JP7625915B2 - Cutting process monitoring system - Google Patents

Description

The present invention relates to a cutting processing monitoring system that is used, for example, to prevent problems in cutting processing and deterioration of processing quality.

In lathe machining, it is generally necessary to quickly detect wear or chipping of the tool cutting edge and take action such as replacing the tool. For this reason, a method has been known in the past in which the tool cutting edge is photographed with a camera and the condition of the cutting edge is examined from the image. For example, in Patent Document 1, the tool cutting edge is photographed with a camera in a standby state before and after cutting, and the amount of wear is determined from the binary image. In Patent Document 2, the tool cutting edge during cutting is captured with an infrared camera and the image is learned by a neural network to determine abnormalities.

Japanese Unexamined Patent Publication No. 6-114694 Japanese Patent Application Publication No. 11-267949

However, conventional methods were unable to detect the occurrence of vibrations at the tool tip during cutting. Specifically, it was difficult to detect in real time, for example, vibrations caused by increased cutting resistance due to damage to the tool tip, or chatter vibrations caused by inappropriate cutting conditions.

One of the objectives of the present invention is to provide a cutting process monitoring system that can detect in real time whether or not vibrations are occurring at the cutting edge of a tool during cutting.

One embodiment of the cutting processing monitoring system of the present invention comprises a camera that continuously photographs the tool cutting edge of a turning tool during turning processing , a vibration transmission member that connects the tool cutting edge to the camera directly or via another member and transmits the vibration of the tool cutting edge to the camera, and an analysis unit that analyzes the vibration state of the turning tool based on changes over time in information captured in each image taken by the camera.

In the present invention, the cutting edge of the tool during turning is continuously photographed by a camera, i.e., in real time. In this invention, "continuously photographing" refers to taking at least 10 frames per second. The captured images are then compared over time, and the magnitude and period of camera shake are stored from changes in the image information, and the results are used to determine abnormal vibration during cutting. They can also be used as an index for improving cutting conditions. In this invention, "vibration" includes, for example, vibration caused by increased cutting resistance due to damage to the cutting edge of the tool, and chatter vibration caused by inappropriate cutting conditions.

According to the present invention, the vibration of the tool cutting edge is stably transmitted to the camera by the vibration transmission member, which allows the analysis unit to accurately analyze in real time whether or not vibration is occurring based on image information captured by the camera.
As described above, according to the present invention, the occurrence or non-occurrence of vibrations at the cutting edge of a tool during cutting can be detected in real time.

In the above cutting process monitoring system, it is preferable that the vibration transmission member amplifies the vibration of the tool cutting edge and transmits it to the camera.

In this case, even if the vibration of the tool cutting edge is small, the vibration is amplified by passing through the vibration transmission member, so that the image information captured by the camera shows a stable change over time due to the occurrence of vibration. This makes it possible to detect the occurrence of vibration with greater accuracy. When the vibration transmission member has this effect (function), it can be called a vibration amplification member.

In the above cutting process monitoring system, the analysis unit may analyze whether vibration is occurring based on changes in the contour length of the cutting edge ridge shown in each of the images.

Images continuously captured by a camera during cutting include images in which the cutting edge is hidden by chips, and images in which the cutting edge is difficult to see due to a large amount of adhesion. For example, images in which the outline (edge) of the cutting edge is captured for a predetermined cutting edge length or more can be classified as a predetermined pattern from among the many images continuously captured, and the presence or absence of vibration of the tool cutting edge can be analyzed more accurately by measuring the change over time in the outline length of the cutting edge ridge of each image classified into a predetermined pattern. Specifically, for example, the cutting edge ridge (edge) within the imaging field of view can be detected by image processing such as a canny filter, and the presence or absence of vibration of the cutting edge can be detected by measuring the number of pixels of the edge of each image, that is, the change over time in the outline length of the cutting edge ridge (such as the width and period of increase and decrease in the number of pixels).

In the above cutting process monitoring system, the analysis unit may analyze whether vibration is occurring based on changes in the position of the cutting edge ridge line captured in each of the images.

