JP2003271212A - Inspection device of machine tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection device by which uniform results of inspection are obtained, regardless of operator's knowledge and experience. <P>SOLUTION: In a numerical control unit, servo data of a servomotor and machining dimension-measuring data of a workpiece acquired in a normal operation of a drive mechanism are registered in a RAM as master data by a step S101. Tolerance that is allowed for the master data is registered as parameters by a step S103. When inspecting the drive mechanism, the servo data or the like are acquired as sampling data by a step S111. The sampling data are compared with the master data to obtain difference of both data by a step S113. It is determined whether the difference is within limits of the registered tolerance, and if not, a warning message is displayed by a step S117. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine tool inspection apparatus for machining a workpiece using a drive mechanism driven by a servomotor.

[0002]

2. Description of the Related Art Generally, a machine tool controlled by a numerical control device processes a workpiece into a desired shape by a cutting tool or the like attached to a drive mechanism driven by a servo motor. In such a machine tool, the servo data of the servo motor and the machining dimension measurement data of the workpiece acquired during normal operation of the drive mechanism are used as master data in a data recording medium such as a floppy disk (registered trademark, the same applies hereinafter). Store and store it, and use it when inspecting the drive mechanism.

That is, at the time of periodic inspection of a machine tool, servo data and machining dimension measurement data are sampled, and master data read out from a data recording medium and the sampling data are graphically displayed and numerically compared. I was able to do it.

[0004]

However, even if the master data and sampling data are displayed as graphs and numerical values, the analysis results may be affected by the knowledge and experience of the operator who analyzes these data. . For this reason, since the criteria for judging whether the drive mechanism is normal or not is different for each worker from the sampling data at the time of inspection, there is a problem that the inspection result tends to vary.

Further, even if the judgment standard of the sampled data itself is clear, it is necessary to judge whether the drive mechanism is normal or not by taking into consideration the correlation with the past sampling data. In some cases. Therefore, in such a case, there is a problem that the inspection result is more likely to vary depending on the knowledge and experience of the operator who analyzes the sampling data.

Further, in any case, the above-mentioned analysis cannot be performed instantaneously, and a considerable time is required for the analysis and the quality judgment. Therefore, it reduces the number of inspection man-hours such as the periodic inspection and also prevents the machine stop time due to the inspection from being shortened, which causes a problem in improving the operating rate of the manufacturing line.

Further, when the master data is stored and stored in a removable data recording medium such as a floppy disk, the management of the data recording medium tends to be complicated, and depending on the management state, the data recording medium may be complicated. There is also a problem that there is a risk of losing.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a machine tool which can obtain a consistent inspection result regardless of the knowledge and experience of the operator. To provide an inspection device. Another object of the present invention is to provide a machine tool inspection device that can shorten the inspection time. Further, another object of the present invention is to provide a machine tool inspection device capable of facilitating the management of master data acquired during normal operation and preventing loss thereof.

[0009]

[Means for Solving the Problems and Actions and Effects of the Invention]
In order to achieve the above object, the machine tool inspection apparatus according to claim 1 is a machine tool inspection apparatus that processes a workpiece by using a drive mechanism driven by a servomotor, and when the drive mechanism is normal. Master data registration means for registering at least one of the acquired servo data of the servo motor and the machining dimension measurement data of the workpiece in the information storage device as master data, and a tolerance allowed for the master data. Tolerance registration means to register,
At the time of inspecting the drive mechanism, at least one of the servo data and the processing dimension measurement data is acquired as sampling data, sampling data acquisition means, sampling data acquired by the sampling data acquisition means, and the master data. Compare
The comparing means for obtaining the difference between the two and the difference are judged whether or not the difference is within the tolerance range registered in the tolerance registering means, and if not within the tolerance range, the drive mechanism is abnormal. The technical feature is that it includes an abnormality determination means for determining the above, and a predetermined operation means for performing a predetermined operation based on the abnormality determination by the abnormality determination means. Here, "servo data" refers to effective speed, effective current, position deviation, and the like, and "machining dimension measurement data" refers to sizing measurement values and the like.

