JP2012091260A - Imaging type tool measurement device and measurement method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging type tool measurement device and an imaging type tool measurement method detecting a change in an imaging environment, automatically adjusting an imaging condition to measure dimensions of a tool with high accuracy and correcting images.SOLUTION: This imaging type tool measurement device includes: an imaging environment/condition detection part 25 for detecting an imaging environment/condition based on a signal of a tool image from an imaging part 12 or a processing signal from an image pre-processing part 20; an imaging condition determination/adjustment command part 27 for determining a proper condition for imaging based on the detection information in the imaging environment/condition detection part 25 to derive an adjustment command; and adjustment means for adjusting the imaging condition by an adjustment command signal from the imaging condition determination/adjustment command part 27.

Description

  The present invention relates to an imaging tool measurement apparatus and measurement method, and more particularly, to detect deterioration of an imaging environment and automatically adjust imaging conditions or correct an image so that tool dimensions can be measured with high accuracy. The present invention relates to an imaging tool measuring apparatus and a measuring method.

In the field of machine tools, the demand for machining accuracy is increasing year by year, and recently, it is not uncommon to require machining accuracy on the order of submicrons. In order to improve such processing accuracy, NC machine tools use an imaging device using an imaging device (for example, a CCD) in order to accurately measure the displacement of the cutting edge position of a tool during high-speed rotation.
Here, the tool mounted on the spindle is imaged, image processing is performed, the position of the cutting edge of the tool is measured, the shape and dimensions of the tool, such as the length and diameter, the measurement of the tool runout, the observation of the cutting edge, etc. Since the determination of the approach of the blade edge into the field of view is performed sequentially for each frame signal, the processing is slowed down, the blade edge entry cannot be detected and the SKIP signal cannot be output (SKIP is The tip of the tool T may collide with the workpiece. The SKIP signal is a signal that interrupts the blade tip entry operation command. When the SKIP signal is output, the movement of the feed shaft that causes the blade tip to enter is stopped.
In addition, since these measurements are based on image signals, they are easily affected by the imaging environment such as dirt on the visual field and illumination luminance. As a result, measurement is not possible and manual adjustment is often required.

  Conventionally, when shape recognition or dimension measurement is performed using image data of an imaging target by a CCD camera, an imaging target illumination device capable of obtaining edge-enhanced high-contrast imaging data in which the outer contour of the imaging target is clearly understood Is disclosed (for example, see Patent Document 1).

  In addition, as the machining progresses, even at the processing site, chips and cutting oil that adheres to the tool even if the imaging environment deteriorates, starting with tools and workpieces due to scattering of cutting chips and cutting oil, etc. An apparatus is disclosed in which the shape of a tool can be inspected with high accuracy by obtaining features of the outer shape of the tool itself that are not affected by foreign matters such as the above (see Patent Document 2).

Japanese Patent Laid-Open No. 9-83843 JP 2007-326196 A

However, in the former device disclosed in Patent Document 1, even if the arrangement of the light source is devised to obtain edge-enhanced high-contrast imaging data, the contrast and edge sharpness are detected, and based on these, the imaging environment is affected. It does not disclose that the element that gives the value is automatically adjusted.
On the other hand, even in the tool inspection apparatus of the latter patent document 2, even if the imaging environment deteriorates, by obtaining the characteristics of the outer shape of the tool itself, which is not affected by foreign matters such as chips and cutting oil attached to the tool, Even if the shape of the tool can be inspected with high accuracy, there is no suggestion that an element that affects the imaging environment is automatically adjusted so as to correct the influence of the deterioration of the imaging environment.

  The present invention has been proposed in order to improve the above-described problems. In the imaging tool measurement apparatus and measurement method, various imaging conditions at the time of machining are detected to obtain desired imaging conditions. Therefore, an object of the present invention is to provide an imaging type tool measuring apparatus and a measuring method which automatically adjust at least one of imaging condition elements and correct an image.

