JP7510583B2 - Processing status display device - Google Patents

Description

The present invention relates to a machining status display device that displays a graph in real time of the status of a machining tool, etc., when machining a workpiece with the machining tool of a machine tool, and simultaneously displays a graph that overlays reference data based on past data, etc.

In rotary processing equipment such as cutting equipment, when considering the product precision of the workpiece, manufacturing efficiency, and yield of the processed product, it is necessary to evaluate the condition of the processing tool (hereinafter also referred to as "tool") during processing, such as evaluation of wear, fatigue, breakage, chatter, etc. Conventionally, tool evaluation has been performed based on evaluation criteria that are generalized by equipment manufacturers or tool manufacturers for each equipment or tool, or academically standardized evaluation criteria, and real-time verification of the actual tool during processing has not been possible.

In response to this, the applicant has developed and provided a tool holder unit that can measure the numerical changes in evaluation factors such as temperature, acceleration (vibration), and stress, which are indicators of the tool's condition during machining, and has also developed and provided a technology for predicting abnormalities such as tool breakage based on the results of this measurement (see Patent Documents 1 to 3). This technology has the advantage that it can detect the numerical changes in evaluation factors of tools, etc. during machining in real time, display them in real time in a window on the display of an external device (such as a personal computer) that can wirelessly communicate with the tool or machine tool, and detect abnormalities. For example, it is possible to monitor acceleration during ball end mill machining and detect the occurrence of so-called "chatter" in machining processes where machining accuracy is particularly prone to decline.

Being able to monitor the time-series changes in the numerical values of the tool's evaluation factors during machining on a display in this way has the great advantage of allowing users to intuitively see changes in the tool's condition. However, there are currently no clear indicators that users can use to actually predict abnormalities, such as whether the current tool condition is approaching its limit of damage, or whether it is in a state that will reduce machining accuracy, and users are forced to rely on empirical rules.

In addition, the process that leads to a tool abnormality and the circumstances under which the abnormality occurs vary depending on the tool, machining process, and machine tool, and cannot be evaluated simply for each tool.

International Publication WO2015-022967 International Publication WO2016-136919 JP 2018-54611 A

The present invention was created in consideration of the above situation, and aims to provide a machining status display device that can display the actual changes in the machining status during each machining process of each machine tool's machining tool (tool) in real time on a display, with respect to the numerical changes in temperature, acceleration, and stress in machining tools such as machine tool tools, while also overlaying and displaying the reference data for that machining process.

The processing state display device of the present invention comprises:
A measuring means for measuring in real time a temperature and/or an acceleration of a machining tool at the tip of the machine tool during a machining process, and /or other physical quantity data including an output of a rotary spindle of the machine tool;
a real-time data display means for displaying the physical quantity data measured in real time by the measuring means in a time-series real-time graph in a window capable of displaying a graph within a desired time range;
a reference data extraction means for extracting reference data of time series of physical quantity data for the same processing tool and processing process as those measured by the measurement means;
and a reference data display means for displaying a reference graph in the window by superimposing the time-series reference data extracted by the reference data extraction means on the processing step being measured by the measurement means.

According to the machining state display device of the present invention, the state of the machining tool (hereinafter also referred to as "tool") during machining of the machine tool can be measured in real time, and the standard data of the same tool and the same machining, which can be compared at a glance, can be displayed in a graph and superimposed on the real-time display graph displayed in the window. With this machining state display device, when machining a workpiece using a machine tool, the status of the tool can be visually confirmed in real time in the graph display while at the same time comparing and verifying with the standard graph data for the same tool and the same machining, and it is possible to instantly understand whether the tool is approaching its breakage limit, etc. As a result, it is possible to perform machining while avoiding in advance the stoppage of the machine tool due to tool breakage, which significantly improves machining efficiency and reduces production costs. In addition, even inexperienced operators can easily manage the machine tool, and management of the entire factory is also made easier.

It is also preferable that the measurement means sets the measurement start condition to when the workpiece is actually started to be processed by the tool during operation of the machine tool, and sets the measurement end condition to when the workpiece is actually no longer processed by the tool.

