JP3515023B2 - Measuring method and measuring device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape and surface roughness of a workpiece machined by a machine tool, a mounting position of the workpiece on a machine tool before machining, and a machine tool for the workpiece according to a machining program. The present invention relates to a measuring method and a measuring device that can be used to obtain a movement locus of a rotating main shaft of the.

[0002]

2. Description of the Related Art In order to inspect the shape, surface roughness, etc. of a work piece machined by a machine tool, the work piece has conventionally been removed from the support part of the machine tool, and the object to be measured using a microscope or a contact type measuring device. The positions of a plurality of measurement points on the work piece are obtained, and the shape and surface roughness of the processed surface are obtained from the relative arrangement of the measurement positions.

However, when the work piece is reattached to the support portion of the machine tool after the measurement, it is difficult to completely reproduce the attached state. Therefore, when the required machining accuracy is not obtained. The work had to be discarded without reworking. Further, measurement using a microscope not only requires skill, but is also a difficult task for elderly people with low eyesight. Furthermore, when using a contact type measuring device which measures by contacting a contact with a work piece, if the work piece has burrs or chips, a large resistance acts on the contact piece and accurate measurement cannot be performed.

Therefore, the work piece attached to the supporting portion of the machine tool is photographed by a camera, the photographed image is enlarged and displayed at a high magnification on a monitor, and the position of the measurement point on the work piece is contactlessly displayed. As a result, not only the shape and surface roughness of the work piece but also the presence or absence of burrs and chips are inspected.

[0005]

Conventionally, when the position of a measurement point on a workpiece is obtained using a photographed image displayed by the monitor, the image of the measurement reference point is superimposed on the image of the workpiece by the monitor. The position of the measurement point is specified by displaying the image as a reference and associating the image of the measurement reference point with the measurement point of the workpiece. However, displaying an image of such a measurement reference point complicates the display control of the image. In addition, a dedicated attachment mechanism for attaching the camera to the machine tool is required, which complicates the structure, and a large machine tool requires a troublesome attachment work on the machine. In addition, a cable is required to transmit the image data generated by the camera to the monitor and to supply power to the camera, so that the cable interferes with the work or environment such as a machining site. There was also a risk of cable damage or disconnection below.

It is an object of the present invention to provide a measuring method and a measuring device which can solve the above problems.

[0007]

A measuring method according to the present invention comprises a machining tool mounting portion on a rotary spindle of a machine tool,
An image pickup device including a battery is attached, the image pickup device shoots a workpiece without removing it from a support portion of a machine tool, and image data generated by the image pickup device is transmitted to a monitor through a wireless communication device, The photographed image of the work piece is enlarged and displayed on the monitor, and the rotating spindle is moved relative to the work piece, so that the measurement point of the work piece that is enlarged and displayed on the monitor is displayed on the monitor screen. It is arranged at a position corresponding to the integrated fixed point instruction mark, and based on the relative movement direction and the relative movement amount from the set reference position for the workpiece of the rotating spindle,
The feature is that the position of the measurement point is obtained.

In the measuring method of the present invention, first, the rotary spindle is moved relative to the workpiece to measure the workpiece enlarged and displayed on the monitor while being attached to the support portion of the machine tool. The point is placed at a position corresponding to the fixed point instruction mark indicating the fixed point on the monitor screen. As a result, the rotary spindle is positioned with respect to the measuring point, so the position of the measuring point can be obtained in a non-contact manner based on the relative movement direction and the relative movement amount of the rotating spindle from the set reference position with respect to the workpiece. You can Since the fixed point instruction mark is integrated on the screen of the monitor, it is not necessary to display the mark for specifying the measurement point of the workpiece as an image, and the display control does not become complicated. Further, since the image pickup device is detachably attached to the tool attachment portion of the rotary spindle of the machine tool, a dedicated attachment mechanism is unnecessary and the structure is simplified. Further, since the image pickup device includes a battery and transmits the image data to the monitor via the wireless communication device, a cable for transmitting the image data to the monitor and supplying power to the image pickup device is unnecessary,
Workability can be improved.

