JP2005313254A - Axial aligning method and device, and axial aligning tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide axial aligning method and device for highly accurately aligning an axis of a positionable movable shaft to face a rotatable rotary shaft at a fixed position. <P>SOLUTION: This method relates to aligning of the axis of the movable shaft 13 in relation to the axis of the rotatable rotary shaft 3 at the fixed position. After positioning the movable shaft 13 to a prescribed position set in advance in relation to the axis of the rotary shaft 3, the movable shaft 13 is moved in prescribed one direction from the prescribed position, and a first position for detecting a part 17 to be detected provided on the movable shaft 13 by a sensor 15 attachably/detachably mounted on the rotary shaft 3 is measured. The rotary shaft 3 is rotated by 180°, the movable shaft 13 is moved in the direction opposite to the prescribed one direction, and a second position for detecting the part 17 to be detected provided on the movable shaft 13 by the sensor 15 is measured. Based on position data of the measured first and second positions, deviation amount of the prescribed position of the movable shaft 13 in relation to the axis of the rotary shaft 3 is calculated. In this method and device, the axis of the movable shaft 13 is aligned in relation to the axis of the rotary shaft 3 based on the arithmetic result. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an axis of a handling robot that feeds and unloads a workpiece with respect to an axis of a spindle in a machine tool such as a lathe, and an axis of a tool provided in a tool post provided facing the spindle. The present invention relates to a method and apparatus for aligning shafts, and a centering jig used in the centering method, and more specifically, a shaft center using the centering jig that can be easily attached to and detached from the end of the main shaft. The present invention relates to an alignment method and apparatus.

  For example, in a machine tool such as a lathe, a workpiece is attached to and detached from a chuck provided on a spindle using a handling robot, and is mounted on a tool post that is movably provided facing the spindle. The workpiece is cut by a cutting tool.

  As described above, when a workpiece is attached to or detached from the chuck using a robot, the workpiece is attached or detached while the axis of the chuck (spindle) and the axis of the robot hand holding the workpiece are aligned. is there. Further, when the workpiece held by the chuck provided on the spindle is to be cut with a cutting tool provided on the tool post, a position where the axis of the spindle and the axis of the cutting tool coincide with each other is set as a reference position, for example. For example, it is necessary to set a reference position in advance.

  Even when the reference position is adjusted in advance so that the axis of the spindle and the axis of the robot hand or the axis of the spindle and the axis of the cutting tool mounted on the tool post coincide with each other, There may be a slight deviation in the reference position due to the passage of usage time or ambient temperature change. Therefore, in order to perform high-precision machining, the deviation of the reference position, that is, the deviation between the axis of the spindle and the axis of the robot hand or the deviation between the axis of the spindle and the axis of the cutting tool is measured. Need to be corrected.

  By the way, there is Patent Document 1 as a prior example for detecting and correcting the deviation of the axis between the axis of the main axis and a separate main axis that can face the main axis.

  Patent Document 1 discloses a technical configuration as follows. That is, as shown in FIG. 4, a guide bush whose axial center coincides with the axial center of the main shaft 100 on the front side (right side in FIG. 4) of the main shaft 100 provided on the main shaft so as to be rotatable and movable in the Z-axis direction. 101 is a cutting tool (not shown) for cutting the bar material 103 guided by the guide bush 101 on a tool post 102 which can be moved and positioned in the X and Y axis directions orthogonal to the Z axis. ) And an outer diameter measuring device 104 for detecting the axial center position of the bar member 103.

  A back spindle 105 arranged on the front side facing the spindle 100 and the guide bush 101 is provided so as to be movable and positionable in the Z-axis direction and the X-axis direction. A back main shaft 107 capable of gripping the bar member 103 is rotatably mounted, and a tool unit 110 holding a processing tool 109 for processing the bar material 103 is mounted.

  In the above-described configuration, when the shaft center of the main shaft 100 (guide bush 103) is positioned so that the shaft center of the back main shaft 107 coincides, detection of a slight deviation amount of both shaft centers is performed as follows. It has been broken.

  That is, the bar material 101 held on the main shaft 100 is cut to a predetermined outer diameter by a cutting tool provided on the tool post 102, and then gripped by the rear main shaft 107 and cut off by a parting tool. Thereafter, the bar material 103 held on the main shaft 100 is cut again to the same outer diameter.

