JP2015182159A - Measuring apparatus for tool displacement of machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring apparatus for a tool displacement of a machine tool that can exactly measure a displacement of a tool tip position with a simple constitution.SOLUTION: The measuring apparatus comprises a camera 14, first and second luminaires 15 and 16, a movable reflector 17, and image processing means that analyzes a tool tip position from an image of a tool T photographed by the camera. The first luminaire is disposed opposite the camera, and the second luminaire is disposed in a direction orthogonal to a photographing direction of the camera via the reflector on the same level with the camera and the first luminaire. While the first luminaire illuminates the tool positioned at a first photographing region, the camera photographs the tool to move the reflector to a photoreflection position. While the second luminaire illuminates the tool positioned at a second photographing region, the camera photographs an image of the tool reflected by the reflector. The image processing means arithmetically operates the tool tip position from tool images in the first and second photographing regions.

Description

  The present invention relates to a tool displacement measuring device for a machine tool that measures a displacement of a tip position of a tool of a machine tool.

  When machining with a tool rotated by a machine tool, the tip position of the tool is displaced due to heat generated by the rotation or temperature change around the machine. For this reason, a tool displacement measuring device for a machine tool is mounted on the machine, the displacement of the tool tip position is measured in a non-contact manner, and the tool tip position is corrected based on the measurement result. I try to suppress it.

  As the tool displacement measuring device of the machine tool, there are a laser type device and an imaging type device using a camera. For example, Patent Document 1 below includes a camera unit, an illumination unit, a contact displacement meter, a laser displacement meter, and the like, and performs horizontal calibration based on images obtained by the camera unit and the illumination unit. An apparatus for vertical calibration based on data obtained by a meter is disclosed.

JP 2010-64203 A

  However, although the apparatus described in Patent Document 1 can horizontally calibrate the tool tip position, it combines a plurality of mirrors, half mirrors, and cameras so that two images of the tool and the target mark can be captured. The apparatus itself was complicated. Although the tip position of the tool can be calibrated vertically, the contact displacement meter measures the amount of physical movement of the tool by contact with the tip of the tool, making measurement impossible while rotating the tool. Therefore, the displacement due to the heat generated by the rotation could not be measured.

  In view of the above, the present invention has been made to solve the above-described problems, and provides a tool displacement measuring device for a machine tool that can accurately measure the displacement of the tip position of a tool with a simple configuration. It is intended to provide.

A tool displacement measuring device for a machine tool according to the present invention that solves the above-mentioned problems is as follows.
A tool displacement measuring device for a machine tool for measuring a displacement of a tip position of a tool of a machine tool,
Photographing means for photographing the tool;
First and second illumination means for irradiating the tool with light;
Reflecting means for reflecting the light;
Moving means for moving the reflecting means;
Image processing means for analyzing the tip position of the tool from the image of the tool photographed by the photographing means,
The first illuminating means is disposed opposite to the photographing means, while the second illuminating means is in the same plane as the first illuminating means and the photographing means and the photographing direction of the photographing means via the reflecting means. Arranged perpendicular to the
When the tool is arranged in a first imaging region between the imaging unit and the first illumination unit, the moving unit moves the reflecting unit to a position away from the imaging field of view of the imaging unit, and One illuminating means illuminates the tool, while the imaging means images the tool;
When the tool is arranged in a second imaging region facing the second illumination means, the moving means moves the reflection means to a position where the light from the second illumination means is reflected to the imaging means side, and While the second illumination means illuminates the tool, the imaging means captures an image of the tool reflected by the reflecting means,
The image processing means measures the tip position of the tool based on the image of the tool in the first imaging region and the image of the tool in the second imaging region.

Also,
The first illumination unit, the second illumination unit, and the photographing unit are arranged on the same horizontal plane.

Also,
The photographing means, the first illumination means, the second illumination means, the reflection means are covered, the photographing direction by the photographing means, the light irradiation direction by the first and second illumination means, the reflection of light by the reflection means A cover with a window formed in the direction;
And a shutter capable of shielding the window.

Also,
The reflecting means is provided on the shutter;
The moving means is the shutter.

  According to the tool displacement measuring apparatus for a machine tool according to the present invention, the photographing means, the first and second illuminating means, the reflecting means, the moving means, and the image processing means are provided, and the photographing means and the first and second illuminating means. And the four reflecting means are arranged so as to have a predetermined relationship, the positions in three orthogonal directions at the tip of the tool of the machine tool can be measured. Therefore, the displacement of the tip position of the tool can be accurately measured with a simple configuration.

