JP7012675B2 - Machine tool imaging system and imaging method - Google Patents

Description

The present invention relates to an imaging system and an imaging method used in a computer numerically controlled (CNC) machine tool, in particular, a plurality of illuminating units for illuminating a workpiece arranged in the machine tool, and a workpiece illuminated by the illuminating unit. The present invention relates to an image pickup system including an image pickup unit for imaging an object, an illumination unit, and a control unit connected to the image pickup unit, and an image pickup method using the image pickup system.

Conventionally, a system has been known in which a camera captures the inside of a CNC machine tool and the image is displayed on a display device arranged outside the machine tool. For example, Patent Document 1 describes a machine tool provided with a cover body that separates the machined area from the outside, and the cover body has an opening for communicating the machined area and the outside through a door portion, but the outside. There is no window that allows the machined area to be visually recognized. Further, the machine tool of Patent Document 1 includes a camera that captures an image of a processing region and a display device that displays the captured image. The image captured in this way is displayed to the operator in real time via the display device, provides image data for analyzing the progress of machining by the controller, and is fed back to the control of machining by the machine tool. Therefore, in the machine tool of Patent Document 1, the clearer the image captured by the camera, the more precise the processing by the machine tool can be realized.

Generally, a machine tool is configured to cool a tool cutting edge by injecting a large amount of coolant liquid toward the cutting edge of a tool such as grinding or cutting in a machining area. As the light source, a plurality of small and highly reliable LED light sources are used. The coolant liquid sprayed toward the cutting edge collides with the workpiece and the cutting edge and scatters. That is, with the processing of the workpiece, scattered objects such as small droplets (mist-like droplets) of the coolant liquid are formed. At this time, light from a plurality of LED light sources is reflected by scattered objects, but when strong light enters an image pickup unit such as a CCD camera, a phenomenon occurs in which a part or the whole of the image becomes whitish (hereinafter, this in the present application). Such a phenomenon is called a "flare" phenomenon, or simply "flare"). In an image with flare, the contour (machining state) of the workpiece or the deposit of cutting chips generated during machining may be blurred, which may hinder the precise machining by the machine tool, so flare is eliminated. Was strongly desired.

JP-A-2017-159407

Therefore, one aspect of the present invention is to obtain a clear captured image by substantially reducing or eliminating flare in the captured image due to scattered objects generated by processing the workpiece. The purpose is to realize precise machining with machine tools.

A first aspect of the present invention relates to an image pickup system used in a machine tool, and the image pickup system is illuminated by a plurality of lighting units for illuminating a workpiece arranged in the machine tool and the lighting unit. An image pickup unit that captures an image of the work piece, a lighting unit, and a control unit connected to the image pickup unit are provided, and the control unit includes the work piece based on an image captured by the image pickup unit. The illuminating unit that illuminates the scattered matter generated by the processing of the above is specified, and the characteristics of the illuminating light from the specified illuminating unit are adjusted.

A second aspect of the present invention relates to an imaging method used in a machine tool, in which the imaging method includes a lighting step of illuminating a workpiece arranged in the machine tool using a plurality of lighting units. An imaging step of imaging the workpiece illuminated by the lighting unit using the imaging unit, and the lighting unit that illuminates scattered objects generated by processing the workpiece based on the captured image. A specific step for specifying the above and an adjustment step for adjusting the characteristics of the illumination light from the specified illumination unit are provided.

According to the aspect of the present invention, by substantially reducing or eliminating the occurrence of flare in the image due to the scattered matter generated by the processing of the workpiece, a clear captured image can be obtained and the work is performed. It is possible to realize precise processing by machine.

It is a schematic perspective view which shows the overall structure of the machine tool which concerns on Embodiment 1 of this invention. It is an enlarged perspective view which shows the schematic structure of the image pickup system which concerns on Embodiment 1. FIG. It is a block diagram which shows the schematic structure of the image pickup system which concerns on Embodiment 1. FIG. It is a top view of the image pickup system of FIG. 2 at the time of processing. It is a perspective view of the image pickup system at the time of processing of the modification 1 which concerns on Embodiment 1. FIG. It is a block diagram which shows the schematic structure of the image pickup system which concerns on Embodiment 2. It is a front view which shows the image pickup part and the illumination part of the image pickup system which concerns on Embodiment 2. FIG. It is a flowchart which shows the image pickup method of the image pickup system which concerns on Embodiment 2. It is a timing chart which shows the on / off operation of each of the plurality of lighting units of the image pickup system which concerns on Embodiment 2. FIG. It is a flowchart which shows the image pickup method which concerns on the modification 2 of Embodiment 2. It is a timing chart which shows the on-off operation of each of the plurality of illumination units of the image pickup system of the modification 2 of Embodiment 2. It is a front view which shows the image pickup part and the illumination part of the image pickup system which concerns on Embodiment 3. FIG. It is a flowchart which shows the image pickup method which concerns on Embodiment 3. It is a timing chart which shows the on / off operation of each of the plurality of lighting units of the image pickup system of Embodiment 3. It is a flowchart which shows the image pickup method which concerns on the modification 3 of Embodiment 3. It is a timing chart which shows the on-off operation of each of the plurality of illumination units of the image pickup system of the modification 3 of Embodiment 3. It is a flowchart which shows the image pickup method which concerns on Embodiment 4. It is a timing chart which shows the on / off operation of each of the plurality of lighting units of the image pickup system of Embodiment 4.

An embodiment of an imaging system and an imaging method used in the machine tool according to the present invention will be described below with reference to the accompanying drawings. In the description of each embodiment, terms indicating directions (for example, "upper and lower" and "X-axis, Y-axis, Z-axis", etc.) are appropriately used for ease of understanding, but these are for illustration purposes only. Therefore, these terms do not limit the present invention. In each drawing, in order to clarify the shape or characteristics of each component of the machine tool, these dimensions are shown as relative ones and are not necessarily expressed at the same scale ratio. Further, in each drawing, the same components are shown by using the same reference numerals.