  In order to solve the above-described problem, the invention according to claim 1 includes an imaging unit that images a tool and a signal processing / control unit that performs image processing on an imaging signal from the imaging unit, and measures the dimensions of the tool. In the imaging type tool measuring apparatus, the signal processing / control unit includes an imaging environment / condition detection unit that detects an imaging environment / condition based on an imaging signal from the imaging unit or a signal obtained by performing image processing on the imaging signal, and an imaging environment Based on the information of the condition detection unit, the imaging condition determination / adjustment command unit for determining the imaging condition and deriving the adjustment command and the adjustment command signal from the imaging condition determination / adjustment command unit Adjusting means for adjusting the imaging condition.

Thereby, an imaging environment / condition can be grasped based on an imaging signal from the imaging unit or a signal obtained by performing image processing on the imaging signal.
Next, an imaging condition determination / adjustment command unit determines an appropriate imaging condition from a signal related to the imaging environment / conditions to derive an adjustment command signal, and the adjustment command signal determines the imaging condition (for example, illumination means, spindle control means) The adjustment signal for adjusting the shutter control means) is output, and the imaging environment / conditions can be suitably adjusted.

  According to the second aspect of the present invention, the imaging environment / condition detecting unit detects all or any plurality or one of image contrast, edge sharpness, exposure value, and spindle rotation speed.

  Thereby, the signal processing / control unit can grasp various imaging environments and conditions, and can contribute to the adjustment of the imaging environment of the measuring apparatus.

  According to a third aspect of the present invention, the imaging condition determination / adjustment command unit includes at least one of detection information of the imaging environment / condition detection unit and image contrast at the time of past imaging, edge sharpness, exposure value, and spindle rotation speed. From the two condition data, at least one of the illumination brightness, the shutter speed, the appropriate value of the sampling time, and the spindle speed as the imaging condition is determined.

  Thereby, it is possible to compare and judge the imaging environment, the time of cleaning (when serving as a reference), the timely time of measurement, or the imaging environment after measurement.

  In the invention according to claim 4, the adjusting means is adapted to an appropriate value based on the imaging condition determination / adjustment command unit, and at least of the illumination brightness, the shutter speed, the appropriate value of the sampling time, and the spindle rotation speed as the imaging condition. Adjust one.

  Thereby, it can contribute to the imaging environment adjustment of an imaging part. Here, an appropriate value is determined for the spindle rotational speed depending on the machining conditions, but when the image cannot be captured well at some timing, the spindle rotational speed is finely adjusted within a range that does not adversely affect the machining.

  According to a fifth aspect of the present invention, there is provided an imaging tool measuring method for measuring a tool size by performing image processing on a tool imaging signal, based on a tool imaging signal or a signal obtained by performing image processing on the imaging signal. It is characterized in that the conditions are detected, the imaging conditions are determined based on information relating to the imaging environment and conditions, an adjustment command is derived, and the imaging conditions are adjusted by the adjustment command signal.

Accordingly, it is possible to grasp the imaging environment / condition based on the imaging signal or a signal obtained by performing image processing on the imaging signal.
Next, it is possible to determine an appropriate imaging condition by deriving an adjustment command signal from a signal related to the imaging environment / condition, and to adjust the imaging condition based on the adjustment command signal.

  In the invention of claim 6, at least one of the contrast of the image when the imaging environment of the tool is clean, the sharpness of the edge, the exposure value, and the number of rotations of the spindle is acquired, and the illumination brightness as the imaging condition is determined. Predetermine at least one of shutter speed, appropriate value for sampling time, and spindle speed and store it as the imaging environment / condition when the imaging environment is clean. By comparing with the imaging environment / conditions at the time of cleaning, a change in the imaging environment is determined, and the imaging conditions are adjusted.

  As a result, the imaging environment / conditions are compared and determined and adjusted when the imaging environment is clean and at a later time, so the imaging tool measurement device is always adjusted to a good environment and condition. can do.

