JP7026278B1 - Motion accuracy evaluation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motion accuracy evaluation device for extracting a region in which a motion error is within an allowable range as a usable region for a linear feed axis of a machine tool. SOLUTION: This is an evaluation device 1 for evaluating the motion accuracy of a motion mechanism unit having a motion mechanism unit having at least one linear feed axis. The evaluation device 1 analyzes the measurement data storage unit 2 that stores the measurement data of the motion error related to the linear feed axis and the measurement data stored in the measurement data storage unit 2, and the motion error of the linear feed axis is measured. It includes an evaluation unit 3 that extracts a region in the feed axis direction that falls within the allowable range as a usable region, and an output unit 6 that outputs information related to the usable region extracted by the evaluation unit 3 to the outside. [Selection diagram] Fig. 1

Description

The present invention relates to an evaluation device for evaluating the motion accuracy of a machine tool's motion mechanism, and more specifically, extracts a usable region from the motion regions of the corresponding feed shaft based on the measured motion accuracy. Regarding the evaluation device.

Conventionally, as an example of an apparatus for measuring the motion accuracy of a motion mechanism portion of a machine tool, a measuring apparatus disclosed in Japanese Patent Application Laid-Open No. 2019-206043 and a measuring method using the measuring apparatus are known. As shown in FIGS. 2 and 3, the measuring device 10 is composed of four laser length measuring instruments 11 and a mirror 15, and measures the motion accuracy of the machine tool 20 as shown in FIG. 2, for example.

The machine tool 20 of this example is composed of a bed 21 whose upper surface is a work mounting surface (so-called table), a gate-shaped frame 22, and a saddle 23. The frame 22 is arranged so that its horizontal portion is located above the bed 21, and its two vertical portions each engage with the side portion of the bed 21 so that the frame 22 can move in the Y-axis direction as a whole. It has become. Further, the saddle 23 engages with the horizontal portion of the frame 22 and is movable in the X-axis direction along the horizontal portion. In the saddle 23, the main shaft 24 is movable in the Z-axis direction. Moreover, it is rotatably held around an axis parallel to the Z axis. The X-axis, Y-axis, and Z-axis are reference axes that are orthogonal to each other, and each feed axis corresponding to the reference axis is an X-axis feed device (not shown), a Y-axis feed device (not shown), and a reference axis. It is composed of a Z-axis feed device (not shown).

Then, the four laser length measuring instruments 11 of the measuring device 10 are installed on the bed 21 at substantially equal intervals, and the mirror 15 is mounted on the spindle 24, and the X-axis feeding device of the machine tool 20 ( (Not shown), Y-axis feed device (not shown) and Z-axis feed device (not shown) measure the motion accuracy.

Specifically, the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) are positioned and controlled at regular intervals to control a three-dimensional space. The mirror 15 is positioned at each grid point whose inside is divided into a grid pattern at regular intervals, and at each grid point, the mirror 15 is irradiated with laser light from each laser length measuring device 11 and the reflected light is laser length measured. By receiving light from the device 11, the distance between the laser length measuring device 11 and the mirror 15 is measured by each laser length measuring device 11.

Then, based on the measurement data obtained as described above, the position of the mirror 15 at each of the lattice points in the three-dimensional space is calculated according to the principle of the three-sided survey method, and the calculated position data and the position data are calculated. The motion error is calculated by analyzing.

Japanese Unexamined Patent Publication No. 2019-206043

By the way, if the motion accuracy of the machine tool measured as described above is not within a predetermined allowable range, there is a high possibility that high-precision machining cannot be realized as it is. The X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) were repaired so as to restore the motion accuracy.

However, in order to repair the motion mechanism part, it is necessary to overhaul the machine tool as a whole, and for that purpose, there is a problem that the machine tool must be stopped for a long time.

On the other hand, for example, when the motion accuracy is deteriorated because a part of the ball screw constituting the feeding device is worn, the motion accuracy is good in the region other than the worn part of the ball screw. It is maintained. In this case, it is possible to realize high-precision machining in a region where good motion accuracy is maintained.

Therefore, if it is known that the motion accuracy is within the permissible range and the motion accuracy is not within the permissible range in the operation area of each feeder, the operator should perform processing using the motion accuracy within the permissible range. It is convenient because it can realize high-precision machining. If such measures can be taken, the machine tool can be operated for a long time without being stopped for overhaul, and the operating rate can be improved.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a motion accuracy evaluation device that extracts a region in which a motion error is within an allowable range as a usable region for a linear feed axis of a machine tool. And.