[Embodiment 1]
The first embodiment of the image pickup system and the image pickup method according to the present invention will be described in detail below with reference to FIGS. 1 to 5. FIG. 1 is a schematic perspective view showing the overall configuration of the machine tool 100 according to each embodiment of the present invention, and FIG. 2 is an image pickup system 1 according to the first embodiment arranged inside the machine tool 100. It is a schematic perspective view which shows the component of. Further, FIG. 3 is a block diagram showing a schematic configuration of the image pickup system 1 of FIG. 2, and FIG. 4 is a plan view of the image pickup system 1 of FIG. 2 when the workpiece W is being processed.
As shown in FIG. 1, the machine tool 100 according to the first embodiment includes a machine tool chamber 101 (hereinafter, also simply referred to as “chamber”) directly installed on the floor of a factory or the like. Further, the machine tool 100 includes a bed 102 arranged in the chamber 101, a column 103 extending from the bed 102 in the Z direction (upward in FIG. 1), and a saddle extending from the column 103 in the X direction (leftward in FIG. 1). A mounting 104, a head head 105 fixed to the saddle 104, a grinding tool 21 detachably attached to the head head 105, and a workpiece W (hereinafter, also referred to as “work”) to be fixedly supported. It is equipped with a stand 106 (hereinafter, also referred to as a “table”).

The machine tool 100 according to the present invention is placed on the table 106 by attaching an arbitrary suitable machining tool such as a drilling tool (drill) or a polishing tool (grindstone, both not shown) instead of the grinding tool 21. The work W can be drilled, polished, or the like. Further, the machine tool 100 according to each embodiment preferably has a 5-axis composite capable of controlling the X-axis, the Y-axis, the Z-axis, the rotation axis, and the inclined axis to perform multi-faceted machining of the work W by one chucking. It may be a processing machine.

As shown in FIGS. 1 and 2, the workpiece W is fixed to the table 106 and has a circular convex portion T centered on the Z axis. The grinding tool 21 is attached to the spindle head 105 via the drive rod 22 and is configured to rotate around a central axis parallel to the Z axis. In the machine tool 100 of the first embodiment, the rotating grinding tool 21 comes into contact with the vertical surface (side surface along the Z-axis direction) of the convex portion T of the workpiece W, so that the convex portion T of the workpiece W is formed. It can be ground to have an arbitrary radius.

Further, while rotating the workpiece W (table 106) in the direction opposite to the rotation direction of the grinding tool 21, the grinding tool 21 is brought into contact with the vertical surface of the convex portion T of the workpiece W for grinding. May be good. In addition, the convex portion T of the workpiece W may be ground by rotating the workpiece W around the Z axis and moving the milling cutter fixed to the spindle head 105 in the vertical direction. That is, the machining method by the machine tool 100 does not limit the present invention. Similarly, the machining of the workpiece W is not limited to the simple shape described above, and the present invention is applicable to various shapes and machining realized by the 5-axis compound machining machine.

FIG. 3 is a block diagram showing a schematic configuration of the image pickup system 1 according to the first embodiment, and FIG. 4 is a plan view of the image pickup system 1 when the machine tool 100 is processing an workpiece.
As shown in FIGS. 2 to 4, the imaging system 1 according to the first embodiment generally cools the machining unit 20, the workpiece W, and the grinding tool 21 that rotationally drive the grinding tool 21 (and / or the table 106). A cooling unit 30 including a nozzle 31 that injects a large amount of coolant toward these, a workpiece W at the time of processing, a grinding tool 21, a CCD camera that captures (monitors) images of these backgrounds, and the like. 40, a plurality of lighting units 50 (illumination unit 1 and illumination unit 2) such as LEDs that illuminate the workpiece W at the time of processing, and a control unit 60 that controls the above-mentioned components. In FIG. 4, the table 106 is omitted.

During machining of the machine tool 100, the control unit 60 uses a motor (machining unit 20) arranged in the spindle head 105 to rotate the grinding tool 21 around the Z axis while forming a convex portion T of the workpiece W. Along with abutting, a large amount of coolant is sprayed from the nozzle 31 (cooling unit 30) toward the workpiece W and the grinding tool 21 to cool them. As shown by the black dots in FIG. 4, the coolant liquid ejected from the nozzle 31 collides with the workpiece W and the grinding tool 21 and scatters to form mist-like droplets (mist-like coolant C). The scattered matter generated during the processing of the workpiece is supplied to the atomized coolant C, crushed matter such as facets and cutting chips generated from the workpiece during processing, and / or the machine sliding surface. Lubricating oil, crushed material, or atomized coolant C containing lubricating oil is included, and these are collectively referred to as "scattered material" in the present application.

The image pickup unit 40 captures an image of the workpiece W at the time of processing, the grinding tool 21, and the background thereof, and the control unit 60 analyzes the image data obtained from the image pickup unit 40 and processes it by the processing unit 20. Feedback to control. The lighting unit 50 illuminates the workpiece W and the grinding tool 21 by using a light emitting diode lamp (hereinafter, simply referred to as “LED”) having a fast on / off response speed and high reliability. For example, as the grinding of the workpiece W by the grinding tool 21 progresses, the position of the grinding tool 21 approaches the Z axis, but in general, the positions of the workpiece W and the grinding tool 21 move according to the progress of the machining. Change. Therefore, the control unit 60 is configured so that the positions and pointing angles of the nozzle 31, the image pickup unit 40, and the illumination unit 50 of the cooling unit 30 can be arbitrarily adjusted according to the control procedure (control program) of the processing unit 20. There is. That is, the control unit 60 can always recognize and control the positions and directivity angles of the nozzle 31, the image pickup unit 40, and the illumination unit 50.

The mist-like coolant C shown by the black dots in FIG. 4 is a small droplet (mist-like droplet) of the coolant liquid, and is scattered radially around the grinding tool 21. The image pickup unit 40 captures these images by illuminating the small droplets of the mist-like coolant C, the workpiece W, the grinding tool 21, and the deposit of cutting chips generated during processing with the light from the illumination unit 50. do. At this time, although it depends on the positions of the small droplets of the mist-like coolant C, the image pickup unit 40, and the illumination unit 50, the light from one of the illumination units 50 (illumination unit 1 or the illumination unit 2) is the mist-like coolant. Reflected by the small droplets of C, strong light may partially enter the image pickup unit 40, causing flare that makes a part or the whole of the image whitish. In the flared image, the contour (machined state) of the workpiece W or the deposit of cutting chips generated during machining is blurred.

