JP2023084017A - Tool imaging device - Google Patents

Abstract

To provide a tool imaging device that can set an interval of imaging positions with high accuracy, in imaging the whole of a processing surface of a tool.SOLUTION: A tool imaging device 20 repeatedly executes imaging of a processing surface 40 of a wire 11, in a state where the wire 11 which is a tool of a wire saw 10 is moving. An electronic control device 30 detects a movement speed in a moving direction of the processing surface 40, and sets a target execution period for an execution period during which imaging with a camera 21 is executed on the basis of the movement speed. The electronic control device 30 executes the imaging with the camera 21 on the basis of the target execution period.SELECTED DRAWING: Figure 1

Description

The present invention relates to a tool imaging device for imaging a machined surface of a tool used for machining by a machining apparatus.

A wide variety of tools are used in processing apparatuses, such as rotating grindstones in grinding apparatuses and diamond wires in wire saws. During machining by a machining apparatus, the finish quality of the machined surface of the workpiece depends on the condition of the machined surface of the tool.

Conventionally, there has been proposed a device for determining the state of a machined surface of a tool (for example, Patent Document 1). In the apparatus described in Patent Document 1, the machined surface of the tool is imaged using a metallurgical microscope equipped with a camera. Then, the state of the machined surface is determined based on the imaging data.

JP-A-2004-45078

Among the tools used in the processing apparatus, the grindstone and the diamond wire have an elongated working surface in the moving direction (specifically, the rotation direction of the grindstone or the axial direction of the diamond wire). In order to determine the state of such a long machined surface, when acquiring a captured image of the entire machined surface, it is conceivable to image the machined surface with a camera as follows. That is, under the condition in which the processing device is operated to move the processing surface, the camera repeatedly captures images of the processing surface in accordance with a predetermined imaging pattern. Accordingly, it is possible to obtain captured images of the entire processed surface by acquiring captured images of the processed surface at intervals assumed in advance.

Since the machining surface of the tool moves at high speed during the operation of the machining apparatus, the timing of actually acquiring the captured image when imaging the machining surface is susceptible to variations in the movement speed of the machining surface. Therefore, even if the camera simply captures images of the machined surface using a predetermined image capturing pattern, it is difficult to obtain captured images with high accuracy at the intervals between the movement positions assumed in advance.

A tool imaging device for solving the above problems is applied to a tool that is used for processing by a processing device and has an elongated shape with a processing surface extending in a moving direction of the processing surface, In a tool imaging device that repeatedly captures images of a machined surface while the machined surface is moving, a speed detection unit that detects a moving speed of the machined surface in the moving direction, and the It has a target setting unit that sets a target value for execution timing for performing the imaging based on the movement speed, and an imaging execution unit that performs the imaging based on the target value.

According to the above configuration, it is possible to set the timing (specifically, the target value) for executing the imaging of the machined surface after that, depending on the actual moving speed of the machined surface of the tool at that time. Therefore, when repeatedly imaging the processed surface while the processed surface is moving, it is possible to determine the interval between the imaging portions that are actually imaged with high accuracy. As a result, it is possible to obtain a captured image of the entire machining surface of the tool with high accuracy in accordance with a presupposed mode.

ADVANTAGE OF THE INVENTION According to this invention, when imaging the whole machining surface of a tool, the space|interval of an imaging position can be determined with high precision.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of the tool imaging device of 1st Embodiment, and its periphery. It is a top view which shows the roller and wire for processing of a wire saw to which the tool imaging device is applied. 4 is a time chart showing an example of a wire movement mode during operation of the wire saw. It is a schematic diagram which shows the arrangement|positioning aspect of a 1st illumination part and a 2nd illumination part. FIG. 4 is a plan view of the wire; FIG. 4 is an explanatory diagram for explaining a learning mode of a learning device; FIG. 4 is an explanatory diagram for explaining generation errors output from a learning device; (a) to (e) are side views showing examples of wire states. 4 is a flow chart showing an execution procedure of camera control processing; 4 is a flowchart showing an execution procedure of operation control processing; 10 is a flow chart showing the execution procedure of camera control processing according to the second embodiment; It is a schematic diagram which shows a 1st captured image and a 2nd captured image. (a) to (c) are explanatory diagrams for explaining the relationship between the wire and the imaging position of the camera in the third embodiment. FIG. 11 is a flow chart showing the execution procedure of camera control processing according to the third embodiment; FIG. It is a schematic block diagram of the tool imaging device of other embodiment. (a) to (c) are side views showing an example of how abrasive grains are dispersed on the working surface of the wire. It is a schematic block diagram of the wire electric discharge machining apparatus with which the tool imaging device of other embodiment is applied. FIG. 11 is a schematic configuration diagram of a grinding apparatus to which a tool imaging device of another embodiment is applied;

(First embodiment)
A first embodiment of the tool imaging device will be described below with reference to FIGS. 1 to 10. FIG.
As shown in FIGS. 1 and 2, the tool imaging device 20 of the present embodiment is applied to a diamond wire (hereinafter referred to as wire 11) used for machining by the wire saw 10. As shown in FIG.

<Wire saw 10>
The wire saw 10 as a processing device will be described below.
A wire saw 10 has a pair of reels 12 and 13 around which the wire 11 is wound. These reels 12 and 13 are rotatably supported about axes extending in parallel. The wire saw 10 also has a pair of processing rollers 14 and 15 . The processing rollers 14 and 15 are rotatably supported about axes extending in parallel. A large number of annular grooves 141 and 151 (FIG. 2) are formed at a constant pitch on the outer peripheral surfaces of the processing rollers 14 and 15, respectively. In the wire saw 10, a single wire 11 is wound in a suspended state between annular grooves 141 and 151 of processing rollers 14 and 15. As shown in FIG.

A rotation drive unit 16 is connected to the reel 12 . The rotation drive unit 16 includes a servomotor 16M that rotates the reel 12, an encoder 16E that detects the rotation phase and rotation speed of the servomotor 16M, and a motor control device 16C that controls the operation of the servomotor 16M. have. A rotation drive unit 17 is connected to the reel 13 . The rotary drive unit 17 includes a servomotor 17M that rotates the reel 13, an encoder 17E that detects the rotation phase and rotation speed of the servomotor 17M, and a motor control device 17C that controls the operation of the servomotor 17M. have.

When the work W1 is machined by the wire saw 10, the reels 12 and 13 are rotationally driven through operation control of the rotational drive units 16 and 17. As shown in FIG. As a result, the wire 11 wound around the reels 12 and 13 is guided onto the processing rollers 14 and 15 and travels around between the processing rollers 14 and 15 .

The wire saw 10 has a support portion 18 that detachably supports the work W1. The support portion 18 is arranged above the wire 11 between the working rollers 14 and 15 . The support portion 18 has a structure capable of moving in a direction toward the wire 11 (downward in FIG. 1) and a direction away from the wire 11 (upward in FIG. 1).

