JP5064344B2 - Robot system - Google Patents

Description

  The present invention relates to a technique for solving a problem caused by a displacement of a cutting tool that occurs when a cutting tool supported on the shaft end of a multiaxial arm is replaced.

As a robot system having a robot that supports a cutting tool at the shaft end of a multi-axis arm, for example, the shaft end of the arm is configured as a rotating shaft, or a rotating shaft is added to this shaft end, and a cutter is attached to this rotating shaft. A burr that supports the blade, moves the cutter blade along the partition line (joint part of the mold) of the workpiece (workpiece) that has been molded, and cuts the burrs generated on the partition line with the cutter blade. A take-off system is known.
In addition, this type of deburring system includes a control device that controls the posture of the cutting tool, and is configured so that the control device can previously store a path along which the cutter blade moves during deburring (so-called teaching). Are also known (see, for example, Patent Document 1 and Patent Document 2).
JP 2008-30251 A JP 2004-148427 A

Generally, the cutter blade is worn and spilled over time, so it can be removed from the rotating shaft and replaced. However, when the cutter blade is replaced, the position of the cutter blade is the same as the teaching position. There is a problem that the machining accuracy is lowered or the teaching data needs to be corrected.
In view of this, usually, a mounting member to which the cutter blade is attached is fixedly provided on the rotating shaft, and a positioning structure such as an engagement groove for positioning the cutting blade of the cutter blade at a predetermined position is provided on the mounting member. It is set as the structure to provide.
However, in this configuration, only a cutter blade that matches the positioning structure of the mounting member can be attached, and a clearance (gap) is required in the positioning structure for attaching and detaching the cutter blade. There is a problem that positioning is impossible.

In addition, when the position of the cutter blade is relatively displaced due to, for example, replacement of the mounting member, even if the position of the cutting edge of the cutter blade is positioned with respect to the mounting member, the position is displaced with respect to the rotational axis. Therefore, after all, there is a problem that the teaching data needs to be corrected. At this time, it may be a problem if the cutter blade is mounted after calibrating the relative displacement between the mounting member and the rotating shaft. For this purpose, a dummy gauge imitating the cutter blade is used in the positioning structure of the mounting member. The calibration is performed by engaging and adjusting the angle of the gauge around the rotation axis of, for example, a flat surface. In order to make this calibration coincide with high accuracy (generally ± 0.5 degrees or less), it is necessary to repeat the detachment and measurement of the gauge, which is a labor-intensive operation.
The various problems described above are not limited to the deburring system, but the cutting tool is supported by the rotating shaft that is the shaft end of the arm or the rotating shaft that is added to the shaft end. This is a problem that commonly occurs in industrial robot systems that perform machining while controlling the surrounding rotation angle.

  The present invention has been made in view of the above-described circumstances, and does not require a structure for positioning the cutting tool with respect to the rotating shaft, and also does not require correction of teaching data when the cutting tool is replaced, An object of the present invention is to provide a robot system capable of suppressing a decrease in machining accuracy.

To achieve the above object, according to the present invention, there is provided a cutter blade comprising a multi-axis arm whose shaft end is configured as a rotating shaft, or a rotating shaft added to the shaft end and a cutting blade for machining a workpiece. Posture control is performed so that the cutting blade of the cutter blade is fed to the workpiece in a predetermined feeding direction according to teaching data that is fixed so as to be rotatable integrally with the rotating shaft along a plane including the rotating shaft and is taught in advance. A rotation means for detecting a shift amount between a position of the cutting edge of the cutter blade around the rotation axis and a reference position around the rotation axis in the teaching data; and rotating the shaft of an amount corresponding the shift amount, or the amount of deviation added to the correction value to correct the angle error of the rotation axis of the shaft end of said arm, switching of the cutter blade about the rotation axis To provide a robot system, characterized in that to correct the position of the blade.

  In the robot system according to the present invention, the detection unit detects the shift amount in a non-contact manner.