Therefore, the control unit 60 according to the first embodiment identifies the position of a small drop of the mist-like coolant C that causes flare and causes the flare so that the image captured by the image pickup unit 40 does not cause flare. The unit 50 (illumination unit 1 or illumination unit 2) is configured to reduce the light (reduce the light intensity from the illumination unit 50) or turn it off. In the present application, for convenience, the mist-like coolant C that causes flare is referred to as "flare coolant FC", and the lighting unit that causes flare is referred to as "flare lighting unit 50".

Specifically, first, the control unit 60 determines whether or not flare has occurred in the captured image. As described above, the control unit 60 constantly recognizes and controls the positions and directivity angles of the image pickup unit 40 and the illumination unit 50, but based on the flared image, the image pickup unit 40 to the flare coolant FC. The distance d and the inclination angle θ with respect to the central axis of the imaging unit 40 are obtained. The image pickup unit 40 may include a Time of Flight (ToF) sensor. The control unit 60 can determine, for example, that the flare illumination unit is the “illumination unit 1” from the distance d to the flare coolant FC and the inclination angle θ. Further, the control unit 60 reduces or turns off the lighting unit 1 for a certain period of time, illuminates the workpiece W and the grinding tool 21 using only the lighting unit 2, and controls to obtain these images. In this way, the control unit 60 according to the first embodiment obtains a clear image showing the outline (machining state) of the workpiece W or the deposit of cutting chips generated during machining, and realizes precise machining by the machining section 20. can do.

Although not shown in detail, the control unit 60 has an artificial intelligence (AI) function, includes a distance d to the flare qualant FC, an inclination angle θ, a constituent material of the workpiece W, and a type of grinding tool 21. , The constituent material of the coolant, the ejection speed of the coolant ejected from the nozzle 31, and the wavelength of the illumination light from the illumination unit 50 as parameters, which are associated with the captured image, and the weighting coefficient learned in the neural network such as deep learning. Machine learning may be performed so as to perform an operation based on the response function and derive the position / angle of the flare coolant FC and the flare illumination unit 50.

In this way, the control unit 60 determines that flare has occurred based on the image captured by the image pickup unit 40, derives the position / angle of the flare coolant FC, and reduces the flare illumination unit for a certain lighting period. By turning the light on or off, it is possible to capture an image in which flare does not occur. As a result, the control unit 60 can obtain a clear image showing the contour (machining state) of the workpiece W or the deposit of cutting chips generated during machining, and can realize precise machining by the machining section 20. can. Further, the control unit 60 may be configured to periodically determine whether or not flare has occurred in the captured image after a certain lighting period has elapsed.

The workpiece W of the first embodiment is fixed to the table 106 and has a circular convex portion T centered on the Z axis. However, the present invention describes the embodiment and processing of the workpiece W. It is not limited to the type of the processing tool 21 of the unit 20, and is widely adopted in the image pickup system of the machine tool 100 that processes the workpiece W and the grinding tool 21 while injecting the coolant liquid using the cooling unit 30. be able to.

(Modification 1)
FIG. 5 is a perspective view of the imaging system 1 according to the first modification of the first embodiment. In the image pickup system 1 of FIG. 5, the workpiece W is attached to the side chuck 23, a polishing tool (machining portion 20) such as a grindstone is connected to the spindle 24 rotating around the X axis, and the nozzle 31 for injecting coolant. (Cooling unit 30) is attached to the side turret 25. Further, as in the first embodiment, the image pickup system 1 is configured to illuminate the workpiece W and the machined portion 20 with two lighting units 50 and to capture these images using the image pickup unit 40.

In the image pickup system shown in FIG. 5, the control unit 60 similarly determines whether or not flare has occurred in the captured image, and based on the flared image, the distance d from the image pickup unit 40 to the flare coolant FC. , The inclination angle θ with respect to the central axis of the image pickup unit 40 is obtained. Then, the control unit 60 determines from the distance d and the inclination angle θ that, for example, the flare lighting unit is the lighting unit 1, then turns off or turns off the lighting unit 1 for a certain period of time, and covers the lighting unit 1 using only the lighting unit 2. The workpiece W and the grinding tool 21 are illuminated and controlled to obtain these images.

In this way, the control unit 60 determines that flare has occurred based on the image captured by the image pickup unit 40, derives the position / angle of the flare coolant FC, and keeps the lighting constant, as in the first embodiment. By reducing or extinguishing the flare illumination unit during the period, it is possible to capture an image in which flare does not occur. In this way, the control unit 60 can obtain a clear image showing the contour (machining state) of the workpiece W or the deposit of cutting chips generated during machining, and can realize precise machining by the machining section 20.

[Embodiment 2]
The second embodiment of the imaging system and the imaging method according to the present invention will be described in detail below with reference to FIGS. 6 to 9. Since the imaging system of the second embodiment has the same configuration as the imaging system (two) of the first embodiment except that it includes 10 lighting units 50, the description of the overlapping points will be omitted.

FIG. 6 is a block diagram showing a schematic configuration of the image pickup system 2 according to the second embodiment, and FIG. 7 is a front view showing an image pickup unit 40 and a plurality of illumination units 50 of the image pickup system 2 according to the second embodiment. be. As described above, the image pickup system 2 according to the second embodiment has 10 illumination units 50 (illumination units 1 to 10 in FIG. 6), and as shown in FIG. 7, the image pickup unit 40 arranged in the center. Illumination units 50 are arranged around the lighting units at equal intervals. In FIG. 7, the illumination units 50 are arranged concentrically with the image pickup unit 40 at intervals of 36 degrees, but the present invention is not limited to this configuration, and any shape such as an ellipse or a rectangle can be used. It may be arranged at intervals, or the image pickup unit 40 and each illumination unit 50 may be configured as separate bodies. Further, the image pickup system 2 of FIG. 6 can be rotated around an arbitrary orthogonal rotation axis as shown by a rotation arrow, and the control unit 60 is directed toward the processing unit 20 for processing the workpiece W. The image pickup unit 40 and each illumination unit 50 can be directed in any direction.

The control unit 60 can turn on or off (reduce) each of the illumination units 50 (illumination units 1 to 10) independently of each other. The image pickup unit 40 preferably employs a CCD camera capable of capturing images of the workpiece W and the processing unit 20 in a short frame unit period and transmitting image data to the control unit 60 in real time, for example, in a frame unit period. Is 1 ms. The frame unit period may be the minimum time of an image frame that the image pickup unit 40 can continuously image. Further, as in the first embodiment, each lighting unit 50 preferably uses an LED having a fast on / off response speed and high reliability, and can be operated on / off at an equivalent response speed (for example, 1 ms) in a frame unit period. ..