In this case, the analysis unit measures the distance between one side of the outer frame (outer edge of the imaging field of view) of each image and the cutting edge ridge, for example by image processing. By measuring the amount of positional change over time and the period of the cutting edge ridge, it is possible to analyze the presence or absence of vibration of the tool cutting edge using a simpler method.

In the above cutting process monitoring system, the analysis unit may analyze whether vibration is occurring based on changes in the position of a feature point of the tool cutting edge shown in each of the images.

In this case, the analysis unit measures the change over time in the position of a feature point that constitutes part of the pattern on the rake face, for example, from each image information. This makes it possible to analyze the occurrence of vibration at the tool cutting edge using a simple method. Note that by selecting as feature points parts that are less likely to be affected by chips or adhesion during cutting, in other words parts that are less likely to be hidden by chips or adhesion, the accuracy of the analysis can be improved in a more stable manner.

According to one embodiment of the cutting process monitoring system of the present invention, it is possible to detect in real time whether or not vibrations are occurring at the cutting edge of the tool during cutting.

FIG. 1 is a side view showing an example of a turning device according to a first embodiment. FIG. 2 is a functional block diagram illustrating an example of the cutting process monitoring system according to the first embodiment. FIG. 3 shows an example of an image classified into the first pattern by the classification unit. FIG. 4 shows an example of an image classified into the second pattern by the classification unit. FIG. 5 shows an example of an image classified into the third pattern by the classification unit. FIG. 6 shows an example of analysis (image processing) of an image classified into the first pattern. FIG. 7 is a flowchart showing an example of the process of the cutting work monitoring device according to the first embodiment. FIG. 8 is an example of a graph showing a change over time in the position of the cutting edge line captured in each image acquired in the cutting process monitoring system of the second embodiment. FIG. 9 is a flowchart showing an example of processing of the cutting process monitoring device according to the second embodiment. FIG. 10 is a functional block diagram showing a modification of the cutting process monitoring system of the second embodiment.

First Embodiment
A cutting process monitoring system 10 according to a first embodiment of the present invention will be described with reference to Figures 1 to 7. The cutting process monitoring system 10 of the present embodiment includes a turning machine 20 and a cutting process monitoring device 30.

As shown in Figures 1 and 2, the turning device 20 is a machine tool such as an NC lathe. The turning device 20 is a device that turns a workpiece W, such as a metal workpiece. In other words, the cutting process monitoring system 10 is used for turning (lathe processing) using a machine tool such as an NC lathe. Turning refers to cutting using a turning tool such as a cutting tool.

The turning device 20 includes a turning tool 21, a tool rest 22, a camera 23, a vibration transmission member 24, and a chuck (not shown). In other words, the cutting process monitoring system 10 includes the camera 23 and the vibration transmission member 24.

As shown in FIG. 1, the turning tool 21 is, for example, a replaceable cutting tool in which a cutting insert 26 is removably attached to the tip of a holder 25. That is, the turning tool 21 has a holder 25 and a cutting insert 26. However, the turning tool 21 is not limited to this configuration, and may be, for example, a solid-type cutting tool in which the cutting edge is integrally formed with the holder.

The holder 25 is columnar and extends in one direction. In the example shown in FIG. 1, the direction in which the holder 25 extends is inclined at an angle θ with respect to the horizontal plane H. The angle θ is, for example, 30°. The rear end of the holder 25 is supported by the tool rest 22. The turning tool 21 and the tool rest 22 are fixed together.

The cutting insert 26 is made of, for example, a cemented carbide alloy, etc. The cutting insert 26 is, for example, in the shape of a polygonal plate such as a quadrangular plate, or in the shape of a disk, etc. In this embodiment, the cutting insert 26 is, for example, in the shape of a rhombic plate.
3, the cutting insert 26 has a rake face 26a, a clearance face (not shown), and a cutting edge 26b disposed on a ridge between the rake face 26a and the clearance face. In this embodiment, at least a portion of the cutting insert 26, specifically, a portion including at least the rake face 26a and the cutting edge 26b, may be simply referred to as a "tool cutting edge" or a "cutting edge".

The rake surface 26a is disposed on at least one of a pair of plate surfaces facing the plate thickness direction of the cutting insert 26. As shown in FIG. 1, the rake surface 26a is disposed on one plate surface facing the upper side of the cutting insert 26, i.e., the upper surface. In the example shown in FIG. 1, the rake surface 26a is inclined with respect to the horizontal plane H at approximately the same angle as the angle θ at which the holder 25 is inclined with respect to the horizontal plane H.