According to the present invention, in the robot system described above, the cutter blade and an attachment member that holds the cutter blade and is detachably attached to the rotation shaft are fixedly connected to each other, and the rotation member is attached to the attachment member. A screw portion is provided coaxially with the shaft, and is screwed and fixed to the rotating shaft.

According to the present invention, the amount of deviation between the position of the cutting edge around the rotation axis on which the cutter blade is attached integrally with the rotation and the reference position around the rotation axis in the teaching data is detected, and based on this deviation amount, the rotation axis Since the configuration is such that the position of the cutting edge of the cutter blade is corrected around, a structure for positioning the cutter blade with respect to the rotating shaft is not required, and correction of teaching data when the cutter blade is replaced is also unnecessary. In addition, since the position of the cutting edge is corrected, it is possible to suppress a decrease in machining accuracy.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, a deburring system is exemplified as one aspect of a robot system to which the present invention is applied, but the present invention is not limited to this.
FIG. 1 is a diagram illustrating a configuration of a deburring system 1 according to the present embodiment.
The deburring system 1 includes a jig base 7, a maintenance base 9, and a robot 5 fixedly disposed on a flooring 3, and a control panel 10 that controls the robot 5. A holding mechanism 11 that holds the cutting device 12 is attached to the shaft end (end portion). The cutting device 12 includes a cutter blade unit 14 as an example of a cutting tool.

The flooring 3 constitutes the installation surface of the deburring system 1 and is provided with casters 13 on the back surface so as to be easily movable, and provided with leg members 15 having a height adjusting function. It is configured to achieve high levelness.
The jig base 7 is for fixing a work (workpiece) 37 (FIG. 4), and is configured by fixing a jig 17 for holding the work 37 on the upper surface of a pedestal 19. The jig 17 and the pedestal 19 are configured so as to be flexibly attached and fixed according to the work 37.
The maintenance base 9 is configured by placing a detection unit 21 for detecting an attachment state of the cutter blade unit 14 included in the cutting device 12 on a pedestal 23. When the cutter blade unit 14 is replaced, the detection state of the attachment state of the cutter blade unit 14 is detected by the detection unit 21 prior to the deburring process on the workpiece 37, which will be described later in detail.

The robot 5 is configured as a so-called 6-axis vertical articulated arm type robot, and the arm is movable in the directions of 6 axes J1 to J6. An axis J6 corresponding to the end of the six-axis arm is configured as a rotation axis for rotating the holding mechanism 11.
The control panel 10 includes a controller 10A that controls each joint of the robot 5 and controls the posture of the holding mechanism 11 (cutting device 12). The controller 10A has a function of teaching the position data of the workpiece 37 held on the jig base 7, and the burr 41 (FIG. 4) of the cutting blade 25 (FIG. 3) of the cutter blade unit 14 according to the teaching data. Control is performed to move along the surface of the work 37 where there is.

FIG. 2 is an enlarged view showing the configuration around the axis J6 that is the axis end of the robot 5. As shown in FIG.
A holding mechanism 11 that holds the cutting device 12 is attached to the shaft end portion 27 of the shaft J6 that is the shaft end of the robot 5 so as to rotate integrally around the shaft J6.
The cutting device 12 includes a cutter blade unit 14 and an ultrasonic vibration device 29 that ultrasonically vibrates the cutter blade unit 14.
The ultrasonic vibration device 29 includes a cylindrical housing, and the housing is sandwiched between a pair of semi-circular holding pieces 11A and 11B provided in the holding mechanism 11, and the holding pieces 11A and 11B are connected by bolts. As a result, the ultrasonic vibration device 29 is rotatably held integrally with the holding mechanism 11. The casing of the ultrasonic vibration device 29 is configured to incorporate an ultrasonic vibrator, and the cutter blade unit 14 is fixed to the output shaft (vibration shaft) of the lower surface 29A.