FIG. 8 is a flowchart showing control (imaging method) of the imaging system 2 according to the second embodiment, and FIG. 9 is a timing chart showing an on / off operation of a plurality of lighting units of the imaging system 2 according to the second embodiment. .. The imaging method according to the second embodiment will be described in detail below with reference to FIGS. 8 and 9. In order to make the present invention easier to understand, each lighting unit 50 is referred to as "LED 1 to 10", the image pickup unit 40 is simply referred to as a camera 40, and the workpiece W and the grinding tool imaged by the camera 40 are referred to. 21 and images of these backgrounds are referred to as "camera images".

According to the image pickup method according to the second embodiment, in step ST01, in step ST01, all the LEDs 1 to 10 are turned on for a predetermined full lighting period (for example, 10 ms) corresponding to 10 times the frame unit period, and the camera 40 is turned on. Controls to capture a camera image, and stores image data related to each camera image corresponding to each frame unit period or a camera image as an average value thereof in a memory (not shown) in the control unit 60. At this time, it is assumed that flare has occurred in the camera image captured during the entire lighting period. When no flare has occurred in the camera image, although not shown in detail, the control unit 60 returns to ST01 and lights LEDs 1 to 10 during the entire lighting period. That is, according to the imaging method according to this embodiment, as long as flare does not occur in the camera image, all the LEDs 1 to 10 are continuously turned on to capture the camera image as in the normal imaging method. The total lighting period may be set longer or shorter than 10 ms.

In step ST02, the control unit 60 sets the variable i to 1. In step ST03, after the end of all lighting periods, the control unit 60 turns off only the LEDi for a frame unit period (for example, 1 ms) (OFF), and in step ST04, determines whether or not flare has disappeared from the camera image. In step ST05, the control unit 60 stores the LEDi turned off when the flare disappears from the camera image in a memory (not shown) in the control unit 60. In step ST06, the control unit 60 increments the variable i and repeats steps ST03 to ST06.

In step ST07, the control unit 60 proceeds to step ST08 when the variable i exceeds 10 (i = 11), and turns off each LED other than the LEDi (for example, LED5 in FIG. 9) when the flare disappears. A camera image is obtained by turning on the light for a predetermined lighting period (for example, 80 ms). At this time, the control unit 60 may reduce the light (reduce the light intensity from the LEDi) at a constant rate instead of completely turning off the LEDi that was turned off when the flare disappeared during the lighting period. The light may be dimmed according to the degree of flare given to the image.

In step ST09, the control unit 60 obtains a camera image in which flare is eliminated or substantially reduced, and a clear camera showing the contour (machining state) of the workpiece W or the deposit of cutting chips generated during machining. By analyzing the image, precise processing by the processing unit 20 can be realized. After step ST09, the control unit 60 returns to step ST01 again to repeatedly perform the operations of ST01 to 09, continuously obtain a clear camera image, and perform accurate processing using the processing unit 20. ..

(Modification 2)
The second modification of the second embodiment will be described below with reference to FIGS. 10 and 11. The imaging method of the second modification is substantially the same as the imaging method of the second embodiment, except that the LEDs 1 to 10 are turned on in sequence to determine whether or not flare occurs in the camera image. The description of the overlapping points will be omitted.
FIG. 10 is a flowchart showing the imaging method according to the modified example 2, and FIG. 11 is a timing chart showing an on / off operation of a plurality of lighting units of the imaging system 2 according to the modified example 2. The imaging method according to the second modification will be described below with reference to FIGS. 10 and 11.

According to the imaging method according to the second modification, the control unit 60 sets the variable i to 1 in step ST11, and then turns on the LEDi for a frame unit period (for example, 1 ms) in step ST12 (ON). ), It is determined in step ST13 whether or not flare has occurred in the camera image. Further, in step ST14, the control unit 60 stores the LEDi lit when flare occurs in the camera image in a memory (not shown) in the control unit 60. In step ST15, the control unit 60 increments the variable i and repeats steps ST12 to ST15.

In step ST16, when the variable i exceeds 10 (i = 11), the control unit 60 proceeds to step ST17 and turns on each LED other than the LEDi (for example, LED5 in FIG. 11) that is turned on when flare occurs. A camera image is obtained by turning on the light for a predetermined lighting period (for example, 90 ms). At this time, as in the second embodiment, the control unit 60 according to the second modification does not completely turn off the LEDi that was turned on when flare occurs during the lighting period, but reduces the light at a constant rate (from the LEDi). The light intensity may be reduced), or the light may be reduced according to the degree of flare given to the camera image.

In step ST18, the control unit 60 obtains a camera image in which flare is eliminated or substantially reduced, and a clear camera showing the contour (machining state) of the workpiece W or the deposit of cutting chips generated during machining. By analyzing the image, precise processing by the processing unit 20 can be realized. After step ST18, the control unit 60 returns to step ST11 again to repeatedly perform the operations of ST11 to 18, continuously obtain a clear camera image, and perform accurate processing using the processing unit 20. ..

[Embodiment 3]
The third embodiment of the imaging system and the imaging method according to the present invention will be described in detail below with reference to FIGS. 12 to 14. The image pickup system 3 of the third embodiment includes five illumination units 50, and each illumination unit 50 has two LEDs (for example, an infrared LED and a white LED) having different peak wavelengths from each other. Since it has the same configuration as the image pickup system 2 (single color) of the above, the description of the overlapping points will be omitted.

FIG. 12 is a front view showing an image pickup unit 40 and a plurality of illumination units 50 of the image pickup system 3 according to the third embodiment. As shown in the figure, the image pickup system 3 has five illumination units 50 (see FIG. 12) around an image pickup unit 40 arranged in the center, and each illumination unit 50 has, for example, an infrared LED chip (LED /). It has an IR) and a white LED chip (LED / W). In FIG. 12, the infrared LED and the white LED of each lighting unit 50 are referred to as “50IR” and “50W”, respectively.