The measuring device of the present invention comprises an image pickup device which is attachable to and detachable from a tool mounting portion of a rotary spindle of a machine tool, a transmitter which is integrated with the image pickup device, and a receiver which is connected to a monitor. The wireless communication device, the battery included in the image pickup device, and the fixed point instruction mark integrated on the screen of the monitor, and the image pickup device attached to the tool attachment portion are attached to the support portion of the machine tool. The image data generated by the imaging device is arranged at a position where the image of the processed object is captured, and the wireless communication device can transmit the image data to the monitor. The measurement point of the work piece magnified and displayed on the monitor can be enlarged by the fixed point finger by the relative movement of the rotating spindle to the support part. Characterized in that it is can be arranged at a position corresponding to the mark. The measuring apparatus of the present invention can carry out the method of the present invention.

In the measuring device of the present invention, the machine tool has means for detecting the relative movement direction and the relative movement amount of the rotary spindle relative to the support portion from the set reference position, and the relative movement direction from the reference position. It is preferable that the detected value of the relative movement amount can be displayed on the monitor.
Thereby, the position of the measurement point of the workpiece can be obtained with the machine accuracy of the machine tool.

The machine tool has an automatic tool changer,
It is preferable that the image pickup device can be attached to and detached from the tool attachment portion of the rotary spindle by the automatic tool changer.
As a result, the image pickup device can be automatically attached to and detached from the tool attachment portion of the rotary spindle.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A machine tool 1 shown in FIG. 1 includes a bed 2 installed on a floor, a base 3 movably supported by the bed 2 in one horizontal axis direction (hereinafter, X axis direction), and A table (workpiece support part) 4 movably supported by a base 3 in one horizontal axis direction orthogonal to the X axis direction (hereinafter referred to as Y axis direction), and a column 5 attached to the bed 2 in the vertical axis direction. The processing head 6 is supported so as to be movable in the following (Z-axis direction).

The base 3, table 4, processing head 6
Are driven by a drive mechanism controlled by the CNC device 7. For example, a servomotor for driving a ball screw which is screwed to a ball nut attached to the base 3 and is supported by the bed 2, and a servomotor for driving a ball screw attached to the table 4 and which is supported by the base 3 are screwed. The ball screw driving servomotor and the ball screw driving servomotor screwed to the ball nut attached to the machining head 6 and supported by the column 5 are rotated by a pulse sent from the CNC device 7. When driven, the base 3 moves in the X-axis direction, the table 4 moves in the Y-axis direction, and the machining head 6 moves in the Z-axis direction by a distance corresponding to the number of pulses. Further, the CNC device 7 has an operating device 8 for manually moving the base 3, the table 4, and the processing head 6 by an operator. The operation device 8 includes a manual operation dial 8a and an axis selection switch 8
It is possible to move the base 3, the table 4, or the machining head in the axial direction selected by the axis selection switch 8b including b and by a pulse amount according to the rotation amount of the manual operation dial 8a.

The machining head 6 includes a housing 11 and
The housing 11 includes a rotary main shaft 12 rotatably supported around the Z axis, and a main shaft motor 16 that rotationally drives the rotary main shaft 12. The main shaft motor 16 is a CNC.
It is controlled by the device 7. A tool attachment portion 12a is provided on the end surface of the rotary spindle 12. The tool mounting portion 12a has a tapered concave portion on the inner surface, and the machining tool 14 is held by a holder 13 having a tapered portion fitted in the concave portion, so that the machining tool 14
Is attached to the tool attachment portion 12a. A known structure can be adopted for the holding mechanism of the holder 13 provided in the processing head 6 and the holding mechanism of the tool 14 by the holder 13. The type of the processing tool 14 is not particularly limited,
For example, a cutting tool such as a milling cutter or an end mill, a drilling tool such as a drill, a grinding tool such as a grindstone, and a polishing tool such as a buff that holds an abrasive can be attached to the rotary spindle 12.