FIG. 3 is an enlarged view showing the cutter blade unit 14 attached to the ultrasonic vibration device 29.
The cutter blade unit 14 includes a cutter blade 33 and a horn (attachment member) 35. The cutter blade 33 constitutes a blade portion of a cutting tool, and in this embodiment, a flat single-edged cutting blade is used as the cutter blade 33. The horn 35 is a member that holds the cutter blade 33 and is attached to the ultrasonic vibration device 29, and a member that transmits the ultrasonic vibration of the ultrasonic vibration device 29 to the cutter blade 33. The horn 35 is also configured as a screw-in type attachment member that is screwed and fixed to the lower surface 29A of the ultrasonic vibration device 29 at the upper end, and the cutter blade 33 is disposed on the lower side of the horn 35, for example. It is fixed and attached integrally.
The cutter blade 33 ultrasonically vibrates in the vibration direction A that is substantially coaxial with the rotation axis of the axis J6 in accordance with the ultrasonic vibration of the ultrasonic vibration device 29, and is substantially the same as the vibration direction A by driving the robot 5. It is moved in the feed direction B, which is a direction orthogonal to each other. A cutting blade 25 is formed in the cutter blade 33 at a location facing the feed direction B.

FIG. 4 is a view showing a mode of deburring by the cutter blade unit 14.
As shown in this figure, at the time of deburring, the robot 5 is moved so that the cutting edge 25 of the cutter blade 33 is applied to the base (root) of the burr 41 formed on the partition line 39 of the workpiece 37. For example, while the cutter blade 33 is vibrated in the vibration direction A with an amplitude of about 30 to 50 μm, the cutter blade 33 is sent along the root of the burr 41 formed on the partition line 39 of the workpiece 37 to cut out the burr 41. .
At this time, the deburring is performed while rotating the cutter blade 33 around the axis J6 so that the cutter blade 33 follows the work surface of the workpiece 37, so that the burr 41 formed on the curved surface can be removed. It has become.

Examples of the molded product that can serve as the workpiece 37 include a nursing bed part, a copying machine part, a tool box, a heat insulating resin box, an automobile air spoiler, an automobile visor, an automobile center pillar, and an automobile interior sheet.
Further, as the work 37, molded products made of various materials such as metal and resin are targeted for deburring, and some of them are hard materials. When deburring a hard molded product, if the force for feeding the cutter blade 33 is weak, the feed of the cutter blade 33 is hindered by the burr 41, and therefore the feed control of the cutter blade 33 by the robot 5 may become unstable. .

Therefore, if the output of the robot 5 is increased and the force for feeding the cutter blade 33 is increased, the stress applied between the cutter blade 33 and the horn 35 of the cutter blade 33 is increased. There is a risk of damage due to failure to withstand.
Similarly, when the vibration frequency of the cutter blade unit 14 is increased or the moving speed is increased to increase the speed of the deburring process, the damage is similarly caused by excessive stress applied between the cutter blade 33 and the horn 35. May occur.
In particular, in the conventional deburring system, the cutter blade 33 is fixed to the horn 35 with bolts, and the cutter blade 33 is detached from the horn 35 and is configured to be replaceable. The strength between 35 was weak and could not withstand high output and high speed.

In contrast, in this embodiment, as described above, the cutter blade 33 is integrally fixed to the horn 35 by brazing or the like, so that the coupling force between the cutter blade 33 and the horn 35 becomes strong and durable. Improves.
Further, a larger stress is applied between the horn 35 and the ultrasonic vibration device 29 than between the cutter blade 33 and the horn 35, and the horn 35 is connected to the ultrasonic vibration device 29, for example, another member such as a bolt or a screw. As long as it is fastened, it cannot withstand high output and high speed.
Therefore, in the present embodiment, the horn 35 is screwed and fixed to the ultrasonic vibration device 29 in a direction substantially perpendicular to the feed direction B (axis J6 direction). In this screw-in structure, a screw portion 36 is integrally provided at the upper end of the horn 35, and the screw portion 36 constitutes a screwing structure. The fastening strength by the threaded portion 36 depends on the diameter of the threaded portion 36, but in the present embodiment, the threaded portion 36 is screwed by expanding the diameter of the threaded portion 36 to substantially the same diameter as the horn 35 configured in a columnar shape. The fastening strength is increased to the maximum, thereby realizing a higher strength than a structure that is fastened by another member such as a bolt or a screw.
With the structure of the cutter blade unit 14 as described above, the strength between the cutter blade 33 and the horn 35 and between the horn 35 and the ultrasonic vibration device 29 is sufficiently increased, and can withstand high output and high speed. A cutting device 12 is obtained.