According to the first aspect of the invention, the master data registration means registers at least one of the servo data of the servo motor acquired during normal operation of the drive mechanism and the machining dimension measurement data of the workpiece in the information storage device as master data. Then, the tolerance registration means registers the allowable tolerance for the master data. Then, at the time of inspecting the drive mechanism, the sampling data acquisition means acquires at least one of the servo data and the processing dimension measurement data as sampling data, and the comparison means compares the sampling data and the master data to obtain the difference between the two. The abnormality determination means determines whether the difference is within the tolerance range registered in the tolerance registration means. If the difference is not within the tolerance range, it is determined that the drive mechanism is abnormal. A predetermined operation is performed based on the abnormality determination. As a result, when inspecting the drive mechanism, the acquired sampling data is compared with the registered master data, and if the difference between the two is not within the tolerance range, the specified operation is performed, so the drive mechanism is automatically inspected. You can
Further, since the judgment work by the operator does not intervene, the inspection can be performed in a short time. Therefore, regardless of the knowledge and experience of the operator, there is an effect that an inspection result having no variation can be obtained and an inspection time can be shortened. Further, since the master data acquired during normal operation of the drive mechanism is registered in the information storage device, there is an effect that the master data acquired during normal operation can be easily managed and loss thereof can be prevented.

According to a second aspect of the present invention, there is provided a machine tool inspection apparatus according to the first aspect, in which the drive mechanism is inspected.
An inspection time registration means for registering a predetermined time and an inspection time detection means for detecting that a predetermined time registered in the inspection time registration means has arrived, and the inspection time detection means detects the predetermined time. Upon detecting the arrival, at least the sampling data is acquired by the sampling data acquisition unit, the difference is calculated by the comparison unit, the abnormality is determined by the abnormality determination unit, and the predetermined operation is performed by the predetermined operation unit. Is a technical feature.

According to the second aspect of the present invention, the inspection time registration means registers a predetermined time as the inspection of the drive mechanism, and the inspection time detection means detects that the predetermined time registered in the inspection time registration means has arrived. Upon detection, at least the sampling data is acquired by the sampling data acquisition unit, the difference is calculated by the comparison unit, the abnormality is determined by the abnormality determination unit, and the predetermined operation is performed by the predetermined operation unit.
Thus, when the predetermined time comes, the sampling data is acquired, the acquired sampling data is compared with the registered master data, and if the difference between the two is not within the tolerance, the predetermined operation is performed. The drive mechanism can be automatically inspected at the time. Therefore,
Since the worker does not need to manage the timing of periodic inspections,
In addition to the effect of obtaining a consistent inspection result, the effect of shortening the inspection time, the effect of facilitating the management of master data and the prevention of loss, when an operator forgets the time of periodic inspection, etc. However, there is an effect that regular inspections can be surely performed.

Furthermore, in the machine tool inspection apparatus according to a third aspect of the present invention, in the first aspect, when the abnormality determination unit determines the abnormality, the predetermined operation unit has an abnormality in the drive mechanism. Is a display control unit that causes the display device to display.

According to the third aspect of the invention, since the predetermined operation means is such display control means, when an abnormality is determined, the display device displays that an abnormality has occurred in the drive mechanism. Thus, the operator can be notified of the occurrence of an abnormality in the drive mechanism via the display device. Therefore,
In addition to the effect of obtaining a consistent inspection result, the effect of shortening the inspection time, the effect of facilitating the management of master data and the prevention of loss, it is possible for the operator to easily know the occurrence of an abnormality in the drive mechanism. is there.

Further, in the machine tool inspection apparatus according to claim 4, in claim 1, when the abnormality determination means determines that the abnormality has occurred, the predetermined operation means determines that an abnormality has occurred in the drive mechanism. It is technically characterized in that it is a display control means for displaying a numerical value or the content of an abnormality on a display device.

According to the fourth aspect of the invention, since the predetermined operation means is such display control means, when the abnormality is judged, the numerical value or the content of the abnormality of the drive mechanism is displayed on the display device. Let This allows the operator to be notified of the numerical value of the abnormality or the content of the abnormality via the display device. Therefore, in addition to the effect of obtaining a consistent inspection result, the effect of shortening the inspection time, and the effect of facilitating the management of master data and preventing loss,
There is an effect that the operator can easily know the numerical value of the abnormality of the drive mechanism and the content of the abnormality.

According to a fifth aspect of the present invention, in the machine tool inspection apparatus, the display control means according to the fourth aspect is provided with a correspondence table for identifying an abnormal portion based on the numerical value of the abnormality, and refers to the correspondence table. The technical feature is to display the position of the drive mechanism in which the abnormality has occurred on the display device.