The machine tool 1 has an automatic tool changer 15 composed of a tool magazine 15a attached to the column 5 and a tool change arm 15b.
The tool 14 mounted on the tool mounting portion 12a of the rotary spindle 12 can be automatically replaced together with the holder 13 by being controlled by. The automatic tool changer 15 may have a known structure.

The workpiece W is attached to the table 4 and is rotated by controlling the drive mechanism of the base 3, the table 4, the machining head 6, the spindle motor 16 and the automatic tool changing device 15 by the CNC device 7 based on the machining program. The workpiece W can be processed by the tool 14 attached to the tool attaching portion 12a of the spindle 12.

Further, the X-axis direction movement distance detection sensor of the base 3 attached to the machine tool 1, the Y-axis direction movement distance detection sensor of the table 4, and the Z-axis direction movement distance detection sensor of the machining head 6 are provided in the CNC device 7. Connected, which allows
The relative movement amount of the rotary spindle 12 from the preset reference position with respect to the table 4 can be detected. The reference position can be set arbitrarily, and for example, the machine origin of the machine tool 1, the processing origin set when processing the workpiece W, or another arbitrary position can be set as the reference position. Further, feedback control is performed in order to improve the position accuracy when the base 3, the table 4, and the processing head 6 are driven based on the signals from the respective movement distance detection sensors. A known structure can be used for the detection of the relative movement amount by the movement distance sensor and the feedback control.

A tool mounting portion 12a of the rotary spindle 12
An imaging device 21 that constitutes the measuring device 20 is detachably attached to the. The image pickup device 21 is (1) in FIG.
As shown in (2), a main body 21a, a photographing lens system 21b for converging light incident from a lower end opening 21a 'of the main body 21a, and an illumination light source 21c arranged around the opening 21a'. Have and. As the light source 21c, it is preferable to use an ultra-high brightness LED having a long life. Its body 2
1a, a CCD for generating image data by photoelectrically converting light incident from the lens system 21b, and an imaging device 2
1 and a battery for operating the transmitter of the wireless communication device 22 are incorporated. In the present embodiment, the lens system 2 of the image pickup device 21 attached to the tool attachment portion 12a.
The optical axis of 1b and the axis of the rotary main shaft 12 coincide with each other. On / off switch 2 for operation is provided outside the main body 21a.
1d, operation confirmation lamp 21e, image signal output cable connection port 21f, and image brightness adjustment switch 21g
A color adjustment switch 21h and a battery charging cable connection port 21i. The type of the image pickup device 21 is not particularly limited. For example, an image pickup device other than a CCD may be used, or other functions such as a scale function and image adjustment may be provided, and the configuration of the lens system is also particularly limited. Not done. Also, the battery is not particularly limited, and for example, a nickel hydrogen battery can be used.

The tool mounting portion 12a of the image pickup device 21
For attachment to the main body 21a of the processing tool 14
A connecting portion 21k similar to the shank portion is provided. The connecting portion 21k is similarly held by the holder 13 similar to that for holding the machining tool 14. As a result, the image pickup device 21 causes the tool attachment part 12 via the holder 13.
It can be attached to and detached from a. In this embodiment, the axis of the connecting portion 21k is the same as the axis of the rotary main shaft 12 and the lens system 21b.
Coincides with the axis of.

The same holder 13 is used for the tool 14 and the image pickup device 21, and the image pickup device 21 includes a battery and transmits image data generated by photographing by the wireless communication device 22 as described later. From that,
It is not necessary to connect the cable to the image pickup device 21. Therefore, the image pickup device 21 can be attached to and detached from the tool attachment portion 12a by the automatic tool changing device 15. That is, the imaging device 21 is attached to and detached from the tool attaching portion 12a by the arm 15b of the automatic tool changing device 15 similarly to the machining tool 14, and is also stored in and taken out from the magazine 15a.