The present invention for solving the above problems
An evaluation device for evaluating the motion accuracy of the motion mechanism in a machine tool having a motion mechanism having at least one linear feed axis.
A measurement data storage unit that stores measurement data of motion error related to the linear feed axis, and a measurement data storage unit.
An evaluation unit that analyzes the measurement data stored in the measurement data storage unit and extracts a region in the feed axis direction in which the motion error of the linear feed axis falls within an allowable range as a usable region.
The present invention relates to a motion accuracy evaluation device including an output unit that outputs information related to a usable area extracted by the evaluation unit to the outside.

According to the motion accuracy evaluation device of this aspect (first aspect), the motion accuracy of the linear feed shaft constituting the motion mechanism portion of the machine tool is measured in advance by an appropriate measuring device, and the obtained measurement data is described above. It is stored in the measurement data storage unit.

Then, the evaluation unit analyzes the measurement data stored in the measurement data storage unit, and with respect to the linear feed axis, a region in the feed axis direction in which the motion error is within an allowable range is extracted as a usable region. , The information related to the extracted usable area is output to the outside by the output unit.

According to this motion accuracy evaluation device, the area where the motion error of the linear feed axis is within the allowable range is extracted as a usable area, and the information related to the extracted usable area is output to the outside by the output unit. Therefore, the operator can easily recognize from the output information where the motion accuracy is within the permissible range and where it is not within the permissible range in the operating region of the linear feed shaft.

Then, high-precision machining can be realized by performing machining using the operating region of the linear feed shaft where the motion accuracy is within the permissible range. Thus, by performing such processing, the machine tool can be operated for a long time without taking measures such as overhaul, and the operating rate can be improved. In the area not within the permissible range, it is possible to avoid the production of defective products by avoiding processing in this area.

Further, in the motion accuracy evaluation device of the first aspect, the motion accuracy evaluation device
NC program storage unit that stores NC programs,
The program stored in the NC program storage unit is analyzed to extract the operation area of the tool based on the reference position set for the work, and the extracted operation area of the tool and the extraction unit are extracted. Further, a work position setting unit that recognizes the reference position of the work in the feed axis direction in a state where the operation area and the usable area overlap by executing the process of superimposing the usable usable area. Prepare,
The output unit can further adopt an aspect (second aspect) configured to output the reference position of the work in the feed axis direction recognized by the work position setting unit to the outside.

In the motion accuracy evaluation device of the second aspect, the NC program to be executed is stored in the NC program storage unit in advance. Then, the work position setting unit first analyzes the NC program stored in the NC program storage unit, and extracts the operation area of the tool based on the reference position set for the work. Next, the work position setting unit executes a process of superimposing the operating area of the extracted tool and the usable area extracted by the evaluation unit, and the operating area and the usable area overlap each other. Recognize the reference position of the work in the feed axis direction. Then, the recognized reference position is output to the outside by the output unit.

Thus, according to this motion accuracy evaluation device, when the operator processes the workpiece using the NC program, the operator is within the operating region of the linear feed shaft based on the information output from the output unit. Since it is possible to recognize the reference position of the work in the feed axis direction, which can be machined using the place where the motion accuracy is within the permissible range, the reference position of the work was recognized when actually performing the machining. By arranging the workpiece so that it is in a position, it is possible to realize high-precision machining using a place where the motion accuracy is within the allowable range.

Further, the present invention is an evaluation device for evaluating the motion accuracy of the motion mechanism unit in a machine tool provided with the motion mechanism unit having at least one linear feed axis.
A measurement data storage unit that stores measurement data groups that have been repeatedly measured multiple times for motion errors related to the linear feed axis.
A plurality of measurement data groups stored in the measurement data storage unit are analyzed, and a region in the feed axis direction in which the motion error is within the allowable range is extracted as an allowable region for the linear feed axis, while the motion error is generated. The region in the feed axis direction that does not fall within the allowable range is extracted as the unacceptable region, and the region in the feed axis direction in which the repetition error between the measurement data groups falls within the predetermined reference range is extracted as the reproducible region. A region in the feed axis direction in which the repetition error does not fall within a predetermined reference range is extracted as a non-reproducible region, and a region that is a permissible region and a reproducible region in the feed axis direction is evaluated as a reproducible region and is permissible. An evaluation unit that evaluates a region that is an outer region and a reproducible region as a correctable region, and evaluates the non-reproducible region as an unusable region.
The present invention relates to a motion accuracy evaluation device including an output unit that outputs information evaluated by the evaluation unit to the outside.