The wire saw 10 has an electronic controller 30 . Rotation drive units 16 and 17 are connected to the electronic control unit 30 . The electronic control unit 30 has a CPU 31, a ROM 32, a RAM 33, and a storage section 34 for storing various programs and data. The storage unit 34 is composed of a non-volatile memory such as a hard disk drive or a solid state drive that can be written and read at any time. The electronic control unit 30 is configured to execute various arithmetic processes based on various programs and data. The electronic control unit 30 controls the operation of the rotary drive units 16 and 17 based on the calculation results.

In this embodiment, the movement pattern of the wire 11 is predetermined. Operation control of the rotary drive units 16 and 17 (specifically, the servo motors 16M and 17M) is executed in a manner that realizes this movement pattern.

FIG. 3 shows an example of how the wire 11 moves when the wire saw 10 is in operation.
As shown in FIG. 3, the wire saw 10 operates (so-called traverse operation) so as to alternately repeat [forward movement] (time T11 to T16) and [backward movement] (time T16 to T21) described below. It's like

[Forward Movement] A wire 11 of a predetermined length LG is let out from the reel 12 and wound on the reel 13 .
[Return] A wire 11 of a predetermined length LB (where LG>LB) is wound on a reel 12 and unwound from a reel 13 .

In the [forward movement] period, the wire 11 is first accelerated in the direction in which the wire 11 is let out (forward direction) during the acceleration period (time T11 to T13). Then, when the wire 11 reaches a predetermined speed, the moving speed of the wire 11 is kept constant at the predetermined speed during the subsequent constant speed period (time T13 to T14). During the subsequent deceleration period (time T14 to T16), the wire 11 is decelerated and temporarily stopped.

In the [return] period, the wire 11 is first accelerated in the winding direction (reverse direction) during the acceleration period (time T16 to T18). Then, when the wire 11 reaches the predetermined speed, the moving speed of the wire 11 is kept constant at the predetermined speed during the subsequent constant speed period (time T18 to T19). During the subsequent deceleration period (time T19 to T21), the wire 11 is decelerated and temporarily stopped.

In this embodiment, an execution program that realizes the operation of the wire saw 10 is determined and stored in advance in the storage unit 34 of the electronic control unit 30 .
As shown in FIG. 1, machining of a work W1 by the wire saw 10 is performed as follows. First, the wire 11 is made to travel around between the processing rollers 14 and 15 through operation control of the rotary drive units 16 and 17 . After that, with the workpiece W1 supported on the lower part of the support part 18, the support part 18 is lowered as indicated by the white arrow in FIG. As a result, the workpiece W1 is pressed against the wire 11, and the wire 11 cuts the workpiece W1. At this time, the wire 11 performs a traverse operation such that it is reeled out from the reel 12 by a predetermined length LG and then wound on the reel 12 by a predetermined length LB. Through this traverse operation, the cutting of the work W1 by the wire 11 proceeds.

<Tool imaging device 20>
Next, the tool imaging device 20 of this embodiment will be described.
The tool imaging device 20 is a device for imaging the machined surface 40 of the wire 11 . In the present embodiment, the state of the machined surface 40 is determined by using a learned learning device 51 with a captured image (detailed later-described determination image 50) as input data.

<Camera 21>
The tool imaging device 20 has a camera 21 as an imaging section that images the machined surface 40 of the wire 11 . The camera 21 is arranged between the reel 12 and the processing roller 14 so that its imaging portion faces the processing surface 40 of the wire 11 . A camera 21 is connected to the electronic control unit 30 . The electronic control unit 30 controls the operation of the camera 21 . Images captured by the camera 21 are stored in the storage unit 34 of the electronic control device 30 .

<First Illumination Unit 25, Second Illumination Unit 26>
The tool imaging device 20 has a first illumination section 25 and a second illumination section 26 for illuminating the machined surface 40 of the wire 11 .

The first illumination section 25 has a light emitting element 251 as a light source. In this embodiment, when the camera 21 captures an image of the machined surface 40 of the wire 11, the light emitting element 251 is supplied with electric power so that the light emitting element 251 lights up and emits light. The first illumination unit 25 illuminates the surface of the processed surface 40 of the wire 11 that is imaged by the camera 21 (hereinafter referred to as the imaging target surface 27 ) with light emitted from the light emitting element 251 . The first illumination unit 25 is provided in a manner that illuminates a portion of the processing surface 40 that is imaged by the camera 21 . In the present embodiment, the first illumination section 25 and the camera 21 are arranged along the imaging target plane 27 . In this embodiment, more specifically, the direction in which the first lighting unit 25 and the camera 21 are arranged (horizontal direction in FIG. 4) is substantially parallel to the axis of the wire 11 . In this embodiment, the optical axis of the first illumination unit 25 (more specifically, the optical axis of the light emitted from the light emitting element 251) indicated by the arrow OP1 in FIG. The first lighting section 25 is attached.

The second lighting section 26 has a light emitting element 261 as a light source. In this embodiment, when the camera 21 captures an image of the machined surface 40 of the wire 11, the light emitting element 261 is supplied with electric power so that the light emitting element 261 lights up and emits light. The second illumination section 26 illuminates the rear surface 28 of the imaging target surface 27 on the processing surface 40 of the wire 11 with light emitted from the light emitting element 261 . The second lighting section 26 is provided in such a manner that the wire 11 extends between it and the camera 21 . This allows the wire 11 to move between the second lighting section 26 and the camera 21 . In this embodiment, the optical axis of the second illumination unit 26 (specifically, the optical axis of the light emitted from the light emitting element 251) indicated by an arrow OP2 in FIG. The second illumination section 26 is attached in such a manner that the . In addition, in the present embodiment, the second illumination section 26 is attached such that the optical axis of the second illumination section 26 and the axis of the wire 11 are perpendicular to each other.

Here, the surface of the wire 11 (specifically, the surface of the abrasive grains 41) often becomes a substantially arcuate surface as the wire 11 deteriorates due to use. Therefore, when illuminating the imaging target surface 27 of the processing surface 40 (the surface of the abrasive grains 41) by the illumination unit, if so-called vertical epi-illumination, which is illumination from a direction orthogonal to the axis of the wire 11, is adopted, the following phenomenon occurs. There is a risk. In this case, the irradiation light emitted from the illumination unit to the processing surface 40 is reflected by the surface of the processing surface 40 forming a substantially arc surface, and most of the reflected light is directed away from the illumination unit. Deflect and diffuse. On the other hand, of the reflected light reflected on the surface of the processing surface 40, the reflected light traveling in the direction orthogonal to the axial direction of the wire 11 returns to the illumination unit side while maintaining high luminous intensity. Therefore, when vertical epi-illumination is employed, the contrast of the reflected light returning to the illumination unit tends to be high. As a result, the camera 21 may not be able to properly capture the image of the processing surface 40 (image capturing target surface 27).

In this regard, in the present embodiment, when imaging the processed surface 40 by the camera 21 , when the first illumination unit 25 illuminates the imaging target surface 27 of the processed surface 40 , the emitted light from the light emitting element 251 is directed to the axis of the wire 11 . Illuminated from an oblique direction. As a result, the contrast of the reflected light returning to the first illumination section 25 can be made weaker than when the machining surface 40 is illuminated from the direction perpendicular to the axis of the wire 11 . Therefore, the processed surface 40 can be imaged by the camera 21 so that the contrast is suitable for judging the state of the processed surface 40 .