According to the fifth aspect of the invention, the display control means causes the display device to display the position of the drive mechanism in which the abnormality has occurred, with reference to the correspondence table. This allows the operator to be notified of the abnormal position of the drive mechanism via the display device.
Therefore, in addition to the effect of obtaining a consistent inspection result, the effect of shortening the inspection time, the effect of facilitating the management of master data and the prevention of loss, the operator can easily know the abnormal portion of the drive mechanism. effective.

Further, in a machine tool inspection apparatus according to a sixth aspect of the present invention, in the first aspect, the predetermined operation means is a drive for stopping the drive of the drive mechanism when the abnormality determination means determines the abnormality. The technical feature is that it is a mechanism stopping means.

According to the sixth aspect of the invention, since the predetermined operation means is such a drive mechanism stopping means, when the abnormality is judged, the drive of the drive mechanism is stopped. As a result, it is possible to prevent malfunction of the drive device due to the abnormality. Therefore, in addition to the effect of obtaining a consistent inspection result, the effect of shortening the inspection time, the effect of facilitating the management of master data and the prevention of loss, avoiding unscheduled machining due to malfunction of the drive device, etc. There is an effect to obtain.

Furthermore, in the machine tool inspecting device of claim 7, in any one of claims 1 to 6, the comparing means obtains the results of frequency analysis of the sampling data and the master data, respectively. Based on this, the technical feature is to compare the two.

In the invention of claim 7, the comparison means compares the sampling data and the master data based on the results of frequency analysis of the sampling data and the master data, respectively. Therefore, the sampling data is analyzed from the viewpoint of frequency elements such as vibration. Can be compared. As a result, the state analysis by the frequency spectrum becomes possible, so that the drive mechanism can be further inspected in detail. Therefore, there is an effect that the inspection accuracy is improved and an inspection result having no variation is obtained.

Further, in the machine tool inspecting apparatus according to claim 8, in claim 7, the frequency analysis by the comparing means is technically performed within a range of a response frequency of a speed loop for controlling the drive mechanism. Characterize.

In the eighth aspect of the invention, the frequency analysis by the comparing means is performed within the range of the response frequency of the speed loop for controlling the drive mechanism. As a result, it is possible to perform the frequency analysis narrowed down within the necessary and sufficient frequency range, so that the analysis time can be shortened. Therefore, there is an effect that the inspection time can be further shortened.

A machine tool inspection apparatus according to a ninth aspect of the present invention is characterized in that, in any one of the first to eighth aspects, a data recording means for storing the sampling data in a data recording medium is provided. .

According to the invention of claim 9, the sampling data is stored in the data recording medium. With this, the past sampling data can be read from the data storage medium when necessary, so that the past sampling data can be utilized as the history information of the drive mechanism. Therefore, there is an effect that the inspection can be performed in consideration of the past state.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which a machine tool inspection apparatus of the present invention is applied to a machine tool numerical control apparatus will be described below with reference to the drawings. As shown in FIG. 1, the numerical controller 20 mainly includes an HMI unit 30 and a numerical controller 4.
0, a servo I / F 50, and the like. The numerical control device 20 has an original function of driving and controlling a workpiece driving motor Ma, a grindstone driving motor Mb, a spindle driving motor Mc, and the like, which serve as servo motors, and these servo motors will be described below. It also has the function of inspecting the drive mechanism driven by.

The HMI unit 30 has a function of interfacing with a worker, and outputs a start command or a stop command to the numerical control unit 40 based on the input information by the input operation of the worker, or a numerical value. It is used to input sampling data and the like sent from the control unit 40, and is used for the arithmetic unit 31, the RAM 33, the display unit 35, and the numerical control unit I / F3.
It is composed of 7 etc. In addition, human machine
The interface (Human Machine Interface) is named as follows.

The arithmetic unit 31 is a central processing unit or the like for controlling the numerical controller 20, and is a RAM via a system bus.
33, display unit 35, numerical control unit I / F 37, RO not shown
It is connected to M and an input / output interface (not shown).
A system program for controlling the arithmetic unit 31, an automatic inspection program described later, and the like are stored in a ROM (EPR) not shown.
OM, EEPROM, etc.).

The RAM 33 is a readable / writable volatile information storage device connected to the system bus, and for example, a DRAM (Dynamic RAM) is used. And
In the storage space, a work area required for the arithmetic unit 31 to perform arithmetic processing and the like, an area capable of storing the master data 33a and the parameters 33b, and the like are secured.