  According to the seventh aspect of the present invention, the captured image of only the imaging field of view at the time of cleaning the imaging environment is stored in advance, and the captured image of only the imaging field of view after the measurement is detected, and the imaging environment is cleaned. The difference image between the captured image with only the imaging field at the time and the captured image with only the imaging field after the measurement is determined as dirt adhesion on the imaging lens surface and the illumination unit, and the difference image is deleted from the field image at the subsequent imaging.

  As a result, the picked-up image of only the picked-up visual field stored at the time of cleaning the picking-up environment in the absence of the picked-up object, and the difference image with the picked-up image of the picked-up image pick-up only through the subsequent measurement are used for the imaging lens surface and illumination Since the difference image is deleted from the field image at the time of subsequent imaging, the imaging-type tool measuring device can always contribute to highly accurate measurement with no error.

  ADVANTAGE OF THE INVENTION According to this invention, the highly accurate and reliable imaging type tool measuring apparatus and method corresponding to automation can be provided.

It is a typical principal part side view which shows the place which incorporated the imaging type tool measuring apparatus concerning this invention in the corner of the process area of a machine tool. It is a block diagram which shows an example of the system configuration | structure of the imaging type tool measuring apparatus shown in FIG. In the imaging-type tool measuring apparatus according to the present invention, an example of a procedure for grasping an imaging environment / condition, determining an imaging condition, deriving an adjustment command, and adjusting an imaging condition of an imaging element of an imaging unit will be described. FIG.

Hereinafter, the imaging-type tool measuring apparatus according to the present invention will be described in detail with a specific example of the system configuration.
FIG. 1 shows a state in which an imaging tool measuring apparatus 10 according to the present invention is incorporated in an NC machine tool 1 such as an NC milling machine or a machining center.
The NC machine tool 1 has a table 3 on a base 2 that can be moved vertically and horizontally in the XY-axis direction, and a spindle 5 that is movable up and down on a column 4 in the Z-axis direction orthogonal to the table 3. A tool T is mounted on the main shaft 5. And the imaging type tool measuring apparatus 10 which mounts an image with the tool T as an imaging target and performs tool dimension measurement or the like with the tool T interposed therebetween is mounted.

  In FIG. 2, the system block diagram of the imaging type tool measuring apparatus 10 is shown. The NC machine tool 1 processes a workpiece by causing relative movement between a spindle 5 on which a tool T is mounted by numerical control and a table 3 on which a workpiece (not shown) is fixed.

This imaging type tool measuring apparatus 10 includes an imaging unit 12 incorporated in a housing 11 mounted on the table 3 of the NC machine tool 1, performs predetermined signal processing on an image signal from the imaging unit 12, and will be described later. The configuration is such that image data is sent to a signal processing / control unit 13 that performs calculations and generates various processing signals and command signals.
The imaging-type tool measuring apparatus 10 acquires an image signal from the imaging unit 12 for the tool T mounted on the spindle 5 and performs predetermined signal processing on the image signal in the signal processing / control unit 13. Then, judgments and calculations described later are performed, various processing signals and command signals are issued, adjustment command signals corresponding to various constituent means for determining the imaging environment are sent, and the imaging environment is adjusted.

The imaging unit 12 causes the light source L that illuminates the tool T to be imaged and the light beam that has passed through the tool T as a parallel beam via the condenser lens 14 to pass through the imaging lens group 15 and form an image on the light receiving surface. An image sensor 16 that converts an image into an electrical signal, and an A / D converter 17 that converts an electrical signal acquired by the image sensor 16 into digital data and sends the digital data to a signal processing / control unit 13 described later. Yes.
The tool T assumes various shapes such as a drill, a ball end mill, and a flat end mill.
The imaging lens group 15 is for adjusting the luminous flux so that the light beam that has passed through the tool T passes through the imaging lens group 15 so that the entire image is formed on the imaging element 16 to be described later. Each is configured by a combination of a convex lens, a concave lens, and the like with a predetermined magnification, which are arranged so as to match.
The imaging device 16 is a two-dimensional CCD image sensor, which generates an electrical signal from an optical signal related to an incident image, and is taken out as an analog signal.