Moreover, in this embodiment, the back surface 28 of the processing surface 40 is illuminated by the second illumination section 26 . As a result, since the outline of the wire 11 becomes clear, the shape of both sides of the wire 11 in the width direction (the surface shape of the abrasive grains 41, the protrusion height of the abrasive grains 41, etc.) becomes clear. Surface 40 can be imaged.

As described above, according to the present embodiment, when imaging the processed surface 40 by the camera 21, the entire processed surface 40 (more specifically, the imaging target surface 27 and its back surface 28) is illuminated by the first illumination section 25 and the second illumination. It can be properly illuminated by the portion 26 . Therefore, the image of the processing surface 40 can be properly captured by the camera 21 .

In this embodiment, operation control of the camera 21 is performed as follows.
In the present embodiment, on the condition that it is the low speed period TVL (time T11 to T12, T15 to T17, T20 to T21 in FIG. 3) in which the moving speed of the wire 11 decreases as the moving direction of the wire 11 is switched. Imaging by the camera 21 is executed.

Further, in the present embodiment, every time an image is captured by the camera 21, the timing for performing the next image capturing by the camera 21 is determined based on the time when the image capturing is performed (execution time TR) and the moving speed V1 of the wire 11. control target value (target execution time TET) is set. Then, at the timing when the target execution time TET has come, the imaging by the camera 21 is executed.

FIG. 5 shows the relationship between the imaging range (S1, S2, S3, S4) of the camera 21 and the machined surface 40 of the wire 11. As shown in FIG. As shown in FIG. 5, in order to efficiently determine the entire processed surface 40 based on an image captured by the camera 21 (determination image 50), an imaging mode in which portions that are not imaged or portions that are imaged redundantly is reduced. Then, it is preferable that the imaging by the camera 21 is executed.

As is clear from FIG. 5, in order to realize such an imaging mode, the wire 11 must be extended by a length LS in the moving direction (horizontal direction in FIG. 5) of the imaging range (S1, S2, S3, S4) by the camera 21. The camera 21 may take an image every time it moves. Here, the time ΔT (=LS/V1) required for the wire 11 to move by the “length LS” can be obtained from the “length LS” and the moving speed V1 of the wire 11 . Then, by setting the timing (target execution time TET) of the next imaging to the timing advanced by the time ΔT from the timing (execution time TR) of imaging by the camera 21, the camera 21 in the above-described imaging mode can be set. Imaging by is realized.

In this embodiment, the relationship between the execution time TR, the movement speed V1, and the target execution time TET is obtained in advance, and is stored in the storage unit 34 of the electronic control unit 30 as an arithmetic expression used for setting the target execution time TET. ing. When imaging by the camera 21 is performed in the low speed period TVL, the target execution time TET is set from the above equation based on the execution time TR of imaging by the camera 21 and the moving speed V1 of the wire 11 .

<Electronic control unit 30>
As shown in FIG. 1, the storage unit 34 of the electronic control unit 30 has a storage area for storing various execution programs 52 and a storage area for storing teacher data 53 used for machine learning of the learning device 51. ing. The storage unit 34 has a storage area for storing a learned learning device 51 (more specifically, learning data created through execution of machine learning). The storage unit 34 also stores a storage area for storing an image (determination image 50) of the processed surface 40 of the wire 11 to be determined, and determination result data 54 indicating the result of determining the state of the processed surface 40 of the wire 11. It has a storage area for storing.

The electronic control unit 30 executes various processes related to imaging of the machined surface 40 by the camera 21 and various processes related to determination of the state of the machined surface 40 of the wire 11 based on various calculation results. In this embodiment, the control section having the CPU 31, the ROM 32, and the RAM 33 corresponds to the target setting section and the imaging execution section.

The execution program 52 includes an imaging program for causing the camera 21 to perform imaging. The execution program 52 also includes a program for causing the learning device 51 to perform machine learning and for generating learning data, which is data indicating the execution result of the machine learning. Further, the execution program 52 includes a determination program for executing processing (determination processing) for determining the state of the machined surface 40 of the wire 11 .

The teacher data 53 is data for performing machine learning of the learner 51 so as to acquire the ability to determine the state of the machined surface 40 of the wire 11 .
<Learning device 51>
In this embodiment, as the learner 51, a Generative Adversarial Network (GAN) is adopted. In this embodiment, machine learning is performed by the learning device 51 based on the teacher data 53 stored in the storage unit 34 . More specifically, a learning process of extracting one of the plurality of images that make up the teacher data 53 and using the same image as input data to cause the learning device 51 to perform machine learning is repeatedly executed for each image that makes up the teacher data 53. . Learning data created through execution of machine learning is stored in the storage unit 34 . In this embodiment, an execution program 52 is constructed and stored in the storage unit 34 so that a series of processing related to machine learning by the learning device 51 is automatically executed.

As conceptually shown in FIG. 6, the machine learning of the learning device 51 is, in detail, the input data and the generated image data generated by the learning device 51 based on the same input data. (Image A) is executed. A value corresponding to the difference between the input data and the generated image data (hereinafter referred to as generation error ΔP) is output from the learning device 51 that has already been trained. As a result, when the learning device 51 is properly learned, when the determination processing for determining the state of the wire 11 to be determined (more specifically, the machined surface 40 thereof) is executed, the learning device 51 outputs the following: A value (generated error ΔP) is output. In this embodiment, the generated error ΔP corresponds to the index value of the state of the processing surface 40 corresponding to the determination image 50 .

Here, when acquiring an image that constitutes the teacher data 53 (FIG. 1), the image of the processing surface 40 is captured by the camera 21 as follows. In this case, an unused wire 11 is prepared and attached to the wire saw 10 . Then, the wire saw 10 is operated without machining the work W1. In this state, the camera 21 captures an image of the machined surface 40 of the wire 11 , and the captured image is stored in the storage section 34 of the electronic control unit 30 as an image forming the teaching data 53 . In addition to using the wire saw 10 and the tool imaging device 20 of the present embodiment, it is also possible to use a separate device when acquiring the images that constitute the teacher data 53 .

Further, when obtaining the determination image 50, the image of the processing surface 40 is captured by the camera 21 as follows. In this case, while the wire saw 10 is operated to machine the work W1, the camera 21 takes an image of the machined surface 40 of the wire 11, and the imaged image is used as the determination image 50 by the electronic control unit 30. is stored in the storage unit 34 of the

Therefore, when the processing surface 40 of the wire 11 to be determined is in an unused state when executing the determination process, the input data (determination image 50) and the generated image data generated by the learning device 51 are substantially the same. become. Therefore, in this case, the generated error ΔP output from the learning device 51 becomes a very small value (for example, "0").

On the other hand, when the wire 11 is used to some extent and the machined surface 40 is in a degraded state when executing the determination process, as conceptually shown in FIG. The image B1) and the generated image data (image B2) do not match. In this case, the generated error ΔP output from the learning device 51 becomes a “positive value” corresponding to the difference between the input data and the generated image data. Moreover, in this case, the greater the difference between the actual state and the unused state, the greater the difference between the input data and the generated image data. become. Therefore, in the determination process using the learning device 51, it can be determined that the deterioration of the machined surface 40 of the wire 11 progresses as the value of the generation error ΔP increases.