In addition to the process of actually machining the workpiece, the operation of a machine tool includes processes such as calling up the desired tool, starting and stopping the rotation of the rotating spindle, approaching the tool to the workpiece, and retracting the tool from the workpiece. If measurements are performed at stages of the operation of the machine tool other than the process of actually machining the workpiece, there is a possibility that extra peaks other than those that occur during the actual machining stage will occur, such as an increase in the load meter value when rotation starts or stops. Therefore, with this machining status display device, physical quantity data is measured only when the workpiece is actually being machined, allowing the user to grasp the accurate machining status from the real-time display graph.

The start condition for measurement by the measuring means, i.e., when the tool has actually started machining the workpiece, may be determined when the value of a macro common variable that is used in an NC program that controls the operation of the machine tool and indicates the machining state, changes to a value other than zero, and the end condition for measurement by the measuring means, i.e., when the tool is not actually machining the workpiece, may be determined when the value of the macro common variable changes to zero.

As will be described in detail later, the variables of the NC program that controls the operation of the machine tool include a macro common variable (e.g., #100) that indicates the machining state of the machine tool; when the value of this macro common variable is zero (e.g., #100 = 0), control is executed to result in a state other than machining (e.g., starting rotation of the rotating spindle or approaching the workpiece), and when the value of the macro common variable is non-zero (e.g., #100 = 1), control is executed to perform actual machining (e.g., cutting with tool 1). Therefore, if the timing for determining the start and stop of machining is determined when the value of this macro common variable changes to non-zero and when it changes to zero, a correct real-time display graph with unnecessary peaks removed can be output simply by reading the control information.

In addition, the physical quantity data measured by the measuring means is stored or updated in the main body of the machine tool or in a storage means external to the machine tool,
The reference data extraction means can extract, as reference data, physical quantity data of the same processing tool and the same processing from the physical quantity data stored in the storage means.

The reference graph, which is displayed overlaid on the real-time graph that shows the status during processing, is based on data from the same processing tool and the same processing from past data stored in the storage means. This makes it possible to instantly compare and verify the actual status measured in the past with the current status for the same processing in real time.

Furthermore, when the machining tool is changed during operation of the machine tool, the reference data extraction means extracts the changed machining tool and the same machining tool and physical quantity data of the machining as those executed by the changed machining tool as new reference data;
The reference data display means may have a function of deleting the reference graph already displayed in the window and displaying a reference graph of the new reference data when the machining tool is changed during operation of the machine tool.

In this machining status display device, when the machining tool is replaced during the entire machining process, the reference graph is reset from the display in the window each time the machining tool is changed, and the reference data corresponding to each machining tool is displayed in a graph. This means that the real-time graph always displays the reference graph for the machining tool currently being used for machining.

The reference data extraction means can also extract reference data for macro common variables whose values are other than 0 using the same processing tool from the physical quantity data stored in the storage means.

As described above, when this machining status display device reads whether the macro common variable value of the NC program that represents the machining status of the machine tool is zero or non-zero to control real-time measurement and graph display, it is possible to display different reference data depending on the value of the macro common variable (= non-zero).

The storage means may store the physical quantity data measured by the measuring means during all machining steps of the machine tool or during each machining step among all machining steps, and may update the physical quantity data when the physical quantity data for all machining steps or each machining step using the same machining tool has already been stored.

The reference data stored in the storage means can be reacquired later, either as the entire machining process or as a part of the machining process. Therefore, if the machining content of the machine tool changes, the reference data can be reacquired, and already acquired machining content can be updated to create more accurate reference data.

The physical quantity data measured by the measuring means in the storage means is updated by weighting the physical quantity data for the same processing tool and the same processing process stored in the storage means in a predetermined manner, and outputting the data as a group of predicted abnormal or normal data according to each operating condition for the same processing tool and the same processing process, and the predicted abnormal or normal data using a neural network can be used as reference data.

Specifically, the reference data display means displays a threshold value as a preset reference data or a threshold value as a reference data extracted by the reference data extraction means in the window.

Thresholds can be set for the reference data and displayed in a graph. By displaying the thresholds, it is possible to see at a glance how close the current machining state is to reaching the limit of tool life, etc.

Furthermore, the real-time data display means and the reference data display means may be adjusted to display the same machining amount in the NC program of the machine tool for the same machining tool and the same machining process on the same time axis.