The imaging unit 40 of the third embodiment is a CMOS sensor capable of imaging the imaging wavelength from the visible band to the infrared band, or a visible light sensor capable of imaging in the visible band and an infrared sensor capable of imaging in the infrared band. Be prepared. The white LED chip may be one in which a phosphor is arranged around an ultraviolet LED or a blue LED chip, or may be a combination of blue, green, and red LED chips.

By the way, the coolant liquid is composed of various components such as water, polyethylene glycol, polypropylene glycol, and a water-soluble processing oil (lubricating oil), and each of the above components has a high absorption coefficient at a specific infrared peak wavelength. .. For example, water has a high absorption coefficient at an absorption wavelength of 1450 nm, polyethylene glycol at 1452 nm, and polypropylene glycol at an absorption wavelength of 1427 nm (more likely to absorb light).

Therefore, by adopting an infrared LED chip of each lighting unit 50 of the third embodiment having a peak wavelength of, for example, around 1450 nm, the control unit 60 is a camera when illuminated with infrared light from the infrared LED chip. As in the first embodiment, the position / angle of each droplet of the coolant can be monitored based on the image (hereinafter referred to as “infrared camera image”). In the present application, the light selectively absorbed by the coolant (scattered matter) (light having a high absorption coefficient at a specific absorption wavelength, for example, infrared light) is referred to as "first spectral light" and is not selectively absorbed. White light is also referred to as "second spectral light".

Further, the control unit 60 determines whether or not flare has occurred in the infrared camera image and the camera image illuminated by the white light from the white LED chip (hereinafter referred to as “white camera image”) as in the above embodiment. By making a determination, the position / angle of the scattered matter that causes flare and the flare illumination unit 50 can be specified.

Further, the control unit 60 can distinguish between the flare caused by the pulverized material generated during processing and the flare caused by the atomized coolant C by comparing the white camera image and the infrared camera image. That is, even if flare is generated due to the workpiece W and the background object such as the grinding tool 21, the control unit 60 allows the flare, and only when the flare coolant FC is detected, the flare illumination is performed. The unit 50 may be turned off or turned off. In this way, according to the imaging method according to the third embodiment, it is possible to eliminate or reduce only the flare caused by the flare-coolant FC, continuously analyze a clear camera image, and realize accurate processing.

Alternatively, the control unit 60 may be configured to more reliably identify the flare coolant FC by providing an artificial intelligence (AI) function, as described above in Embodiment 1. Specifically, the control unit 60 compares the captured infrared camera image with the white camera image, and determines the distance d to the flare coolant FC and the inclination angle θ when flare caused by the atomized coolant C occurs. After accumulating the above parameters as big data (after obtaining the trained weighting coefficient and response function), the distance d to the flare qualant FC and the tilt angle θ that will occur in the white camera image are shown in the infrared camera image. Predict only from. Then, the control unit 60 illuminates with each infrared LED chip for a shorter detection period (for example, 5 ms = 1 ms × 5) to obtain an infrared camera image, whereby the flare coolant FC and the flare illumination unit are similarly to the first embodiment. 50 may be derived (not shown). In this way, the control unit 60 more quickly and surely identifies the flare coolant FC, turns off or dims the flare illumination unit 50, eliminates or reduces only the flare caused by the flare coolant FC, and continuously clears the camera image. Therefore, accurate processing can be performed using the processing unit 20.

The imaging method according to the third embodiment described above will be described in detail below with reference to FIGS. 13 and 14. FIG. 13 is a flowchart showing an imaging method of the imaging system 3 according to the third embodiment, and FIG. 14 is a timing chart showing an on / off operation of a plurality of lighting units of the imaging system 3 according to the third embodiment. The image pickup system 3 according to the third embodiment includes an infrared LED chip (LED1 to 5 / IR) and a white LED chip (LED1 to 5 / W) as an illumination unit 50.

According to the image pickup method according to the third embodiment, in step ST21, the control unit 60 includes all infrared LED chips (LED1 to 5 / IR) and white LED chips (LED1) in a predetermined full lighting period (for example, 10 ms). ~ 5 / W) lights up alternately, and the image pickup unit 40 controls to capture the infrared camera image and the white camera image, and the memory (not shown) in the control unit 60 corresponds to each frame unit period. Stores image data related to each camera image or a camera image as an average value thereof. At this time, it is assumed that flare has occurred at least in the white camera image (and the infrared camera image). If flare does not occur in the white camera image, although not shown in detail, the process returns to ST21 to turn on LEDs 1 to 5 / IR and LEDs 1 to 5 / W for the entire lighting period. That is, according to this imaging method, all LEDs 1 to 5 / IR and LEDs 1 to 5 / W are continuously used as in the general imaging method, as long as flare does not occur at least in the white camera image (and infrared camera image). Turn on and take an infrared camera image and a white camera image. The control unit 60 can specify the position / angle / distribution state of each droplet of the coolant liquid from the infrared camera images of LEDs 1 to 5 / IR. The total lighting period may be set longer or shorter than 10 ms.

In step ST22, the control unit 60 sets the variable i to 1. In step ST23, after the end of the entire lighting period, the control unit 60 turns off the LEDi / IR and LEDi / W for each frame unit period (for example, 1 ms) (OFF), and in step ST24, the flare disappears from the white camera image. Whether or not, that is, whether or not flare coolant FC is detected is determined. In this way, the control unit 60 identifies the position / angle of the scattered object or the background object that causes flare from the white camera image of the LEDs 1 to 5 / W, and each of the coolant liquids obtained from the infrared camera image. By comparing with the position / angle of the droplet, it is determined whether or not the flare-coolant FC that causes flare is detected.

In step ST25, the control unit 60 stores the LEDi / IR and the LEDi / W turned off when the flare disappears from the white camera image in a memory (not shown) in the control unit 60. In step ST26, the control unit 60 increments the variable i and repeats steps ST23 to ST25.

In step ST27, the control unit 60 proceeds to step ST28 when the variable i exceeds 5, and turns off the LEDi / IR and LEDi / W (for example, LED3 in FIG. 14) when the flare disappears. Each LED other than / IR and LED3 / W) is turned on for a predetermined illumination period (for example, 80 ms) to obtain an infrared camera image and a white camera image. At this time, the control unit 60 does not completely turn off the LEDi / IR and LEDi / W that were turned off when the flare disappeared during the lighting period, but reduced the light at a constant rate (reduces the light intensity from the LEDi). ), Or the light may be dimmed according to the degree of flare given to the camera image.