<State of wire 11>
As shown in FIG. 5, the wire 11 has a structure in which a plurality of abrasive grains 41 are bonded to the outer surface of a core material made of metal wire with a binder 43 . A machined surface 40 of the wire 11 has an elongated shape extending in the moving direction. As the wire 11 is used, the state of the machined surface 40 of the wire 11 changes as follows.

As shown in FIG. 8(a), in the unused wire 11, since the abrasive grains 41 are not abraded, the tips of the abrasive grains 41 are sharp. As shown in FIG. 8(b), as the processing surface 40 deteriorates with use of the wire 11, the tips of the abrasive grains 41 gradually flatten. As shown in FIG. 8(c), as the deterioration of the machined surface 40 of the wire 11 progresses, the amount of projection of the abrasive grains 41 from the layer of the binder 43 on the wire 11 becomes smaller. Further, as the deterioration of the processed surface 40 of the wire 11 progresses, the layer of the binder 43 on the wire 11 cracks as shown in FIG. Part of the layer 43 may be peeled off. In addition, as the wire 11 is used, shavings adhere to the surface of the binder 43 or the surface of the binder 43 is scraped, so that the outermost peripheral surface of the processing surface 40 of the wire 11 extends in the moving direction. Some parts may appear. In the present embodiment, the state of the machined surface 40 can be determined by capturing the "characteristic portion" that appears on the machined surface 40 of the wire 11 as the wire 11 is used.

<Statistical processing>
In the present embodiment, when determining the machined surface 40 of the wire 11, an index value for the state of the wire 11 is calculated by performing statistical processing on the "generated error ΔP". In the present embodiment, as the index value, the median value of the "generation error ΔP" output from the learning device 51 and stored in the storage unit 34 of the electronic control unit 30 during a predetermined period TJ is calculated. . Then, the state of the machined surface 40 of the wire 11 is determined based on this index value. As described above, it can be determined that the deterioration of the machined surface 40 progresses as the "generation error ΔP" increases. can be determined to be

As the predetermined period TJ, one reciprocating period of the wire 11 is composed of a [forward movement] period in which the wire 11 is paid out by a predetermined length LG and a [backward movement] period in which the wire 11 is wound by a predetermined length LB immediately after. It is defined. In the present embodiment, the "generated error ΔP" stored in the storage unit 34 of the electronic control unit 30 is taken in during the predetermined period TJ, and the "generated error ΔP" is subjected to statistical processing to An index value (the median value above) for the condition is calculated.

By performing such statistical processing, it is possible to grasp the output tendency of the "generation error ΔP" in the predetermined period TJ, so based on these "generation error ΔP", the state of the machined surface 40 of the wire 11 can be determined over a wide range. can do. As a result, it is possible to prevent the state of the entire machined surface 40 from being erroneously judged based on the judgment result of a part of the machined surface 40, as in the following [erroneous judgment 1] and [erroneous judgment 2]. can. [Incorrect judgment 1] Although the deterioration of the entire machined surface 40 has progressed, it is judged that the deterioration of the machined surface 40 has not progressed in a small part, so the deterioration of the machined surface 40 has not progressed. is determined. [Incorrect judgment 2] Although the deterioration of the entire machined surface 40 has not progressed, it is judged that the deterioration of the machined surface 40 has progressed in only a small part, so the deterioration of the machined surface 40 has progressed. is determined.

<Reflection of judgment results>
In the present embodiment, the determination result (specifically, the median value) of the determination process is reflected in the operation control of the rotation drive units 16 and 17 of the wire saw 10 (FIG. 1). Specifically, when the median value calculated in the determination process is equal to or greater than the determination value, a value (=LG+α) obtained by adding a predetermined value α to the “predetermined length LG” in the [forward movement] is used as a new predetermined value. defined as length LG. On the other hand, when the median value is less than the judgment value, a value (=LG-α) obtained by subtracting the predetermined value α from the "predetermined length LG" is determined as the new predetermined length LG.

Here, when the median value is large, it can be seen that the generation error ΔP tends to increase during the predetermined period TJ, so it can be determined that the wire 11 has deteriorated more than expected. In this case, since the work W1 is machined by the wire 11 in a state deteriorated more than expected, the machining accuracy of the work W1 may be lowered.

In this embodiment, in such a case, by increasing the predetermined length LG in [forward movement], the new feed amount of the wire 11, more specifically, from the predetermined length LG in [forward movement] to the predetermined length in [backward movement] The amount obtained by subtracting the length LB (=LG-LB) is increased. Therefore, the update time for updating the portion of the wire 11 that is used for machining the work W1 is shortened. Thereby, the machining accuracy of the workpiece W1 by the wire saw 10 can be maintained at a high level.

On the other hand, when the median value is small, it can be seen that the generation error ΔP tends to be small during the predetermined period TJ, so it can be determined that the deterioration of the wire 11 has not progressed as expected. In this case, although the machining accuracy of the work W1 can be kept high, there is a possibility that the wire 11 has been updated even though it is still usable. In this embodiment, in such a case, the new feeding amount of the wire 11 is reduced by reducing the predetermined length LG in the [forward motion]. As a result, the update time can be lengthened, so that the usage period of the wire 11 can be extended.

In the present embodiment, from the results of various experiments and simulations by the inventors, etc., the judgment value and the predetermined value α are set in advance so that the life of the wire 11 can be extended while maintaining the machining accuracy of the workpiece W1 at a high level. It has been demanded. These determination values and the predetermined value α are incorporated in the execution program for operating the wire saw 10 and stored in the storage section 34 of the electronic control unit 30 .

<Camera control processing>
Processing (camera control processing) related to operation control of the camera 21 will be specifically described below. FIG. 9 shows the execution procedure of camera control processing. A series of processes shown in the flowchart of FIG. 9 are executed by the electronic control unit 30 as processes at predetermined time intervals.

As shown in FIG. 9, in this process, first, it is determined whether or not the operation period of the wire saw 10 is the low speed period TVL (see FIG. 3) (step S11). Then, if it is not the low speed period TVL (step S11: NO), this process is terminated without executing the following processes (processes of steps S12 to S15).

When the operation period of the wire saw 10 is the low speed period TVL (step S11: YES), it is determined whether or not the target execution time TET has come (step S12). In the present embodiment, when the low speed period TVL is reached, the time at this time is set as the target execution time TET. Then, if the target execution time TET has not yet reached (step S12: NO), this process ends without executing the following processes (processes of steps S13 to S15).

After that, when the target execution time TET comes (step S12: YES), the image of the processing surface 40 is captured by the camera 21 (step S13). Also, the moving speed V1 of the wire 11 at this time is detected (step S14). In this embodiment, the rotary drive unit 16 calculates the rotational speed VM of the servomotor 16M based on the output signal of the encoder 16E. In the process of step S14, the rotational speed VM is taken into the electronic control unit 30 as the moving speed V1 of the wire 11. FIG. In this embodiment, the rotation drive section 16 corresponds to the speed detection section.