In this machining status display device, in order to adjust the time axis to match the machining status, the horizontal axis of the graph is adjusted by expanding/contracting or aligning the time axis so that the same machining amount is on the same time axis, based on the parameters of the NC program. Machining time in machine tools varies even with the same tool and machining process due to factors such as changes in the amount of compensation due to tool wear and feed overrides, but when comparing data for the same tool and the same machining, if the machining time varies, the time axis will vary between processes from the start to the end of machining, making it difficult to make detailed comparisons. To improve this problem, this machining status display device adjusts the time axis (horizontal axis) of the graph based on the parameters of the NC program.

In this specification, the same machining tool and the same machining process are of the same type that a person skilled in the art would judge to be the same machining tool and the same machining process, and include those made by different manufacturers or machine tools.

The machining state display device of the present invention can display a graph of the status of the machining tool, etc. in real time when machining a workpiece with the machining tool of a machine tool, and can simultaneously display a graph superimposed with reference data based on past data, etc.

1A shows a photograph of a tool holder unit having sensors that measure the temperature and acceleration of a tool being held in the rotating spindle of a machining center as a machine tool, and 1B shows an example photograph of an external terminal that receives and analyzes data from the tool holder unit in 1A. This shows an example of temperature data, acceleration data, and stress data measured by the unit of Figure 1 being displayed in a time series in a window on a display. 3 is a flow diagram showing a graph of the load meter value of the machine tool shown in FIG. 2 by the real-time data display means and the reference data display means of the machining state display device. 13 shows an image diagram illustrating a non-machining state (a) and a machining step 2 state (b) when #120 is a macro variable representing the machining state. (a) shows an example of a change in the macro variable value read during a processing process when #200 is the macro variable representing the processing state, and (b) shows a time series image of the load meter value during the processing process. The control flow of the reference data extraction means and the superposition means is illustrated in the circles 1 and 2 of FIG. The figure illustrates a method for acquiring reference data when the processing content is changed. (a) is an image diagram of re-acquiring reference data from real-time data of the entire processing process or part of the processing process. (b) shows an example of a display screen in reference data acquisition mode in which the check box in window 10 is turned on to acquire reference data. This shows a graph that displays two pieces of measurement data for the same tool and the same machining process without any time axis adjustment processing, and also a graph that displays the block number as one of the parameters of the NC program superimposed on the same time axis.

Figure 1(a) shows a photograph of a tool holder unit 1 (see Patent Documents 1 to 3) having sensors that measure the temperature and acceleration of a tool held by the rotating spindle 2 of a machining center as a machine tool. This tool holder unit 1 is held by the rotating spindle 2 at its upper part, like a normal tool holder, and holds a tool at its lower part, but unlike normal tool holders, it is formed as a unit with the function of being able to detect in real time the conditions in the vicinity of the tool during machining.

This unit measures the temperature and acceleration (vibration) of the tool during machining, and the load (stress (load meter value)) of the motor attached to the rotating spindle of the machining center, digitizes the data and transmits it to the outside, where it is received and analyzed by an external terminal (external computer 32). Figure 1(b) is an example photograph of an external terminal that receives and analyzes data from the tool holder unit 1 in Figure 1(a). The receiver 31 receives the digital data from the tool holder unit 1 and transmits it to the external computer 32. The external computer 32 receives the data transmitted from the receiver 31, processes (or calculates) it using dedicated software inside, and displays the data in a chronological graph in window 10 on the display.

Figure 2 shows an example of temperature data, acceleration data, and stress data measured by the unit in Figure 1 displayed in a time series in a window 10 on a display. Specifically, tag 11 displays a time chart of the machining process, tag 12 displays the acceleration value in the X direction from an acceleration sensor (not shown) mounted in the tool holder unit 1, tag 13 displays the acceleration value in the rotation direction from the acceleration sensor, tag 14 displays the temperature value from a thermocouple (not shown) disposed near the tip of the tool and the tool holder unit 1 that processes this data, and tag 15 displays the load value (load meter value) of the motor attached to the rotating spindle of the machining center in a time series graph. Figure 2 shows a real-time graph display (see real-time display graph 20) with the load meter value on the vertical axis and time (sec) on the horizontal axis.