In the imaging unit 12 as described above, in the optical path from the imaging lens group 15 to the imaging device 16, ½ of the imaging light beam is transmitted along the optical path and is incident on the imaging device 16, while the remaining result. A beam splitter 18 (hereinafter referred to as a half mirror 18) for detecting the approach of the cutting edge of the tool T by polarizing the image light beam in a direction orthogonal to the optical path is interposed.
That is, although not shown in the drawing as the blade edge detection unit, for example, in the imaging unit 12, the half mirror 18 interposed in the optical path from the imaging lens group 15 to the imaging element 16 is 1 / of the imaging light beam. A cylinder lens that linearly converts image light polarized in a direction orthogonal to the optical path 2 and a line sensor that converts the linearly converted image signal from the cylinder lens into a linear electrical signal It comprises. When the tool T enters the image acquisition range, the line sensor detects the image as a shaded image signal and outputs a SKIP signal to the CNC machine tool operation control unit to stop the machine tool.

  Moreover, the following configuration is also possible for a blade edge | tip approach detection part. In other words, the blade edge entry detection unit narrows the image separated by the half mirror 18 from the optical path before the imaged image is formed into a spot shape through the diaphragm member, and further collects the image in a dot shape through the condenser lens. The light is made incident on the phototransistor. The phototransistor is turned on / off by detecting whether or not the point-like incident light has reached a certain level of intensity, and is sent to the tool presence / absence detecting means. The presence / absence of the entry can be grasped, and the SKIP signal can be generated by the SKIP signal generating means, and the SKIP signal can be output to the CNC machine tool operation control unit to stop the tool entry operation of the machine tool.

  Further, the blade edge detection unit is not contacted with the half mirror 18, and a laser detection unit or a proximity sensor, which is a non-contact type detection unit, is disposed in the field of view of the processing unit 2 so that the tool enters. Can also be detected.

The overall configuration of the signal processing / control unit 13 will be described schematically.
The signal processing / control unit 13 includes an image preprocessing unit 20 that takes in digital data obtained by converting the electrical signal acquired by the image sensor 16 by the A / D converter 17 and performs known preprocessing. That is, the image preprocessing unit 20 performs shading correction, noise reduction, white balance, contour correction, and contrast adjustment, and sequentially outputs them to the image display means 21 to display an image in real time or to detect an imaging environment / conditions described later. The image is sequentially sent to the frame memory 22 by image storage control.
The data written in the frame memory 22 is sequentially sent to the visual field contamination detection unit 23 and the tool measurement / calculation unit 24 to detect visual field contamination due to various factors, or to rotate the tool T that rotates at high speed. The measurement results are measured and the measurement results are output.

  The atmosphere around the workpiece that is machined by rotating the spindle and moving in the direction of each axis is filled with cutting oil mist and chips scattered during machining, and adheres to the peripheral wall or on the surface of the optical system. The contamination is generated and hinders measurement with high accuracy and high reliability. Therefore, the visual field contamination detection unit 23 grasps the degree of contamination and derives a correction value to the tool measurement / calculation unit 24. Send it out. That is, the visual field contamination detection unit 23 uses the data from the frame memory 22 to obtain visual field image acquisition means for acquiring a visual field image, visual field image storage means for storing the acquired image, and visual field contamination image from the visual field image storage means. A visual field dirt image extracting means for extracting and a visual field dirt image storing means for storing the visual field dirt image are provided. The visual field image acquisition unit and the visual field contamination image extraction unit execute an acquisition operation and an image extraction operation, respectively, according to a control command from the visual field contamination detection control unit.

  The tool measurement / calculation unit 24 includes a field-dirt image removing unit that reads data from the frame memory 22 and data in the field-dirt image storage unit of the field-dirt detection unit 23 and removes the field-stained image. From the data obtained through the removing means, the step of extracting the contour of the tool T and the step of recognizing the shape are sequentially executed, and the blade position calculation, the tool diameter calculation, and the deflection calculation for deriving high-speed tool deflection Is executed and output as a measurement result.

