JP5942741B2 - Numerical control device and rotary table position adjusting method - Google Patents

Description

  The present invention relates to a numerical controller and a rotary table position adjusting method.

  The numerical control device controls the operation of the machine tool. The machine tool includes a rotary table device. The rotary table device disclosed in Patent Document 1 includes a base, a spindle, a rotary table, and a clamp mechanism. The spindle is rotatably provided in the base. The rotary table rotates integrally with the spindle. The rotary table can reciprocate between each index position of 0 degree position and 180 position. The rotary table is provided with pallets P1 and P2 across the center of rotation. The pallets P1 and 2 hold the workpieces on the upper surfaces, respectively. When the rotary table is indexed to the 0 degree position, the pallet P1 is located in the machining area of the machine tool. When the rotary table is indexed to the 180 degree position, the pallet P2 is located in the machining area of the machine tool.

  The rotary table device includes an indexing mechanism. The indexing mechanism of the stopper system includes a first stopper piece, a second stopper piece, a first positioning member, and a second positioning member. The first stopper piece and the second stopper piece are respectively provided on the outer surface of the base, and are fixed to the same radial position with a bolt or the like at a predetermined angle (for example, 90 degrees) across the rotation center of the rotary table. On the other hand, the first positioning member and the second positioning member are provided on the lower surface side of the rotary table. The numerical control device rotates the rotary table counterclockwise in order to determine the rotary table at the 0 degree position. The first positioning member contacts the first stopper piece. The rotary table is indexed at the 0 degree position, and the pallet P1 is located in the machining area. The numerical controller rotates the rotary table clockwise in order to determine the rotary table at the 180 degree position. The second positioning member contacts the second stopper piece. The rotary table is indexed at a 180 degree position, and the pallet P2 is located in the machining area.

  Based on the positioning command in the NC program, the numerical controller rotates the rotary table and positions it at the 0 degree position or the 180 degree position. The clamp mechanism clamps the rotary table positioned at the 0 degree position or the 180 degree position. The numerical manufacturing apparatus starts machining the workpiece held on the pallet P1 or 2 located in the machining area.

JP 2004-142081 A

  The position of the rotary table commanded by the positioning command is the target position, and the actual movement position of the rotary table is the actual position. When the rotary table is indexed, a deviation amount is generated at each index position. The deviation amount is a difference between the target position and the actual position. The deviation amount may be biased between when the rotary table is indexed at the 0 degree position and when it is indexed at the 180 degree position. If the deviation amount is biased, even if the pallet on one side is indexed and rotated 180 degrees, there may be a situation where it cannot be stopped by the drive motor for rotating the rotary table, the backlash of the speed reducer, or the like. Therefore, it is necessary to rotate the rotary table clockwise and counterclockwise, and to calculate the amount of deviation and to adjust both of them evenly in a state where the positioning members are respectively applied to the stopper pieces. The operator needs to perform calculation for adjustment and input the calculation result on the screen, and the operation is complicated.

  An object of the present invention is to provide a numerical control device and a rotary table position adjusting method capable of equalizing deviation amounts at a 0 degree position and a 180 degree position of the rotary table.