Also, in FIG. 2, it can be seen that a real-time display graph 20 of the load meter value displayed in the display window 10 is superimposed on a reference data display graph 21 of past data, etc., which serves as a reference. By superimposing the real-time display graph 20 and the reference data display graph 21 in this way, the current tool status can be understood at a glance by comparing the tool being used for machining with reference data such as past data for the same tool and machining process.

Also, in Figure 2, in addition to the load meter value real-time display graph 20 and reference data display graph 21 displayed in the window 10 of the display, an upper threshold value of the load meter value is superimposed and displayed (see threshold display graph 22). If the load meter value exceeds the threshold during machining at the machining center, the tool number is displayed on the display (see reference number 23 in Figure 2), the color of the frame of window 10 is changed to display a warning, and an alarm sound is sounded to notify the operator. When the operator confirms the tool that has exceeded the threshold and clicks the alarm stop button 24, the color of the frame of window 10 is returned to normal, the alarm sound is turned off, and the warning display ends (details will be described later).

Next, we will explain the overlapping display of the real-time display graph 20 and the reference data display graph 21. Figure 3 shows a flow diagram for displaying the load meter value of the machine tool shown in Figure 2 with this machining state display device.

First, macro variables (custom macro variables) for sharing the machining state between the NC program of the machine tool and this machining state display device are set for each tool number (hereinafter also referred to as "tool number") designated for each tool (STEP 10). Variables used in the NC program are composed of three types: local variables, system variables, and macro variables (macro common variables), and a numerical value is substituted for "#3-digit number" in the NC program, so that they can be reused for various machining operations.
for example,
#100=10. …(1)
#101=20. + #100 … (2)
#100 = #100 + #101 ... (3)
in the case of,
In (1), the value 10. is assigned to variable #100, and in (2), the value 30., obtained by adding the value 20. and the value 10. in #100, is assigned to #101.

Among the variables used in such NC programs, macro variables are common variables that are part of the memory area inside the machine tool and can freely read and write actual values from within the machining program. These macro variables are #100 to #199 (variables that are cleared when the power is turned off) and #500 to #999 (variables that are not cleared when the power is turned off), and the variables that can be used vary depending on the machine tool. Macro variables can also be read from an external computer (see external computer 32 in Figure 1) that displays a graph in the display window of the actual machining status display device. Macro variables to be used to share the machining status between the CNC of the machine tool and the actual machining status display device running on the external computer 32 are determined, and a preset number (e.g., 1., 2., 3., ...) that represents the machining process is stored when machining is being performed on the machining program side, and a value is assigned so that 0. is stored otherwise.

For example, Figure 4 shows an image diagram showing (a) a non-machining state and (b) a state of machining process 2 when #120 is the macro variable representing the machining state. Note that in Figure 3, the numerical value 0 after the decimal point of the macro variable value is also displayed (for example, 0.0 indicates the macro variable value 0.), but in this specification, the decimal point of the macro variable value may not be displayed (for example, 0 indicates the macro variable value 0.).

Specifically, Table 1 below shows the NC program and macro variable values for a machining process consisting of three steps on a machining center, in which tool 1 (tool number 1) is used in both the first and third steps, and tool 2 (tool number 2) is used in the second step.

Refer again to the control flow diagram of the real-time display means and storage means in the present machining state display device shown in FIG. 3. In STEP 10, the macro variable value is set for each tool number specified for each tool, and when actual machining begins (STEP 12), the external computer 32 reads each tool number (tool number) and the macro variable value shared with the NC program (STEP 13). Next, the read macro variable value is judged (STEP 14 (processing of circle 1 will be described later)). If the macro variable value is 0, STEP 13 to STEP 14 are repeatedly executed, and when the macro variable value becomes other than 0, measurement of the load meter data of the machining center, acceleration data from the tool holder 1, and temperature data is started (STEP 16), and the measurement data is displayed in real time as a graph in the window 10 of the display of the external computer 32, etc. (STEP 18), and is sequentially saved in an external folder or memory (STEP 20). That is, the real-time data measured while executing control that triggers the start of measurement when the macro variable value changes from 0 to non-zero is displayed in a graph. This is a control function that eliminates the rise in the load meter value when the machining center's rotating spindle starts to rotate (and when it stops rotating (see below)).