  Thereafter, the tool post 102 is moved in the X and Y axis directions, and the outer diameter measuring device 104 provided in the tool post 102 is used to measure the outer diameter of the bar material 103 to determine the axial center position. Next, after the main shaft 100 is retracted and the bar material 103 is retracted, the bar material 103A held by the rear main shaft 107 is moved to a position corresponding to the outer diameter measuring instrument 104 (the rear main shaft 107 is the first bar material). The outer diameter measuring device 104 measures the outer diameter to determine the axial center position.

Then, by comparing the position where the shaft center of the bar material 103 is indexed with the position where the axis center of the bar material 103A is indexed, the axial center of the back main shaft 107 with respect to the shaft center of the main shaft 100 and the guide bush 101 is very small. The amount of misalignment can be calculated. A minute shift amount of the shaft center when the shaft center of the machining tool 109 is positioned so as to coincide with the shaft center of the main shaft 100 can also be calculated by the method according to the above description.
JP-A-11-309647

  In the configuration as described above, since the tool rest 102 is provided with the outer diameter measuring device 104, it is possible to automatically detect a slight deviation amount between the axis of the main spindle 100 and the axis of the rear main spindle 107. it can. However, there is a problem that the outer diameter measuring instrument 104 occupies a part of the tool rest 102 and the number of machining tools to be mounted is reduced.

  Further, the outer diameter measuring device 104 must be separately provided for each lathe, and it is difficult to apply to existing lathes. Further, the axial position of the main spindle 100 and the axial position of the rear main spindle 107 Therefore, there is a problem in improving efficiency.

  The present invention has been made in view of the above-described problems, and an axis of a movable shaft that is movable in a direction orthogonal to an axis of a fixed-position rotating shaft that is rotatable at a fixed position is the fixed-position rotating shaft. A centering method for aligning with the axis of the fixed position, wherein the movable shaft is moved to a predetermined direction from the predetermined position after positioning the movable shaft to a predetermined position facing the axis of the fixed-position rotating shaft. Then, a first position at which a detected portion provided on the movable shaft is detected by a sensor detachably attached to the fixed position rotating shaft is measured, and then the fixed position rotating shaft is rotated 180 ° and the movable shaft is rotated. Is moved in the opposite direction of the one direction, the second position is detected by the sensor to detect the detected portion provided on the movable shaft, and the fixed position is determined based on the measured position data of the first and second positions. The predetermined position of the movable shaft with respect to the axis of the rotating shaft It calculates the shift amount, and is characterized in that aligning the axis of the movable shaft with respect to the axis of the fixed position rotation axis based on the calculation result.

  According to the present invention, in the above shaft alignment method, the sensor is positioned between the first and second positions by rotating the fixed position rotating shaft, and the detected shaft provided on the movable shaft by the sensor. A third position at which the movable portion is detected is measured, and position data of the third position is used for calculating a deviation amount of the predetermined position of the movable shaft with respect to the axis of the fixed-position rotating shaft. .

  The present invention also provides a shaft rotation control unit for controlling the rotation of a fixed position rotating shaft that is rotatable at a fixed position, and a movable shaft that can move to a predetermined position facing the end surface of the fixed position rotating shaft. A movable shaft movement control unit for controlling, a sensor detachable from an end of the fixed position rotating shaft, and the movable shaft by the sensor positioned at the first and second positions by the rotation of the fixed position rotating shaft; The amount of deviation of the predetermined position of the movable shaft with respect to the axis of the fixed-position rotating shaft is calculated and corrected based on the first and second measurement position data when detecting the detected portion provided in And a correction calculation unit.

  The present invention also provides a mounting base that can be attached to and detached from an end of a fixed position rotating shaft that is rotatable at a fixed position, a first arm that can be rotated about the axis of a support shaft provided in the mounting base, A second arm rotatable about an axis of a support shaft and an axis perpendicular to a longitudinal direction of the first arm; and provided at a distal end side of the second arm, the fixed position rotation And a sensor capable of detecting a movable shaft movable in a direction perpendicular to the axis of the shaft.