  A numerical control device according to claim 1 of the present invention comprises: a rotary table that supports a base portion so that it can rotate between 0 degrees and 180 degrees around one axis so as to be able to rotate forward and reverse, and holds the workpiece; A motor to be driven, a pair of stoppers provided on the base, and a first indexing position corresponding to 0 degrees, provided on the rotary table and corresponding to each stopper, and corresponding to 180 degrees A numerical control device for controlling a rotary table device having a pair of positioning portions for positioning the rotary table at a second index position, wherein the motor is driven to rotate the rotary table in one direction. Then, one of the pair of positioning portions is brought into contact with one of the pair of stopper portions, the rotary table is positioned at the first index position, and the position of the rotary table is provisionally determined as a reference position. With provisional decision means After the temporary determining means positions the position of the rotary table at the first index position, the motor is driven to rotate the rotary table in the direction opposite to the one direction, and the other is different from the one. A first positioning means for abutting the positioning portion on the other stopper portion different from the one and positioning the rotary table at the second indexing position; and First position storage means for storing the first position of the motor when positioned at the two index positions, driving the motor, rotating the rotary table in the one direction, and moving the one positioning portion to the one position A second positioning means for contacting the one stopper portion to position the rotary table at the first index position; and the second positioning means for positioning the rotary table at the first index position. Between the second position storage means for storing the second position of the motor at the time, the first position stored by the first position storage means and the second position stored by the second position storage means. A difference amount calculation means for calculating a difference amount between the actually measured amount and a reference amount corresponding to 180 degrees, and the reference position is shifted and changed by an equal amount obtained by dividing the difference amount calculated by the difference amount calculation means. And a changing means. The rotary table can rotate forward and reverse between 0 degree and 180 degrees, and can be positioned at the first index position and the second index position. Since the numerical control device has the above-described configuration, each deviation amount when positioned at the first index position and the second index position can be made equal.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, based on a first control command that instructs positioning to a first target position corresponding to the first index position, When the motor is driven, the rotary table is rotated in the one direction, the one positioning portion is brought into contact with the one stopper portion, and the rotary table is positioned at the first index position. First deviation amount calculating means for calculating a first deviation amount that is a difference between the actual position of the rotary table and the first target position, and positioning to a second target position corresponding to the second index position. Based on the instructed second control command, the motor is driven to rotate the rotary table in the opposite direction, the other positioning portion is brought into contact with the other stopper portion, and the rotary table is moved to the first table. Positioned at the two index positions A second deviation amount calculating means for calculating a second deviation amount that is a difference between the actual position of the rotary table and the second target position, and the first deviation calculated by the first deviation amount calculating means. Difference determining means for determining whether or not a difference amount between the amount and the second deviation amount calculated by the second deviation amount calculating means is equal to or greater than a predetermined value, and equality obtained by dividing the difference amount determined by the difference determining means into two A reference position changing unit that shifts and changes the reference position by an amount, and when the difference determining unit determines that the difference amount is equal to or greater than the predetermined value, the reference position changing unit shifts the reference position. And a re-execution unit that re-executes the processes of the first deviation amount calculation unit, the second deviation amount calculation unit, and the difference determination unit. If the difference between the first deviation amount and the second deviation amount is greater than or equal to a predetermined value, there is a possibility that a problem has occurred in any of the processes of the first deviation amount calculation means and the second deviation amount calculation means. . In that case, the re-execution unit executes the processing of each unit again. Therefore, the numerical control device can make the deviation amount uniform.

  According to a third aspect of the present invention, in addition to the configuration of the second aspect of the invention, the numerical control device counts the number of times the re-execution means executes the processing, and the count value of the counting means is The number-of-times determining means for determining whether or not the number of times is equal to or greater than the predetermined number of times, and a notifying means for notifying abnormality when the number of times determining means determines that the count value is equal to or greater than the predetermined number of times. If the deviation amount is equal to or greater than a predetermined value even after the re-execution means executes the process of each means a predetermined number of times or more, the rotary table device may have some trouble. In that case, since the notification means notifies the abnormality, the operator can promptly respond to the apparatus abnormality.

  According to a fourth aspect of the invention, in addition to the configuration of the first aspect of the invention, the first target position is shifted in the one direction from the first index position. The second target position is a position shifted in the opposite direction from the second index position. Therefore, the rotary table device can reliably contact one positioning portion with one stopper portion and the other positioning portion with the other stopper portion.

