JPH0566820A - Numerical controller having measuring function - Google Patents

Abstract

PURPOSE:To attain the measurement of high accuracy in a short time by allowing the timing at which a touch sensor latches detecting position data of a feed shaft to correspond to a variation by which the touch sensor is turned on and off. CONSTITUTION:To a working program SA, in addition to each data of a measurement execution command and a measurement start point A, a virtual target point B, and a virtual object work surface C, to which of the time when a touch sensor 9 is changed from turn-off to turn-on or the time of the contrary the timing for latching detecting position data of a feed shaft as measurement data in advance is set is commanded. The measurement processing command part 16 in the latch timing control machine inputs an in-machine measurement command, data of points A-C and in-machine measurement relation data SQ being a latch timing command from a working program interpreting part 3, and outputs a latch timing command SM to a latch timing control part 13. On the other hand, based on the data of the points A-C of in-machine measurement relation data, a feed shaft control command SD is outputted to a shaft movement arithmetic part 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerical controller having an in-machine measuring function using a touch sensor.

[0002]

2. Description of the Related Art A touch sensor is provided on an axis moving part of a feed axis of a numerically controlled machine tool, and the touch sensor is brought into contact with an object to be measured by controlling the feed axis, and a signal from the touch sensor at that time is used. The in-machine measurement function of a numerically controlled machine tool that performs measurements by using the same has been put to practical use.

FIG. 7 is a block diagram showing the functions of a conventional numerical controller having a measuring function. The machining program SA input by the machining program input unit 1 is stored in the machining program storage unit 2. In the machining program SA, an in-machine measurement execution command for instructing to execute in-machine measurement, and a measurement serving as an axial movement start point of the touch sensor 9 when performing in-machine measurement as shown in FIG. A start point A, a virtual target point B that is a target point for the axial movement of the touch sensor 9, and each data of a virtual target work surface C that is a virtual position of the measurement target surface of the measurement target 10 are commanded. The machining program interpretation unit 3 interprets the meaning of the machining program SA stored in the machining program storage unit 2 while reading the machining program SA in blocks, and if the machining program SA includes an in-machine measurement command to perform in-machine measurement, an in-machine measurement command is issued. And the in-machine measurement related data SC which is the data of the points A to C is sent to the in-machine measurement processing command section 4. Based on the data of points A to C of the in-machine measurement related data SC, the in-machine measurement processing command unit 4
A feed axis control command SD is issued in order to axially move the touch sensor 9 from the measurement start point A to the virtual target point B. The axis movement calculator 5 calculates the axis movement according to the axis movement control command SD, and the feed axis controller 6 controls the motor 7 based on the calculation result SE, and the touch sensor 9 moves the axis. Touch sensor 9 equipped on the axis moving part of the feed axis
The current position is always detected by the position detector 8 and is always sent as detected position data SH.

The touch sensor 9 is in an OFF state when it is not in contact with the target work surface of the measurement object 10, and changes to an ON state at the moment of contact. Sensor signal detector 11
Detects a sensor signal SI indicating a change in the state of the touch sensor 9, and the sensor signal SI changes from OFF to ON.
When it changes to, the sensor latch signal SJ is sent out. In addition, the measured value data measuring unit 12 uses the sensor latch signal SJ.
The detected position data SH when the
Latched as the measurement position data SK of the target work surface of
The measurement position data SK is sent to the in-machine measurement processing command unit 4. The measurement position data SK is the measurement result, and indicates the measurement position of the target work surface of the measurement target 10. When the measurement position data SK is input, the in-machine measurement processing command unit 4 determines that the in-machine measurement has been completed, and the feed axis control command S
D is output to the axis movement calculation unit 5 to stop the movement of the feed axis, and the in-machine measurement completion signal SL is output to the machining program interpretation unit 3. Further, the in-machine measurement processing command unit 4 always inputs the detected position data SH from the position detection unit 8, and even when the detected position data SH becomes equal to the virtual target point B before inputting the measured position data SK. The feed axis control command SD is output to the axis movement calculation unit 5 to stop the movement of the feed axis, and the in-machine measurement completion signal SL is output to the machining program interpretation unit 3. In response to the completion signal SL, the machining program interpreting section 3 executes the next command of the machining program SA, for example, an axial movement command for separating the touch sensor 9 from the target work surface of the measuring object 10 as shown in FIG. ..