Then, based on the movement speed V1 of the wire 11 and the current imaging execution time TR (more specifically, the target execution time TET), a new target execution time TET is set from the above equation (step S15). . After this, this process is executed based on the newly set target execution time TET. After the target execution time TET is set in this way, this process is terminated.

As described above, in the camera control process, a process of capturing an image by the camera 21 and setting a new target execution time TET in accordance with the image capturing is repeatedly performed. In the present embodiment, captured images acquired through camera control processing are used as the images forming the teacher data 53 and the determination image 50 .

<Operation control processing>
Next, various processing (operation control processing) relating to the operation of the wire saw 10 will be specifically described. FIG. 10 shows the execution procedure of the operation control process. The series of processes shown in the flowchart of FIG. 10 is performed by the electronic control unit 30 as a process for each predetermined time period on the condition that the operation control of the rotation drive units 16 and 17 and the operation control of the camera 21 are being executed. performed by

As shown in FIG. 10, in this process, first, it is determined whether or not the determination image 50 has been acquired through the camera control process (step S21). If it is determined that the judgment image 50 has not been newly acquired (step S21: NO), this process ends without executing the following processes (processes of steps S22 to S26).

After that, when this process is repeatedly executed and a new determination image 50 is acquired (step S21: YES), the generated error ΔP is output from the learned learning device 51 using this determination image 50 as input data. (step S22). Then, this generated error ΔP is stored in the storage unit 34 of the electronic control unit 30 (step S23).

Thereafter, it is determined whether or not the generated error ΔP has been stored for a predetermined period of time TJ (step S24). If it is determined that the period during which the generation error ΔP is stored has not reached the predetermined period TJ (step S24: NO), the process ends without executing the following processes (steps S25 and S26). be done.

After that, this process is repeatedly executed, and when it is determined that the generation error ΔP has been stored for the predetermined period TJ (step S24: YES), the index value (the median value) for the state of the wire 11 is calculated ( step S25). In the processing of step S25, the median value of the generated errors ΔP is calculated as the index value by performing statistical processing on the generated errors ΔP stored during the predetermined period TJ.

Then, based on the index value (the median value) of the state of the wire 11, the predetermined length LG in the [forward movement] is corrected (step S26). As a result, the rotation drive units 16 and 17 are subsequently controlled based on the predetermined length LG corrected in step S26. After the predetermined length LG is corrected in this manner, this process is terminated.

<Effect>
According to this embodiment, the effects described below can be obtained.
(1-1) A moving speed V1 of the wire 11 is detected, and a target execution time TET for the next imaging execution time is set based on the moving speed V1. Then, imaging by the camera 21 is executed based on this target execution time TET.

According to the present embodiment, it is possible to set the timing (specifically, the target execution time TET) for executing the imaging of the machined surface 40 thereafter according to the actual moving speed V1 of the wire 11 at that time. . Therefore, when repeatedly imaging the processing surface 40 while the processing surface 40 is moving, the interval between the imaging portions that are actually imaged can be determined with high accuracy. As a result, it is possible to obtain a captured image of the entire processed surface 40 of the wire 11 with high accuracy in accordance with a previously assumed mode. Specifically, a captured image of the entire processed surface 40 of the wire 11 can be obtained in a mode in which the portions that are not captured by the camera 21 and the portions that are captured redundantly are reduced.

(1-2) The wire saw 10 performs machining with the wire 11 while reciprocating the wire 11 in the axial direction. The imaging by the camera 21 is performed only during the low-speed period TVL in which the moving speed V1 of the wire 11 decreases as the moving direction of the wire 11 is switched.

Here, when capturing images of the machining surface of a tool that is moving at high speed, it is necessary to employ an expensive camera capable of capturing images at high speed. A tool imaging device 20 of the present embodiment is applied to a wire saw 10 which is a processing device in which a wire 11 as a tool moves at high speed. However, in the tool imaging device 20, imaging of the machined surface 40 of the wire 11 is performed only during the low speed period TVL in which the moving speed V1 of the wire 11 is low. Therefore, a relatively inexpensive camera 21 that is not compatible with high-speed imaging can be used. Thereby, the tool imaging device 20 can be configured at low cost.

The low speed period TVL includes a period during which the moving speed V1 of the wire 11 is accelerated (time T11-T12, T16-T17 in FIG. 3) and a period during which the moving speed V1 of the wire 11 is decelerated (time T15- T16, T20 to T21). Since this low-speed period TVL is a period in which the movement direction of the wire 11 is switched, it can be said that it is a period in which the movement speed V1 of the wire 11 changes greatly. According to this embodiment, in such a low-speed period TVL, the timing of executing the imaging of the machined surface 40 of the wire 11 can be accurately set according to the actual change in the moving speed V1 of the wire 11 . Thereby, a captured image can be obtained with high positional accuracy.

(Second embodiment)
A second embodiment of the tool imaging device will be described below with reference to FIGS. 11 and 12, focusing on differences from the first embodiment. In the following description, configurations having the same functions as those of the first embodiment are denoted by the same reference numerals, and overlapping descriptions of these configurations are omitted.

The present embodiment differs from the first embodiment only in the manner in which the operation control of the camera 21 is executed.
<Operation Control of Camera 21>
Hereinafter, an execution mode of operation control of the camera 21 in this embodiment will be described.

In the present embodiment, part of the first captured image P1 captured at the first execution time TR1 and part of the second captured image P2 captured at the second execution time TR2 immediately after the first execution time TR1 are A target execution time TET is set for each execution time in an overlapping manner.

FIG. 11 shows the execution procedure of camera control processing according to this embodiment. A series of processes shown in the flowchart of FIG. 11 are executed by the electronic control unit 30 as processes at predetermined time intervals.

As shown in FIG. 11, in this process, when the operation period of the wire saw 10 reaches the low speed period TVL (step S11: YES) and the target execution time TET (step S12: YES), the surface 40 to be machined by the camera 21 is is performed (step S13).

Based on the first captured image P1 captured at the previous execution time (hereinafter referred to as the first execution time TR1) and the second captured image P2 captured at the current execution time (hereinafter referred to as the second execution time TR2) Then, the moving speed V2 of the wire 11 is detected (steps S31 and S32).

Specifically, the first picked-up image P1 and the second picked-up image P2 are read, and by performing image processing on the images P1 and P2, the overlapping portion PD in each of the images P1 and P2 is specified (step S31). ). After that, the moving speed V2 of the wire 11 is detected based on the relationship between the position of the overlapping portion PD in the first captured image P1 and the position of the overlapping portion PD in the second captured image P2 (step S32).

FIG. 12 shows the relationship between the position of the overlapping portion PD in the first captured image P1 and the position of the overlapping portion PD in the second captured image P2. As is clear from FIG. 12, the displacement amount of the overlapping portion PD between the first captured image P1 and the second captured image P2 is the wire 11 displacement from the first execution time TR1 to the second execution time TR2. It can be the moving distance LD. Also, the time difference between the first execution time TR1 and the second execution time TR2 is the movement time TD required for the wire 11 to move from the position corresponding to the first captured image P1 to the position corresponding to the second captured image P2. can do. Furthermore, by using the movement distance LD and the movement time TD of the wire 11, the movement speed V2 (=LD/TD) of the wire 11 during the period from the first execution time TR1 to the second execution time TR2 can be obtained. can be done. In the present embodiment, a detection program for detecting the moving speed V2 of the wire 11 from the first captured image P1 and the second captured image P2 is built in advance based on such an idea, and stored in the storage section 34 of the electronic control device 30. stored in In this embodiment, the control section having the CPU 31, the ROM 32 and the RAM 33 in the electronic control unit 30 (see FIG. 1) corresponds to the overlap identification section and the speed detection section that identify the overlapping portion PD.