The signal processing / control unit 13 includes an imaging environment / condition detection unit 25.
The imaging environment / condition detection unit 25 detects an imaging environment / condition based on an imaging signal from the imaging unit 12 or a signal obtained by subjecting the imaging signal to image processing. Details of the imaging environment / condition detection unit 25 will be described later. All or any plural number or one of the sharpness, the degree of exposure, and the rotational speed of the spindle are set as detection targets.
The imaging environment / condition detection unit 25 performs contrast determination (shading degree) by comparing the voltage value of the image signal after contrast adjustment in the image preprocessing unit 20 and the appropriate contrast value storage unit 26 (reference voltage value). As will be described later, the signal is sent to the imaging condition determination / adjustment command unit 27 as a detection signal of the imaging environment / condition.

The imaging environment / condition detection unit 25 detects the number of rotations of the spindle 5 on which a tool is mounted as a detection target. The rotational speed of the main shaft 5 is one of the elements that determine the imaging environment of the imaging unit 12. That is, the image signal of the tool T that is imaged varies depending on the number of rotations of the tool T, and accordingly, the degree of illumination brightness as an imaging environment is affected.
The spindle 5 is controlled to rotate by the spindle control means 28, but the imaging environment / condition detection unit 25 detects the rotation speed of the spindle from the spindle control means 28 using the spindle rotation speed detection means 29, and performs imaging. The detection signal is sent to the imaging condition determination / adjustment command unit 27 as an environment / condition detection signal.

  The imaging environment / condition detection unit 25 is one of the elements that determine the imaging environment of the imaging unit 12, and uses edge sharpness as a detection target. The imaging environment / condition detection unit 25 determines the sharpness of the edge (for example, the image data gradation degree of the contour of the tool T) from the data from the frame memory 22, that is, the image signal of the tool T, and detects the imaging environment / condition. A signal is sent to the imaging condition determination / adjustment command unit 27 as a signal.

  Furthermore, the imaging environment / condition detection unit 25 is one of the elements that determine the imaging environment of the imaging unit 12 and uses the exposure level as a detection target. The imaging environment / condition detection unit 25 performs exposure detection from digital data obtained by converting the electrical signal acquired by the imaging device 16 by the A / D converter 17 and determines exposure based on the appropriate exposure value storage unit 30. And is sent to the imaging condition determination / adjustment command unit 27 as a signal of the imaging environment / condition.

  In the imaging condition determination / adjustment command unit 27, the imaging unit 12 is appropriately in a desired imaging environment in which highly accurate image data of the tool T can be obtained based on the signals relating to the imaging environment / conditions as described above. If it is not in such an imaging environment, an adjustment command is issued to an element that determines the imaging environment of the imaging unit 12 so as to correct the imaging environment so that the imaging condition is adjusted. -ing

  For example, for the light source L as an element that determines the imaging environment of the imaging unit 12, the imaging condition determination / adjustment command unit 27 controls the predetermined illumination adjustment unit 31 (dimming circuit) to adjust the luminance. .

  For the spindle 5 on which the tool T is mounted, the imaging condition determination / adjustment command unit 27 gives an adjustment command signal for changing the rotation speed to the spindle control means 28 to increase or decrease the rotation speed of the spindle 5.

  For the A / D converter 17 that converts the electrical signal acquired by the image sensor 16 into digital data, the imaging condition determination / adjustment command unit 27 sends an adjustment command to the shutter control unit 32. Adjust the sampling time to change the frame rate.

  Further, the imaging condition determination / adjustment command unit 27 changes the digital data conversion range by giving an adjustment command signal to the aperture control means 33.

  In addition, when the position of the tool T as the measurement target on the table is deviated from the imaging range, the imaging condition determination / adjustment command unit 27 places the measurement apparatus 10 on the measurement target position changing unit 34. An adjustment command signal is sent to adjust the movement of the table 3 in the XY directions.