  In this cutting device 12, since the cutter blade 33 is integrally fixed to the horn 35, when the cutter blade 33 is replaced, the cutter blade unit 14 including the horn 35 is replaced. Therefore, when the cutter blade unit 14 is attached and fixed to the ultrasonic vibration device 29, the horn 35 is screwed and fixed. However, since the cutter blade unit 14 is screwed, the cutting blade 25 of the cutter blade 33 is rotated around the axis J6 after replacement. It is unspecified where it is located.

As described above, the robot 5 includes the posture control means of the cutting device 12 and is configured to be able to teach the position data of the workpiece held on the jig base 7. If the position of the blade 25 is unspecified, the position of the cutting edge 25 at the time of replacement and the reference position around the axis J6 (the zero point position at the time of teaching) will be shifted, and in order to maintain machining accuracy and machining quality It is necessary to perform teaching again.
It is only necessary to improve the coupling structure between the horn 35 and the ultrasonic vibration device 29 and realize a coupling structure in which the cutting blade 25 is positioned at the reference position when the cutter blade unit 14 is replaced. Since strength cannot be maintained by fastening, it is not easy to realize a coupling structure that can obtain strength and positioning without using these screws and bolts, and the coupling structure becomes complicated.

Therefore, in the present embodiment, when the cutter blade unit 14 is replaced, the deburring system 1 is configured to execute a correction mode for correcting a shift at the time of replacement of the cutter blade unit 14 prior to the deburring process. It is said that.
In this correction mode, a deviation amount between the position of the cutting edge 25 of the cutter blade unit 14 and the reference position around the axis J6 is detected, and the cutter blade unit 14 is arranged around the axis J6 so as to eliminate this deviation amount. Correction to rotate is performed.

FIG. 5 is an enlarged view showing the detection unit 21 of the maintenance base 9.
The detection unit 21 detects the amount of deviation between the position of the cutting edge 25 and the reference position around the axis J6 as the mounting state when the cutter blade unit 14 is replaced. The light emitting device 51 and the light receiving device 53. The light emitting device 51 and the light receiving device 53 are arranged to face each other, and the light emitted from the light emitting device 51 is received by the light receiving device 53.
In the correction mode, the cutter blade 33 of the cutter blade unit 14 is disposed in the optical axis C connecting the light emitting device 51 and the light receiving device 53, and the axis J6 is rotated 360 degrees (one rotation). Since the cutter blade 33 has a flat shape, when the axis J6 is rotated once, the projected area (shielding area) of the cutter blade 33 in the light receiving device 53 changes. For example, as shown in FIG. The projection area is minimized in the state B and the state D in which the surface of the cutter blade 33 is parallel to the direction of the optical axis C of the detection unit 21 (P1 and P2 in the figure).

When teaching is performed, the position where the projection area onto the light receiving device 53 is minimized when the cutter blade 33 is arranged in the detection unit 21 is set as the reference position θs of the cutting blade 25, so that in the correction mode, the projection is performed. The rotation angle of the axis J6 rotated until the area is minimized can be detected as the shift amount Δθ.
The change in the projected area in the light receiving device 53 is detected as a change in the amount of received light, and the change in the amount of received light is output to the controller 10A of the control panel 10, and the controller 10A detects the deviation amount Δθ of the cutting edge 25 of the cutter blade unit 14. Is done.

