (120). [11] An abnormality determination method for a temperature sensor (200) in a machine tool (1), the method comprising: determining whether a temperature sensor (200) is abnormal via a computer (100) provided with a temperature pattern storage unit (130) that stores at least one normal pattern indicating a temperature change relative to the machining time since a machining start time for each machining classification of the machine tool (1), determining a machining classification of the machine tool (1) in accordance with a predetermined determination criterion set in advance, and comparing a detected pattern indicating a temperature change relative to the machining time according to the temperature data since the machining start time output from the temperature sensor (200) provided on the machine tool,and the at least one normal pattern relating to the thus determined processing classification stored in the temperature pattern storage unit (130).

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