The master data 33a is obtained when the drive mechanism to be inspected is in normal condition, the workpiece drive motor Ma, the grindstone drive motor Mb, and the spindle drive motor M.
Servo data of a servo motor such as c and measurement data of machining dimensions of a workpiece. Here, "servo data" means
Refers to data related to motor servos such as effective speed, effective current, position deviation, etc.
Refers to data related to the dimensions of the workpiece, such as the measured values for a fixed size.

The parameter 33b is composed of a plurality of information used by the automatic inspection program described later. For example, the valid / invalid information of the function used for selecting the drive mechanism to be inspected, the time of the regular inspection ( For example,
(1 day, 1 week, 1 month, etc.), and various setting information such as tolerances set for each regular inspection.

The master data 33a and the parameters 33b are stored in the RAM 33 from an external data recording medium 60 such as a floppy disk or a memory card, a personal computer connected by a network, or the numerical controller 20 itself. It may be read from the hard disk device to the RAM 33. When read from the hard disk device (data recording means) included in the numerical control device 20 itself, it can be read when necessary, so that the master data 33a acquired at normal times can be easily managed and can be prevented from being lost. effective.

The display unit 35 is operable information as an operation panel of the numerical control unit 40, and F by an automatic inspection program described later.
It can output a frequency spectrum display after FT conversion, and is connected to the system bus via an input / output interface (not shown). For example, there is one that is configured by a CRT or a liquid crystal display and has a touch panel that constitutes an input device on the display surface. The numerical controller I / F 37 is an interface for enabling electrical connection with the numerical controller 40, and is connected to the arithmetic unit 31 via the system bus.

The numerical controller 40 operates the servo I / F 50 based on the start command output from the HMI unit 30.
Output a predetermined drive command to the servo I / O
The effective speed, the effective current, the position deviation, the sizing measurement value, and the like sent from F50 are sent to the HMI unit 30 as sampling data, and mainly include the calculation unit 41 and the HMI unit I.
/ F47 and the like.

The arithmetic unit 41 is a central arithmetic processing unit or the like for controlling the numerical control unit 40, like the arithmetic unit 31 of the HMI unit 30 described above, and is a RAM, R (not shown) via the system bus.
It is connected to the OM or the HMI unit I / F 47 and the like. A system program for controlling the arithmetic unit 41 is not shown in the ROM (EPROM, EEPROM, etc.).
Stored in advance.

The HMI unit I / F 47 is an interface for enabling electrical connection with the HMI unit 30, and is connected to the arithmetic unit 41 via the system bus. The servo I / F 50 uses the work driving motor M based on a predetermined driving command or the like output from the numerical controller 40.
a, a function for generating a predetermined command signal to be output to a servo motor such as a grindstone driving motor Mb and a spindle driving motor Mc, a workpiece driving motor Ma, a grindstone driving motor Mb,
It has a function of outputting the data received from each of the encoders Ea, Eb, Ec attached to the servomotor such as the spindle drive motor Mc to the numerical controller 40.

The workpiece drive motor Ma, the grindstone drive motor Mb, the spindle drive motor Mc, etc. connected to the servo I / F 50 are preceded by a control circuit and a servo amplifier, respectively, which are not shown. Is intervening. The control circuit includes a velocity loop and a current loop, and is configured to be able to output a pulse width modulation signal to the servo amplifier. Further, each servo motor has encoders Ea, Eb, Ec capable of speed detection and position detection.
Is attached, and the detected speed information and position information can be output to the numerical controller 40.

Numerical control device 20 configured in this way
The automatic inspection program is executed by the arithmetic unit 31 so that the automatic inspection process described below is executed. As shown in FIG. 2, in the automatic inspection process, after a predetermined initialization process, first, in step S101, a process of registering the master data 33a in the RAM 33 is performed. As described above, the master data 33a is read from the data recording medium 60, another personal computer or the like or the hard disk device or the like included in the numerical control device 20 itself.
It is read into AM33.