Here, when the cutter blade 33 is a double blade, any one of the cutting blades only needs to face the feed direction B. Therefore, the cutter blade 33 is rotated around the axis J6 by 180 degrees (half rotation), and the projected area is increased. If either one of the minimum positions P1 and P2 is detected, the shift amount Δθ can be detected.
On the other hand, when the cutter blade 33 is a single blade, the cutting blade 25 needs to be securely arranged so as to face the feed direction B. Therefore, as shown in FIG. It is necessary to distinguish and detect the state B facing the side and the state D facing the back side in the figure on the contrary. Therefore, in the present embodiment, this can be distinguished as follows.

  That is, when the cutter blade 33 is rotated once, the projection area is maximized when the surface of the cutter blade 33 is substantially perpendicular to the optical axis C, as shown in FIG. . At this time, by offsetting the light irradiation range 54 between the light-emitting device 51 and the light-receiving device 53 from the axis J6, the projection area in either the state A or the state C is reduced. And state C can be distinguished. The points P1 and P2 can be distinguished from each other according to the rotation direction of the cutter blade 33 with reference to the position Q in the state where the projection area is reduced (state C in the present embodiment), and the displacement relative to the single blade The amount Δθ can be detected.

Moreover, the detection unit 21 is provided with the touch sensor 55 arrange | positioned on the maintenance base 9, as shown in FIG. The touch sensor 55 is for detecting the length of the cutter blade 33. In a reference state, the touch sensor 55 is positioned at a predetermined distance from the touch sensor 55 (hereinafter referred to as a height reference). The blade edge of the cutter blade 33 is adjusted so as to come into contact with the touch sensor 55 when it is arranged at a position).
That is, if the cutting edge of the cutter blade 33 does not come into contact with the touch sensor 55 when the robot 5 is driven in the same manner, it indicates that the protruding amount of the cutting edge of the cutter blade 33 is shorter than the reference, and is separated by a predetermined distance. If the cutting edge of the cutter blade 33 comes into contact with the touch sensor 55 before performing, it indicates that the protruding amount of the cutting edge of the cutter blade 33 is longer than the reference. Such detection is performed by the controller 10A based on the detection signal of the touch sensor 55.

FIG. 7 is a flowchart showing the operation in the correction mode.
In the correction mode, the controller 10A first performs processing for detecting the protrusion amount of the cutting edge of the cutter blade 33. That is, the controller 10A controls each axis of the robot 5, moves the cutter blade unit 14 to the maintenance base 9, and positions the blade edge of the cutter blade 33 directly above the touch sensor 55 (step S1). Next, the controller 10A lowers the cutter blade 33 (step S2), and acquires the coordinate value of each axis of the robot 5 when the cutting edge of the cutter blade 33 comes into contact with the touch sensor 55 (step S3). Then, the controller 10A obtains a difference between the acquired coordinate value and the coordinate value of each axis at the height reference position, and performs correction based on this difference (step S4).

This correction is performed, for example, by correcting teaching data based on a difference in coordinate values. Alternatively, the cutting device 12 may be temporarily removed, and the attachment position of the cutting device 12 may be adjusted up and down so that the difference in step S4 becomes zero.
When the cutter blade unit 14 or the cutting device 12 itself is replaced with a structural mechanism that does not change the protruding amount of the blade edge, the above steps S1 to S4 for correcting the protruding amount are omitted. be able to.