FIG. 1 is a schematic diagram for explaining an embodiment of a tool displacement measuring device for a machine tool according to the present invention, and FIG. 1 (a) shows a state in which a reflecting mirror is arranged outside the field of view of a camera; (B) shows a state in which the reflecting mirror is arranged at the light reflection position (photographing field of view of the camera) by the second illumination device. It is the schematic of one Embodiment of the tool displacement measuring apparatus of the machine tool which concerns on this invention. It is a block diagram of one embodiment of a tool displacement measuring device of a machine tool concerning the present invention. It is the schematic of one Embodiment of the tool displacement measuring apparatus of the machine tool which concerns on this invention, Comprising: The case where a window part is shielded with the 2nd shutter is shown to Fig.4 (a), and the 1st shutter is shown in FIG.4 (b). The case where a window part is shielded by is shown.

  An embodiment of a tool displacement measuring device for a machine tool according to the present invention will be described with reference to FIGS.

  The tool displacement measuring device for a machine tool according to the present embodiment is a device for measuring the displacement of the tool T included in the machine tool. The tool T includes, for example, a column placed on a bed constituting a base, a spindle head that is slidably supported on one side of the column, and a spindle that is rotatably supported by the spindle head. In a machine tool provided, the machine tool is detachably supported by the spindle. That is, the tool T can be placed at a predetermined location by the machine tool, and the machine tool serves as a tool moving means.

  As shown in FIG. 1, a tool displacement measuring device 10 for a machine tool according to this embodiment includes a base 11, a camera (photographing means) 14, a first illumination device (first illumination device) 15, and a second illumination device ( A second illuminating means) 16 and a reflecting mirror (reflecting means) 17.

  The base 11 is disposed, for example, at a location adjacent to a location where the machine tool processes a workpiece on a table disposed in front of the column of the machine tool. The base 11 has a first base portion 11a and a second base portion 11b that have a rectangular parallelepiped shape. The second base portion 11b is connected to the substantially central portion of the first base portion 11a so as to be orthogonal to the extending direction of the first base portion 11a on the same plane as the first base portion 11a. That is, the base 11 is substantially T-shaped in plan view. The first base portion 11a is formed in a size that allows the camera T and the first illumination device 15 to photograph the tool T when the tool T is disposed in a first imaging region 41 described later. The second base portion 11b arranges the tool T in a second imaging region 42, which will be described later in detail, and the camera 14, the second illumination device 16, and the reflection when the reflecting mirror 17 is disposed in a light reflection position, which will be described later in detail. The mirror 17 is formed in a size capable of photographing the tool T.

  The camera 14 is fixed to one end of the first base 11 a of the base 11. The camera 14 is a CCD camera, for example, and images the tip of the tool T arranged in the first imaging region 41 by a machine tool, and is arranged in the second imaging region 42 by the machine tool and reflected by the reflecting mirror 17. An image of the tip of the tool T is taken.

  The first lighting device 15 is fixed to the other end of the first base 11 a of the base 11. The 1st illumination device 15 illuminates the front-end | tip of the tool T arrange | positioned in the 1st imaging | photography area | region 41 with the machine tool, and its vicinity.

  The camera 14 and the first illumination device 15 are disposed to face each other, and the camera axis A2 that is the shooting direction of the camera 14 and the optical axis A1 that is the light irradiation direction by the first illumination device 15 coincide with each other. Are arranged as follows. Here, a direction parallel to the camera axis A2 of the camera 14 and the optical axis A1 of the first illumination device 15 is defined as a Y-axis direction, and a vertical direction is defined as a Z-axis direction.

  The second lighting device 16 is fixed to the end of the second base portion 11 b of the base 11. The second illumination device 16 illuminates the tip of the tool T disposed in the second imaging region 42 and the vicinity thereof by the machine tool. The second illuminating device 16 is arranged between the camera 14 and the first illuminating device 15 while the optical axis A3 that is the light irradiation direction by the second illuminating device 16 is arranged on the same horizontal plane as the Y axis. The camera 14 is arranged so as to be orthogonal to the camera axis A2. The optical axis A3 of the second illumination device 16 is a direction orthogonal to the Y-axis direction and is set to the X-axis direction.