Figure 5 (a) shows an example of the change in the macro variable value read during the machining process when #200 is the macro variable representing the machining state, and (b) shows a time series image of the load meter value during the machining process (similar to the acceleration value and temperature value). In the example of Figure 5 (a), it is composed of four machining processes, and as process 1, tool 1 (tool number 1) (not shown) is called, the spindle rotation is started, and the workpiece is approached (#200 = 0), (i) machining is performed by tool 1 (#200 = 1), (ii) retraction from the workpiece and stopping of the spindle rotation are performed (#200 = 0). Next, as process 2, (iii) tool 2 (tool number 2) is called, the spindle rotation is started, and the workpiece is approached (#200 = 0), after which (iv) machining is performed by tool 2 (#200 = 2), and (v) retraction from the workpiece and stopping of the spindle rotation are performed (#200 = 0).

Next, as step 3, (vi) tool 3 (tool number 3) is called, the spindle rotation starts, and the workpiece is approached (#200=0), after which (vii) machining is performed with tool 3 (#200=3), (ix) retraction from the workpiece, and the spindle rotation stops (#200=0). Furthermore, as step 4, (x) tool 1 (tool number 1) is called, the spindle rotation starts, and the workpiece is approached (#200=0), after which (xi) machining is performed with tool 1 (#200=4), (xii) retraction from the workpiece, and the spindle rotation stops (#200=0), and the machining process ends.

Figure 5(b) is an image of the time series of load meter values when, for example, process 2 is extracted from processes 1 to 4 shown in Figure 5(a), and shows the above (iii) to (v). As can be seen from this figure, the load meter value rises at the start of spindle rotation (iii) and at the stop of spindle rotation (v). Since the load meter value rises at this stage even though it is a non-machining stage, this machining state display device executes control not to measure at this stage. Specifically, this is STEPs 14 to 16 (and STEPs 22 to 24 described below) as previously described in Figure 3.

Returning to FIG. 3 again, as described above, when the macro variable value becomes 0, it is determined that the rotation of the spindle of the machining center has stopped, and the measurement is temporarily terminated (STEP 24). At this time, as shown in Table 1 and FIG. 5(a), a different tool may be replaced and a different process may be started, so it is determined whether the tool has been called (STEP 26). If the tool has not been called and all the machining processes have not been completed, the spindle has temporarily stopped for some reason, so it is confirmed that the macro variable is not 0 (STEPs 28 to 14), and the measurement continues as is (STEP 16). Also, if the tool has not been called and all the machining processes have been completed, reference data for the same tool and the same machining is created and saved in an external folder (STEP 30). At this time, if there is past data for the same tool (same tool number) and the same machining (same macro variable) in the external folder, this is updated while making corrections, etc.

Then, when the reference data is created, saved, and updated (STEP 30), the real-time graph display displayed in window 10 ends, and the display is reset (STEP 32). Also, when a tool is called in STEP 26, the reference data is created, saved, and updated (STEP 30) assuming that a machining process using a different tool (different tool number) is about to begin, the real-time graph display ends, and the display is reset (STEP 32), and STEPs 12 to 32 are repeated until all machining is completed. In this way, the graph displayed by the real-time display means is reset each time the tool is changed, and reference data corresponding to each tool and machining is created. This reference data is saved and updated simply by classifying it according to the same tool and the same machining, or it is saved and updated by classifying it according to machining defects such as tool damage and the number of machining operations for the same tool and the same machining (this will be described later).

Next, the control of superimposing the measurement graph displayed in real time in the window 10 by the real-time display means and the reference data by the reference data extraction means and the superimposing means will be described. FIG. 6 illustrates the control flow of the reference data extraction means and the superimposing means in the circles 1 and 2 in FIG. 3. When the macro variable value is set for each tool number, actual machining is started, and each tool number and macro variable value shared with the NC program are read (STEP 10 to STEP 13), it is determined whether or not to replace the tool with another tool and start a different process, that is, whether the tool has been called (STEP 50). If the tool has been called, the reference data for the same tool and the same machining is extracted from the reference data composed of past data, etc., that has already been saved and updated in STEP 50 (STEP 52). This reference data is composed of at least actual data from machining under the same conditions in the past, and is data that allows the user to clearly understand the current state of the tool by comparing it with the real-time data currently being machined. When the reference data mentioned in STEP 30 (see FIG. 3) is classified into the same tool and the same processing and the number of processing times (or processing defects), multiple reference data for the same tool and the same processing can be extracted. When the reference data is extracted and a graph of the reference data is already displayed in the window 10 (or when the reference data has already been loaded but the display is turned off and is not displayed in the window 10), the display of the displayed reference data (or the loaded reference data) is reset, and when no reference data has been loaded yet and no reference data is displayed in the window 10, the processing status display device loads the extracted reference data and displays the graph in the window (STEP 54 to STEP 58).