  According to a fifth aspect of the present invention, there is provided a rotary table position adjusting method comprising: a rotary table that supports a base portion so that it can rotate between 0 degrees and 180 degrees around one axis so as to be able to rotate forward and reverse; Motor, a pair of stoppers provided on the base part, provided on the rotary table, abutting each stopper part, corresponding to a first index position corresponding to 0 degrees, and corresponding to 180 degrees A rotary table position adjustment method performed by a numerical controller that controls a rotary table device that includes a pair of positioning units that position the rotary table at a second indexing position, wherein the motor is driven, The rotary table is rotated in one direction, one of the pair of positioning portions is brought into contact with one of the pair of stopper portions, and the rotary table is positioned at the first indexing position. Place Tentatively determining as a reference position, and after positioning the rotary table at the first index position in the temporary determining step, the motor is driven to move the rotary table in the one direction. A first positioning step of rotating the rotating table in the second indexing position by rotating in the opposite direction to the other, contacting the other positioning portion different from the one with the other stopper portion different from the one A first position storing step for storing a first position of the motor when the rotary table is positioned at the second index position in the first positioning step; A second positioning step in which the one positioning portion is brought into contact with the one stopper portion to position the rotary table at the first index position, and the second positioning The second position storing step of storing the second position of the motor when the rotary table is positioned at the first indexing position, the first position stored in the first position storing step, and the A difference amount calculation step for calculating a difference amount between the actually measured amount stored in the second position storage step and the reference amount corresponding to 180 degrees, and the difference amount calculation step. And a change step of changing the reference position by shifting the difference amount by an equal amount. The numerical control device can obtain the effect of the first aspect by performing the rotary table position adjusting method.

The perspective view of the machine tool 50. FIG. The top view of the rotary table apparatus 1. FIG. FIG. 3 is a cross-sectional view taken along the line II in FIG. 2. The bottom view of the turntable 10. FIG. The perspective view around the clamp mechanism 19. The top view around the clamp mechanism 19. FIG. 2 is a block diagram showing an electrical configuration of a numerical control device 70 and a machine tool 50. The flowchart of a reference position adjustment process. The flowchart of a reference position adjustment process. The flowchart of a deviation amount confirmation process.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The structure of the machine tool 50 will be described with reference to FIG. The machine tool 50 includes a base portion 52, a machine body 53, a protective cover 55, a control box 56, and the turntable device 1. The base unit 52 is a base of the machine tool 50. The machine body 53 is provided behind the upper surface of the base portion 52. The machine body 53 cuts a workpiece (not shown). The protective cover 55 is provided on the upper portion of the base portion 52. The protective cover 55 surrounds the machine main body 53. The protective cover 55 prevents the chips and the cutting fluid from splashing from the machine body 53 to the outside. The control box 56 is provided on the back surface of the protective cover 55. The control box 56 stores a numerical controller 70 (see FIG. 7). The numerical controller 70 controls the operation of the machine tool 50 based on the NC program stored in the nonvolatile storage device 74. The turntable device 1 is provided in front of the upper surface of the base portion 52.

  The structure of the machine body 53 will be described. The machine body 53 includes a main base 63, a column 58, a main spindle head 59, a main spindle 60, and an automatic tool changer 65. The main stand 63 is provided behind the upper surface of the base portion 52. The column 58 is provided so as to be movable on the main base 63 in the X-axis direction and the Y-axis direction. The spindle head 59 can move in the Z-axis direction along the front surface of the column 58. The main shaft 60 is provided below the main shaft head 59. The spindle 60 is equipped with a tool (not shown) and rotates at a high speed by driving the spindle motor 92. The machine tool 50 cuts the workpiece by relative movement between the tool mounted on the spindle 60 and the workpiece held on the rotary table 10 of the rotary table device 1. The automatic tool changer 65 is provided in the vicinity of the spindle head 59. The automatic tool changer 65 exchanges the tool mounted on the spindle 60 with another tool based on the NC program tool change command.

  As shown in FIG. 2, the turntable device 1 has a turntable 10 at the top. The turntable 10 is formed in a rectangular shape in plan view and can reciprocate between a first index position and a second index position. The first index position is the 0 degree position, and the second index position is the -180 degree position (see FIG. 8). The turntable 10 includes a pallet P1 on one end side in the longitudinal direction and a pallet P2 on the other end side with the rotation center therebetween. The pallets P1 and P2 can hold a workpiece using a jig or the like. When the numerical controller 70 positions the rotary table 10 at the first index position, the pallet P <b> 1 is disposed in the machining area of the machine tool 50. When the rotary table 10 is positioned at the second index position, the pallet P <b> 2 is disposed in the machining area of the machine tool 50. When the rotary table 10 is positioned at the first index position, while the work held on the pallet P1 is being processed by the machine tool 50, the operator can remove the processed work held on the pallet P2 and attach an unprocessed work. .