As shown in FIG. 11, after the moving speed V2 of the wire 11 is detected in this manner, the execution time of the next imaging is determined based on the moving speed V2 and the second execution time TR2, which is the current execution time. is set (step S33). After this, this process is executed based on the newly set target execution time TET. After the target execution time TET is set in this way, this process is terminated.

In the process of step S33, a part of the second captured image P2 captured this time and a part (for example, about 1/4) of the captured image (hereinafter referred to as the third captured image P3) to be captured next time overlap, A target execution time TET is set. In this embodiment, the relationship between the second execution time TR2, the moving speed V2, and the target execution time TET is obtained in advance, and stored in the storage unit 34 of the electronic control unit 30 as an arithmetic expression used for setting the target execution time TET. remembered. Then, in the process of step S33, the target execution time TET is set from the above-described arithmetic expression based on the movement speed V2 and the second execution time TR2.

In the camera control process according to the present embodiment, a process of capturing an image by the camera 21 and setting a new target execution time TET in accordance with the capturing is repeatedly performed. In the present embodiment, captured images acquired through camera control processing are used as images forming teacher data 53 and judgment images 50 .

<effect>
According to this embodiment, the following effects can be obtained.
(2-1) Part of the first captured image P1 captured at the first execution time TR1 and part of the second captured image P2 captured at the second execution time TR2 immediately after the first execution time TR1 A target execution time TET is set for each execution time in an overlapping manner. According to this embodiment, the moving speed V2 of the wire 11 can be detected based on the relationship between the position of the overlapping portion PD in the first captured image P1 and the position of the overlapping portion PD in the second captured image P2.

(2-2) According to the present embodiment, effects similar to those described in (1-1) and (1-2) above can be obtained.
(Third embodiment)
A third embodiment of the tool imaging device will be described below with reference to FIGS. 13 and 14, focusing on differences from the first and second embodiments. In the following, configurations having the same functions as those of the first embodiment and the second embodiment are denoted by the same reference numerals, and overlapping descriptions of these configurations are omitted.

The present embodiment differs from the first and second embodiments only in the manner in which operation control of the camera 21 is executed.
<Operation Control of Camera 21>
Hereinafter, an execution mode of operation control of the camera 21 in this embodiment will be described.

As shown in FIG. 13, in the present embodiment, the control target value (target execution time TET) is set.

Further, in this embodiment, when the machined surface 40 of the wire 11 is repeatedly used, the camera 21 performs imaging at the timing when the wire 11 reaches the same movement position, and the target execution time TET at each execution time is set.

FIG. 13(a) shows the imaging range (S1 to S4) of the camera 21 when the machined surface 40 of the wire 11 is used for the Nth time. 13(b) shows the imaging range of the camera 21 during the [N+1]th use, and FIG. 13(c) shows the imaging range of the camera 21 during the [N+M]th use.

According to the present embodiment, as shown in FIGS. 13(a) to 13(c), when the same portion of the processing surface 40 of the wire 11 is repeatedly used, each time the same portion is used, the captured image of the same portion ( A determination image 50) can be acquired. As a result, it is possible to obtain a plurality of judgment images 50 in which the same portion of the machined surface 40 of the wire 11 shows a change in state due to repeated use.

FIG. 14 shows the execution procedure of camera control processing according to this embodiment. A series of processes shown in the flowchart of FIG. 14 are executed by the electronic control unit 30 as processes at predetermined time intervals.

As shown in FIG. 14, in this process, when the operation period of the wire saw 10 reaches the low speed period TVL (step S11: YES) and reaches the target execution time TET (step S12: YES), the surface 40 to be machined by the camera 21 is is performed (step S13).

Thereafter, the moving speed V3 of the wire 11 and the moving position PR of the wire 11 are detected (step S41). In this embodiment, the rotary drive unit 16 calculates the rotation speed VM and the rotation phase PM of the servomotor 16M based on the output signal of the encoder 16E. In the process of step S41, the rotational speed VM is taken into the electronic control device 30 as the moving speed V3 of the wire 11, and the rotational phase PM is taken into the electronic control device 30 as the moving position PR of the wire 11. FIG. In this embodiment, the encoder 16E corresponds to a position detection section that detects the movement position of the machining surface 40 in the movement direction.

Also, in this process, a control target value (target execution position TEP) for the movement position of the wire 11 for executing the next imaging is read (step S42). In this embodiment, the camera 21 captures images at predetermined position intervals. A control target value (target execution position TEP) for the movement position of the wire 11 for executing each imaging is set in advance and stored in the storage unit 34 of the electronic control unit 30 . In the process of step S42, the target execution position TEP for the movement position of the wire 11 for executing the next imaging is read from the data stored in the storage unit 34 each time.

Then, the target execution time TET is set based on the movement speed V3, the movement position PR, and the target execution position TEP (step S43). After this, this process is executed based on the newly set target execution time TET. After the target execution time TET is set in this way, this process is terminated.

Here, the distance between the movement position PR and the target execution position TEP can be the movement distance LD of the wire 11 from the movement position PR to the target execution position TEP. Further, by using the movement distance LD and the movement speed V3 of the wire 11, the movement time TD (=LD/V3) for the movement position of the wire 11 from the movement position PR to the target execution position TEP can be obtained. can be done. By setting the timing at which the movement time TD has passed as the target execution time TET, it is possible to capture an image with the camera 21 at the target execution position TEP. In the present embodiment, based on this idea, a setting program for setting the target execution time TET based on the movement speed V3, the movement position PR, and the target execution position TEP is constructed in advance, and stored in the electronic control unit 30. stored in unit 34.

<effect>
According to this embodiment, the following effects can be obtained.
(3-1) When the same portion of the machined surface 40 of the wire 11 is used repeatedly, a captured image (determination image 50) of the same portion can be obtained each time the same portion is used. As a result, it is possible to obtain a plurality of determination images 50 in which the same portion of the processing surface 40 shows a change in state due to repeated use.

(3-2) According to the present embodiment, effects similar to those described in (1-1) and (1-2) above can be obtained.
(Other embodiments)
It should be noted that each of the above-described embodiments can be implemented with the following modifications. Each of the above-described embodiments and the following modifications can be implemented in combination with each other within a technically consistent range.

In the first embodiment, the timing of detecting the moving speed V1 of the wire 11 and the timing of setting the target execution time TET for the execution time of the next imaging are such that the setting of the target execution time TET is in time for the execution of the next imaging. can be changed arbitrarily. For example, at the timing when a predetermined period of time has passed since the camera 21 has taken an image, a process of detecting the moving speed V1 of the wire 11 and a process of setting a target execution time TET for the execution time of the next imaging are executed. You may make it

- In the second embodiment, the camera 21 captures an image in which a part of the first captured image P1 and a part of the second captured image P2 overlap, instead of performing it every other time. Alternatively, it may be executed at predetermined intervals, such as every two times.