Next, in step S103, the parameter 3
A process of setting 3b and registering it in the RAM 33 is performed.
The parameter 33b includes valid / invalid information of the function used for selecting the drive mechanism driven by each servo motor to be inspected, the timing of the periodic inspection, the registration tolerance set for each periodic inspection, and the like. Various setting information and the like are included. Periodic inspections are, for example, daily, weekly,
Some are set relatively every month, and some are set absolutely by year / month / day / hour / minute / second. The registration tolerance indicates an allowable range in which it can be determined that the master data 33a is normal, and the registration tolerance is driven by a servomotor such as a workpiece driving motor Ma, a grindstone driving motor Mb, and a spindle driving motor Mc. It is set in advance for each drive mechanism to be used and for each periodic inspection.

The parameter 33b registered in this way
Is transferred to the numerical controller 40 in step S105, checked in step S107, and it is determined in step S109 whether an inspection is necessary. That is, of the parameters 33b registered in step S103, the parameter 33b is sent to the numerical controller 40 in step S105 in order to notify the numerical controller 40 of the valid / invalid information of the function of the drive mechanism to be inspected. , The contents of the parameter 33b in step S
It is checked by 107 to determine whether or not the inspection time has come, that is, whether or not the inspection is necessary, in step S109.
Judge by. In the numerical control unit 40, when the arithmetic unit 41 receives the valid / invalid information of the function of the drive mechanism through the numerical control unit I / F 37 and the HMI unit I / F 47, the information is registered in a RAM (not shown). To do.

When it is determined in step S109 that the inspection is necessary (Yes in S109), the following step S1
If the process shifts to step 11 and it is not possible to determine that the inspection is necessary (No in S109), the process returns to step S10.
Returning to step 7, the parameter 33b is checked. That is,
The process waits until the inspection time set in the parameter 33b arrives, and when the inspection time comes, the processing from step S111 is automatically executed.

Incidentally, such steps S107 and S1
09 without checking the parameter 33b,
By providing an entrance that enables processing from the next step S111, so-called manual operation can be performed, in which each processing after step S111 is executed by manual operation as needed for inspection.

In step S111, the sampling data is acquired and stored in the RAM 33. Specifically, the HMI unit 30 sends a data acquisition command to the numerical control unit 40 so as to acquire sampling data. Then, the numerical control unit 40 that receives it acquires the sampling data of the drive mechanism to be inspected based on the validity / invalidity information of the function of the drive mechanism that has been sent out beforehand, and acquires the obtained sampling data from the HMI unit. Send to 30. As a result, the HMI unit 30 can acquire the requested sampling data, and the acquired sampling data is temporarily stored in the RAM 33.

The acquired sampling data may be stored and saved in the data recording medium 60. Thereby, the past sampling data can be read from the data recording medium 60 when necessary, and the past sampling data can be utilized as the history information of the drive mechanism. Therefore, there is an effect that the inspection can be performed in consideration of the past state.

Step S111 is a sampling data analysis process by a subroutine, the details of which are shown in FIG. Therefore, from now on, it demonstrates with reference to FIG. As shown in FIG. 3, the sampling data analysis process starts with a process of performing a fast Fourier transform (hereinafter referred to as “FFT transform”) of the master data 33a in step S201. This FFT conversion is performed by the master data 33a.
Is performed in order to decompose the signal component contained in the signal for each frequency. For example, the master data 33a shown in FIG.
By performing an FFT conversion on an example (data waveform relating to rotation speed), a frequency spectrum (dashed line) shown in FIG. 5 (A) can be obtained.

In the following step S203, FFT conversion is performed on the acquired sampling data. F here
Similar to the FFT conversion of the master data 33a performed previously, the FT conversion is also performed to decompose the signal component included in the sampling data for each frequency. For example, Figure 4 (B)
By performing an FFT conversion on an example of the sampling data (data waveform relating to the rotation speed) shown in FIG. 5, a frequency spectrum (shown by a broken line) as shown in FIG. 5A can be obtained.

FFT by steps S201 and S203
When the conversion is completed, a process for obtaining the difference between the converted data is performed in step S205. That is, the difference between the master data 33a after FFT conversion and the sampling data after FFT conversion is calculated for each frequency.

Then, in step S207, it is determined whether or not the difference for each frequency obtained in step S205 is within the registered range. That is, the master data 33a
It is determined for each frequency whether the difference between the sampling data and the sampling data is within the range registered in the parameter 33b. Thus, if it is determined that the difference between the two is not within the range of the registration error at any frequency (Yes in S207), an abnormality has occurred in the drive mechanism that is the inspection target. Since the possibility is high, the process moves to step S209 to perform the abnormality determination process. On the other hand, at any frequency, if it cannot be determined that the difference between the two is not within the range of the registration error (No in S207), it is highly possible that the drive mechanism as the inspection target is normal. Then, the process proceeds to step S211, and the normality determination process is performed.