Following the correction of the protrusion amount of the blade edge, the controller 10A controls each axis of the robot 5 and arranges the cutter blade 33 in the optical axis C of the detection unit 21 (step S5). Then, the controller 10A rotates the axis J6 to rotate the cutter blade 33 within the optical axis C (step S6), and detects the rotation angle at which the received light amount is minimized as the deviation amount Δθ (step S7).
At the time of this detection, the controller 10A determines whether or not the projection area increases (the amount of received light decreases) by rotating the cutter blade 33 in one direction. When the projected area increases, to indicate that the projected area is away from the reference position θs, the controller 10A rotates the cutter blade 33 in the reverse direction so that the projected area sequentially decreases, and the projected area starts to increase again. The rotation angle of the point is detected as a deviation amount Δθ.
At this time, detection accuracy can be improved by slowing the rotation speed of the cutter blade 33 at the time of detection.

Next, the controller 10A performs a process of correcting the deviation amount Δθ (step S8).
More specifically, the articulated robot 5 is provided with a drive device such as a servo motor and a rotation angle detection mechanism such as an encoder or resolver for each axis. In general, articulated robots have different values for the origin at the physical angle of the robot arm due to dimensional errors during assembly and mounting error of the rotation angle detection mechanism. And a physical angle error of each axis is corrected based on this value, and a balance (adjustment) is made in advance for all axes.

At this time, in order to specify a certain point in the space, position information (three coordinate points of X, Y, and Z in the orthogonal coordinate system) including three different reference axis directions is necessary. In order to specify the action direction at that point, direction (angle) information (Rx, Ry, Rz in the orthogonal coordinate system) consisting of rotation angles in three axial directions is further required.
In an articulated robot with 6 or more axes, the spatial position of the cutter blade 33 can be controlled with 3 axes among the above 6 parameters (X, Y, Z, Rx, Ry, Rz), so the remaining 3 axes Can be used in the direction of action of the cutter blade 33, and the spatial position designation and the direction of action can be controlled independently.
In this embodiment, in order to control the action direction of the cutting edge 25 of the cutter blade 33 with respect to the workpiece 37, only the axis J6 that controls the action direction is relevant. When the position is displaced, it is only necessary to correct the angle deviation around the axis J6.

As described above, in an articulated robot, generally, correction values for each axis unique to each robot are stored in advance. Therefore, among these correction values, the deviation amount Δθ is included in the correction values around the axis J6. As a new correction value, correction around the axis J6 can be performed (first correction mode).
Apart from this, by rotating the shaft J6 so as to eliminate the deviation amount Δθ, calibration can be performed by matching the position of the cutting edge 25 with the reference position θs (second correction mode).

Then, for example, teaching data is created in advance in a fixed coordinate system such as the base coordinates of the robot 5, and the relative relationship is set with respect to the deviation amount Δθ around the axis J6. If the deviation amount Δθ is corrected, the attitude of the cutter blade 33 (cutting device 12) can be controlled using the same teaching data.
Thereby, since it is not necessary to correct the already input teaching data after replacing the cutter blade unit 14, the time and labor required for calibration after the replacement can be greatly reduced.

Thus, according to the present embodiment, the amount of deviation Δθ of the position of the cutting edge 25 of the cutter blade unit 14 around the axis J6 is detected, and the position of the cutting edge 25 around the axis J6 is detected based on the amount of deviation Δθ. It was set as the structure which correct | amends.
With this configuration, a structure for positioning the cutting edge 25 with respect to the axis J6 is not necessary, and correction of teaching data when the cutter blade unit 14 is replaced becomes unnecessary, and time and labor required for calibration after the replacement. Can be greatly shortened.

Further, according to this embodiment, when correcting the deviation amount Δθ, the cutter blade unit 14 is rotated around the axis J6 so as to eliminate the deviation amount Δθ, and the position of the cutting edge 25 is corrected in accordance with the reference position θs. The configuration.
With this configuration, it is not necessary to rewrite data such as already set correction values with the shift amount Δθ, and calibration can be performed easily.

Further, according to the present embodiment, the cutting edge of the cutter blade 33 is arranged in the optical axis C between the light emitting device 51 and the light receiving device 53, and the light receiving device 53 when the cutter blade 33 is rotated around the axis J6. By detecting the shift amount Δθ based on the received light amount change, the shift amount Δθ is detected in a non-contact manner.
With this configuration, it is possible to easily detect the shift amount Δθ without applying an extra force to the cutter blade 33 during detection.