According to the motion accuracy evaluation device of this aspect (third aspect), the motion accuracy of the linear feed shaft constituting the motion mechanism portion of the machine tool is repeatedly measured and measured in advance by an appropriate measuring device. A plurality of measurement data groups are stored in the measurement data storage unit.

Then, the evaluation unit analyzes a plurality of measurement data groups stored in the measurement data storage unit, and extracts a region in the feed axis direction in which the motion error is within the allowable range for the linear feed axis as an allowable region. On the other hand, the region in the feed axis direction where the motion error does not fall within the allowable range is extracted as an unacceptable region, and the region in the feed axis direction in which the repetition error between the measurement data groups falls within the predetermined reference range is reproduced. The region in the feed axis direction in which the repetition error does not fall within the predetermined reference range is extracted as a possible region, while the region in the feed axis direction is extracted as a non-reproducible region.

Next, the evaluation unit evaluates a region that is an allowable region and a reproducible region as a usable region in the feed axis direction, and evaluates a region that is an unacceptable region and a reproducible region as a correctable region. Then, the unreproducible area is evaluated as an unusable area. Then, the information evaluated by the evaluation unit is output from the output unit to the outside.

Thus, according to this motion accuracy evaluation device, the operating region of the linear feed shaft is divided into a usable region, a correctable region, and an unusable region, and the operator can use this information to determine the linear feed shaft. It is possible to easily recognize what kind of area each area of the operating area is. Then, by performing processing using the usable area in the operating area of the linear feed shaft, high-precision processing can be realized without taking any measures.

Further, in the area that can be corrected in the operation area of the linear feed axis, the operation of the linear feed axis is corrected by the correction amount calculated based on the measurement data, thereby realizing high-precision machining in the area as well. be able to. By performing such processing, the machine tool can be operated for a long time without taking measures such as overhaul, and the operating rate can be improved. As for the unusable area, it is possible to avoid the production of defective products by avoiding processing in this area.

In the motion accuracy evaluation device of the third aspect, the motion accuracy evaluation device
NC program storage unit that stores NC programs,
The NC program stored in the NC program storage unit is analyzed to extract the tool operation area based on the reference position set for the work, and the extracted tool operation area and the evaluation unit are used. By executing the process of superimposing the extracted usable area and correctable area, the work in the feed axis direction in a state where the operating area and at least one of the usable area and the correctable area overlap each other. Further equipped with a work position setting unit that recognizes the reference position,
The output unit can further adopt an aspect (fourth aspect) configured to output the reference position of the work recognized by the work position setting unit to the outside.

In the motion accuracy evaluation device of the fourth aspect, the NC program to be executed is stored in the NC program storage unit in advance. Then, the work position setting unit first analyzes the NC program stored in the NC program storage unit, and extracts the operation area of the tool based on the reference position set for the work. Next, the work position setting unit executes a process of superimposing the operating area of the extracted tool and the usable area and the correctable area extracted by the evaluation unit, and the operating area, the usable area, and the correctable area can be corrected. Recognize the reference position of the work in the feed axis direction in a state where at least one of the regions overlaps. Then, the recognized reference position is output to the outside by the output unit.

Thus, according to this motion accuracy evaluation device, when the operator processes the work using the NC program, the reference position of the work is recognized based on the information output from the output unit. By arranging the work so that it is in a position, the work can be machined with high accuracy. That is, if the work is arranged so that the operating area and the usable area of the tool overlap each other, high-precision machining can be realized without taking any measures. In addition, if the workpiece is arranged so that the operation area of the tool and the correctable area overlap, the operation of the linear feed axis is corrected by the correction amount calculated based on the measurement data, and high-precision machining is realized. can do.

According to the motion accuracy evaluation device according to the present invention, for the linear feed axis, the region where the motion error is within the allowable range is extracted as a usable region, and the information related to the extracted usable region is externally output by the output unit. Since it is output to, the operator can easily recognize from the output information where the motion accuracy is within the permissible range and where it is not within the permissible range in the operating region of the linear feed shaft.

Then, high-precision machining can be realized by performing machining using the operating region of the linear feed shaft where the motion accuracy is within the permissible range. Thus, by performing such processing, the machine tool can be operated for a long time without taking measures such as overhaul, and the operating rate can be improved. In the area not within the permissible range, it is possible to avoid the production of defective products by avoiding processing in this area.