As shown in FIG. 5, the rake face 26a of this embodiment has a feature point 26c. The feature point 26c constitutes part of the pattern provided on the rake face 26a. The feature point 26c is provided on the rake face 26a for the purposes of, for example, smooth discharge of the chips C, improving the external design, and improving the distinguishability. In this embodiment, the feature point 26c is, for example, a protruding chip breaker.

As shown in FIG. 1, the cutting edge 26b is disposed at the tip of the turning tool 21. The cutting edge 26b is brought into contact with the workpiece W rotating around the central axis O, whereby the workpiece W is turned to form a machined surface Wa as shown in FIG. 5.

In this embodiment, as shown in FIG. 3, when the upper surface, i.e., the rake surface 26a, of the cutting insert 26 is viewed from the front, the cutting edge 26b is substantially V-shaped. Specifically, this cutting edge 26b has one corner edge that extends in a curved line and a pair of straight edges that are connected to both ends of this corner edge and extend in a straight line.

As shown in FIG. 1, the tool rest 22 supports the turning tool 21. The tool rest 22 moves the turning tool 21 relative to the workpiece W at least in the direction in which the horizontal plane extends, i.e., along the surface direction of the horizontal plane. The tool rest 22 may also move the turning tool 21 in the vertical direction relative to the workpiece W.

The camera 23 is disposed above the turning tool 21 and the workpiece W. The camera 23 is, for example, a global shutter type camera. The camera 23 continuously captures the tool cutting edge. Note that in this embodiment, "continuously captures images" refers to capturing images at least 10 frames per second. Specifically, in this embodiment, the camera 23 continuously captures the tool cutting edge at a speed of, for example, 30 frames per second or more. During cutting, the camera 23 captures the machined surface Wa of the workpiece W as well as the tool cutting edge.

In this embodiment, the camera 23 photographs the tool cutting edge from a direction perpendicular to the cutting surface 26a. Specifically, the camera 23 photographs the tool cutting edge from a direction inclined at a predetermined angle from the vertical direction. This predetermined angle is approximately the same as the angle at which the cutting surface 26a is inclined with respect to the horizontal plane H (corresponding to angle θ). The distance between the camera 23 and the tool cutting edge is, for example, 300 mm or more.

The camera 23 is fixed to the tool rest 22 via a vibration transmission member 24. Therefore, the camera 23 can move in accordance with the movement of the tool rest 22. The camera 23 is positioned relative to the turning tool 21 so that the tool cutting edge is in the same position within the imaging field of view, as shown in, for example, Figures 3 to 5.

The vibration transmission member 24 connects the tool cutting edge of the turning tool 21 to the camera 23 directly or via another member. As shown in FIG. 1, in this embodiment, the vibration transmission member 24 indirectly connects the tool cutting edge to the camera 23 via a part of the turning tool 21 (holder 25) and the tool rest 22. The vibration transmission member 24 has a tip connected to the camera 23 and a rear end connected to the tool rest 22. The vibration transmission member 24 is an arm-shaped member that bends or curves. The total length of the vibration transmission member 24 is, for example, 300 mm or more.

The vibration transmission member 24 transmits the vibration of the tool cutting edge directly or indirectly via another member to the camera 23. The vibration transmission member 24 amplifies the vibration of the tool cutting edge and transmits it to the camera 23. For this reason, in this embodiment, the vibration transmission member 24 may be referred to as a vibration amplifying member 24.
In this embodiment, the term "vibration" includes, for example, vibration caused by increased cutting resistance due to damage to the tool tip, chatter vibration caused by inappropriate cutting conditions, and the like.

The vibration transmission member 24 has at least two shaft portions 24a, at least one joint portion 24b that connects the ends of adjacent shaft portions 24a, and a fixing base 24c that fixes the rear end portion of the vibration transmission member 24 to the tool rest 22.