A transmitter constituting a radio communication device 22 is integrated with the image pickup device 21, and an antenna 22 of the transmitter is provided.
a projects from the main body 21a. As shown in FIG. 3, the receiver 22b constituting the wireless communication device 22 is a monitor 2
3 is connected. A commercially available home-use television may be used as the monitor 23. Its transmitter and receiver 22
As the antennas 22a and 22c of b, commercially available antennas can be used. The imaging device 21 attached to the tool attachment portion 12a is arranged at a position where the workpiece W attached to the table 4 can be imaged. As a result, the image data generated by the imaging device 21 is transmitted to the monitor 23 by the wireless communication device 22, and the captured image of the workpiece W corresponding to the image data can be enlarged and displayed on the monitor 23. There is. The magnification is, for example, about 400 times. Note that the structure of the wireless communication device 22 is not particularly limited, and a known device can be used.

Further, the monitor 23 displays the relative movement direction and the relative movement amount of the rotary spindle 12 from the predetermined reference position with respect to the table 4 based on the detection values by the respective movement distance detection sensors. That is, based on the detection value of the X-axis direction movement distance detection sensor of the base 3,
“X” is displayed as the relative movement direction, the X-axis direction movement distance of the base 3 from the processing origin is displayed as the relative movement amount, and based on the detection value of the Y-axis direction movement distance detection sensor of the table 4, "Y" is displayed as the relative movement direction, the Y-axis direction movement distance of the table 4 from the processing origin is displayed as the relative movement amount, and based on the detection value of the Z-axis direction movement distance detection sensor of the processing head 6, the “Z” is displayed as the relative movement direction, and the Z-axis direction movement distance of the table 4 from the processing origin is displayed as the relative movement amount.

In the present embodiment, the monitor 23 is used exclusively for displaying the image picked up by the image pickup device 21, but the monitor 7a of the CNC device 7 is replaced by the receiver 22.
Alternatively, the monitor 7a may display an image captured by the imaging device 21 and a relative movement direction of the rotary spindle 12 with respect to the table 4 from a predetermined reference position, and a detected value of the relative movement amount.

As shown in FIG. 3, a fixed point instruction mark 30 for instructing a fixed point on the screen of the monitor 23 is integrated on the screen. The fixed point instruction mark 30 is
In this embodiment, it is formed by printing on a transparent sheet that is attached to the outer surface of the screen of the monitor 23 with an adhesive, and the center position of the screen is designated as a fixed point by the cross shape. The measurement point of the workpiece W displayed by the monitor 23 can be arranged at a position corresponding to the fixed point instruction mark 30 by the relative movement of the rotary spindle 12 with respect to the table 4. The shape of the fixed point instruction mark 30 and
The number and positions of fixed points on the screen are not particularly limited, and a plurality of positions other than the central position may be designated as fixed points. In addition, as shown in FIG.
The dimensional measurement scale 31 formed with 0 is the monitor 2
It may be integrated into the three screens.

For example, as shown in FIG. 5, when measuring the surface roughness of the machined surface d of the workpiece W orthogonal to the X-axis direction, it is mounted on the tool mounting portion 12a of the rotary spindle 12 of the machine tool 1. After the workpiece W is processed by the processing tool 14, the imaging device 21 is attached to the tool attachment portion 12a in place of the processing tool 14. The automatic tool changing device 15 can change the tool 14 to the image pickup device 21. Next, the workpiece W is photographed without being removed from the table 4. Thereby, the image data generated by the imaging device 21 is transmitted to the monitor 23 via the wireless communication device 22, and the captured image of the workpiece W is enlarged and displayed on the monitor 23. Next, by moving the rotary spindle 12 relative to the workpiece W, the bottom of one concave portion on the machining surface d enlarged and displayed by the monitor 23 corresponds to the fixed point instruction mark 30 as a measurement point d ′. Then, the rotary spindle 12 is positioned with respect to the measurement point d '. Further, by moving the rotary spindle 12 relative to the workpiece W, the peak of one convex portion on the processing surface d is made to correspond to the fixed point instruction mark 30 as another measurement point d ″, and rotation with respect to the measurement point d ″ is performed. The spindle 12 is positioned. At this time, the relative movement direction of the rotary spindle 12 with respect to the workpiece W can be selected by the axis selection switch 8b of the operation device 8, and the relative movement amount can be set according to the rotation amount of the manual operation dial 8a. Workpiece W of the rotary spindle 12
The relative movement direction and the relative movement amount with respect to are displayed on the monitor 23. The positions of both measurement points d'and d "are determined in a non-contact manner based on the relative movement direction and relative movement amount of the rotary spindle 12 from the reference position with respect to the workpiece W. For example, the measurement point d'is a fixed point. The detected value Xa of the relative movement amount in the X-axis direction from the machining origin of the rotary spindle 12 with respect to the table 4 when corresponding to the instruction mark 30 and the other measurement point d ″ are associated with the fixed point instruction mark 30. The detected value Xb of the relative movement amount of the rotary spindle 12 with respect to the table 4 in the X-axis direction from the processing origin is obtained as the positions of both measurement points d ′ and d ″. The difference between Xb and the detected value Xb of the other measurement point d'is one of the data for obtaining the surface roughness of the machined surface d.