  The reflecting mirror 17 is supported by the support 18 and is held at a predetermined angle on the XY plane. The reflecting mirror 17 is provided so as to be movable between a light reflecting position for reflecting the light from the second illumination device 16 toward the camera 14 and a position outside the photographing field that is separated from the light reflecting position and deviates from the photographing field of the camera 14. It is done.

  The above-described tool displacement measuring apparatus 10 for a machine tool further includes a cover 20 and first and second shutters 31 and 32 as shown in FIG. Thereby, the whole apparatus can be covered so that the displacement of the tool T can be measured, such as processing waste (for example, chips) and processing oil (for example, cutting oil) generated when a workpiece is processed by the tool T. The camera 14 and the first and second lighting devices 15 and 16 and the reflecting mirror 17 can be protected from foreign matters.

  The cover 20 is formed so as to constitute a photographing room 21, a first lighting room 22, a second lighting room 23, a first communication room 24, and a second communication room 25.

  The photographing room 21 is configured to cover the camera 14. A first photographing window portion 21 a is formed in the cover 20 covering the photographing room 21 in the extending direction of the camera axis A <b> 2 of the camera 14. Further, the cover 20 covering the photographing room 21 is formed with a second photographing window portion 21b in the direction of reflection of the camera axis A2 by the reflecting mirror 17 (the extending direction of the optical axis A3 of the second illumination device 16).

  The first lighting chamber 22 is configured to cover the first lighting device 15. A first illumination window 22 a is formed in the cover 20 that covers the first illumination chamber 22 in the extending direction of the optical axis A <b> 1 of the first illumination device 15.

  The second lighting chamber 23 is configured to cover the second lighting device 16. A second illumination window 23 a is formed in the cover 20 covering the second illumination chamber 23 in the extending direction of the optical axis A <b> 3 of the second illumination device 16.

  The photographing room 21 and the first lighting room 22 communicate with each other through the first communication room 24.

  The imaging room 21 and the second illumination room 23 communicate with each other through the second communication room 25.

  The first and second shutters 31 and 32 are substantially U-shaped in plan view. The first shutter 31 is provided so as to be movable up and down, and opens and closes the first photographing window 21a and the first illumination window 22a by moving up and down. The second shutter 32 is provided so as to freely move up and down, and opens and closes the second photographing window 21b and the second illumination window 23a by moving up and down.

  A reflecting mirror 17 is attached to the first shutter 31 on the side facing the camera 14 via a support 18. The reflecting mirror 17 arranges the first shutter 31 at a position where the first photographing window 21a and the first lighting window 22a are shielded, while the second photographing window 21b and the second lighting window 23a are arranged. When the second shutter 32 is arranged at the opening position, the optical axis A3 of the second illumination device 16 and the camera axis A2 of the camera 14 are arranged so as to coincide with each other. Therefore, when the first shutter 31 is opened and closed, the reflecting mirror 17 is moved to a position away from the shooting field of view of the camera 14, and the reflecting mirror 17 is moved to a position where the light from the second illumination device 16 is reflected to the camera 14 side. be able to.

  The above-described tool displacement measuring device 10 for a machine tool further includes air injection nozzles 33a, 33b, 33c, and 33d that inject air toward the window portions 21a, 21b, 22a, and 23a. By injecting air from these air injection nozzles 33a, 33b, 33c, and 33d, it is possible to prevent the foreign matter from entering the cover 20 described above.

  Further, as shown in FIG. 3, the above-described tool displacement measuring device 10 for a machine tool is provided in connection with a camera 14, a first illumination device 15, a second illumination device 16, a first shutter 31, and a second shutter 32. And the image processing device 51 provided in connection with the camera 14 and the control device 50. The control device 50 controls the camera 14, the first and second illumination devices 15 and 16, the first and second shutters 31 and 32, and the image processing device 51. The control device 50 is also connected to the above-described machine tool that forms the tool moving means, and the control device 50 also controls the machine tool.

  The image processing device 51 analyzes the tip position of the tool T from the image of the tool T taken by the camera 14. Specifically, the image processing device 51 is obtained by photographing the tool T while the first illumination device 15 illuminates the tool T when the tool T is arranged in the first photographing region 41. When the image of the tool T and the tool T are arranged in the second imaging region 42, the reflecting mirror 17 is arranged at the light reflecting position, and the second illumination device 16 illuminates the tool T, while the camera 14 is the tool. The coordinate position is obtained by measuring (calculating) the tip position of the tool T based on the image of the tool T obtained by photographing T.