  In addition, when the table 3 for fixing the workpiece, the workpiece or the like is attached with chips or cutting oil generated by machining, or the atmosphere around the machining is where the mist of cutting oil is floating, the imaging conditions The judgment / adjustment command unit 27 sends a control command signal to the air blow control means 35 so as to inject high-pressure air around the workpiece.

The imaging condition determination / adjustment command unit 27 includes information of the imaging environment / condition detection unit 25 and condition data of image contrast at the time of past imaging, edge sharpness, exposure value, and spindle rotation speed (imaging environment storage unit 36), the illumination brightness, the shutter speed, the appropriate value of the sampling time, and the spindle speed as the imaging conditions are determined.
That is, prior to the start of the measurement operation, the imaging condition determination / adjustment command unit 27 causes the imaging environment / condition detection unit 25 to perform illumination brightness, shutter speed, appropriate sampling time, and spindle rotation as imaging conditions when the imaging environment is clean. The number detected in advance is stored in the imaging environment storage means 36 as the imaging environment / condition when the imaging environment is clean, and the imaging environment / condition detection unit 25 detects the imaging environment / condition at a later time in a timely manner, The imaging condition determination / adjustment command unit 27 determines a change in the imaging environment by comparing with the imaging environment / condition when the imaging environment is clean, and adjusts the imaging condition.

  Furthermore, the imaging environment storage means 36 stores in advance a captured image of only the imaging field of view when the imaging environment is clean, such as the tool T, and after the measurement is used, the captured image without the imaging target is stored. Is detected by the imaging environment / condition detection unit 25, and the imaging condition determination / adjustment command unit 27 captures a difference image between the captured image of the imaging field only when the imaging environment is clean and the captured image of only the imaging field after measurement. It is determined that the lens 15 surface and the light source L are contaminated, and the difference image is deleted from the visual field image at the time of subsequent imaging.

  Prior to the start of the measurement operation, the measurement apparatus 10 performs the above-described imaging environment determination and adjustment at a later timely timing, and further through subsequent measurement use. It can always contribute to highly accurate measurement without error.

  Next, a procedure for specifically adjusting the imaging environment of the imaging tool measuring apparatus 10 will be described based on an example of a flowchart shown in FIG.

  In response to the measurement operation start command, the NC machine tool 1 rotates and drives the tool T mounted on the spindle 5, issues a lowering command along the Z-axis direction, and moves it downward toward the workpiece fixed to the table 3. Thereby, the tool T which is the measurement object in the rotating state can be caused to enter from the light source L into the visual field incident as a parallel light beam through the condenser lens 14 (STEP 1).

  Light rays that have passed through the tool T as parallel rays from the light source L via the condenser lens 14 pass through the imaging lens group 15, pass through the half mirror 18, and are received by the two-dimensional CCD image sensor that is the imaging element 16. The image is formed on the surface. The formed image is converted into an electric signal by the image pickup device 16, and this electric signal is converted into digital data at a predetermined frame rate by the A / D converter 17, and the image preprocessing unit 20 of the signal processing / control unit 13. Is sent out.

The signal processing / control unit 13 acquires an exposure value from the A / D converter 17 (STEP 2), extracts an exposure detection signal, and sends the exposure detection signal to the imaging environment / condition detection unit 25. The imaging environment / condition detection unit 25 It is determined whether or not the exposure value is an appropriate exposure value (STEP 3). In STEP 3, the imaging environment / condition detection unit 25 performs exposure determination based on the appropriate exposure value storage unit 30, and the imaging condition determination / adjustment command unit 27 determines that the exposure value is within the appropriate exposure value. Assuming that there is a preferable imaging environment, the procedure for adjusting the exposure value, which is one of the imaging conditions, is terminated.
On the other hand, when the imaging environment / condition detection unit 25 determines that the exposure value is not the appropriate exposure value, the imaging condition determination / adjustment instruction unit 27 detects the imaging environment / condition as a signal indicating another imaging environment / condition. In addition to acquiring the spindle rotation speed from the unit 25 (STEP 4), the contrast value is acquired (STEP 5), and the sharpness of the contour of the tool T determined by the imaging environment / condition detection unit 25 is acquired as the edge degree ( (STEP6).