  The structure of the rotary table device 1 will be described with reference to FIGS. As shown in FIGS. 2 and 3, the turntable device 1 includes a base 2, a turntable 10, and a clamp mechanism 19 (see FIG. 5).

  As shown in FIG. 3, the base 2 is a rectangular parallelepiped metal base. The base 2 includes a bearing 4, an outer bearing retainer 15, an inner bearing retainer 16, seal members 17 and 18, a cavity 2A, a large gear 5, and a table motor 96 (see FIG. 2). The bearing 4 has a substantially ring shape in plan view. The bearing 4 is disposed so as to surround the outer periphery of the spindle 3. The outer peripheral surface of the spindle 3 slides along the rolling surface of the bearing 4. Therefore, the bearing 4 can rotatably support the spindle 3.

  Both the outer bearing retainer 15 and the inner bearing retainer 16 have a ring shape in plan view. The outer bearing retainer 15 has a larger diameter than the inner bearing retainer 16. The inner bearing retainer 16 is located inside the outer bearing retainer 15. The outer bearing retainer 15 and the inner bearing retainer 16 press the bearing 4 from above to the base 2 side. The inner bearing retainer 16 is fixed to the spindle 3 with a plurality of screws (not shown). The outer bearing retainer 15 is fixed to the base 2 with a plurality of screws (not shown). The seal members 17 and 18 are inserted between the circumferential lower surface groove of the rotary table 10 and the circumferential upper surface groove of the base 2 on the upper and lower surfaces of the outer bearing retainer 15.

  As shown in FIG. 3, the cavity 2A is provided in the center inside the base 2 and the upper part is opened. The large gear 5 is provided in the cavity 2A. The large gear 5 has an axis line in the vertical direction, is fitted to the lower part of the spindle 3, and is fixed to the spindle 3 with a plurality of bolts (not shown). The bolt is inserted from the upper surface of the rotary table 10. Therefore, the large gear 5 rotates integrally with the spindle 3 and the rotary table 10.

  As shown in FIG. 2, the table motor 96 is disposed outside the base 2. The table motor 96 is a servo motor and rotationally drives the drive shaft 8 via a speed reducer 97. As shown in FIGS. 2 and 3, the drive shaft 8 penetrates the base 2 horizontally and has a tip portion located in the cavity 2 </ b> A. The drive shaft 8 is provided with a gear 9 at the tip. The gear 9 meshes with a tooth portion (not shown) formed in the lower portion of the large gear 5. Therefore, when the table motor 96 is driven, the rotary table 10 rotates via the drive shaft 8, the large gear 5 and the spindle 3.

  The turntable 10 is provided on the base 2. As shown in FIG. 2, the rotary table 10 has grooves 12 and 13 formed on both the left and right sides of the upper surface (upper and lower sides in FIG. 2). The grooves 12 and 13 are used to fix the workpiece directly or indirectly through a jig. As shown in FIG. 3, the rotary table 10 has a lower cover body 14 attached to the lower surface. The lower cover body 14 covers the outer side of the base 2 on the lower surface of the rotary table 10.

  The positioning mechanism of the rotary table 10 will be described with reference to FIGS. The rotary table device 1 can position the rotary table 10 at the first index position and the second index position, respectively. As shown in FIG. 2, the base 2 includes a first stopper piece 21A and a second stopper piece 21B on the outer surface. The first stopper piece 21A and the second stopper piece 21B have a substantially rectangular shape in plan view, and are fixed to the same radial position with a bolt or the like at a predetermined angle θ1 (for example, θ1 = 90 degrees) across the rotation center of the rotary table 10. .