  According to the present invention, a sensor is attached to the end of the fixed-position rotating shaft that is rotatable at a fixed position, and the positions of a plurality of positions of the movable shaft that are positioned so as to coincide with the axial center of the fixed-position rotating shaft are measured with the sensor. Thus, it is possible to easily detect a slight shift amount of the axis of the movable shaft with respect to the axis of the fixed-position rotating shaft. The sensor is detachable with respect to the fixed position rotating shaft, and can be used by being mounted on the fixed position rotating shaft at a completely different position.

  Referring to FIG. 1, for example, a support base 1 corresponding to a headstock in a machine tool such as a lathe is supported by a fixed position rotating shaft (spindle) 3 that is rotatable at a fixed position supported by the support base 1. Has been. This fixed-position rotating shaft 3 corresponds to a main shaft in a lathe and includes a chuck 5 such as a scroll chuck that can grip a workpiece, and is rotationally controlled by driving a control motor 7 such as a servo motor. It is.

  The control motor 7 is controlled and rotated under the control of a control device 9 such as an NC device. The rotation position of the rotation shaft in the control motor 7, that is, the fixed position rotation shaft (hereinafter referred to as the rotation shaft). ) The rotational position 3 can be detected by a rotation detector (not shown) such as a rotary encoder.

  A movable table 11 is provided which can be moved and positioned to a position facing the end surface of the rotating shaft 3, that is, the front surface of the chuck 5. The moving table 11 corresponds to a tool turret such as a turret tool post or a comb tooth tool post in a lathe or a robot hand in a handling robot. A control motor (not shown) is controlled and driven under the control of the control device 9. By doing so, it can be moved and positioned in the X-axis direction, the Z-axis direction, or in the X, Y, and Z-axis directions.

  The movable table 11 supports a movable shaft 13 whose axis can be aligned with a position coinciding with the axis of the rotary shaft 3. The movable shaft 13 corresponds to a tool mounting portion on which a cutting tool can be freely mounted when the movable table 11 corresponds to a tool rest. When the movable table 11 corresponds to a movable portion of a robot in a handling robot for supplying and unloading a workpiece to and from the chuck 3, the movable shaft 13 corresponds to a robot hand.

  The movable shaft 13 includes a detected portion 17 that is detected by a sensor 15 that is detachably attached to the end of the rotating shaft 3, that is, the chuck 5. When the movable shaft 13 corresponds to a tool mounting portion, the detected portion 17 corresponds to a circular portion of the outer periphery such as a spindle, socket, chuck or tool spindle to which a tool can be freely attached. is there. When the movable shaft 13 corresponds to a robot hand, the detected portion 17 corresponds to a cylindrical workpiece or sample held by the robot hand.

  The sensor 15 is a contact sensor or a proximity sensor whose output changes according to a change in the distance between the sensor 15 and the detected portion 17, and is detachable from the chuck 5, that is, the end of the rotary shaft 3. It is supported by the axis alignment jig 19.

  That is, the axis alignment jig 19 includes a mounting base 21 (see FIG. 3) that can be attached to and detached from the end (front surface) of the chuck 5. The mounting base 21 comprises a magnet stand and can be easily attached to and detached from the front surface of the chuck 5. The mounting base 21 is provided with a support shaft 23, and the base end side of the first arm 25 is attached to the support shaft 23 so as to be rotatable about the axis.

  That is, a fitting hole 27 into which the support shaft 23 can be fitted is formed on the base side of the first arm 25, and a slit 29 opened on the distal end side of the first arm 25 is formed in the fitting hole 27. Is connected. The first arm 25 is provided with a fastening tool (not shown) such as a fastening bolt for fastening the slit 29 and fastening the support shaft 23 by the fitting hole 27.

  The first arm 25 includes a second arm 33 having a mounting hole 31 as an example of a sensor mounting portion for mounting the sensor 15. The second arm 33 includes a shaft center of the support shaft 23 and a longitudinal direction of the first arm 25. It is attached so that it can be rotated and fixed around an axis in a direction perpendicular to the axis. That is, the second arm 33 is attached to the first arm 25 by a fixture 35 such as a lock bolt that can be tightened by the sensor 15 through the attachment hole 31.

  The fixing tool 35 is screwed into a screw hole formed in the first arm 25 and tightened with a screw part provided at the tip, thereby tightening a slit 37 formed in the second arm 33 to fix the sensor 15 to the second. In addition to being able to be fixed to the arm 33, the second arm 33 can be fixed to the first arm 25.