The shaft portion 24a is, for example, a shaft or a pipe.
The joint 24b can be switched between a lock mode in which the ends of the shaft 24a are fixed so as not to rotate and a free mode in which the ends of the shaft 24a are rotatably connected to each other by operating a knob (not shown). The provision of the joint 24b allows the vibration transmission member 24 to be deformed. By changing the shape of the vibration transmission member 24, the position of the camera 23 can be adjusted so as to face the tool cutting edge. During cutting, the joint 24b is in the lock mode.

The fixed base 24c fixes the vibration transmission member 24 to the tool rest 22, for example, by magnetic force. Therefore, the mounting position of the vibration transmission member 24 can be adjusted with respect to the tool rest 22. That is, in this embodiment, the position of the camera 23 can be adjusted so that it faces the tool tip by adjusting the mounting position of the fixed base 24c to the tool rest 22.

Although not specifically shown, the chuck removably holds the workpiece W. The chuck rotates the workpiece W around its central axis O.

Although not specifically shown, the turning device 20 may also be equipped with a backlight for highlighting the contours of the cutting edge 26b and the machining surface Wa, and a frontlight for illuminating the rake face 26a. This allows the shutter speed of the camera 23 to be increased.

As shown in FIG. 2, the cutting process monitoring device 30 includes an image acquisition unit 31, a memory unit 32, a classification unit 33, an analysis unit 34, and a display unit 35. In other words, the cutting process monitoring system 10 includes a classification unit 33 and an analysis unit 34.

The image acquisition unit 31 acquires the image captured by the camera 23, i.e., image data. The image acquisition unit 31 stores the acquired image information in the storage unit 32. The cutting process monitoring device 30 may, for example, associate the acquired image information with a tool ID, a device ID, a user ID, etc., and store the information in the storage unit 32.

The memory unit 32 stores various information used by the cutting process monitoring device 30. The memory unit 32 stores acquired image information. The memory unit 32 stores, for example, deep learning teacher data and learning results used by the classification unit 33 to classify images.

The classification unit 33 performs image classification using deep learning, for example, based on the learning results stored in the memory unit 32. That is, the classification unit 33 classifies multiple images captured by the camera 23 into one of multiple patterns based on the information captured in each image. In this embodiment, the multiple patterns include a first pattern (cutting edge line), a second pattern (welding), and a third pattern (machined surface of the workpiece).

Specifically, as shown in FIG. 3, the classification unit 33 classifies an image in which the cutting edge ridge of the cutting edge 26b having a predetermined cutting edge length or more is captured within the imaging field of view into a first pattern among multiple patterns. In the example shown in FIG. 3, the cutting edge 26b is not in contact with the workpiece W, and the entire cutting edge ridge is clearly captured within the imaging field of view.

The classification unit 33 also classifies an image in which the welded TA is reflected on the tool cutting edge into a second pattern among the multiple patterns, as shown in FIG. 4. In the example shown in FIG. 4, at least a portion of the rake face 26a and at least a portion of the cutting edge 26b are hidden by the welded TA attached to the tool cutting edge.

Further, the classification unit 33 classifies the image showing the machined surface Wa of the workpiece W into a third pattern among the multiple patterns, as shown in Fig. 5. In the example shown in Fig. 5, the surface and the contour of the machined surface Wa immediately after being cut by the cutting blade 26b are clearly shown.
3 to 5 are images of the cutting edge of a tool taken when a plate-shaped workpiece W was being turned as shown in Fig. 1. The workpiece W was made of stainless steel, the rotation speed of the workpiece W was 100 revolutions per minute, and the cutting was performed in a dry environment.

The classification of images by the classification unit 33 is performed, for example, by the following method.
First, a plurality of images are taken by the camera 23 during a test cutting process performed before the main cutting process of the workpiece W. The plurality of images thus obtained are classified and stored (teacher data) into a first pattern (cutting edge ridge) in which the cutting edge 26b is not in contact with the workpiece W and the cutting edge ridge is clearly visible, a second pattern (welding) in which the cutting edge 26b is not in contact with the workpiece W but the welded TA is on the rake face 26a, and a third pattern (machined surface of the workpiece) capturing the moment when the cutting edge 26b comes into contact with the workpiece W, and the classification method is learned by deep learning. That is, machine learning is performed to estimate the classification of the first to third patterns based on the teacher data in the memory unit 32, and the learning result is fed back to the memory unit 32, thereby improving the judgment accuracy of the image classification.
It should be noted that this classification is merely an example, and the appropriate classification method varies depending on the cutting conditions, the type and shape of the workpiece W, etc.
Furthermore, automatic image recognition software such as HALCON (manufactured by Links Corporation) can be used for the classification (sorting) of the image data described above.