In step ST29, the control unit 60 obtains a camera image in which the coolant flare is eliminated or substantially reduced, and clearly shows the contour (machining state) of the workpiece W or the deposit of cutting chips generated during machining. By analyzing the camera image, precise processing by the processing unit 20 can be realized. After step ST29, the control unit 60 returns to step ST21 again to repeatedly perform the operations of ST21 to 29, continuously obtain a clear camera image, and perform accurate processing using the processing unit 20. ..

(Modification 3)
A modified example 3 of the third embodiment will be described below with reference to FIGS. 15 and 16. The imaging method of the third modification is generally except that each LEDi / IR and LEDi / W are turned on in sequence to determine at least whether or not coolant flare occurs in a white camera image (and an infrared camera image). Since it is the same as the imaging method of the third embodiment and corresponds to the second modification with respect to the second embodiment, the description of the overlapping points will be omitted.

FIG. 15 is a flowchart showing the imaging method according to the modified example 3, and FIG. 16 is a timing chart showing the on / off operation of a plurality of lighting units of the imaging system 3 according to the modified example 3. The imaging method according to the modified example 3 will be described below with reference to FIGS. 15 and 16.
According to the imaging method according to the third modification, the control unit 60 sets the variable i to 1 in step ST31, and then sets the LEDi / IR and LEDi / W in the frame unit period (for example, 1 ms) in step ST32. ) Turn on (ON), and determine whether or not flare has occurred in at least the white camera image (and the infrared camera image) in step ST33. Further, in step ST34, the control unit 60 stores the LEDi / IR and LEDi / W lit at least when flare occurs in the white camera image (and infrared camera image) in the memory (not shown) in the control unit 60. Remember in. In step ST35, the control unit 60 increments the variable i and repeats steps ST32 to ST35.

In step ST36, the control unit 60 proceeds to step ST37 when the variable i exceeds 5, and turns on the LEDi / IR and LEDi / W (for example, the LED 3 in FIG. 16) when flare occurs. Each LED other than / IR and LED3 / W) is turned on for a predetermined illumination period (for example, 90 ms) to obtain an infrared camera image and a white camera image. At this time, as in the third embodiment, the control unit 60 does not completely turn off the LEDsi / IR and LEDi / W that were turned on when flare occurs during the lighting period, but reduces the lights at a constant rate (from LEDi). The light intensity may be reduced), or the light may be reduced according to the degree of flare given to the camera image.

In step ST38, the control unit 60 obtains a camera image in which the coolant flare is eliminated or substantially reduced, and clearly shows the contour (machining state) of the workpiece W or the deposit of cutting chips generated during machining. By analyzing the camera image, precise processing by the processing unit 20 can be realized. After step ST38, the control unit 60 returns to step ST31 again to repeatedly perform the operations of ST31 to 38, continuously obtain a clear camera image, and perform accurate processing using the processing unit 20. ..

[Embodiment 4]
Embodiment 4 of the imaging system and imaging method according to the present invention will be described in detail below with reference to FIGS. 17 and 18. The image pickup system 4 of the fourth embodiment includes five illumination units 50, except that each illumination unit 50 has two LEDs (eg, blue LED / B and red LED / R) having different peak wavelengths from each other. Since it has the same configuration as the image pickup system 3 (infrared LED / IR and white LED / W) of the third embodiment, the description of overlapping points will be omitted.

By the way, the coolant liquid is a mist-like droplet (small droplet of the coolant liquid) formed by colliding / scattering with the workpiece W and the grinding tool 21, and is composed of spherical small droplets having a constant diameter. In many cases. In general, the smaller the diameter of a spherical droplet, the easier it is to scatter light with a longer wavelength, and the easier it is to selectively reflect light with a shorter wavelength (high reflectance). In the present application, the light selectively reflected by the coolant (scattered matter) (light having a specific reflection wavelength, for example, blue light) is referred to as "third spectral light", and light that is not selectively absorbed (for example, red). Light) is also referred to as "fourth spectral light".

Therefore, in the image pickup system and the image pickup method according to the fourth embodiment, it is assumed that the droplets of the coolant have a specific particle size, and the camera image obtained by illuminating the blue light from the blue LED of the illumination unit 50 ( Hereinafter, the camera image obtained by illuminating the red light from the red LED of the lighting unit 50 (hereinafter referred to as “red camera image”) is compared with the “blue camera image”) of both. It is determined that the part of the image where the difference is significant is caused by the coolant droplets. In this way, the control unit 60 according to the fourth embodiment can monitor the position / angle of each droplet of the coolant liquid from the blue camera image and the red camera image as in the third embodiment.

Further, the control unit 60 can identify the flare coolant FC and the flare illumination unit 50 that cause flare by determining whether or not flare has occurred in the blue camera image and the red camera image. Further, since the reflection intensity of the workpiece W and the background object such as the grinding tool 21 does not increase or decrease depending on the wavelength of the light from the illumination unit 50, flare caused by the background object may occur. However, this is allowed, and the flare illumination unit 50 can be turned off or turned off only when the flare qualant FC is detected. In this way, according to the imaging method according to the fourth embodiment, it is possible to eliminate or reduce only the flare caused by the flare-coolant FC, continuously analyze a clear camera image, and realize accurate processing.

The imaging method according to the fourth embodiment described above will be described in detail below with reference to FIGS. 17 and 18. FIG. 17 is a flowchart showing an imaging method of the imaging system 4 according to the fourth embodiment, and FIG. 18 is a timing chart showing an on / off operation of a plurality of lighting units of the imaging system 4 according to the fourth embodiment. The image pickup system 4 according to the fourth embodiment includes a blue LED chip (LEDs 1 to 5 / B) and a red LED chip (LEDs 1 to 5 / R) as an illumination unit 50.