In the third embodiment, when the wire 11 is repeatedly used to machine the surface 40, the target execution time TET is set if the camera 21 performs imaging at the timing when the wire 11 reaches the same movement position. The execution mode of processing can be changed arbitrarily. For example, according to the deviation between the target execution position TEP and the actual execution position (moving position PR) for the current image pickup by the camera 21, feedback control is performed on the execution time (target execution time TET) of the next image pickup by the camera 21. You may do so.

- In the first embodiment or the third embodiment, the imaging by the camera 21 may be performed in an imaging mode in which the portion not imaged by the camera 21 is set to a certain amount.

- In each embodiment, a plurality of cameras 21 that capture images of the processing surface 40 of the wire 11 may be provided. In this case, the target execution time TET for each of the cameras may be set in such a manner that a plurality of imaged portions imaged by a plurality of cameras are arranged in order in the movement direction of the wire 11 . According to the above configuration, the entire processing surface 40 can be imaged in a manner shared by a plurality of cameras, so compared to an apparatus provided with only one camera, the execution interval of imaging by each camera is lengthened. be able to. As a result, relatively inexpensive cameras that are not compatible with high-speed imaging can be used as individual cameras.

FIG. 15 shows an example of such a tool imaging device. As shown in FIG. 15, the tool imaging device of this example has two cameras 21A and 21B. The cameras 21A and 21B are arranged between the reel 12 and the processing roller 14 so that their imaging portions face the processing surface 40 of the wire 11 and are arranged side by side in the moving direction of the wire 11. there is The cameras 21A and 21B are connected to the electronic control unit 30. As shown in FIG. The electronic control unit 30 controls the operation of the cameras 21A and 21B. The images captured by the cameras 21A and 21B are stored in the storage section 34 of the electronic control device 30. FIG. In the operation control of the cameras 21A and 21B, a target image for each camera 21A and 21B is set in such a manner that an imaged portion imaged by one camera 21A and an imaged portion imaged by the other camera 21B are alternately arranged in the movement direction. The execution time TET is set for each.

In the above device, part of the first captured image captured by the camera 21A in the first execution period and part of the second captured image captured by the camera 21B in the second execution period after the first execution period are The imaging by the cameras 21A and 21B may be performed in an overlapping manner. According to this configuration, by performing image processing on the first captured image and the second captured image, it is possible to specify the overlapping portion PD in the first captured image and the second captured image. Then, the moving speed of the wire 11 can be detected based on the relationship between the position of the overlapping portion PD in the first captured image and the position of the overlapping portion PD in the second captured image.

Also, when a plurality of cameras 21 are provided, it is preferable to provide the first illumination section 25 and the second illumination section 26 separately for each of the cameras 21 . In the example shown in FIG. 15, a first lighting unit 25A and a second lighting unit 26A are provided corresponding to one camera 21A, and a first lighting unit 25B and a second lighting unit 26B are provided corresponding to the other camera 21B. is provided.

- In each embodiment, the structure in which the optical axis of the second illumination unit 26 and the axis of the wire 11 are perpendicular to each other is not limited to the structure, and the angle formed by the optical axis of the second illumination unit 26 and the axis of the wire 11 is A structure having an angle slightly inclined from the right angle can be adopted. In addition, it is also possible to employ a structure in which the optical axis of the second lighting section 26 and the axis of the wire 11 are twisted.

- In each embodiment, the position where the optical axis of the first illumination unit 25 and the axis of the wire 11 are twisted is not limited to adopting a structure in which the optical axis of the first illumination unit 25 and the axis of the wire 11 intersect. It is also possible to adopt a structure that becomes

- In each embodiment, a plurality of first lighting units 25 may be provided for one camera 21 . According to the same configuration, the imaging target surface 27 of the processing surface 40 of the wire 11 can be illuminated from a plurality of directions while suppressing bias by the first illumination units 25 .

- In each embodiment, the first lighting unit 25 and the second lighting unit 26 may be omitted as long as the image of the processing surface 40 can be properly captured by the camera 21 .
- In each embodiment, the predetermined period TJ is not limited to one reciprocation period of the wire 11, and any period can be set. As the predetermined period TJ, for example, it is possible to set a multiple reciprocating period in which both the [forward motion] and the [backward motion] of the wire 11 are performed multiple times. In addition, as the predetermined period TJ, it is possible to set a period during which the wire 11 moves once [forward motion], or set a period during which the wire 11 moves once [backward motion].

- In each embodiment, the timing at which the camera 21 takes an image of the processing surface 40 can be set arbitrarily. For example, the imaging by the camera 21 may be executed during the constant speed period (time T13-T14, T18-T19 in FIG. 3). In addition, it is possible to perform imaging by the camera 21 only while the wire 11 is moving forward, or to perform imaging by the camera 21 only during the period when the wire 11 is moving backward. Note that the predetermined period TJ can be arbitrarily set in accordance with the execution mode of imaging by the camera 21 .

- In each embodiment, as the statistical processing to be applied to the generation error ΔP stored in the predetermined period TJ, in addition to adopting the processing of calculating the median value, the processing of calculating the average value, the most frequent A process of calculating the value can be adopted. Arbitrary processing can be adopted as the statistical processing as long as it is possible to calculate a value that moderately represents the tendency of the generation error ΔP stored during the predetermined period TJ.

In each embodiment, the reflection mode of reflecting the determination result (specifically, the median value) of the determination process in the operation control of the rotation drive units 16 and 17 is the following [Reflection mode 1] and [Reflection mode 2 ] can be arbitrarily modified as an example.

[Reflection mode 1] A new " Predetermined length LG" is calculated.

[Reflection mode 2] When the median value calculated in the determination process is equal to or greater than the determination value, the value obtained by subtracting the predetermined value β from the "predetermined length LB" in the above [Return movement] (= LB - β) is newly added. is defined as a predetermined length LB. On the other hand, when the median value is less than the judgment value, a value obtained by adding a predetermined value β to the "predetermined length LB" (=LB+β) is determined as a new predetermined length LB.

The point is that the [forward movement] is changed according to the determination result of the determination process so that the state of the machined surface 40 of the wire 11 can be extended while maintaining high machining accuracy. It suffices if the predetermined length LG and the predetermined length LB of the [backward movement] can be adjusted.

- In each embodiment, the process of reflecting the determination result (specifically, the median value) of the determination process in the operation control of the rotary drive units 16 and 17 (the process of step S26 in FIG. 10) may be omitted. With such a configuration, the state of the machined surface 40 of the wire 11 can also be determined.

- In each embodiment, a convolutional neural network (CNN) can be adopted as the learner 51 . In this case, the machine learning of the learner 51 may be performed so as to enable classification of the state of the machined surface 40 .