[0005]

Here, in the numerical control device having the above-mentioned measurement function, the same target work surface of the measurement target is measured twice, and the first measurement position data is used. Consider a method of obtaining highly accurate measurement data by performing the second measurement by performing the second measurement.

In a conventional numerical control device having a measuring function, as a method of measuring a target work surface of a measuring object twice, as shown in FIG. 6B, first, a measurement start point A ₁ and a virtual target point are measured. B ₁ , the _{first as} the virtual target work surface C
The first measurement is performed, and then the first measurement position data S
K ₁ is set to the virtual target point B ₂ of the _second measurement, the measurement start point A ₂ , the virtual target point B ₂ , and the virtual target work surface C are set, and the feed speed of the feed axis is set slower than that of the first measurement. Second
The method of performing the second measurement is generally performed. In this measuring method, the feed sensor is moved so that the touch sensor 9 moves along a path as shown in FIG.
The measurement is performed twice, and the touch sensor 9 is brought into contact with the target work surface of the measurement target 10 twice to perform the measurement. This is because the touch sensor 9 latches the detected position data SH as the measured position data SK of the target work surface of the measuring object 10 when the sensor signal SI changes from OFF to ON as described above.
The state that the sensor signal SI of changes from OFF to ON is 2
This is because it occurs once. However, if the touch sensor 9 moves along a path as shown in FIG. 6B and is brought into contact with the target work surface of the measurement object 10 twice to perform the measurement, a long time is required for the measurement. Since, during that time, machining cannot be performed, there was a practical problem as a measurement function.

That is, in the conventional measuring method using the touch sensor of the numerical controller having the measuring function, the touch sensor is brought into contact with the object to be measured, and the touch sensor is OF
The measurement is performed by utilizing the change from the F state to the ON state. However, if the measurement is performed only when the touch sensor changes from the OFF state to the ON state, in the measurement by the twice measurement of the touch sensor, it is necessary to bring the touch sensor into contact with the measurement object twice, and the in-machine measurement is performed. It took a long time for it.

The present invention has been made under the above circumstances, and an object of the present invention is, in a numerical controller having a measuring function, a timing at which a touch sensor latches feed shaft detected position data as measured position data. To
When the touch sensor status changes from OFF to ON,
Or by changing from ON to OFF,
An object of the present invention is to provide a numerical control device having a practical measurement function capable of performing highly accurate measurement in a short time.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a numerical controller having a measuring function, and the above object of the present invention is to provide a machining program command, an in-machine measurement execution command, a measurement start point A, and a virtual target point. B, in addition to each data of the virtual target work surface C, the timing of previously latching the detection position data of the feed axis as the measurement position data when the touch sensor changes from OFF to ON or from ON to OFF A latch timing command for instructing which of the two is to be issued is issued, and when the touch sensor state changes from OFF to ON or from ON to OFF according to the latch timing command, the touch sensor sends This is achieved by latching the detected position data of the axis as measured position data.

[0010]

According to the numerical controller having the measuring function of the present invention, when the state of the touch sensor changes from OFF to ON, or from ON to OFF, the touch sensor outputs the detection position data of the feed axis. Since it is latched as the measurement position data, accurate measurement can be performed in a short time. Since the measurement by the twice measurement of the touch sensor can be performed only by bringing the touch sensor into contact with the measurement object once, the measurement can be completed in a short time.

[0011]

1 is a block diagram showing the function of a numerical controller having a measuring function according to the present invention. The same parts as those of the conventional numerical control device having a measuring function shown in FIG. 7 are designated by the same reference numerals, and detailed description thereof will be omitted. In the numerical control device of the present invention, the latch timing control unit 13, the sensor signal conversion unit 14, the sensor signal ON / OFF detection unit 15, the latch timing control in-machine measurement processing command are added to the conventional numerical control device shown in FIG. The part 16 is newly provided. In the machining program SA, in addition to the in-machine measurement execution command and each data of the measurement start point A, the virtual target point B, and the virtual target work surface C, the timing of previously latching the detected position data of the feed axis as the measured position data, When the touch sensor 9 changes from OFF to ON, or from ON to OF
A latch timing command for instructing which one to change to F is issued in advance. The latch timing control in-machine measurement command unit 16 inputs the in-machine measurement command from the machining program interpreting unit 3, the data of the points A to C, and the in-machine measurement related data SQ which is the latch timing command, and the latch timing command SM as the latch timing. Output to the control unit 13. On the other hand, point A of the in-machine measurement related data SQ
Based on the data of C, the feed axis control command SD is output to the axis movement calculator 5. The sensor signal ON / OFF detection unit 15 is
The sensor signal SI representing the state of the touch sensor 9 is input, and when the sensor signal SI changes from OFF to ON, the sensor state change signal SO1 is transmitted, and the sensor signal S
When I changes from ON to OFF, the sensor state change signal SO2 is sent out.