  With the above configuration, when the mounting base 21 is attached to the end surface (front surface) of the chuck 5 so that the detection portion 15A of the sensor 15 is directed to the axis 5S (see FIG. 1) of the chuck 5, the detection of the sensor 15 is performed. When the directing direction of the portion 15A is slightly shifted, the mounting base 21 is reattached, or the first arm 25 is pivotally adjusted around the axis of the support shaft 23 and the axis of the fixture 35 is rotated. Further, by rotating the second arm 33, the detection unit 15 </ b> A of the sensor 15 can be adjusted so as to be directed toward the axis 5 </ b> S of the chuck 5.

  As described above, the axis alignment jig 19 is attached to the chuck 5 to rotationally position the rotary shaft 3, and the movable table 11 is moved in the X, Z axis direction or the X, Y, Z axis direction. Based on the position data detected by the sensor 15 to the detected portion 17 provided on the movable shaft 13 supported on the movable table 11, the shaft center 3S of the rotating shaft 3 and the shaft center 13S of the movable shaft 13 In order to detect such a slight deviation amount, the control device 9 includes a shaft rotation control unit 39, a movable shaft movement control unit 41, a measurement operation control unit 43, and a correction calculation unit 45.

  The shaft rotation control unit 39 controls the rotation of the rotating shaft 3 by controlling the control motor 7, and feeds back the detected value of the rotation detector to thereby return the origin position (reference position) of the rotating shaft 3. The rotation position from can be controlled. Note that the origin position of the rotation detector such as a rotary encoder and the origin position of the rotary shaft 3 coincide with each other.

  The movable axis movement control unit 41 controls each control motor for moving the movable table 11 in the X, Y, and Z axis directions, so that the X, Y, Z of the movable shaft 13 provided in the movable table 11 is controlled. This is for controlling the movement position in the axial direction.

  The measurement operation control unit 43 rotates the rotation shaft 3 provided with the sensor 15 and moves the movable table 11 with a slight deviation amount of the axis 13S of the movable shaft 13 with respect to the axis 3S of the rotation shaft 3. It has the function to control in order to detect.

  The correction calculation unit 45 has a function of calculating a slight deviation amount of the axis 13S of the movable shaft 13 with respect to the axis 3S of the rotary shaft 3.

  In the configuration as described above, the sensor 15 is mounted on the end face of the chuck 5, and as shown in FIG. Position the core 5S so that it is oriented. And in order to detect the deviation | shift amount of the shaft center 3S of the said rotating shaft 3, and the shaft center 13S of the movable shaft 13, it is controlled with respect to the shaft center 3S of the said rotating shaft 3 under control of the said measurement operation control part 43. The moving table 11 is moved and positioned at a predetermined position (reference position) that is set in advance facing the rotating shaft 3 so that the axis 13S of the movable shaft 13 coincides.

  Thereafter, the movable table 11 is moved in one direction in the X-axis direction so as to approach the sensor 15, and a detected portion 17 provided on the movable shaft 13 on the sensor 15 (the outer periphery of the detected portion 17 is circular). Then, the position where the axis coincides with the axis of the movable shaft 13) or the first position (X1) where the detected portion 17 is detected by the sensor 15 is measured.

  Next, the rotation shaft 3 is rotated 180 ° under the control of the measurement operation control unit 43, and the sensor 15 is rotated and positioned from the position (A) to the position (B) in FIG. Then, the movable table 11 is moved in the opposite direction (opposite direction) to the one direction, and the position where the detected portion 17 is in contact with the sensor 15 or the second position where the detected portion 17 is detected by the sensor 15. (X2) is measured.

  Next, based on the position data of the first and second positions (X1, X2), at the reference position (predetermined position) of the movable shaft 13 with respect to the rotary shaft 3 and the shaft centers 3S, 5S of the chuck 5, A slight deviation amount of the axis 13S in the X-axis direction is calculated by the correction calculation unit 45. Then, when the movable axis movement control unit 41 performs movement control of the moving table 11, the slight deviation amount in the X-axis direction is corrected by performing correction based on the calculation result of the correction calculation unit 45. It is something that can be done.