According to the imaging method according to the fourth embodiment, in step ST41, the control unit 60 performs all the red LED chips (LEDs 1 to 5 / R) and the blue LED chips (LEDs 1 to 5 / B) during the entire lighting period (for example, 10 ms). ) Are alternately lit, and the image pickup unit 40 is controlled to capture the red camera image and the blue camera image. Further, the control unit 60 stores image data related to each camera image corresponding to each frame unit period or a camera image as an average value thereof in the internal memory. At this time, it is assumed that flare has occurred at least in the red camera image (and the blue camera image). If no flare has occurred in the red camera image, although not shown in detail, the process returns to ST41 to turn on LEDs 1 to 5 / R and LEDs 1 to 5 / B during the entire lighting period. That is, according to this imaging method, all LEDs 1 to 5 / R and LEDs 1 to 5 / B are continuously turned on as in the general imaging method, unless flare occurs at least in the red camera image (and the blue camera image). Then, the red camera image and the blue camera image are taken. The control unit 60 can specify the position / angle / distribution state of each droplet of the coolant liquid from the blue camera image and the red camera image.

In step ST42, the control unit 60 sets the variable i to 1. In step ST43, after the end of the entire lighting period, the control unit 60 turns off the LEDi / R and LEDi / B for each frame unit period (for example, 1 ms) (OFF), and in step ST44, the flare disappears from the red camera image. It is determined whether or not the flare-coolant FC is detected. That is, the control unit 60 identifies the position / angle of the scattered object or the background object that causes flare from the red camera image of the LEDs 1 to 5 / R, and each small drop of the coolant liquid obtained from the blue camera image. By comparing with the position / angle, it is determined whether or not the flare coolant FC that causes flare is detected.

In step ST45, the control unit 60 stores the LEDsi / R and the LEDsi / B turned off when the flare disappears from the red camera image in a memory (not shown) in the control unit 60. In step ST46, the control unit 60 increments the variable i and repeats steps ST43 to ST47.

In step ST47, the control unit 60 proceeds to step ST48 when the variable i exceeds 5, and turns off the LEDs i / R and LEDi / B (for example, LED 3 in FIG. 18) when the flare disappears. Each LED other than / R and LED3 / B) is turned on for a predetermined lighting period (for example, 80 ms) to obtain a red camera image and a blue camera image. At this time, the control unit 60 does not completely turn off the LEDi / R and LEDi / B that were turned off when the flare disappeared during the lighting period, but reduced the light at a constant rate (reduces the light intensity from the LEDi). ), Or the light may be dimmed according to the degree of flare given to the camera image.

In step ST49, the control unit 60 obtains a camera image in which the coolant flare is eliminated or substantially reduced, and clearly shows the contour (machining state) of the workpiece W or the deposit of cutting chips generated during machining. By analyzing the camera image, precise processing by the processing unit 20 can be realized. After step ST49, the control unit 60 returns to step ST41 again to repeatedly perform the operations of ST41 to 49, continuously obtain a clear camera image, and perform accurate processing using the processing unit 20. ..

Although not shown in detail, in the fourth embodiment, the control unit 60 determines whether or not coolant flare occurs by turning off the LEDs i / R and the LEDs i / B in sequence. Similar to the imaging method of the third modification of the third embodiment, the LEDs i / R and the LEDs i / B may be turned on in sequence to determine whether or not coolant flare occurs.

Further, in the above embodiment 4, a red LED chip (LED1 to 5 / R) is used to detect the flare qualant FC, but a white LED chip (LED1 to 5 / W) using a phosphor can also be used. Alternatively, a green LED chip (LED1 to 5 / G) may be added to each lighting unit 50, and a three-primary color LED chip (LED1 to 5 / RGB) may be used. That is, when it is determined that the coolant flare has occurred, the control unit 60 adjusts the light intensity (color tone of the lighting unit 50) of each LEDi / RGB of the lighting unit 50 which is turned off when the flare disappears during the lighting period. May be good.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

The present invention can be used in an imaging system and an imaging method used in a computer numerically controlled machine tool.

1-4 ... Imaging system, 20 ... Machining unit, 21 ... Machining tool, 22 ... Drive rod, 23 ... Side chuck, 24 ... Spindle, 25 ... Turret, 31 ... Nozzle, 30 ... Cooling unit, 40 ... Imaging unit, 50 ... lighting unit, 60 ... control unit, 100 ... machine tool, 101 ... machine tool chamber, 102 ... bed, 103 ... column, 104 ... saddle, 105 ... spindle head, 106 ... mounting table (table), W ... machined Object, T ... convex part of work piece, C ... atomized coolant, FC ... flare coolant

Claims (12)