It is a block diagram which showed the schematic structure of the motion accuracy evaluation apparatus and the like which concerns on one Embodiment of this invention. It is a perspective view which showed the measuring apparatus and the like which concerns on this embodiment. It is a front view which showed the measuring apparatus and the like which concerns on this embodiment. It is explanatory drawing which showed the error parameter which causes the motion error. It is a graph which shows the measured motion error. It is a graph which shows the measured motion error. It is a graph which shows the measured motion error. It is explanatory drawing for demonstrating the evaluation in the motion accuracy evaluation apparatus of this embodiment, and the correspondence based on this. It is explanatory drawing for demonstrating the evaluation in the motion accuracy evaluation apparatus of this embodiment, and the correspondence based on this.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the motion accuracy evaluation device 1 of this example includes a measurement data storage unit 2, an evaluation unit 3, an NC program storage unit 4, a work position setting unit 5, and an output unit 6. The motion accuracy evaluation device 1 is composed of a computer including a CPU, RAM, ROM, etc., and the functions of the evaluation unit 3, the work position setting unit 5, and the output unit 6 are realized by a computer program, and the processing described later is performed. To execute. Further, the measurement data storage unit 2 and the NC program storage unit 4 are appropriately composed of a storage medium such as a RAM.

The measurement data storage unit 2 stores in advance data related to the motion accuracy of the machine tool 20 measured by the measuring device 10. The measuring device 10 and the machine tool 20 have the same configurations as those of the above-mentioned conventional example. To reiterate, the outline will be described below.

The machine tool 20 is a so-called vertical machining center, and is configured to include a bed 21 whose upper surface is a work mounting surface, a gate-shaped frame 22, a saddle 23, and the like, and the frame 22 is the frame 22 thereof. The horizontal portion is arranged so as to be located above the bed 21, and the two vertical portions are engaged with the side portions of the bed 21 so as to be movable in the Y-axis direction as a whole.

Further, the saddle 23 engages with the horizontal portion of the frame 22 and can move in the X-axis direction along the horizontal portion, and the main shaft 24 of the saddle 23 can move in the Z-axis direction. Moreover, it is rotatably held around an axis parallel to the Z axis. Then, the work is placed on the bed 21, and the work is machined by moving the spindle 24 to the X-axis, the Y-axis, and the Z-axis with the tool mounted on the spindle 24.

The X-axis, Y-axis, and Z-axis are reference axes that are orthogonal to each other, and each linear feed axis corresponding to the reference axis is an X-axis feed device (not shown) and a Y-axis feed device (not shown). It is composed of a Z-axis feed device (not shown) and a Z-axis feed device (not shown).

The measuring device 10 is composed of four laser length measuring instruments 11, a mirror 15, and a calculation unit (not shown), and measures the motion accuracy of the machine tool 20. For example, the X-axis feed device (not shown) of the machine tool 20 with the four laser length measuring instruments 11 installed on the bed 21 at substantially equal intervals and the mirror 15 mounted on the spindle 24. ), Y-axis feed device (not shown) and Z-axis feed device (not shown) measure the motion accuracy.

More specifically, the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) are positioned and controlled at regular intervals in three dimensions. The mirror 15 is positioned at each grid point divided into a grid pattern at regular intervals in a space by a predetermined path (route), and at each grid point, each laser length measuring instrument 11 irradiates the mirror 15 with laser light. By receiving the reflected light with the laser length measuring device 11, the distance between the laser length measuring device 11 and the mirror 15 is measured by each laser length measuring device 11.

The laser length measuring device 11 is configured so that the laser interferometer 13 can be swiveled and moved around the center point of the reference ball 12 shown in FIG. 3, and the laser interferometer 13 is configured to move along with the movement of the mirror 15. Is configured to be able to automatically track the mirror 15 by turning and moving the mirror 15.

Then, the calculation unit (not shown) calculates the position of the mirror 15 at each of the grid points in the three-dimensional space according to the principle of the three-sided survey method based on the distance data obtained in this way. Based on the obtained position data, and by analyzing this position data, the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) For example, each motion error shown in FIG. 4 is calculated.