  On the other hand, as shown in FIGS. 2 and 4, the turntable 10 includes a first positioning member 22A and a second positioning member 22B on the lower surface side. The first positioning member 22A comes into contact with the first stopper piece 21A (see FIGS. 5 and 6) when the rotary table 10 rotates counterclockwise (in the direction of the arrow (+) in FIG. 2). The rotary table 10 is positioned at the extended position. The second positioning member 22B contacts the second stopper piece 21B to position the rotary table 10 at the second index position when the rotary table 10 rotates clockwise (in the direction of the arrow (−) in FIG. 2). . In the present embodiment, the rotary table 10 is rotated 180 degrees clockwise and counterclockwise.

  The clamp mechanism 19 will be described with reference to FIGS. The clamp mechanism 19 is a mechanism that clamps the rotary table 10 and fixes (locks) the rotary table 10 at index positions of 0 degree position and 180 degree position. The clamp mechanism 19 includes a first clamp block 33A, a second clamp block 33B, a support block 36, a support shaft 37, a clamp arm 38, a bracket 40, a cam follower 34, an air cylinder 35, and the like.

  As shown in FIG. 4, the first clamp block 33 </ b> A and the second clamp block 33 </ b> B are respectively fixed at positions facing each other in the diametrical direction across the rotation center of the spindle 3 (see FIG. 3) on the lower surface of the rotary table 10. .

  As shown in FIG. 5, the support block 36 is provided on the outer surface of the base 2. The support shaft 37 is provided on the support block 36. The plate-like clamp arm 38 is rotatably supported on the support shaft 37. The clamp arm 38 pivotally supports the cam follower 34 at the tip so as to be horizontally rotatable. The bracket 40 protrudes from the outer surface of the base 2. The air cylinder 35 is a cylindrical machine that converts the energy of compressed air into linear motion. The base end of the air cylinder 35 is attached to the bracket 40 via a pin 41 (see FIG. 6) so as to be horizontally rotatable. The air cylinder 35 includes a piston rod 35A that moves forward and backward. The tip of the piston rod 35A is rotatably connected to the clamp arm 38 and a pin 42 (see FIG. 5).

  The operation of the clamp mechanism 19 will be described with reference to FIGS. First, the piston rod 35A of the air cylinder 35 is retracted. The clamp arm 38 moves backward in the direction of arrow D in FIG. The cam follower 34 comes close to the outer surface of the base 2. Hereinafter, the case where the turntable 10 rotates in the plus direction (arrow (+) direction) and the case where the turntable 10 rotates in the minus direction (arrow (−) direction) will be described in order. The positive direction is counterclockwise and the negative direction is clockwise.

  The case where it rotates in the plus direction will be described. In FIG. 2, the rotary table 10 rotates in the plus direction (the arrow (+) direction in FIGS. 2 and 6). The first positioning member 22A comes into contact with the first stopper piece 21A from the upstream side in the rotational direction (the state shown in FIGS. 2, 5, and 6). As shown in FIG. 6, the first clamp block 33A moves on the side away from the outer surface of the base 2 on the side surface of the cam follower 34 from the upstream side in the rotational direction toward the downstream direction (arrow (+) direction). It stops at a position close to the side surface on the downstream side of the rotation.

  In the above state, the piston rod 35A of the air cylinder 35 is advanced. The clamp arm 38 rotates counterclockwise (arrow C direction) in FIGS. 5 and 6 and presses the inclined contact surface of the first clamp block 33A. The air cylinder 35 is in an operating state. Therefore, the cam follower 34 bites into the contact surface of the first clamp block 33A so that the pressing force increases. The rotary table 10 tries to rotate clockwise. Since the first positioning member 22A is in contact with the first stopper piece 21A, the contact force is increased. By both actions, the turntable 10 is firmly fixed at the first index position of 0 degrees, and the pallet P1 is indexed.

  The case where it rotates in the minus direction will be described. In FIG. 2, the rotary table 10 rotates in the minus direction (the direction of the arrow (−) in FIGS. 2 and 6). The second positioning member 22B comes into contact with the second stopper piece 21B from the upstream side of the rotation. The piston rod 35A of the air cylinder 35 is moved backward. The clamp arm 38 moves backward in the direction of arrow D in FIG. The cam follower 34 comes close to the outer surface of the base 2. As shown in FIG. 6, the second clamp block 33 </ b> B moves on the side away from the outer surface of the base 2 among the side surfaces of the cam follower 34 from the upstream side in the rotational direction toward the downstream direction (arrow (−) direction). It stops at a position close to the side surface on the downstream side of the rotation.