Multiple lighting units that illuminate the workpiece placed in the machine tool,
An image pickup unit that captures an image of the workpiece illuminated by the illumination unit,
A control unit connected to the illumination unit and the image pickup unit is provided.
When a flare occurs in an image captured by the image pickup unit, the control unit illuminates scattered objects generated by processing the workpiece based on the position of the flare with respect to the image pickup unit and the illumination unit. An imaging system for a machine tool that identifies the lighting unit that forms the flare , turns off the identified lighting unit, or reduces the intensity of the illumination light from the lighting unit . Multiple lighting units that illuminate the workpiece placed in the machine tool,
An image pickup unit that captures an image of the workpiece illuminated by the illumination unit,
A control unit connected to the illumination unit and the image pickup unit is provided.
The control unit controls to illuminate each of the plurality of illumination units and then turn them off in sequence, and identifies the illumination unit when the flare disappears from the image captured by the image pickup unit. The illuminating unit that illuminates the scattered material generated by the processing of the workpiece and forms the flare is specified, and the identified illuminating unit is turned off or the illumination light from the illuminating unit is turned off. An imaging system for machine tools that reduces strength . Multiple lighting units that illuminate the workpiece placed in the machine tool,
An image pickup unit that captures an image of the workpiece illuminated by the illumination unit,
A control unit connected to the illumination unit and the image pickup unit is provided.
The control unit controls each of the plurality of illumination units to be sequentially illuminated, and by specifying the illumination unit when flare occurs in the image captured by the image pickup unit, the workpiece is processed. The illumination unit that forms the flare while illuminating the scattered matter generated by the processing of the above is specified, and the identified illumination unit is turned off or the intensity of the illumination light from the illumination unit is reduced . Imaging system for machine tools. The control unit identifies the lighting unit within the detection period, and turns off the lighting unit or reduces the intensity of the illumination light from the lighting unit in a lighting period longer than the detection period. The imaging system for a machine tool according to any one of claims 1 to 3, wherein the image pickup system of the machine tool is repeated. A first spectral light including an absorption wavelength that is selectively absorbed by scattered objects generated by processing the workpiece, which is a plurality of illuminating units that illuminate the workpiece arranged in the machine tool. A plurality of illuminating units that switchably illuminate a second spectral light including a non-absorbing wavelength different from the absorption wavelength, and
An image pickup unit that captures an image of the workpiece illuminated by the illumination unit,
A control unit connected to the illumination unit and the image pickup unit is provided.
Based on the image captured by the image pickup unit, the control unit identifies the illumination unit that illuminates the scattered object and forms a flare, and turns off or dims the identified illumination unit. ,
The control unit controls each of the plurality of illumination units to be sequentially illuminated with the first spectral light and the second spectral light, and takes an image when the first spectral light is irradiated. By comparing the first spectral image with the second spectral image captured when the second spectral light is irradiated, the position of the scattered matter and the first spectrum image identified from the first spectral image. By comparing with the position of the flare specified from the spectral image of 2, the illuminating unit corresponding to the first and second spectral images in which both positions match is illuminated with the scattered matter and the flare. An imaging system for a machine tool specified as the lighting unit to be formed . A third spectral light including a reflection wavelength that is selectively reflected by scattered objects generated by processing the workpiece, which is a plurality of illuminating units that illuminate the workpiece arranged in the machine tool. A plurality of illuminating units that switchably illuminate a fourth spectral light including a non-reflective wavelength different from the reflected wavelength, and
An image pickup unit that captures an image of the workpiece illuminated by the illumination unit,
A control unit connected to the illumination unit and the image pickup unit is provided.
Based on the image captured by the image pickup unit, the control unit identifies the illumination unit that illuminates the scattered object and forms a flare, and turns off or dims the identified illumination unit. ,
The control unit controls each of the plurality of illumination units to be sequentially illuminated with the third spectral light and the fourth spectral light, and takes an image when the third spectral light is irradiated. By comparing the third spectral image with the fourth spectral image captured when the fourth spectral light is irradiated, the position of the scattered matter and the second spectrum image identified from the third spectral image. By comparing with the position of the flare specified from the spectral image of 4, the illuminating unit corresponding to the third and fourth spectral images in which both positions match is illuminated with the scattered matter and the flare. An imaging system for a machine tool specified as the lighting unit to be formed . A lighting process that illuminates a workpiece placed in a machine tool using multiple lighting units,
An imaging step of imaging the workpiece illuminated by the lighting unit using the imaging unit, and
When flare occurs in the captured image, the illumination that forms the flare while illuminating the scattered matter generated by the processing of the workpiece based on the position of the flare with respect to the image pickup unit and the illumination unit. A specific process to identify the part and
A method for imaging a machine tool, comprising an adjustment step of turning off the specified lighting unit or reducing the intensity of illumination light from the lighting unit . A lighting process in which a plurality of lighting units are used to illuminate an workpiece arranged in a machine tool, and a lighting process in which each of the plurality of lighting units is illuminated and then turned off in sequence. ,
An imaging step of imaging the workpiece illuminated by the lighting unit using the imaging unit, and
By specifying the illuminating unit when the flare disappears from the image captured by the imaging unit, the illuminating unit that illuminates the scattered matter generated by the processing of the workpiece and specifies the illuminating unit that forms the flare. Specific process to be performed and
A method for imaging a machine tool, comprising an adjustment step of turning off the specified lighting unit or reducing the intensity of illumination light from the lighting unit . A lighting process for illuminating a workpiece arranged in a machine tool using a plurality of lighting units, and a lighting process for controlling each of the plurality of lighting units to be sequentially illuminated .
An imaging step of imaging the workpiece illuminated by the lighting unit using the imaging unit, and
By specifying the illuminating unit when flare occurs in the image captured by the imaging unit, the illuminating unit that illuminates the scattered matter generated by the processing of the workpiece and specifies the illuminating unit that forms the flare. Specific process to be performed and
A method for imaging a machine tool, comprising an adjustment step of turning off the specified lighting unit or reducing the intensity of illumination light from the lighting unit . The image pickup method for a machine tool according to any one of claims 7 to 9, wherein the specific step is executed within the detection period and the adjustment step is executed over a lighting period longer than the detection period. A lighting process that illuminates a workpiece placed in a machine tool using multiple lighting units,
An imaging step of imaging the workpiece illuminated by the lighting unit using the imaging unit, and
Based on the captured image, a specific step of illuminating the scattered matter generated by the processing of the workpiece and specifying the illuminating portion that forms a flare, and a specific step.
It is provided with an adjustment step of turning off or dimming the specified lighting unit .
The illuminating unit illuminates the first spectral light including an absorption wavelength selectively absorbed by the scattered matter and the second spectral light including a non-absorbing wavelength different from the absorption wavelength so as to be switchable.
In the lighting step, each of the plurality of lighting units is controlled to be sequentially illuminated by the first spectral light and the second spectral light.
In the specific step, the first spectral image captured when the first spectral light is irradiated is compared with the second spectral image captured when the second spectral light is irradiated. The first and second spectral images in which both positions match by comparing the position of the scattered object identified from the first spectral image with the position of the flare identified from the second spectral image. A method of imaging a machine tool , wherein the illumination unit corresponding to the above is specified as the illumination unit that illuminates the scattered object and forms the flare . A lighting process that illuminates a workpiece placed in a machine tool using multiple lighting units,
An imaging step of imaging the workpiece illuminated by the lighting unit using the imaging unit, and
Based on the captured image, a specific step of illuminating the scattered matter generated by the processing of the workpiece and specifying the illuminating portion that forms a flare, and a specific step.
It is provided with an adjustment step of turning off or dimming the specified lighting unit .
The illumination unit illuminates the third spectral light including the reflected wavelength selectively reflected by the scattered object and the fourth spectral light including the non-reflective wavelength different from the reflected wavelength so as to be switchable.
In the lighting step, each of the plurality of lighting units is controlled to be sequentially illuminated by the third spectral light and the fourth spectral light.
In the specific step, the third spectral image captured when the third spectral light is irradiated is compared with the fourth spectral image captured when the fourth spectral light is irradiated. The third and fourth spectral images in which both positions match by comparing the position of the scattered object identified from the third spectral image with the position of the flare identified from the fourth spectral image. A method of imaging a machine tool , wherein the illumination unit corresponding to the above is specified as the illumination unit that illuminates the scattered object and forms the flare .

Images