According to the above configuration, since the fixed point instruction mark 30 is integrated on the screen of the monitor 23, it is not necessary to display the mark for specifying the measurement point of the workpiece W as an image, and the display control is performed. Does not get complicated. In addition, the image pickup device 21 includes a tool attachment portion 12 of the rotary spindle 12.
Since it is attached to a, a dedicated attachment mechanism is unnecessary and the structure is simple. Further, since the image pickup device 21 includes a battery and transmits image data to the monitor 23 via the wireless communication device 22, the image data monitor 2 can be used.
A cable for transmission to the image pickup device 3 and power supply to the image pickup device 21 is not necessary, and workability can be improved. Further, by displaying the detected values of the relative movement direction and the relative movement amount of the rotary spindle 12 from the preset reference position with respect to the table 4 on the monitor 23, the measurement point of the workpiece W can be measured with the machine accuracy of the machine tool 1. The position of can be calculated. Further, the automatic tool changer 15 allows the image pickup device 21 to be automatically attached to and detached from the tool attachment portion 12a.

As shown by a chain double-dashed line in FIG. 2, a main body 21a of the image pickup device 21 is provided with a second connecting portion 21k 'having an axis perpendicular to the axis of the connecting portion 21k.
The image pickup device 21 is attached to the tool attachment part 12a via the second connecting portion 21k ', and the taking lens system 21b of the image pickup device 21 is used.
The optical axis may be attached so that it is orthogonal to the axis of the rotary main shaft 12. Accordingly, by moving the rotary spindle 12 relative to the workpiece W in the direction parallel to the plane including the Z axis, the measurement point on the machining surface of the workpiece W parallel to the horizontal plane corresponds to the fixed point instruction mark. It becomes possible to obtain the position of the measurement point by arranging it at the position where Further, the image pickup device 21 may be attached to the tool attaching portion 12a via a universal joint so that the optical axis direction of the taking lens system 21b can be positioned in an arbitrary direction.

The present invention is not limited to the above embodiment. For example, the structure of the machine tool is not limited to the above-described embodiment, and the one in which the rotary spindle is driven to rotate about the horizontal axis, or the rotary spindle with respect to the pointing portion of the workpiece is centered around the X, Y, and Z axes. It may be relatively movable in the rotating direction. What is obtained using the present invention is not limited to the surface roughness of the workpiece,
For example, even after obtaining the shape of the workpiece after machining, the presence or absence of burrs and chips, the mounting position of the workpiece on the support part before machining, the movement trajectory of the rotating spindle of the machine tool with respect to the workpiece by the machining program, etc. Good. The fixed point instruction mark is not limited to one formed by printing on a transparent sheet that is attached to the screen of the monitor with an adhesive, and may be, for example, one engraved on the outer surface glass of the monitor screen. Anything that can be integrated into the screen without being used. Power may be supplied to the transmitter of the imaging device and the wireless communication device via the AC adapter when the battery is exhausted. The present invention can also be applied to the determination of the position of a measurement point on a workpiece machined by the laser machining device in a compound machine tool having a laser machining device as well as a rotary spindle. The imaging device can be mounted not only on the rotating spindle of the machine tool, but also on an electric discharge machine, a cylindrical grinder, a surface grinder, etc. via a magnet stand, etc., or by mounting it on a table stand, the shape of blades, grindstones, materials It may be used for inspections such as. It is also possible to display the photographed image of the workpiece by the photographing device of the present invention and the designed finished product image on the monitor of the computer system constituting the CAD so as to confirm the completion degree of the machining. Further, the CAM is linked with the measurement result by the measuring device of the present invention.
Change machining conditions and machining contents in the system, input / output of machining data, repetition number of machining program and C
The data of the NC device may be changed.