As described above in FIG. 3, acceleration data and temperature data are measured only when the macro variable value is other than 0, and the data is displayed in real time as a graph in window 10 and saved in an external folder, etc. (STEP 14 to STEP 24). When each tool is replaced, the graph display of the reference data displayed in window 10 is reset again (STEP 60), and then the reference data is created, saved, and updated (STEP 20).

Next, the creation, storage, and update of the reference data will be described.
3, the reference data is created, stored, and updated while acquiring and displaying in real time the machining data whose macro variable value is other than 0. However, in addition to the method of successively updating the reference data from the real-time data, there may be a method of fixing the first reference data (new reference data) for the same tool and the same machining process, or acquiring desired real-time data later and storing and updating the whole machining or a part of the machining.

Figure 7 illustrates a method for acquiring reference data when the machining contents are changed. (a) is an image of reacquiring reference data from real-time data of the entire machining process or part of the machining process, and (b) shows an example of a display screen in the reference data acquisition mode in which the check box in the window 10 is turned on to acquire reference data. The machining process illustrated here is one in which the same tools and each of the same machining processes as in Figure 5(a) are used as the entire machining process as shown in (a) (however, the first #200=0, #200=0 after #200=3, and #200=0 after #200=4 are omitted). Start the screen 100 in Figure 7(b) from a button in a predetermined position in the display 10 (omitted in Figure 3), turn on the check 101 of 'teaching Mode' on the screen 100, click 'Start' to enter the reference data acquisition mode, and click 'Stop' to end the reference data acquisition mode.

When this reference data acquisition mode is activated, real-time data in the machining state of #200 can be acquired and saved, except when the macro variable value is zero, as explained in FIG. 3. In step 1 shown in FIG. 7(a), the reference data acquisition mode is ON during all machining in the machining state of #200, and real-time data acquired in all steps is reacquired as reference data. If there is no reference data for all machining steps (step 1) in the machining state of #200 in the past, new reference data is created and saved as is, and if past reference data exists, it can be updated. Possible methods for updating include replacing with past reference data, averaging with past reference data, and correcting and setting the reference data using learning control. In addition, as described above, past data may be classified according to the number of machining times, and each past data may be updated.

As shown in step 2 of FIG. 7(a), real-time data is reacquired as reference data only for the machining process from the point when tool number 2 is replaced, which is part of the entire process of the machining state of #200, through machining by tool numbers 2 and 3, to the point when tool number 4 is replaced, and past reference data is reacquired for each past process of the machining state of #200 (step 2) or each process within step 2 (machining process #200=2 by tool number 2, machining process #200=3 by tool number 3).

In addition, in this machining state display device, in addition to displaying a graph of real-time data of tools, etc., and superimposing a graph of reference data for the same tool and the same machining in the window 10, a threshold value can be set for the reference data. In FIG. 2, a real-time display graph 20 of load meter value/time and a graph 21 of reference data are superimposed in the window 10, and a straight line 22 indicating the threshold value of the load meter value extending horizontally is displayed in the same window 10.

When the real-time display graph 21 during measurement exceeds the threshold value 22, the color of the tool number display portion 23 changes or an alarm sounds, etc., to allow the user to visually confirm. Also, when the threshold value 22 is exceeded, the tool number display portion 23 changes color to display a warning, and the warning display can be ended by clicking the tool number display portion 23.

The horizontal axis (time axis) of the graph in window 10 can be adjusted by stretching, adjusting the position, etc., using parameters (block number, coordinates, macro variables) of the NC program of the machine tool. Machining time in a machine tool varies even when the same tool and the same machining process are used. Fluctuations in machining time occur due to various factors, such as changes in the amount of compensation due to tool wear and feed overrides. However, when comparing data from the same tool and the same machining process (including comparing data from the same/similar tools or machine tools due to individual differences), if the machining time varies, comparing the real-time data with the reference data as is will result in fluctuations in the time axis between the processes from the start to the end of machining, making it difficult to make a detailed comparison.