The abnormality determination processing in step S209 includes, for example, those shown in the following (1) to (3). In any case, after setting return information indicating an abnormality in a predetermined argument, a flag, etc., the process returns to the main routine shown in FIG. 2 and moves the process to step S115.

(1) The numerical value or the content of the abnormality that has occurred in the drive mechanism is stored in the RAM 33 for each frequency, or a process of editing is performed. Thereby, step S115
With this, the operator can be notified of the numerical value of the abnormality or the content of the abnormality via the display unit 35, so that the operator can easily know the numerical value of the abnormality of the drive mechanism and the content of the abnormality.

(2) Further, by pre-storing a frequency correspondence table (correspondence table) as shown in FIG. 5B in the RAM 33 or the like, the frequency correspondence table is stored for each abnormal frequency based on the frequency correspondence table. Perform processing to identify the location of the abnormality. Accordingly, in step S115, the position of the drive mechanism having the abnormality can be notified to the operator via the display unit 35, so that the operator can easily know the abnormal portion of the drive mechanism.

(3) Further, when the abnormality is determined in step S207, the process of outputting the stop command to the servomotor which gives the driving force to the abnormal drive mechanism and the abnormal drive mechanism are stopped. And a process of editing the message to the effect. As a result, the servo motor can be immediately stopped, and malfunction of the drive device due to the abnormality can be prevented, so that it is possible to avoid a situation where the workpiece is machined into an unexpected size or shape. . Further, in step S115, the operator can be notified of the message indicating that the abnormal drive mechanism has stopped via the display unit 35, so that the operator can easily know the stop of the drive mechanism.

The normality determining process in step S211 is as follows.
After setting return information indicating normality in a predetermined argument, flag, etc., the process returns to the main routine shown in FIG. 2, and the process proceeds to step S115.

The steps S201 and S20 described above are performed.
The FFT conversion by 3 and the processing of obtaining the difference between both data in step S205 are performed within the range of the response frequency of the speed loop that controls the drive mechanism, so that the frequency analysis is performed within the necessary and sufficient frequency range. You can As a result, the processing time can be shortened by the sampling data analysis processing.

Returning to the main routine shown in FIG. 2, in step S115, it is determined whether or not there is an abnormality from the result of the sampling data analysis processing. That is, since return information indicating normality or abnormality is set in a predetermined argument, flag, etc. in steps S209 and S211 shown in FIG. 3, in step S115, by referring to the predetermined argument, flag, etc. , Determine whether there is any abnormality. If there is an abnormality (Yes in S115),
A warning message or the like is displayed on the display unit 35 in step S117.
Is displayed, and if there is no abnormality (S115
No), the process returns to step S107 to check the parameters again, and waits for the arrival of the next inspection time.

In step S117, step S115
When it is determined that the abnormality has occurred, a process for displaying on the display unit 35 that an abnormality has occurred in the drive mechanism is performed. Since the display content follows the processing content performed in step S209, for example, (1) the numerical value of the abnormality or the content of the abnormality,
The display unit 35 displays (2) the position of the abnormal drive mechanism or (3) a message indicating that the abnormal drive mechanism has stopped. Then, when such display processing is completed, the process returns to step S107 to check the parameters again, and waits for the arrival of the next inspection time.

As described above, according to the numerical controller 20 of the present embodiment, when the drive mechanism is inspected, the acquired sampling data is compared with the registered master data 33a (S205, S207), If the difference between the two is not within the registered tolerance (Yes in S207)
s), abnormality determination processing is performed (S209). This allows
The drive mechanism can be automatically inspected, and the operator's own judgment work does not intervene, so the inspection can be performed in a short time. Therefore, regardless of the knowledge and experience of the operator, there is an effect that an inspection result having no variation can be obtained and an inspection time can be shortened. Further, the master data 33a acquired when the drive mechanism is normal
Is registered in the RAM 33, it has the effect of facilitating management of the master data 33a acquired during normal operation and preventing loss.