The analysis unit 34 analyzes the vibration state of the turning tool 21 based on the change over time of the information captured in each image captured by the camera 23. In this embodiment, the analysis unit 34 analyzes the vibration state of the tool cutting edge from the change over time of each image information classified into a first pattern (predetermined pattern) among multiple patterns. For example, an image processing program can be used as the analysis unit 34.

Specifically, the analysis unit 34 analyzes whether or not vibration has occurred based on the change in the contour length of the cutting edge ridge that appears in each image classified into the first pattern. More specifically, when vibration occurs in the turning tool 21, the positions of the cutting edge 26b that appear in each image change relative to each other, and accordingly, the cutting edge length, i.e., the contour length, of the cutting edge ridge included in the imaging field of each image also changes, and this phenomenon is utilized to perform the analysis.

Fig. 6 shows an example of image processing of the cutting edge ridge of the cutting edge 26b by the analysis unit 34. As shown in Fig. 6, in this embodiment, the analysis unit 34 detects the cutting edge ridge (edge) of the cutting edge 26b within the imaging field of view by image processing such as a canny filter, and measures the number of pixels of the edge of each image, that is, the change over time in the contour length of the cutting edge ridge (such as the width and period of increase and decrease in the number of pixels), thereby analyzing the presence or absence of vibration of the cutting edge.
In this manner, the analysis unit 34 analyzes the vibration state of the turning tool 21. Note that the above analysis is an example, and other analysis methods may be used to analyze the first pattern.

The analysis unit 34 also analyzes each image classified into the second pattern. The analysis unit 34 also analyzes each image classified into the third pattern. Explanations of the analysis contents of the second and third patterns will be omitted.

The display unit 35 displays various information of the cutting processing monitoring system 10. For example, the display unit 35 displays the analysis results of the analysis unit 34 described above.

FIG. 7 is a flowchart showing an example of the process of the cutting process monitoring device 30.
As shown in FIG. 7, first, the image acquisition unit 31 acquires image information output from the camera 23 (step S1).
Next, the classification unit 33 classifies each image into a first to third pattern based on the learning results stored in the storage unit 32 (step S2). That is, the classification unit 33 classifies each image into one of the first to third patterns by comparing the acquired image information with the learning results.

Next, the analysis unit 34 analyzes whether or not vibration occurs at the cutting edge of the tool based on the change over time of the information in each image classified into the first pattern (predetermined pattern) (step S3). That is, the analysis unit 34 performs the above-mentioned analysis using image processing based on the image information in each image classified into the first pattern (cutting edge ridge) and the change over time.
Next, the display unit 35 displays the analysis results output from the analysis unit 34 (step S4). After the process of step S4, the cutting process monitoring device 30 ends the process of the above example.

In the cutting process monitoring system 10 of this embodiment described above, the cutting edge of the tool during turning is continuously photographed by the camera 23, i.e. in real time. The multiple images acquired are then compared over time, and the magnitude and period of camera 23 shaking are stored based on changes in the image information, and the results are used to determine abnormalities in vibration during cutting. They can also be used as an index for improving cutting conditions.

According to this embodiment, the vibration of the tool cutting edge is stably transmitted to the camera 23 by the vibration transmission member 24. Therefore, the analysis unit 34 can accurately analyze in real time whether or not vibration is occurring, based on the image information captured by the camera 23.
As described above, according to this embodiment, the occurrence or non-occurrence of vibration at the cutting edge of the tool during cutting can be detected in real time.

In this embodiment, a vibration transmission member (vibration amplification member) 24 amplifies the vibration of the tool tip and transmits it to the camera 23 .
In this case, even if the vibration of the tool cutting edge is small, the vibration is amplified by the vibration transmission member 24, so that the change over time due to the occurrence of vibration appears stably in the image information captured by the camera 23. Therefore, the occurrence of vibration can be detected with higher accuracy.