  In STEP 4, the imaging condition determination / adjustment command unit 27 acquires the spindle rotation speed based on the detection signal from the spindle rotation speed detection unit 29 in the imaging environment / condition detection unit 25, and then performs A / D conversion from the spindle rotation speed. The shutter speed for acquiring digital data is determined in the device 17 (STEP 7). Next, the imaging condition determination / adjustment command unit 27 determines whether or not the rotation speed of the spindle 5 needs to be adjusted (STEP 8). If the rotation speed needs to be adjusted, an adjustment command is issued to the spindle control means 28 (STEP 9), the rotation speed of the spindle 5 is adjusted, and the process returns to STEP2. On the other hand, if it is not necessary to adjust the rotational speed, the imaging condition determination / adjustment command unit 27 calculates an appropriate shutter speed suitable for the rotational speed (STEP 10), and issues an adjustment command to the shutter control means 32 (STEP 11). The A / D converter 17 changes the shutter speed for acquiring digital data, and the process returns to STEP2.

When acquiring the contrast value in STEP 5 described above, the imaging environment / condition detection unit 25 compares the processed signal from the appropriate contrast value storage unit 26 and the processing signal from the image preprocessing unit 20 as a contrast value. Then, the signal is sent to the imaging condition determination / adjustment command unit 27 as a signal indicating the imaging environment / condition, and the imaging condition determination / adjustment command unit 27 determines whether or not the contrast value is an appropriate value (STEP 12). If the contrast value is an appropriate value, it is determined that the imaging environment is preferable, and the procedure for adjusting the imaging environment is terminated. On the other hand, if the contrast value is not an appropriate value, the imaging condition determination / adjustment command unit 27 determines whether or not the illumination needs to be adjusted (STEP 13).
When it is determined in STEP 13 that the illumination needs to be adjusted, the imaging condition determination / adjustment command unit 27 calculates an appropriate illumination intensity (STEP 14), and issues an adjustment command to the illumination adjustment means 31 ( (STEP 15) The light source L is adjusted and the process returns to STEP 2. On the other hand, when it is determined that the illumination adjustment is not necessary, the imaging condition determination / adjustment command unit 27 calculates an appropriate aperture value (STEP 16), and the aperture control unit 33 By giving the adjustment command signal (STEP 17), the conversion range of the digital data is changed, and the process returns to STEP 2.

  In STEP 6 described above, when acquiring the edge degree, the imaging condition determination / adjustment instruction unit 27 takes in a signal related to the edge degree from the imaging environment / condition detection unit 25 as a signal indicating the imaging environment / condition, and the edge The determination is made based on the degree, that is, whether or not the contour of the tool T image is clear in order to determine whether it is an appropriate value (STEP 18). If the edge degree is an appropriate value, the imaging condition determination / adjustment instruction unit 27 ends the procedure for adjusting the edge degree as the imaging condition, assuming that the imaging environment is preferable. On the other hand, if the edge degree is not an appropriate value, the process returns to STEP 13 and the imaging condition determination / adjustment command unit 27 determines whether or not the illumination needs to be adjusted.

As described above, the procedure for adjusting the imaging environment described above is captured as a signal indicating the imaging environment / condition one by one, and the imaging condition determination / adjustment command is repeatedly executed in parallel with the measurement operation. The measurement apparatus 10 can always contribute to high-precision and high-reliability measurement, and a high-accuracy and high-reliability imaging-type tool measurement apparatus and method corresponding to automation can be provided.
Note that the above-described procedure for adjusting the imaging environment is an example, and it is a matter of course that the procedure for adjusting the imaging environment can be set as appropriate according to the function and specification of the machine tool. In the present embodiment, the SKIP signal is generated using the image separated by the half mirror 18, but the SKIP signal is generated using the image acquired by the image sensor 16 without using the half mirror 18. Also good.