Further, according to the present embodiment, the cutter blade 33 and the horn 35 that is detachably attached to the ultrasonic vibration device 29 that holds the cutter blade 33 and is fixed integrally with the shaft J6 are fixedly connected to each other. In addition, the horn 35 is screwed and fixed to the ultrasonic vibration device 29 in the same direction as the axis J6.
With this configuration, the strength between the cutter blade 33 and the horn 35 and between the horn 35 and the ultrasonic vibration device 29 is sufficiently increased, and can withstand higher output and higher speed. Further, since the horn 35 is screwed, the cutter blade unit 14 can be easily replaced.

  In addition, embodiment mentioned above shows the one aspect | mode of this invention to the last, and a deformation | transformation and application are arbitrarily possible within the scope of the present invention.

  In the above-described embodiment, a 6-axis multi-joint robot is exemplified as the multi-axis arm type robot, but the present invention is not limited to this. That is, as shown in FIG. 8, a so-called seven-axis robot 105 in which a rotation driving device 61 having a rotation shaft 60 is added to an axis J6 that is an axial end of the arm is configured, and the rotation shaft 60 of the rotation driving device 61 is The holding mechanism 11 may be fixed integrally with the rotation mechanism, and the cutting device 12 may be held by the holding mechanism 11.

In the above-described embodiment, the cutting edge of the cutter blade 33 is disposed between the light emitting device 51 and the light receiving device 53 that are arranged to face each other, and the shift amount Δθ is calculated based on the change in the amount of received light when the cutter blade 33 is rotated. It was set as the structure to detect.
For example, the shaft end (axis J6) of the robot 5 is placed at a predetermined position, the cutter blade 33 is photographed by a photographing device such as a CCD camera, and the contour shape of the cutter blade 33 is recognized by image recognition. It is good also as a structure which calibrates by rotating the cutter blade 33 so that the said contour shape and the contour shape of the cutter blade 33 obtained from the picked-up image when the cutting blade 25 is located in reference | standard position (theta) s may mutually correspond. .

Further, the inclination of the surface of the cutter blade 33 may be detected by a sensor to detect the deviation amount Δθ. Specifically, as shown in FIG. 9A, two points R1 and R2 that are separated from each other by the same distance X / 2 in the opposite direction around the axis J6 are set in the plane of the cutter blade 33. 9B, distances Y1 and Y2 from a certain reference position H to each of the points R1 and R2 are detected by distance sensors 81 and 82, respectively. If the state where the cutter blade 33 is rotated so that the distance Y1 = the distance Y2 is used as a reference during teaching, the deviation amount Δθ is obtained as Arctan [(Y2−Y1) / X].
In addition, instead of providing the distance sensors 81 and 82 for each of the points R1 and R2, as shown in FIG. 9C, the point R1 and R2 can be obtained by one distance sensor 81 by moving the cutter blade 33 by the distance X. The distances Y1 and Y2 may be detected.

Moreover, it is not restricted to the structure which detects deviation | shift amount (DELTA) (theta) by making the cutter blade 33 into a detection target.
That is, when there is a member that rotates or moves integrally with the cutter blade 33 and changes the projected area with respect to the light receiving device 53, for example, the amount of rotation or the amount of movement of the member is detected, thereby indirectly. In particular, the displacement amount Δθ of the cutter blade 33 may be detected.

  In addition, as shown in FIG. 10, when the relative positional relationship of the ultrasonic vibration device 29 is kept constant with respect to the cutting edge 25 of the cutter blade 33, It is also possible to form a light reflecting surface 70 that reflects the light and calibrate by rotating the cutter blade 33 so that the reflected light from the light reflecting surface 70 is detected at the reference position θs. Of course, the light reflecting surface 70 may be formed on the outer periphery of the horn 35.