Further, the numerical controller 20 according to the present embodiment.
According to the above, at step S103 (inspection time registration means), a predetermined inspection time is registered as the inspection of the drive mechanism,
When the step S109 (inspection time detection means) detects that the registered predetermined inspection time has come (S1).
09: Yes), acquisition of sampling data by step S111 (sampling data acquisition means), calculation of difference by step S205 (comparison means), step S20
Abnormality determination by 7 (abnormality determination means) and step S
The abnormality determination processing (predetermined operation processing) by 209 and the display processing (predetermined operation processing) of a warning message and the like by step S117 are performed. Accordingly, when the predetermined inspection time comes (Yes in S109), sampling data is acquired (S111), the acquired sampling data is compared with the registered master data 33a (S205), and the difference between the two is the tolerance. If it is not within the range (Yes in S207),
Since the abnormality determination process (predetermined operation process) in step S209 and the warning message display process (predetermined operation process) in step S117 are performed, the drive mechanism can be automatically inspected at the predetermined inspection time. Therefore, since it is not necessary for the operator to manage the timing of the periodic inspection and the like, it is possible to obtain a consistent inspection result, to shorten the inspection time, and to facilitate the management of the master data 33a and prevent it from being lost. In addition, there is an effect that even if the operator forgets the time of the periodic inspection, the periodic inspection can be surely performed.

Further, the numerical controller 2 according to the present embodiment.
According to 0, if the difference between the two is not within the tolerance (S
Since the display process (predetermined operation process) of the warning message and the like in step S117 is performed in step S117, the operator can be notified of the abnormality occurrence of the drive mechanism via the display unit. Therefore, in addition to the effect of obtaining a uniform inspection result, the effect of shortening the inspection time, the effect of facilitating the management of the master data 33a and the prevention of loss thereof, the operator can easily know the occurrence of an abnormality in the drive mechanism. There is an effect to obtain.

Furthermore, according to the numerical controller 20 of the present embodiment, the sampling data analysis process enables
Sampling data (S203) and master data (S2
01) and (01) are compared based on the results of frequency analysis (S205), the sampling data can be analyzed and compared from the viewpoint of frequency elements such as vibration. As a result, as shown in FIG. 5 (A), since the state analysis based on the frequency spectrum is also possible, further detailed inspection of the drive mechanism can be performed. Therefore, there is an effect that the inspection accuracy is improved and an inspection result having no variation is obtained.

Further, the numerical controller 20 according to the present embodiment.
According to this, in the abnormality determination processing (S209), the position of the drive mechanism in which the abnormality has occurred is displayed on the display unit 35 with reference to the frequency correspondence table as shown in FIG. 5B (S117).

For example, the grindstone shaft rotates at a rate of several thousand times per minute, and when it is converted into a frequency, it becomes 100.
Corresponds to Hz order. Here, if the axis of the grindstone shaft is eccentric, the frequency tends to increase. For example, if the normal frequency of this grindstone shaft is 150 Hz, the frequency at eccentricity exceeds the value of 150 Hz by some percentage. become. Therefore, when data having an error around 150 Hz is obtained from the analysis of the frequency spectrum, it is possible to determine whether or not the grindstone shaft is abnormal by comparing it with the tolerance. In other words, if the normal frequency of 150Hz is f1,
It can be seen from the frequency correspondence table of FIG. 5 (B) that the frequency components appearing in the frequencies before and after this indicate that the wheel axis is abnormal. Similarly, if the vibration frequency peculiar to the grinding head is f2, the vibration frequency peculiar to the table is f3, and the vibration frequency peculiar to the spindle headstock is f4, each abnormal point can be identified from the frequency correspondence table of FIG. 5 (B). it can.

As a result, the operator can be informed of the position of the drive mechanism having an abnormality through the display section 35. Therefore, in addition to the effect of obtaining a consistent inspection result, the effect of shortening the inspection time, the effect of facilitating the management of master data and the prevention of loss, the operator can easily know the abnormal portion of the drive mechanism. effective.

In FIG. 5A, the sum of the registration tolerance and the master data 33a is represented by a solid line, the sampling data is represented by a broken line, and the master data is represented by a one-dot chain line. In this way, by displaying on the display unit 35 a display screen in which the frequency components such as the frequency of the driving mechanism driven by each servo motor are represented by the frequency spectrum, the knowledge and experience of the operator are not affected. It is also possible to check the abnormality of the drive mechanism at a glance.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a numerical control device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a flow of automatic inspection processing by the numerical control device according to the present embodiment.