As the class classification in this case, it is possible to adopt the class classification of the deterioration state of the machined surface 40 (see FIGS. 8(a) to 8(e)). According to this configuration, data indicating the deterioration state of the machined surface 40 can be output from the learned learning device 51 using the determination image 50 as input data.

Further, as the class classification, a class classification regarding the dispersed state of the abrasive grains 41 on the processing surface 40 of the wire 11 can be adopted. Here, the dispersion state of the abrasive grains 41 on the processing surface 40 may be a dense state in which the number of abrasive grains 41 arranged per unit area is relatively large as shown in FIG. As shown in , it becomes an average state in which the number of identical arrangements is an average number. Moreover, as shown in FIG. 16(c), the dispersed state of the abrasive grains 41 on the processing surface 40 may be a coarse state in which the number of the abrasive grains 41 arranged per unit area is relatively small. According to the above configuration, the determination image 50 is used as input data, and output data indicating the dispersed state of the abrasive grains 41, examples of which are shown in FIGS. be able to. As a result, for example, in an inspection process in the manufacturing process of the wire 11, the output data can be used to inspect the dispersed state of the abrasive grains 41 on the processing surface 40 of the wire 11. FIG.

- The tool imaging device according to each of the above embodiments can also be applied to a wire electric discharge machine. An example of such a wire electric discharge machine 60 is shown in FIG. As shown in FIG. 17, the wire electric discharge machine 60 has a wire 61, which is a tool used for machining the work W2, and a pair of reels 62, 63 around which the wire 61 is wound. A rotary drive unit (not shown) is connected to each of the reels 62 and 63 . When the work W2 is machined by the wire electric discharge machine 60, the reels 62 and 63 are rotationally driven such that the wire 11 is let out from one reel 62 and wound by the other reel 63. As shown in FIG. The wire electric discharge machine 60 has a power supply device 64 . During machining of the work W2, the positive terminal of the power supply 64 is connected to the wire 61 and the negative terminal of the power supply 64 is connected to the work W2. The wire electric discharge machine 60 has a moving device (not shown) for moving the work W2 relative to the wire 61 when machining the work W2. The wire electric discharge machine 60 has a camera 65 for imaging the machined surface 611 of the wire 61 . The imaging portion of the camera 65 faces the portion of the processing surface 611 of the wire 11 after passing the work W2. Images captured by the camera 65 are stored in a storage unit (not shown) of the electronic control unit.

In the tool imaging device applied to the wire electric discharge machining device 60, the learner learned by the teacher data is stored in the storage section of the electronic control device. Then, an image (determination image) captured by the camera 21 is used as input data, and an index value (generated error) of the state of the machined surface 611 is output from the learned learner.

Here, the wire 61 is wire-shaped and has a processed surface 611 on its outer surface. Specifically, a metal wire (for example, brass wire or galvanized brass wire) is used as the wire 61 . As the wire 61 deteriorates with use, the machined surface 611 becomes uneven. According to the above configuration, it is possible to detect the shape change of the machined surface 611 of the wire 61 and appropriately determine the state of the machined surface 611 . Further, by adjusting the feeding speed of the wire 61 and the moving speed of the work W2 based on the determination result, it is possible to extend the life of the wire 61 while maintaining high machining accuracy of the work W2.

- The tool imaging device according to each of the above embodiments can also be applied to a grinding device. FIG. 18 shows an example of such a grinding device 70. As shown in FIG. As shown in FIG. 18, the grinding device 70 has a substantially disk-shaped rotary whetstone 71 as a tool used for processing. The rotary grindstone 71 has a structure in which a large number of abrasive grains are dispersed on the outer peripheral surface of a base material and fixed with a binder. A processing surface 711 forming the outer peripheral surface of the emery wheel 71 has an elongated shape extending in the moving direction. The emery wheel 71 is rotatably supported. A rotary drive unit 72 having, for example, a servomotor is connected to the rotary grindstone 71 . The grinding device 70 is capable of relatively moving the rotary grindstone 71 and a work (not shown). In the grinding apparatus 70, the surface of the workpiece is ground by the machining surface 711 of the grindstone 71 by relatively moving the grindstone 71 and the work while rotating the grindstone 71 to bring the grindstone 71 into contact with the work. Grinded. A tool imaging device applied to the grinding device 70 has a camera 73 for imaging a processing surface 711 of the rotary grindstone 71 . In this tool imaging device, the camera 73 repeatedly captures images of the machined surface 711 while the grindstone 71 is rotating, that is, while the machined surface 711 is moving. Images captured by the camera 73 are stored in a storage unit (not shown) of the electronic control unit.

DESCRIPTION OF SYMBOLS 10... Wire saw 11, 61... Wire 20... Tool imaging device 21, 65, 73... Camera 25... 1st illumination part 26... 2nd illumination part 27... Imaging object surface 28... Back surface 30... Electronic control unit 31... CPU
32 ROM
33 RAM
34... Storage unit 40, 611, 711... Machining surface 50... Judgment image 60... Wire electric discharge machine 70... Grinding machine 71... Rotary whetstone

Claims (6)

It is applied to a tool used for processing by a processing device and having a long shape with a processing surface extending in the moving direction of the processing surface, and the processing surface is applied to the processing surface in a state where the processing surface is moving. In a tool imaging device that repeatedly performs imaging of
a speed detection unit that detects a moving speed of the machining surface in the moving direction;
a target setting unit that sets a target value for execution timing for performing the imaging based on the moving speed detected by the speed detection unit;
and an imaging execution unit that performs the imaging based on the target value. The tool is of a type in which the same portion of the machining surface is repeatedly used,
The tool imaging device has a position detection unit that detects a movement position of the machining surface in the movement direction,
The target setting unit performs the imaging at the same moving position when the machining surface is repeatedly used, based on the moving speed detected by the speed detecting unit and the moving position detected by the position detecting unit. 2. The tool imaging device according to claim 1, wherein the target value is set in a manner in which is executed. 3. The tool imaging according to claim 1 or 2, wherein the tool is a wire used for processing by a wire saw as the processing device, and is of a type that is used while reciprocating in the axial direction of the wire. Device. The tool imaging device is
A first illumination unit that illuminates an imaging target surface, which is a surface of the processing surface that is imaged by an imaging unit that images the processing surface, and a second illumination unit that illuminates the back surface of the imaging target surface of the processing surface, with
4. The tool according to claim 3, wherein the optical axis of the first illumination section and the axis of the wire obliquely intersect, and the optical axis of the second illumination section and the axis of the wire intersect. Imaging device. The tool imaging device includes a plurality of imaging units for imaging the machined surface,
2. The target setting unit individually sets the target values for the plurality of image pickup units in a manner in which the plurality of image pickup portions imaged by the plurality of image pickup units are arranged in order in the movement direction. 5. The tool imaging device according to any one of -4. A mode in which the target setting unit partially overlaps a first captured image captured in a first execution period and a part of a second captured image captured in a second execution period subsequent to the first execution period. to set the target value,
The tool imaging device includes an overlap identifying unit that identifies overlapping portions in the first captured image and the second captured image,
6. The speed detection unit detects the moving speed based on a relationship between a position of the overlapping portion in the first captured image and a position of the overlapping portion in the second captured image. The tool imaging device according to any one of .

Images