In this embodiment, the analysis unit 34 analyzes the presence or absence of vibration based on a change over time in the contour length of the cutting edge ridgeline captured in each image. Specifically, the analysis unit 34 performs the above analysis using each image classified into the first pattern (predetermined pattern) by the classification unit 33.
The images continuously captured by the camera 23 during cutting include images in which the tool cutting edge is hidden by cutting chips C, images in which a large amount of welded TA has adhered and the cutting edge is difficult to see, etc. Therefore, for example, from among the many continuously captured images, images in which the outline (edge line) of the cutting edge 26b is captured for a predetermined edge length or more are classified as a predetermined pattern, and the change over time in the outline length of the edge line of each image classified into a predetermined pattern is measured, thereby making it possible to more accurately analyze whether or not vibration is occurring at the tool cutting edge.

Furthermore, in this embodiment, the classification unit 33 performs image classification using deep learning.
In this case, the accuracy of classification judgment by the classification unit 33 is stably improved by deep learning.

In this embodiment, the camera 23 captures an image of the tool cutting edge from a direction perpendicular to the rake face 26a, that is, from a direction directly facing the rake face 26a.
In this case, the camera 23 can be easily focused on the cutting edge of the tool, and the above-described effects of this embodiment can be obtained more stably.

In this embodiment, the distance between the camera 23 and the tool tip is 300 mm or more.
If the distance is 300 mm or more, for example, when replacing the cutting insert 26 with a new one or when indexing the cutting edge 26b (changing the corner used), that is, when replacing the cutting edge, the camera 23 is unlikely to get in the way of the work. Also, even if the chips C extend or scatter during cutting, they are unlikely to come into contact with the camera 23, so that effective images can be stably obtained.

In this embodiment, the overall length of the vibration transmission member 24 is 300 mm or more.
If the total length is 300 mm or more, the vibration of the tool tip is suitably amplified and easily transmitted to the camera 23 in a stable manner.

In this embodiment, the vibration transmission member 24 is deformable.
In this case, the position of the camera 23 can be adjusted so as to face the tool cutting edge by changing the shape of the vibration transmission member 24. Therefore, even if the tool shape or type of the turning tool 21 or the shape of the workpiece W is changed, for example, the tool cutting edge can be accurately photographed by the camera 23 with a simple adjustment.

In this embodiment, the vibration transmission member 24 is fixed to the tool rest 22 by magnetic force or the like so that the mounting position thereof can be adjusted.
In this case, the position of the camera 23 can be adjusted so as to face the tool cutting edge by appropriately changing the attachment position of the vibration transmission member 24 to the tool rest 22. Therefore, even if the tool shape or type of the turning tool 21 or the shape of the workpiece W is changed, for example, the tool cutting edge can be accurately photographed by the camera 23 with a simple adjustment.

Second Embodiment
Next, a cutting process monitoring system 40 according to a second embodiment of the present invention will be described with reference to Figures 2, 3, 5, and 8 to 10. In this embodiment, the same components as those in the above-mentioned embodiment are denoted by the same reference numerals, and the description thereof may be omitted.

In FIG. 2, a cutting process monitoring system 40 of this embodiment differs from the above-described embodiment at least in the analysis content of the analysis unit 34.
In this embodiment, the analysis unit 34 analyzes the vibration state of the turning tool 21 based on changes over time in information captured in each image, not only for images classified into a predetermined pattern by the classification unit 33, but for all images captured by the camera 23. For this reason, in this embodiment, the cutting process monitoring device 30 does not need to include the classification unit 33, as in the modified example of the cutting process monitoring system 40 shown in FIG.

Specifically, in this embodiment, the analysis unit 34 analyzes whether or not vibration is occurring based on a change in the position of the ridgeline of the cutting edge 26b captured in each image.
As shown in FIG. 3, the analysis unit 34 measures, for example by image processing, the distance D between one side V of the outer frame (outer edge of the imaging field of view) of each image and the cutting edge ridge of the cutting edge 26b as the number of pixels.

The graph in Figure 8 shows the change over time in the distance D obtained from each image. In Figure 8, the range of increase or decrease on the vertical axis (distance D pixel count) becomes larger than the vicinity of the symbol P on the horizontal axis (cutting time). In other words, it can be estimated that vibration occurred in the turning tool 21 from the point P in the cutting time.