The definition of each motion error shown in FIG. 4 is as follows.
_EXX is a positioning error in the X-axis direction of the X-axis feeder.
_EYY is the positioning error of the Y-axis feeder in the Y-axis direction.
_EZZ is a positioning error in the Z-axis direction of the Z-axis feeder.
_EYX is the straightness error (Y-axis direction) in the X-axis-Y-axis plane of the X-axis feeder.
_EZX is the straightness error (Z-axis direction) in the X-axis-Z-axis plane of the X-axis feeder.
_EXY is the straightness error (in the X-axis direction) in the Y-axis-X-axis plane of the Y-axis feeder.
_EZY is the straightness error (Z-axis direction) in the Y-axis-Z-axis plane of the Y-axis feeder.
_EXZ is the straightness error (in the X-axis direction) in the Z-axis-X-axis plane of the Z-axis feeder.
_EYZ is the straightness error (Y-axis direction) in the Z-axis-Y-axis plane of the Z-axis feeder.
_EAX is the angle error around the X axis in the X axis feeder.
_EAY is the angle error around the X axis in the Y axis feeder.
_EAZ is the angle error around the X axis in the Z axis feeder.
_EBX is the angle error around the Y axis in the X axis feeder.
E _BY is the angle error around the Y axis in the Y axis feeder.
E _BZ is the angle error around the Y axis in the Z axis feeder.
E _CX is the angle error around the Z axis in the X axis feeder.
_ECY is the angle error around the Z axis in the Y axis feeder.
_ECZ is the angle error around the Z axis in the Z axis feeder.
EA _{(0Y) Z} is the right angle error between the Z-axis feeder and the ideal Y-axis.
_{EB (0Z) X} is the right angle error between the X-axis feeder and the ideal Z-axis.
EC _{(0X) Y} is a right angle error between the Y-axis feeder and the ideal X-axis.

An example of the motion error calculated as described above is shown in FIGS. 5, 6 and 7.

Further, in this example, the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) mirror the mirror in a predetermined forward path (forward route). 15 is moved and positioned at each of the lattice points, and after measuring the length with each laser length measuring device 11, the mirror 15 is moved by a path in the reverse direction (reverse route) to position the mirror 15 at each of the lattice points. However, the length is measured by each laser length measuring device 11. That is, the length is measured at each grid point by repeating the forward route and the reverse route twice.

Then, the calculation unit (not shown) calculates the position data of the forward route and the position data of the reverse route based on the distance data obtained by the repeated measurement, and the position data group related to each calculated route. The X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) are described above by analyzing each position data group. Calculate each motion error. Thus, for each of the calculated X-axis feed device (not shown), Y-axis feed device (not shown), and Z-axis feed device (not shown), each motion error for each route is related. The data is stored in the measurement data storage unit 2.

Further, the NC program storage unit 4 is a functional unit that stores NC (numerical control) programs, and NC programs used in the machine tool 20 are stored in advance.

The evaluation unit 3 refers to the data stored in the measurement data storage unit 2, and refers to the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown). For each of the above, the corresponding motion error is confirmed, and the region in the feed axis direction in which all the motion errors fall within the predetermined allowable range is extracted as the allowable region, and even one of the motion errors is within the allowable range. The area in the feed axis direction that does not fit is extracted as an unacceptable area. The allowable range is set for each motion error according to the required machining accuracy.

Further, the evaluation unit 3 calculates the repetition error by comparing the motion error in the forward route and the motion error in the reverse route, and sets the region in the feed axis direction in which the iteration error falls within a predetermined reference range as a reproducible region. Extraction is performed, and a region in the feed axis direction in which the repetition error does not fall within a predetermined reference range is extracted as a non-reproducible region. This reference range is also set for each motion error according to the required machining accuracy.

The evaluation unit 3 is an allowable region for each of the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) in the feed axis direction. The region that is a reproducible region is evaluated as a usable region, the region that is an unacceptable region and the reproducible region is evaluated as a correctable region, and the region that is an unacceptable region and the non-reproducible region is defined as an unusable region. evaluate. Then, the evaluation unit 3 outputs the information related to each evaluated area to the display device 7 via the output unit 3. The display device 7 is composed of a liquid crystal display or the like, and displays information related to each of the areas by numbers, figures, or the like.

The concept of the allowable area, the unacceptable area, the usable area, the reproducible area, the non-reproducible area, and the unusable area will be described with reference to FIG. In FIG. 8, the X-axis feed device (not shown) has an operating region of X ₀ to X _e in the X-axis direction, and the Y-axis feed device (not shown) has Y ₀ to Y in the Y-axis direction. It has an operating region of _e , and a Z-axis feed device (not shown) has an operating region of Z ₀ to Z _e in the Z-axis direction.