In the above-described embodiment, the configuration including the ultrasonic vibration device 29 that vibrates the cutter blade unit 14 in the vibration direction A is illustrated as the cutting device 12. However, the configuration is not limited thereto, and the ultrasonic vibration device 29 is provided. Instead, for example, the horn 35 of the cutter blade unit 14 may be screwed and fixed to the shaft end portion 27 of the shaft end.
In the above-described embodiment, the cutter blade unit 14 is screwed and fixed to the ultrasonic vibration device 29 so as to be replaceable. However, the present invention is not limited to this. That is, the cutter blade unit 14 may be firmly fixed to the ultrasonic vibration device 29 by, for example, shrink fitting to constitute the cutting device 12, and when the cutter blade unit 14 is replaced, the entire cutting device 12 may be replaced.

The present invention can be applied not only to the deburring system 1 that cuts the burrs 41 of the workpiece 37 but also to a robot system that performs processing such as cutting and grinding using a cutting tool.
In particular, in a robot system having a configuration in which a cutting tool is fixedly connected to an attachment member that is detachably attached to a rotation shaft and is integrally connected, and the attachment member is screwed and fixed in a direction coaxial with the rotation shaft, the cutting tool and the attachment member In addition, since a strength that can withstand high output is realized between the rotating shafts, it has a great effect on a trimming process for trimming a hard material or a thick material. Examples of processing objects suitable for this trimming include hard materials used as parts for home appliances, interior / exterior parts for automobiles, and parts for spacecraft.

It is a perspective view which shows the structure of the deburring system which is an aspect of the industrial robot which concerns on embodiment of this invention. It is a figure which expands and shows the structure of the axis | shaft J6 periphery which is a shaft end of a robot. It is a figure which expands and shows the cutter blade unit attached to the unit attaching part. It is a figure which shows the aspect of the deburring by a cutter blade unit. It is a figure which expands and shows a maintenance base detection unit. It is a figure which shows an example of the light reception amount change which is a detection result of a detection unit. It is a flowchart which shows operation | movement of correction | amendment mode. It is a figure which shows the other aspect of a robot. It is a figure for demonstrating the other method of deviation | shift amount detection. It is a figure which shows the other aspect of a detection unit.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Deburring system 5, 105 ... Robot, 10A ... Controller, 12 ... Cutting device, 14 ... Cutter blade unit (cutting tool), 21 ... Detection unit, 25 ... Cutting blade, 29 ... Ultrasonic vibration device, 33 ... Cutter blade, 35 ... horn, 36 ... thread, 37 ... workpiece, 39 ... partition line, 41 ... burr, θs ... reference position, Δθ ... deviation amount

Claims (3)

The shaft end of the multi-axis arm is configured as a rotating shaft, or the rotating shaft is added to the shaft end, and the rotating shaft is provided such that a cutter blade having a cutting blade for machining a workpiece is along a plane including the rotating shaft. A robot that is fixed so as to rotate integrally with the robot, and performs posture control to send the cutting blade of the cutter blade to the workpiece in a predetermined feeding direction according to teaching data that has been taught in advance.
Detecting means for detecting a deviation amount between a position of the cutting edge of the cutter blade around the rotation axis and a reference position around the rotation axis in the teaching data;
The axis of rotation of the shaft end of the arm is rotated by the amount of deviation, or the amount of deviation is added to a correction value for correcting the angle error of the axis of rotation of the shaft end of the arm, and the cutter is rotated around the axis of rotation. robot system and correcting the position of the cutting edge of the blade.   The robot system according to claim 1, wherein the detection unit detects the shift amount in a non-contact manner. The cutter blade and an attachment member that holds the cutter blade and is detachably attached to the rotation shaft are fixedly connected to each other, and a screw portion is provided coaxially with the rotation shaft to rotate the attachment member. The robot system according to claim 1 or 2, wherein the robot system is screwed and fixed to a shaft.

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