  In the above state, the piston rod 35A of the air cylinder 35 is advanced. The clamp arm 38 rotates counterclockwise (arrow C direction) in FIG. 6 and presses the inclined contact surface of the second clamp block 33B. The air cylinder 35 is in an operating state. Therefore, the cam follower 34 bites into the contact surface of the second clamp block 33B so that the pressing force increases. The rotary table 10 tries to rotate counterclockwise. Since the second positioning member 22B is in contact with the second stopper piece 21B, the contact force is increased. By both actions, the rotary table 10 is firmly fixed at the second index position of −180 degrees, and the pallet P2 is indexed.

  With reference to FIG. 7, the electrical configuration of the numerical controller 70 will be described. The numerical control device 70 includes a CPU 71, a ROM 72, a RAM 73, a nonvolatile storage device 74, an input / output unit 75, drive circuits 81 to 86, and the like. The CPU 71 performs overall control of the numerical control device 70. The ROM 72 stores a reference position adjustment program, a deviation amount confirmation program, and the like in addition to the main program. The reference position adjustment program is a program for executing a reference position adjustment process (see FIG. 9) described later. The deviation amount confirmation program is a program for executing deviation amount confirmation processing (see FIG. 10).

  The RAM 73 temporarily stores various data during execution of various processes. The non-volatile storage device 74 stores a plurality of NC programs and the like that are registered by the operator using the input device 77. The NC program is composed of a plurality of blocks including various control commands, and controls various operations including axis movement of the machine tool 50, tool change, and the like in units of blocks.

  The drive circuit 81 is connected to the Z-axis motor 91 and the encoder 101. The drive circuit 82 is connected to the spindle motor 92 and the encoder 102. The drive circuit 83 is connected to the X-axis motor 93 and the encoder 103. The drive circuit 84 is connected to the Y-axis motor 94 and the encoder 104. The drive circuit 85 is connected to the magazine motor 95 and the encoder 105. The drive circuit 86 is connected to the table motor 96 and the encoder 106.

  The drive circuits 81 to 86 receive commands from the CPU 71 and output drive currents to the corresponding motors 91 to 96, respectively. The drive circuits 91 to 96 receive feedback signals from the encoders 101 to 106 and perform feedback control of position and speed. The feedback signal is a pulse signal. The input / output unit 75 is connected to an input device 77 and a display device 78, respectively.

  The user can select one NC program from among a plurality of NC programs with the input device 77. The CPU 71 displays the selected NC program on the display device 78. The CPU 71 controls the operation of the machine tool 50 based on the NC program displayed on the display device 78.

  With reference to FIG. 8, the target position in each index position is demonstrated. In order to position the rotary table 10 at the first index position, the CPU 71 outputs a first position control command to the drive circuit 86. The first position control command is a command for positioning the rotary table 10 at the first target position. The first target position is, for example, a position shifted by 1 ° in the plus direction from the 0 ° position. The first target position may be a position shifted by 1 ° or more as long as it is in the plus direction from the 0 ° position. On the other hand, in order to position the rotary table 10 at the second index position, the CPU 71 outputs a second position control command to the drive circuit 86. The second position control command is a command for positioning the rotary table 10 at the second target position. The second target position is, for example, a position shifted by −1 ° in the minus direction from the −180 ° position. The second target position may be a position shifted by −1 ° or more as long as it is in the minus direction from the −180 position. The amount of deviation between the first target position and the second target position is preferably the same.

  When the turntable 10 rotates in the plus direction (the (+) direction in FIG. 8), the first positioning member 22A comes into contact with the first stopper piece 21A at the first index position. The rotary table 10 tries to rotate to the 1 ° position which is the first target position. Therefore, the first positioning member 22A can reliably contact the first stopper piece 21A. Based on the first position control command, the table motor 96 tries to rotate the rotary table 10 to the first target position in a state where the first positioning member 22A is in contact with the first stopper piece 21A. The current command value of the table motor 96 increases. The numerical controller 70 can recognize that the rotary table 10 has been positioned at the first index position by detecting an increase in the current command value of the table motor 96.