[0029]

According to the present invention, when a photographed image of a workpiece is enlarged and the position of a measurement point is obtained, complicated display control, a dedicated mounting mechanism for an image pickup device, for photographing and image transmission. It is possible to provide a measuring method and a measuring device which can improve the workability and facilitate the attachment and detachment of the imaging device without using the cable.

[Brief description of drawings]

FIG. 1 is a front view of a measuring device and a machine tool according to an embodiment of the present invention.

2A and 2B are a front view and a bottom view showing a lens system and a light source, respectively, of the imaging device in the measuring device according to the embodiment of the present invention.

FIG. 3 is a front view of a monitor in which a fixed point instruction mark is integrated in the measuring apparatus according to the embodiment of the present invention.

FIG. 4 is a front view of a fixed point instruction mark of a modified example of the measuring apparatus according to the embodiment of the present invention.

FIG. 5 is an operation explanatory view of the measuring device according to the embodiment of the present invention.

[Explanation of symbols]

1 machine tool 4 table (support) 12 rotating spindle 12a Tool mounting part 15 Automatic tool changer 21 Imaging device 22 wireless communication device 23 Monitor 30 Fixed point instruction mark W Workpiece

Claims (4)

(57) [Claims] 1. An image pickup device including a battery is attached to a mounting portion of a machining tool on a rotary spindle of a machine tool, and an image of the workpiece is photographed by the image pickup device without being detached from a support portion of the machine tool. By transmitting the image data generated by the device to the monitor via the wireless communication device, the captured image of the work piece is enlarged and displayed on the monitor, and the rotation spindle is relatively moved with respect to the work piece. The measurement point of the work piece magnified by the monitor is placed at the position corresponding to the fixed point indication mark integrated on the monitor screen, and the relative movement of the rotating spindle from the set reference position with respect to the work piece. A measuring method characterized in that the position of the measuring point is obtained based on the direction and the relative movement amount. 2. A wireless communication device comprising an image pickup device attachable to and detachable from a tool attachment portion of a rotary spindle of a machine tool, a transmitter integrated with the image pickup device, and a receiver connected to a monitor. A battery included in the imaging device,
With a fixed point instruction mark integrated on the screen of the monitor, the imaging device attached to the tool attachment portion is arranged at a position where the workpiece attached to the support portion of the machine tool can be imaged, The image data generated by the imaging device can be transmitted to the monitor by the wireless communication device, and the photographed image of the workpiece corresponding to the image data can be enlarged and displayed on the monitor, and the rotation spindle for the support portion can be displayed. The measuring device is characterized in that the measuring point of the work piece enlarged and displayed by the monitor can be arranged at a position corresponding to the fixed point instruction mark by the relative movement of the. 3. The machine tool has means for detecting a relative movement direction and a relative movement amount of a rotary spindle relative to the support portion from a set reference position, and detects a relative movement direction and a relative movement amount from the reference position. The measuring device according to claim 2, wherein the detected value can be displayed by the monitor. 4. The measuring device according to claim 2, wherein the machine tool has an automatic tool changer, and the image pickup device is attachable to and detachable from the tool attachment part of the rotary spindle by the automatic tool changer. .