  Here, the procedure for measuring the displacement of the tool T by the control device 50 included in the tool displacement measuring device 10 of the above-described machine tool will be described below with reference to FIGS. Before measuring the displacement of the tool T, as shown in FIG. 2, the first shutter 31 is disposed so as to shield the first photographing window 21a and the first illumination window 22a, and the second shutter. 32 is arranged so as to shield the second imaging window 21b and the second illumination window 23a. The air injection nozzles 33a to 33d are controlled so as to always inject air toward the window portions 21a, 21b, 22a, and 23a.

  First, as shown in FIG. 4A, the machine tool places the tool T in the first imaging region 41.

  Subsequently, the first shutter 31 is moved to a position where the first photographing window 21a and the first illumination window 22a are opened, and the first illumination device 15 emits light toward the tool T, while the camera 14 Shoots the tool T. The image processing device 51 measures the displacement (X coordinate and Z coordinate) of the tip position of the tool T in the X axis direction and the Z axis direction by processing the obtained image of the tool T by a conventional image processing technique. (Calculate). The second shutter 32 is arranged at a position that shields the second photographing window 21b and the second illumination window 23a.

  Subsequently, in the first imaging region 41, when the measurement of the tip position of the tool T is completed, the first illumination device 15 is turned off while the first imaging window portion 21a and the first illumination window portion 22a are shielded. The first shutter 31 is moved. Thereby, the reflecting mirror 17 is arrange | positioned in the position which reflects the light which the 2nd illuminating device 16 irradiates to the camera 14 side.

  Subsequently, as shown in FIG. 4B, the machine tool places the tool T in the second imaging region 42.

  Subsequently, the second shutter 32 is moved to a position where the second photographing window 21b and the second illumination window 23a are opened, and the second illumination device 16 emits light toward the tool T, while the camera 14 An image of the tool T reflected by the reflecting mirror 17 is taken. The image processing device 51 measures (calculates) the displacement (Y coordinate) of the tool T in the Y-axis direction by processing the obtained image of the tool T by a conventional image processing technique. The first shutter 31 is disposed at a position that shields the first photographing window 21a and the first illumination window 22a.

  Subsequently, in the second measurement region 42, when the measurement of the tip position of the tool T is completed, the second illumination device 16 is turned off, while the second imaging window 21b and the second illumination window 23a are shielded. The second shutter 32 is moved.

  Therefore, according to the tool displacement measuring device 10 of the machine tool according to the present embodiment, the camera 14, the first illumination device 15, the second illumination device 16, and the reflecting mirror 17 disposed at predetermined positions are provided. It is possible to measure the displacement of the tip position (X coordinate, Y coordinate, Z coordinate) of the tool T only by operating in this order. In other words, the displacement of the tip position of the tool T can be accurately measured with a simple configuration.

  The X axis and Y axis at the tip of the tool T can be obtained simply by arranging the camera 14, the first illumination device 15 and the second illumination device 16 at a substantially T-shaped apex, and disposing the reflecting mirror 17 at the intersection of the approximately T-shape. Since the displacement in the three directions of the Z axis can be measured, three sets of the X axis, the Y axis, and the Z axis at the tip of the tool T using two sets of tool displacement measuring devices of a machine tool including a camera and an illumination device. Space saving can be achieved as compared with the case of measuring the displacement in the direction.

  By providing the reflecting mirror 17 on the first shutter 31, a device for moving the reflecting mirror 17 is not required, and a simple configuration can be achieved.

[Other Embodiments]
In the above description, the tool displacement measuring device 10 of a machine tool including one camera 14, two illumination devices 15 and 16, and one reflecting mirror 17 has been described. However, two cameras, one illumination device, and 1 It is also possible to provide a tool displacement measuring device for a machine tool including two reflecting mirrors.

  In the above description, the tool displacement measuring device 10 for a machine tool including one camera 14, two illumination devices 15 and 16, and one reflecting mirror 17 has been described. It is also possible to provide a tool displacement measuring device for a machine tool that includes a light receiving device, two light projecting devices, and one reflecting mirror.