Taking such cases into consideration, in this machining state display device, the horizontal axis of the graph is adjusted by expanding/contracting or aligning the time axis based on the parameters of the NC program in order to adjust the time axis to match the machining state. In Figure 8, two pieces of measurement data (load meter values) for the same tool and the same machining process are displayed as graphs in window 10 without time axis adjustment (see graphs (1) and (2)), and at the same time, the block number is superimposed on the same time axis (horizontal axis) as one of the parameters of the NC program and is displayed as a graph (see graph (3)). In addition, the left vertical axis shows the load meter values of graphs (1) and (2), and the right vertical axis shows the number of blocks in graph (3).

As shown by the arrow (a) at the bottom of the time axis (horizontal axis) in Figure 8, the waveform of graph (1) is a machining time of 65 (sec), as shown by the arrow (b) the waveform of graph (2) is a machining time of 55 (sec), and as shown by the arrow (c) the waveform of graph (3) is a machining time of 75 (sec), and the actual machining times are different even though the number of blocks in the NC program in graph (3) is the same. In this type of situation, the machining status display device adjusts the time axis (horizontal axis) as a whole to match the number of blocks in the NC program, and adjusts the length and width of graphs (1) and (2), and aligns graphs (1) and (2) so that the origin is set to number of blocks = 0.

1... tool holder unit 2... rotating spindle 10... window 11, 12, 13, 14, 15... tag 2... rotating spindle 20... real-time display graph 21... reference data display graph 22... threshold value display graph 23... tool number display portion 24... alarm stop button 31... receiver 32... external personal computer 100... screen 101... check

Claims (6)

A measuring means for measuring in real time a temperature and/or an acceleration of a machining tool at the tip of the machine tool during a machining process , and/or other physical quantity data including an output of a rotary spindle of the machine tool ;
a real-time data display means for displaying the physical quantity data measured in real time by the measuring means in a time-series real-time graph in a window capable of displaying a graph within a desired time range;
a reference data extraction means for extracting reference data of time series of physical quantity data for the same processing tool and processing process as those measured by the measurement means;
a reference data display means for displaying a reference graph in the window by superimposing the time-series reference data extracted by the reference data extraction means on the processing step being measured by the measurement means ,
The physical quantity data measured by the measuring means is stored or updated in the main body of the machine tool or in a storage means external to the machine tool,
The reference data extraction means extracts physical quantity data of a same processing tool and a same processing from the physical quantity data stored in the storage means as reference data;
the reference data extraction means extracts, when a machining tool is changed during operation of the machine tool, the changed machining tool and the same machining tool and physical quantity data of the machining as those executed by the changed machining tool as new reference data;
The reference data display means deletes the reference graph already displayed in the window when the machining tool is changed during operation of the machine tool, and displays the reference graph of the new reference data. The machining state display device according to claim 1, wherein the measurement means sets the measurement start condition to when machining of the workpiece with the tool actually starts during operation of the machine tool, and sets the measurement end condition to when machining of the workpiece with the tool actually stops. The machining state display device according to claim 2, wherein the start condition for measurement by the measuring means is when machining of the workpiece with the tool has actually started, and the determination is made when the value of a macro common variable that is used in an NC program that controls the operation of the machine tool and represents the machining state has changed to a value other than zero, and the end condition for measurement by the measuring means is when machining of the workpiece with the tool has not actually started, and the determination is made when the value of the macro common variable has changed to zero. 4. The machining state display device according to claim 3, wherein said reference data extracting means extracts reference data for macro common variables whose values are other than 0 for the same machining tool from the physical quantity data stored in said storage means. 2. The machining status display device according to claim 1, wherein the storage means stores physical quantity data measured by the measuring means in all machining steps of the machine tool or in each machining step among the all machining steps, and updates physical quantity data in the case where the physical quantity data in all machining steps or each machining step using the same machining tool has already been stored. The machining state display device according to any one of claims 1 to 5, wherein the reference data display means displays, in the window, a threshold value as the reference data that has been preset, or a threshold value as the reference data extracted by the reference data extraction means.