  When the turntable 10 rotates in the minus direction (the (−) direction in FIG. 8), the second positioning member 22B comes into contact with the second stopper piece 21B at the second index position. The rotary table 10 tries to rotate to a position of -181 ° which is the second target position. Therefore, the second positioning member 22B can reliably contact the second stopper piece 21B. Based on the second position control command, the table motor 96 attempts to rotate the rotary table 10 to the second target position with the second positioning member 22B in contact with the second stopper piece 21B. The current command value of the table motor 96 increases. The numerical controller 70 can recognize that the rotary table 10 has been positioned at the second index position by detecting an increase in the current command value of the table motor 96.

  The deviation amount at each index position will be described with reference to FIG. A range between the first index position and the second index position is a movable range of the rotary table 10. The difference between the first index position and the first target position is the first deviation amount. The difference between the second index position and the second target position is the second deviation amount. The first deviation amount and the second deviation amount may be biased due to backlash between the table motor 96 and the speed reducer 97. In the present embodiment, the CPU 71 executes a reference position adjustment process (see FIG. 9) and a deviation amount confirmation process (see FIG. 10), which will be described later, in order to equalize the first deviation amount and the second deviation amount.

  The reference position adjustment process will be described with reference to FIGS. The reference position adjustment process is a process for uniformly adjusting the first deviation amount and the second deviation amount of the rotary table 10. When the numerical controller 70 is activated, the operator operates the input device 77 to select the reference position adjustment function of the rotary table device 1. The CPU 71 calls a reference position adjustment program from the ROM 72 and executes this processing. A symbol T shown in FIG. 8 indicates the position of the rotary table 10.

  As shown in the first step of FIG. 8, the CPU 71 outputs a first position control command and rotates the turntable 10 in the plus direction (S1). The rotary table 10 tries to rotate to the first target position. The first positioning member 22A contacts the first stopper piece 21A. The current command value of the table motor 96 increases. The CPU 71 determines whether or not the current command value is greater than or equal to the reference value (S2). The reference value is stored in the nonvolatile storage device 74. When the CPU 71 determines that the current command value is less than the reference value (S2: NO), the first positioning member 22A is not in contact with the first stopper piece 21A, and the rotary table 10 reaches the first index position. Not. The CPU 71 returns to S2 and repeats the process until the current command value becomes equal to or greater than the reference value.

  When the CPU 71 determines that the current command value is equal to or greater than the reference value (S2: YES), the first positioning member 22A is surely in contact with the first stopper piece 21A, and the rotary table 10 has reached the first index position. The CPU 71 provisionally determines the current actual position of the turntable 10 as a reference position (S3). The reference position is a 0 ° position.

  Next, as shown in the second step of FIG. 8, the CPU 71 outputs a second position control command and rotates the turntable 10 in the minus direction (S4). The rotary table 10 tries to rotate to the second target position. The second positioning member 22B contacts the second stopper piece 21B. The current command value of the table motor 96 increases. The CPU 71 determines whether or not the current command value is greater than or equal to the reference value (S5). When the CPU 71 determines that the current command value is less than the reference value (S5: NO), the second positioning member 22B is not in contact with the second stopper piece 21B. The rotary table 10 has not reached the second index position. The CPU 71 returns to S5 and repeats the process until the current command value becomes equal to or greater than the reference value.

  When the CPU 71 determines that the current command value is equal to or greater than the reference value (S5: YES), the second positioning member 22B is in contact with the second stopper piece 21B with certainty. The rotary table 10 has reached the second index position. The CPU 71 stores the first pulse value output from the encoder 106 in the RAM 73 (S6). The first pulse value corresponds to the position of the table motor 96 at the actual position of the turntable 10 that has reached the second index position. In the present embodiment, it is assumed that 1 ° corresponds to 10 pulses and the first pulse value is 1810 pulses.