Further, the latch timing controller 13 latches the detection position data of the feed axis as the measurement position data by the latch timing command SM when the touch sensor 9 changes from OFF to ON, and a timing signal. Timing signal SN when SN1 is when the touch sensor 9 changes from ON to OFF
2 is sent out. Then, in the sensor signal conversion unit 14, when the timing signal SN1 is input from the latch timing control unit 13, when the sensor state change signal SO1 is input, the sensor latch signal SP is output and the timing signal SN2 is input. If the sensor status change signal S
When O2 is input, the sensor latch signal SP is output.
The measurement value data measuring unit 12 latches the detection position data SH when the sensor latch signal SP is input as the measurement position data SK of the target work surface of the measurement object 10, and the latched measurement position data SK is controlled by the latch timing. It is sent to the in-machine measurement processing command unit 16. Latch timing control When the in-machine measurement processing command section 16 inputs the measurement position data SK, the in-machine measurement is completed and the feed axis control command SD
To the axis movement calculation unit 5 to stop the movement of the feed axis,
The in-machine measurement completion signal SL is output to the machining program interpretation unit 3. Further, the latch timing control in-machine measurement processing command unit 16 always inputs the detected position data SH from the position detection unit 8, and the detected position data SH becomes equal to the virtual target point B before the measured position data SK is input. Also at this time, the feed axis control command SD is output to the axis movement calculation unit 5 to stop the movement of the feed axis, and the in-machine measurement completion signal SL is output to the machining program interpretation unit 3.

FIG. 2B shows the relationship between the sensor signal SI and the sensor state change signal SO1, the sensor state change signal SO2, and the sensor latch signal SP when the timing signal SN1 or the timing signal SN2 is output. It is a time chart shown. Now, as shown in FIG. 2A, first, the feed sensor is moved so that the touch sensor 9 approaches the target work surface of the measurement object 10, and the measurement is performed. Consider a case in which the feed shaft is moved so as to move away from the target work surface of the measurement target object 10 after contacting the target work surface, and measurement is performed. In this case, the touch sensor 9 changes from OFF state → ON state → OFF state. When the timing signal SN1 is output, the sensor latch signal SP is output when the sensor state change signal SO1 is output.
Is output and the timing signal SN2 is output, the sensor latch signal SP is output when the sensor state change signal SO2 is output.

FIG. 3 shows the numerical control device having the measuring function according to the present invention described above. The same target work surface of the measuring object 10 is measured twice, and the second measurement position data is used. This is a method of obtaining highly accurate measurement data by performing the second measurement by performing the measurement. That is, in the numerical controller according to the present invention, the timing for latching the detected position data of the feed axis as the measured position data in the first measurement is commanded to be when the touch sensor 9 changes from OFF to ON. hand,
Measurement start point A ₁ , virtual target point B ₁ , virtual target work surface C
After the first measurement is performed, the first measurement position data SK ₁ is set to the measurement start point A ₂ of the second measurement, and then the detection position of the feed axis is measured in the second measurement. The timing for latching the data as the measurement position data is commanded to be when the touch sensor 9 changes from ON to OFF, and the measurement start point A ₂ , the virtual target point B ₂ , and the virtual target work surface C are set to the second position. The second measurement is performed, and the feed sensor is axially moved so that the touch sensor 9 moves along the path shown in FIG. 3, and the measurement is performed twice. In this case, the touch sensor 9 can perform the measurement only by contacting the target work surface of the measurement target object 10 once.

When the characteristics of the state change of the touch sensor 9 have hysteresis, the measurement value data correction unit 17 and the measurement correction data storage unit 18 are provided in the numerical controller shown in the block diagram of FIG. A numerical controller having a measuring function as shown in FIG. 4 is configured. Then, the touch sensor 9 is turned off on the same target work surface of the measurement target object 10.
From the ON position to the ON position and the difference between the measurement position data latched when the touch sensor 9 changes from the ON position to the OFF position in the measurement correction data storage unit 18 as the measurement direction correction value SR in advance. The measurement position data SK is stored, and the measurement position data SK is corrected by the measurement value data correction unit 17, so that the measurement position data without the influence of the hysteresis of the touch sensor 9 can be obtained.