DESCRIPTION OF SYMBOLS 1 NC machine tool 2 Base 3 Table 4 Column 5 Spindle 10 Imaging type tool measuring apparatus 11 Housing 12 Imaging part 13 Signal processing / control part 14 Condenser lens 15 Imaging lens group 16 Imaging element 17 A / D converter 18 Half mirror 20 Image Preprocessing section 21 Image display means 22 Frame memory 23 Field dirt detection section 24 Tool measurement / calculation section 25 Imaging environment / condition detection section 26 Appropriate contrast value storage section 27 Imaging condition judgment / adjustment instruction section 28 Spindle control section 29 Spindle speed Detection means 30 Appropriate exposure value storage means 31 Illumination adjustment means 32 Shutter control means 33 Aperture control means 34 Position change means for measurement object 35 Air blow control means 36 Imaging environment storage means T tool

Claims (7)

In an imaging-type tool measuring device that has an imaging unit that images a tool, and a signal processing / control unit that performs image processing on an imaging signal from the imaging unit, and measures the dimensions of the tool,
The signal processing / control unit includes an imaging environment / condition detection unit that detects an imaging environment / condition based on an imaging signal from the imaging unit or a signal obtained by performing image processing on the imaging signal;
Based on information of the imaging environment / condition detection unit, an imaging condition determination / adjustment command unit that determines an imaging condition and derives an adjustment command;
An adjustment unit that adjusts an imaging condition of an imaging element of the imaging unit according to an adjustment command signal from the imaging condition determination / adjustment command unit;
An imaging-type tool measuring device comprising:   2. The imaging tool measurement apparatus according to claim 1, wherein the imaging environment / condition detection unit detects all or any plurality or one of image contrast, edge sharpness, exposure value, and spindle rotation speed. .   The imaging condition determination / adjustment command unit captures an image from at least one condition data of detection information of the imaging environment / condition detection unit and past image contrast, edge sharpness, exposure value, and spindle rotation speed. The imaging tool measuring apparatus according to claim 1, wherein at least one of illumination brightness, shutter speed, sampling time appropriate value, and spindle speed as conditions is determined.   The adjustment means adjusts at least one of illumination brightness, shutter speed, appropriate value of sampling time, and spindle rotation speed as imaging conditions so as to conform to an appropriate value based on the imaging condition determination / adjustment command unit. Item 1. The imaging tool measuring device according to Item 1. In an imaging tool measuring method for measuring the dimensions of a tool by performing image processing on the imaging signal of the tool,
An imaging environment / condition is detected based on an imaging signal of the tool or a signal obtained by performing image processing on the imaging signal,
Based on the information related to the imaging environment and conditions, determine the imaging conditions, derive an adjustment command,
An imaging type tool measuring method, wherein the imaging condition is adjusted by the adjustment command signal.   Obtain at least one of image contrast, edge sharpness, exposure value, and spindle rotation speed when the imaging environment of the tool is clean, and determine the appropriate illumination brightness, shutter speed, and sampling time as imaging conditions At least one of a value and a spindle rotational speed is preliminarily stored and stored as an imaging environment / condition when the imaging environment is cleaned, and an imaging environment / condition is detected at a later time and the imaging environment is cleaned when the imaging environment is cleaned 6. The imaging tool measurement method according to claim 5, wherein a change in imaging environment is determined by comparing with a condition, and the imaging condition is adjusted.   The captured image of only the imaging field of view when the imaging environment is cleaned is stored in advance, the captured image of only the imaging field of view after the measurement is detected through the subsequent measurement, and the imaging field only when the imaging environment is cleaned is captured. The imaging according to claim 5, wherein a difference image between the image and the captured image of only the imaging field after the measurement is determined as dirt adhesion on the imaging lens surface and the illumination unit, and the difference image is deleted from the field image during subsequent imaging. Type tool measurement method.

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