In FIG. 8, for example, for the Z-axis feed device (not shown), all motion errors fall within the _allowable range in the range of Z ₀ to Ze, which is the entire region in the Z-axis direction, and repeat errors occur. Assuming that it is within the reference range, for the Z-axis feed device (not shown), the range from Z ₀ to _Ze is extracted as an allowable region [a] and a reproducible region [ra], and this range is defined. Evaluated as usable area [ua].

Further, in the X-axis feed device (not shown), although all the motion errors are within the allowable range in the range of X ₀ to X ₁ and X ₂ to X _e in the X-axis direction, X ₁ to X. Assuming that at least one motion error is out of the allowable range in the range of ₂ , and that the repetition error in the range of X ₁ to X ₂ is within the reference range, the X-axis feed is concerned. For the device (not shown), the range of X ₀ to X ₁ and X ₂ to X _e is extracted as an allowable area [a] and a reproducible area [ra], and these ranges are usable areas [ua]. Is evaluated as. On the other hand, the range of X ₁ to X ₂ is an unacceptable region [na] and is extracted as a reproducible region [ra], and as a result, this range is evaluated as a correctable region [ca].

Further, in the Y-axis feed device (not shown), although all the motion errors are within the _allowable range in the range of Y ₀ to Y ₁ and Y ₂ to Ye in the Y-axis direction, Y ₁ to Y Assuming that at least one motion error in the range of ₂ is out of the allowable range and that the repetition error in the range of Y ₁ to Y ₂ is out of the reference range, the Y axis is concerned. For the feeder (not shown), the range of Y ₀ to Y ₁ and Y ₂ to Y _e is extracted as the allowable area [a] and the reproducible area [ra], and these ranges are the usable area [ua]. ] Is evaluated. On the other hand, the range of Y ₁ to Y ₂ is an unacceptable region [na] and is extracted as an unreproducible region [nra], and as a result, this range is evaluated as an unusable region [nua].

From the above, in the example shown in FIG. 8, on the upper surface of the bed 21, the region hatched by the alternate long and short dash line is the correctable region [ca], and the region hatched by the alternate long and short dash line is the unusable region [nua]. ], And the area to which nothing is attached is the usable area [ua].

Then, the above information is output from the evaluation unit 3 to the display device 7 via the output unit 6 and displayed.

The work position setting unit 5 analyzes the NC program stored in the NC program storage unit 4, extracts the operating area of the tool based on the reference position set for the work, and extracts the extracted tool. By executing the process of superimposing the operating area of No. 1 on the usable area [ua] and the correctable area [ca] extracted by the evaluation unit 3, the operating area, the usable area [ua], and the correctable area [ua] can be corrected. A process of recognizing the reference position of the work in the feed axis direction is performed in a state where at least one of the regions [ca] overlaps.

More specifically, for example, the work position setting unit 5 analyzes the NC program stored in the NC program storage unit 4, and based on the position command, feed rate command, etc., of the tool at the time of machining. In the operating area, the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) with reference to the reference position set for the work. Extract the operating area of the tool.

FIG. 9 shows a state in which the motion error of the machine tool 20 is the same as the state shown in FIG. 8, but for example, the work position setting unit 5 analyzes the NC program with respect to the work W. Tool operating area [ _mr ] in the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) based on the set reference position _Rp . To extract. It is assumed that the work W shown in FIG. 9 has a cylindrical shape, and the reference position (program origin) _Rp on the NC program is set at the center position of the upper surface of the work W. The reference position R _p in the work coordinate system parallel to the X-axis, Y-axis, and Z-axis, that is, the x-axis, y-axis, and z-axis coordinate system is x = 0, y = 0, z = 0. Further, in FIG. 9, the prismatic shape shown by the broken line indicates the operating region [ _mr ] of the tool.

Then, the work position setting unit 5 executes a process of superimposing the operating area [mr] of the extracted tool on the usable area [ _ua ] and the correctable area [ca] extracted by the evaluation unit 3. The X-axis feed device (not shown) and the Y-axis feed device (not shown) in a state where the operating area [ _mr ] and at least one of the usable area [ua] and the correctable area [ca] overlap each other. The reference position R _p (X _a , Y _a , Z _a ) of the work W in the machine coordinate system (X-axis, Y-axis, Z-axis coordinate system), that is, the Z-axis feed device (not shown). Perform the recognition process. In FIG. 9, the reference position _{R p} (X _a , Y _a , Z _a ) of the work W is set so that the operating area [mr] of the tool overlaps with the correctable area [ca]. Then, the work position setting unit 5 outputs the information regarding the recognized reference position R _p (X _a , Y _a , Z _a ) to the display device 7 via the output unit 6, and the output information is the display device. It is displayed in 7.