FIG. 5 is a flow chart showing an operation example of the numerical controller having the measuring function of the present invention. First, the in-machine measurement execution command, the measurement start point A, the virtual target point B, each data of the virtual target work surface C, and the latch timing command are read from the machining program (step S1), the measurement start point A, the virtual target point B, The axis movement is started according to each data of the virtual target work surface C (step S2). And
The latch timing command indicates that the touch sensor 9 is in the OF state.
It is determined whether the change from F to ON or the change from ON to OFF occurs (step S3). When the latch timing command is when the state of the touch sensor 9 changes from OFF to ON, and when the state of the touch sensor 9 changes from OFF to ON during the axis movement, data measurement is performed (step S4). ,
Step S6), the state of the touch sensor 9 is changed from ON to OF
If it changes to F or does not change at all, the axis movement is continued to reach the virtual target point B (step S8). On the contrary, the latch timing command indicates that the touch sensor 9 is in the O state.
If it is when the state changes from N to OFF, or when the state of the touch sensor 9 changes from ON to OFF during the axis movement, data measurement is performed (steps S5 and S).
6) If the state of the touch sensor 9 changes from OFF to ON or does not change at all, the axis movement is continued to reach the virtual target point B (step S8). When the data measurement is completed, the axis movement is stopped (step S7), and the in-machine measurement is completed. If the virtual target point B is reached without data measurement, the axis movement stops at the virtual target point B (step S7), and all the operations are completed.

[0017]

As described above, according to the numerical controller having the measuring function of the present invention, the in-machine measurement by the touch sensor can be performed with high accuracy in a short time. That is, the measurement by the touch sensor twice can be performed only by bringing the sensor into contact with the measurement object once, so that the measurement can be completed in a short time.

[Brief description of drawings]

FIG. 1 is a block diagram showing functions of a numerically controlled lathe having a measuring function according to the present invention.

FIG. 2 is a diagram and a time chart for explaining a relationship between a timing signal, a sensor state change signal, and a sensor signal when actually measuring in a numerically controlled lathe having a measuring function according to the present invention.

FIG. 3 shows a numerical control lathe having a measurement function according to the present invention, in which the same target work surface of a measurement target is measured twice, and the second measurement is performed using the first measurement position data. It is a figure for demonstrating the method of obtaining highly accurate measurement data by the measurement of the 2nd time.

FIG. 4 is a block diagram showing a function of a numerical control device having a function of correcting a hysteresis of a state change of a touch sensor in a numerical control lathe having a measuring function according to the present invention.

FIG. 5 is a flowchart showing an operation example of a numerically controlled lathe having a measuring function according to the present invention.

FIG. 6 is a diagram for explaining a conventional method for in-machine measurement of a numerically controlled lathe having a measuring function.

FIG. 7 is a block diagram showing functions of a conventional numerically controlled lathe having a measuring function.

[Explanation of symbols]

 1 Machining program input section 2 Machining program storage section 3 Machining program interpretation section 4 In-machine measurement processing command section 5 Axis movement calculation section 6 Feed axis control section 7 Motor 8 Position detection section 9 Touch sensor 10 Target of measurement object 11 Sensor signal detection Part 12 Measurement data measurement part 13 Latch timing control part 14 Sensor signal conversion part 15 Sensor signal ON / OFF detection part 16 Latch timing control in-machine measurement processing part 17 Measurement value data correction part 18 Measurement value correction data storage part

Claims (2)

[Claims] 1. A numerical control device having an in-machine measurement function using a touch sensor, wherein the timing for latching the detection position data of the feed axis as the measurement position data is when the touch sensor changes from OFF to ON and when it is ON. A numerical control device having a measuring function characterized in that it is possible to instruct by a program which one of the states when the state changes from OFF to OFF. 2. At the same position, the difference between the measured position data latched when the touch sensor changes from OFF to ON and the measured position data latched when the touch sensor changes from ON to OFF is measured. The correction value is stored in advance as a direction correction value, and the measurement position correction value is corrected for the measurement position data obtained by the moving direction of the touch sensor during measurement.
Numerical control device having measurement function described in 1.