  In the above, a tool for a machine tool including one camera 14 and two illumination devices 15 and 16 arranged on the same horizontal plane, and a reflector 17 that can be arranged on the same horizontal plane as the camera 14 and illumination devices 15 and 16. Although the displacement measuring device 10 has been described, it includes one camera and two illumination devices arranged on the same vertical plane, and one reflecting mirror that can be arranged on the same vertical plane as the camera and the two illumination devices. It is also possible to use a tool displacement measuring device for a machine tool.

  In the above description, the tool displacement measuring device 10 of a machine tool in which one camera 14 and two illumination devices 15 and 16 are fixed to the base 11 has been described. However, one camera and two illumination devices are supported. It is also possible to provide a tool displacement measuring device for a machine tool that is fixed to the base via a tool.

  In the above description, the tool displacement measuring device 10 of the machine tool including the reflecting mirror 17 provided on the first shutter 31 has been described. However, the light reflection position that reflects the light from the second illumination device 16 toward the camera 14 and the light. It is also possible to provide a tool displacement measuring device for a machine tool provided with a moving device (moving means) that moves the reflecting mirror 17 to a position outside the photographing field of view that is separated from the reflecting position and out of the field of view taken by the camera 14. As the moving device, for example, a lifting device that can move in the Z-axis direction, a horizontal moving device that can move in the XY plane, or the like can be used. Examples of the device include an apparatus including a piston rod having a distal end attached to the support 18 and a cylinder that moves the piston rod forward and backward by supplying and discharging fluid (for example, air, oil, etc.).

  According to the tool displacement measuring device for a machine tool according to the present invention, the displacement of the tip position of the tool can be accurately measured with a simple configuration, so that the accuracy of processing by the tool can be improved, and the manufacturing industry It can be used beneficially.

DESCRIPTION OF SYMBOLS 10 Tool displacement measuring apparatus 11 of a machine tool 11 Base 11a 1st base 11b 2nd base 14 Camera 15 1st illuminating device 16 2nd illuminating device 17 Reflecting mirror 18 Support tool 20 Cover 21 Photographing room 21a First imaging window part 21b Second imaging window 22 First illumination chamber 22a First illumination window 23 Second illumination chamber 23a Second illumination window 24 First communication chamber 25 Second communication chamber 31 First shutter 32 Second shutter 33a ~ 33d Air injection nozzle 41 First measurement region 42 Second measurement region 50 Control device 51 Image processing device A1 Optical axis A2 of first illumination device Camera axis A3 Optical axis T of second illumination device Tool

Claims (4)

A tool displacement measuring device for a machine tool for measuring a displacement of a tip position of a tool of a machine tool,
Photographing means for photographing the tool;
First and second illumination means for irradiating the tool with light;
Reflecting means for reflecting the light;
Moving means for moving the reflecting means;
Image processing means for analyzing the tip position of the tool from the image of the tool photographed by the photographing means,
The first illuminating means is disposed opposite to the photographing means, while the second illuminating means is in the same plane as the first illuminating means and the photographing means and the photographing direction of the photographing means via the reflecting means. Arranged perpendicular to the
When the tool is arranged in a first imaging region between the imaging unit and the first illumination unit, the moving unit moves the reflecting unit to a position away from the imaging field of view of the imaging unit, and One illuminating means illuminates the tool, while the imaging means images the tool;
When the tool is arranged in a second imaging region facing the second illumination means, the moving means moves the reflection means to a position where the light from the second illumination means is reflected to the imaging means side, and While the second illumination means illuminates the tool, the imaging means captures an image of the tool reflected by the reflecting means,
The image processing means measures the tool tip position based on the image of the tool in the first imaging region and the image of the tool in the second imaging region, and measures the tool displacement of a machine tool apparatus. A tool displacement measuring device for a machine tool according to claim 1,
The tool displacement measuring device for a machine tool, wherein the first illuminating means, the second illuminating means, and the photographing means are arranged on the same horizontal plane. A tool displacement measuring device for a machine tool according to claim 1 or 2,
The photographing means, the first illumination means, the second illumination means, the reflection means are covered, the photographing direction by the photographing means, the light irradiation direction by the first and second illumination means, the reflection of light by the reflection means A cover with a window formed in the direction;
A tool displacement measuring device for a machine tool, comprising: a shutter capable of shielding the window. A tool displacement measuring device for a machine tool according to claim 3,
The reflecting means is provided on the shutter;
The tool displacement measuring device for a machine tool, wherein the moving means is the shutter.

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