According to the motion accuracy evaluation device 1 of this example having the above configuration, the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis are based on the motion accuracy of the machine tool 20. For each operating area of the feeder (not shown), the allowable area [a], the unacceptable area [na], the reproducible area [ra], and the non-reproducible area [nra] recognized and evaluated by the evaluation unit 3. ], The information related to the usable area [ua], the correctable area [ca], and the unusable area [nua] is displayed on the display device 7 via the output unit 6, and the operator sees this information. Therefore, any of the operating areas of the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) can be used without taking any measures. Whether it is an area (usable area [ua]), which area is a usable area by correction (correctable area [ca]), or which area cannot be used (unusable area [nua]). ) Can be easily recognized.

Then, by obtaining such recognition, the operator can realize high-precision machining by installing the work W in the usable area (usable area [ua]) and executing the machining. Similarly, high-precision machining can be realized by installing the work W in a correctable region (correctable region [ca]) and executing machining, although it is possible or requires correction. Then, by taking such measures, the operator can avoid processing using the unusable area (unusable area [nua]), and can prevent defective products from being produced. ..

For example, in FIG. 8, the operator can avoid installing the work W in the unusable area [nua] on the bed 21 to perform processing as shown by the broken line, and the bed can be avoided as shown by the solid line. By installing the work W in the correctable area [ca] on the 21, high-precision machining can be executed. By performing such processing, the machine tool 20 can be operated for a long time without taking measures such as overhaul, and the operating rate can be improved.

In the example shown in FIG. 8, since most of the portion on the bed 21 is the correctable area [ca], an example is shown in which the work W is installed in this correctable area [ca] for processing. However, the present invention is not limited to this, and if the usable area [ua] has an area in which the work W can be installed, the work W is installed in the usable area [ua] for processing. It is preferable to do. Further, if neither the usable area [ua] nor the correctable area [ca] is large enough to install the work W and perform processing on the bed 21, in other words, When the unusable area [nua] occupies the majority, the operator can determine that the machine tool 20 needs to be overhauled.

Further, in the motion accuracy evaluation device 1 of this example, when the workpiece W is machined using the NC program, the tool operating area [mr] recognized by the NC program is the usable area [ _ua ] of the machine tool 20. ] And the reference position R _p (X _a , _Ya , Z _a ) of the work W so as to overlap with at least one of the correctable area [ca] is set by the work position setting unit 5, and the reference position R is set. Since _p (X _a , Y _a , Z _a ) is displayed on the display device 7, when machining the work W using the NC program, the operator is based on the information displayed on the display device 7. By aligning the work W so that the reference position R _p in the X-axis, Y-axis, and Z-axis coordinate system of the work W becomes the set position (X _a , Y _a , Z _a ), the work W can be moved. It can be processed with high precision.

That is, for example, if the work W is arranged so that the operating area [ _mr ] of the tool and the usable area [ua] overlap, high-precision machining can be realized without taking any measures. be able to. Further, if the work W is arranged so that the operating area [ _mr ] of the tool and the correctable area [ca] overlap, the correction amount calculated based on the measurement data is the X-axis feed device (not shown). ), Y-axis feed device (not shown) and Z-axis feed device (not shown), high-precision machining can be realized.

If the reference position R _p (X _a , Y _a , Z _a ) of the work W cannot be set by the work position setting unit 5, it means that the work W cannot be machined. Can avoid inadvertently performing processing using an unusable region (unusable region [nua]), and can prevent defective products from being produced. Further, the operator can consider measures for overhaul and the like of the machine tool 20.

Although the specific embodiments of the present invention have been described above, the modes that can be adopted by the present invention are not limited to those of the above examples.

For example, in the above example, the motion accuracy of the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) are measured by the forward route and the reverse route, respectively. However, the accuracy is not limited to such a mode, and the accuracy of repeating twice or more may be confirmed, or the measurement may be performed only once for the forward route. ..