FIG. 3 is a flowchart showing a flow of sampling data analysis processing shown in FIG.

FIG. 4 is an explanatory view showing an example of a data waveform relating to a rotation speed of a servo motor, FIG. 4 (A) shows the one based on master data, and FIG. 4 (B) shows the one based on sampling data.

5A is an explanatory diagram showing an example of a frequency spectrum of data relating to the rotation speed of the servo motor, and FIG.
(B) is an explanatory view showing an example of a frequency correspondence table.

[Explanation of symbols]

20 Numerical Control Device (Machine Tool Inspection Device) 30 HMI Unit 31 Computing Unit 33 RAM (Information Storage Device) 33a Master Data 33b Parameter (Tolerance) 35 Display Unit (Display Device) 40 Numerical Control Unit 60 Data Recording Medium (Data Recording) Means) Ma work drive motor (servo motor) Mb grindstone drive motor (servo motor) Mc spindle drive motor (servo motor) S101 (master data registration means), S103 (tolerance registration means, inspection time registration means), S107 (inspection timing detection means), S109 (inspection timing detection means), S111 (sampling data acquisition means), S115 (abnormality determination means), S117 (predetermined operation means, display control means), S2
05 (comparing means), S207 (abnormality determining means), S20
9 (Abnormality determination means)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Abe Go             1-1 Asahi-cho, Kariya city, Aichi             Machine Co., Ltd. F term (reference) 3C029 DD00                 5H269 AB01 BB12 EE01 EE11 GG01                       MM04 NN05 NN08 PP02 PP03                       QC06 QD03 QE37

Claims (9)

[Claims] 1. An inspection apparatus for a machine tool, which processes a workpiece by using a drive mechanism driven by a servo motor, comprising: servo data of the servo motor and the machining obtained when the drive mechanism is normal. Master data registration means for registering at least one of the processing dimension measurement data of an object as master data in an information storage device, a tolerance registration means for registering a tolerance allowed for the master data, and an inspection of the drive mechanism. In, at least one of the servo data and the machining dimension measurement data is acquired as sampling data, and the sampling data acquired by the sampling data acquisition means is compared with the master data, and the difference between the two is obtained. Comparing means for obtaining the difference, and the difference is the tolerance registration means Based on the abnormality determination means for determining whether or not the drive mechanism is abnormal if it is within the registered tolerance range and if it is not within the tolerance range, based on the abnormality determination by the abnormality determination means. A machine tool inspection apparatus, comprising: predetermined operation means for performing a predetermined operation; 2. An inspection time registration means for registering a predetermined time when inspecting the drive mechanism, and an inspection time detection means for detecting that a predetermined time registered in the inspection time registration means has arrived. When the inspection time detection means detects that the predetermined time has arrived, at least the sampling data is acquired by the sampling data acquisition means, the difference is calculated by the comparison means, and the abnormality is detected by the abnormality determination means. The machine tool inspection apparatus according to claim 1, wherein the determination and the predetermined operation are performed by the predetermined operation means. 3. The predetermined operation means is a display control means for displaying on a display device that an abnormality has occurred in the drive mechanism when the abnormality determination means determines the abnormality. The machine tool inspection apparatus according to claim 1. 4. The predetermined operation means is a display control means for displaying, on the display device, the numerical value of the abnormality or the content of the abnormality that has occurred in the drive mechanism when the abnormality determination means determines the abnormality. The machine tool inspection apparatus according to claim 1, wherein: 5. The display control means includes a correspondence table for identifying an abnormal place based on the numerical value of the abnormality, and the position of the drive mechanism in which the abnormality has occurred is displayed on the display device with reference to the correspondence table. The machine tool inspection device according to claim 4, wherein 6. The work according to claim 1, wherein the predetermined operation means is drive mechanism stopping means for stopping the drive of the drive mechanism when the abnormality determination means determines the abnormality. Machine inspection equipment. 7. The comparison unit compares the sampling data and the master data with each other on the basis of the results of frequency analysis of the sampling data and the master data, respectively. Machine tool inspection device. 8. The frequency analysis by the comparing means comprises:
The machine tool inspection apparatus according to claim 7, wherein the inspection is performed within a range of a response frequency of a speed loop that controls the drive mechanism. 9. The machine tool inspection device according to claim 1, further comprising a data recording unit that stores the sampling data in a data recording medium.