Alternatively, as shown in FIG. 5, the analysis unit 34 may analyze whether or not vibration is occurring based on the change in the position of the feature point 26c of the tool cutting edge shown in each image. The analysis method based on the change in the position of the feature point 26c over time can be performed in the same manner as the analysis method based on the change in the position of the cutting edge ridge over time described above.

FIG. 9 is a flowchart showing an example of the process of the cutting process monitoring device 30 of this embodiment.
As shown in FIG. 9, first, the image acquisition unit 31 acquires image information output from the camera 23 (step S11).
Next, the analysis unit 34 analyzes whether or not vibration is occurring at the cutting edge of the tool based on the change over time of the information captured in each of the acquired images (all images) (step S12). That is, the analysis unit 34 performs the above-mentioned analysis based on each image information and its change over time using image processing.
Next, the display unit 35 displays the analysis result output from the analysis unit 34 (step S13). After the process of step S13, the cutting process monitoring device 30 ends the process of the above example.

The cutting processing monitoring system 40 of this embodiment described above provides the same effects as the previously described embodiment.

Furthermore, in this embodiment, the analysis unit 34 analyzes the presence or absence of vibration based on a change over time in the position of the cutting edge ridgeline captured in each image.
In this case, by measuring the amount of change in position of the cutting edge ridge over time and the period of change, it is possible to analyze the presence or absence of vibration of the tool cutting edge using a simpler method.

In this embodiment, the analysis unit 34 may analyze the presence or absence of vibration based on a change over time in the position of the feature point 26c of the tool cutting edge captured in each image.
In this case, too, the presence or absence of vibration of the tool cutting edge can be analyzed by a simple method. The accuracy of the analysis can be improved more stably by selecting, as the characteristic point 26c, a portion that is not easily affected by the chips C or the welded TA during cutting, that is, a portion that is not easily hidden by the chips C or the welded TA.

The present invention is not limited to the above-described embodiment, and the configuration may be modified without departing from the spirit of the present invention, for example as described below.

In the above embodiment, the vibration transmission member 24 is switchable between the lock mode and the free mode, i.e., is deformable, but this is not limiting. The vibration transmission member 24 may be configured to be non-deformable. In addition, the shape of the vibration transmission member 24 is not limited to an arm shape as long as it is capable of stably transmitting the blade vibration to the camera 23.
Furthermore, the vibration transmission member 24 may be fixed to, for example, a holder 25 instead of the tool rest 22 .

In addition, the configurations described in the above embodiments and modifications may be combined without departing from the spirit of the present invention, and additions, omissions, substitutions, and other modifications of configurations are possible. Furthermore, the present invention is not limited to the above-described embodiments, but is limited only by the claims.

The cutting process monitoring system of the present invention can detect in real time whether or not vibrations are occurring at the cutting edge of a tool during cutting. Therefore, it has industrial applicability.

10, 40... Cutting processing monitoring system, 21... Turning tool, 23... Camera, 24... Vibration transmission member (vibration amplification member), 26c... Feature points, 34... Analysis unit

Claims (5)

A camera that continuously captures the cutting edge of a turning tool during turning ;
a vibration transmission member that connects the tool blade tip and the camera directly or via another member and transmits vibration of the tool blade tip to the camera;
and an analysis unit that analyzes a vibration state of the turning tool based on a change over time in information captured in each image captured by the camera.
Cutting process monitoring system. The vibration transmission member amplifies the vibration of the tool tip and transmits the amplified vibration to the camera.
The cutting process monitoring system according to claim 1 . The analysis unit analyzes whether or not vibration is occurring based on a change in a contour length of a cutting edge ridge line shown in each of the images.
3. The cutting processing monitoring system according to claim 1 or 2. The analysis unit analyzes whether or not vibration occurs based on a change in the position of the cutting edge ridge line shown in each of the images.
The cutting process monitoring system according to any one of claims 1 to 3. The analysis unit analyzes whether or not vibration is generated based on a change in a position of a feature point of the tool tip captured in each of the images.
The cutting process monitoring system according to any one of claims 1 to 4.

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