Then, in the case of only one measurement, the evaluation unit 3 evaluates the allowable area [a] as the usable area [ua] and the unacceptable area [na] as the unusable area [nua]. Further, the work position estimation unit 5 executes a process of superimposing the operation area [ _mr ] of the tool recognized from the NC program and the usable area [ua] extracted by the evaluation unit 3 to operate. The above in the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown) in a state where the region [ _mr ] and the usable area [ua] overlap each other. The reference position R _p (X _a , Y _a , Z _a ) of the work W is recognized, and the information about the recognized reference position R _p (X _a , Y _a , Z _a ) is displayed via the output unit 6. Display on 7.

Further, in the above example, seven types of motion errors are measured for each of the X-axis feed device (not shown), the Y-axis feed device (not shown), and the Z-axis feed device (not shown). Based on this, each region is extracted and evaluated, but the present invention is not limited to this, and at least one type of motion error is measured for each feeder, and each region is extracted based on this. You may also evaluate it.

Further, in the above example, four laser length measuring instruments 11 are used as the measuring apparatus 10, but the present invention is not limited to this, and any measuring apparatus capable of measuring the motion accuracy of the machine tool may be used. Various measuring devices can be used.

Further, in the above example, the machine tool 20 as an evaluation target of motion accuracy is set as a vertical machining center, but the machine tool as an evaluation target is not limited to this, and a motion mechanism unit such as a horizontal machining center or a lathe is used. Various conventionally known machine tools having at least one linear feed axis can be applied.

Again, the description of the embodiments described above is exemplary in all respects and not restrictive. Modifications and changes can be made as appropriate for those skilled in the art. The scope of the invention is indicated by the claims, not by the embodiments described above. Further, the scope of the present invention includes modifications from the embodiments within the scope of the claims and within the scope of the claims.

1 Motion accuracy evaluation device 2 Measurement data storage unit 3 Evaluation unit 4 NC program storage unit 5 Work position setting unit 6 Output unit 7 Display device 10 Measuring device 11 Laser length measuring device 15 Mirror 20 Machine tool

Claims (4)

An evaluation device for evaluating the motion accuracy of the motion mechanism in a machine tool having a motion mechanism having at least one linear feed axis.
NC program storage unit that stores NC programs,
A measurement data storage unit that stores measurement data of motion error related to the linear feed axis, and a measurement data storage unit.
An evaluation unit that analyzes the measurement data stored in the measurement data storage unit and extracts a region in the feed axis direction in which the motion error of the linear feed axis falls within an allowable range as a usable region.
The NC program stored in the NC program storage unit is analyzed to extract the tool operation area based on the reference position set for the work, and the extracted tool operation area and the evaluation unit are used. It is provided with a work position setting unit that recognizes a reference position of the work in the feed axis direction in a state where the operating area and the usable area overlap by executing a process of superimposing the extracted usable area. An motion accuracy evaluation device characterized by being The motion accuracy evaluation device according to claim 1, further comprising an output unit that outputs a reference position of the work in the feed axis direction recognized by the work position setting unit to the outside. An evaluation device for evaluating the motion accuracy of the motion mechanism in a machine tool having a motion mechanism having at least one linear feed axis.
A measurement data storage unit that stores measurement data groups that have been repeatedly measured multiple times for motion errors related to the linear feed axis.
A plurality of measurement data groups stored in the measurement data storage unit are analyzed, and a region in the feed axis direction in which the motion error is within the allowable range is extracted as an allowable region for the linear feed axis, while the motion error is generated. The region in the feed axis direction that does not fall within the allowable range is extracted as an unacceptable region, and the region in the feed axis direction in which the repetition error between the measurement data groups falls within the predetermined reference range is extracted as a reproducible region. A region in the feed axis direction in which the repetition error does not fall within a predetermined reference range is extracted as a non-reproducible region, and a region that is a permissible region and a reproducible region in the feed axis direction is evaluated as a reproducible region and is permissible. An evaluation unit that evaluates a region that is an outer region and a reproducible region as a correctable region, and evaluates the non-reproducible region as an unusable region.
A motion accuracy evaluation device including an output unit that outputs information evaluated by the evaluation unit to the outside. NC program storage unit that stores NC programs,
The NC program stored in the NC program storage unit is analyzed to extract the tool operation area based on the reference position set for the work, and the extracted tool operation area and the evaluation unit are used. By executing the process of superimposing the extracted usable area and correctable area, the work in the feed axis direction in a state where the operating area and at least one of the usable area and the correctable area overlap each other. Equipped with a work position setting unit that recognizes the reference position
The motion accuracy evaluation device according to claim 3, wherein the output unit is further configured to output a reference position of the work recognized by the work position setting unit to the outside.

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