  The rotation axis 3 is rotated 90 ° to position the sensor 15 at a position rotated 180 ° from the position (C) and the position (C), and the movable table 11 is moved in the Y-axis direction to perform the same measurement. By performing the above, it is possible to detect and correct a slight deviation amount in the Y-axis direction of the axis 13S of the movable shaft 13 at the reference position with respect to the axis 3S of the rotating shaft 3.

  Therefore, when a slight deviation occurs between the axis 3S of the rotary shaft 3 and the axis 13S of the movable shaft 13 at the reference position due to the ambient temperature change, the minute deviation amount is detected and corrected. Therefore, it is possible to accurately perform high-precision processing and supply and unloading of workpieces to and from the chuck. The sensor 15 can be easily attached to and detached from the chuck 5 (rotating shaft 3), and can be easily applied to an existing machine tool. Further, the sensor 15 can be shared by a plurality of machine tools.

It is a schematic and conceptual explanatory drawing of the shaft alignment apparatus which concerns on embodiment of this invention. It is operation | movement explanatory drawing in the case of measuring the deviation | shift amount of an axial center. It is a disassembled perspective explanatory drawing of the axis alignment jig which concerns on embodiment of this invention. It is explanatory drawing of a prior art.

Explanation of symbols

1 ... Support stand (headstock)
3. Positional rotation axis (spindle)
5 ... Chuck 9 ... Control device 11 ... Moving table (tool post)
13 ... Moveable axis (tool mounting part, robot hand)
DESCRIPTION OF SYMBOLS 15 ... Sensor 17 ... Detected part 19 ... Axis alignment jig 21 ... Mounting base 23 ... Support shaft 25 ... 1st arm 33 ... 2nd arm 39 ... Shaft rotation control part 41 ... Movable axis movement control part 43 ... Measurement operation control Unit 45 ... Correction calculation unit

Claims (4)

  A centering method for aligning the axis of a movable shaft movable in a direction orthogonal to the axis of a fixed position rotating shaft that is rotatable at a fixed position with the axis of the fixed position rotating shaft, wherein the fixed position rotation After positioning the movable shaft to a predetermined position opposed to the axis of the shaft, the movable shaft is moved from the predetermined position in a predetermined direction, and the sensor is detachably attached to the fixed position rotating shaft. The first position at which the detected portion provided on the movable shaft is detected is measured, and then the fixed position rotation shaft is rotated 180 ° and the movable shaft is moved in the opposite direction of the one direction, and the movable shaft is moved by the sensor. The second position at which the detected portion provided for the measurement is detected, and the deviation amount of the predetermined position of the movable shaft with respect to the axis of the fixed-position rotating shaft based on the measured position data of the first and second positions And the fixed position is calculated based on the calculation result. Axis combined method characterized by aligning the axis of the movable shaft with respect to the axis of the rotating shaft.   2. The shaft alignment method according to claim 1, wherein the sensor is positioned between the first and second positions by rotating the fixed position rotation shaft, and a detected portion provided on the movable shaft by the sensor. A position of the third position is used to calculate the amount of deviation of the predetermined position of the movable shaft with respect to the axis of the fixed-position rotating shaft. .   A shaft rotation control unit for controlling the rotation of a fixed position rotation shaft that is rotatable at a fixed position, and a movable shaft for controlling the movement of a movable shaft that can move to a predetermined position facing the end face of the fixed position rotation shaft. A movement control unit, a sensor that can be attached to and detached from an end of the fixed-position rotating shaft, and a detected portion provided on the movable shaft by the sensor positioned at the first and second positions by the rotation of the fixed-position rotating shaft A correction calculation unit for calculating and correcting the amount of deviation of the predetermined position of the movable shaft with respect to the axis of the fixed-position rotation shaft based on the first and second measurement position data when And an axis alignment device.   A mounting base that can be attached to and detached from an end of a fixed-position rotating shaft that can rotate at a fixed position, a first arm that can rotate about the axis of a support shaft provided in the mounting base, an axis of the support shaft, and A second arm rotatable about an axis in a direction orthogonal to the longitudinal direction of the first arm, and provided on a tip side of the second arm, with respect to the axis of the fixed position rotation axis And a sensor capable of detecting a movable shaft movable in a direction orthogonal to each other.

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