  Next, as shown in the third step of FIG. 8, the CPU 71 outputs the first position control command again and rotates the turntable 10 in the plus direction (S7). The rotary table 10 tries to rotate to the first target position. The first positioning member 22A contacts the first stopper piece 21A. The current command value of the table motor 96 increases. The CPU 71 determines whether or not the current command value is greater than or equal to the reference value (S8). When the CPU 71 determines that the current command value is less than the reference value (S8: NO), the first positioning member 22A is not in contact with the first stopper piece 21A. The rotary table 10 has not reached the first index position. The CPU 71 returns to S8 and repeats the process until the current command value becomes equal to or greater than the reference value.

  When the CPU 71 determines that the current command value is equal to or greater than the reference value (S8: YES), the first positioning member 22A is in contact with the first stopper piece 21A with certainty. The rotary table 10 has reached the first index position. The CPU 71 stores the second pulse value output from the encoder 106 in the RAM 73 (S9). The second pulse value corresponds to the position of the table motor 96 at the actual position of the turntable 10 that has reached the second index position. This embodiment assumes a case where the second pulse value is 0 pulse.

  The CPU 71 calculates an actual measurement amount (S10). The actually measured amount is the difference between the first pulse value and the second pulse value stored in the RAM 73, and the angle amount that the rotary table 10 is actually rotated from the second index position to the first index position is the pulse value of the encoder 106. It is a converted value. Originally, since the angle amount by which the rotary table 10 rotates from the second index position to the first index position is 180 °, 1800 pulses is the reference amount. The CPU 71 calculates a difference amount between the actually measured amount and the reference amount (S11). In the present embodiment, the actually measured amount is 1810-0 = 1810 pulses and the reference amount = 1800 pulses, so the difference amount is 10 pulses. In order to equalize the first deviation amount and the second deviation amount, it is necessary to adjust the rotation control range of the turntable 10 to the center with respect to the movable range of the turntable 10. The rotation control range is a range for controlling the rotation of the turntable 10. The rotation control range of the turntable 10 is shifted in the plus direction by an angle corresponding to the difference amount.

  Next, as shown in the fourth step of FIG. 8, the CPU 71 changes the reference position temporarily determined in S3 by shifting it in the minus direction by an equal amount obtained by dividing the difference amount by two (S12). In the present embodiment, since the difference amount is 10 pulses, the difference amount is changed by shifting in the negative direction by 0.5 °, which is an angle amount of 5 pulses obtained by equally dividing 10 pulses into two. Therefore, the rotation control range of the turntable 10 is located at the center of the movable range. The rotary table device 1 can adjust the first deviation amount and the second deviation amount evenly. The CPU 71 outputs an alarm (S13), notifies that the adjustment of the index position of the turntable 10 has been completed, and ends this process.

  The deviation amount confirmation process will be described with reference to FIG. The deviation amount confirmation process is a process for confirming that the first deviation amount and the second deviation amount are equal. The operator operates the input device 77 to select the index position adjustment function of the rotary table device 1. The CPU 71 calls a deviation amount confirmation program from the ROM 72 and executes this processing. The operator may select this function after executing the reference position adjustment process.

  The CPU 71 initializes the retry counter R (S20). The retry counter R counts the number of executions of a reference position changing process (S33) described later. The count value of the retry counter R is stored in the RAM 73. The CPU 71 determines whether or not the turntable 10 is in an unindexed state (S21). The CPU 71 detects the current position of the turntable 10 with the encoder 106, and determines whether or not it is at the first index position or the second index position. When the rotary table 10 is in the unindexed state (S21: YES), the CPU 71 calculates the pallet P1 or P2 that is closer to the machining area of the machine tool 50 (S22). When indexing the pallet P1, the rotary table 10 is rotated in the plus direction and positioned at the first index position. When indexing the pallet P2, the rotary table 10 is rotated in the minus direction and positioned at the second index position. If the turntable 10 has already been indexed to the first index position or the second index position (S21: NO), the CPU 71 advances the process to S23.

  For example, when the turntable 10 is indexed to the second index position, the CPU 71 rotates the turntable 10 in the plus direction, which is the reverse direction, and positions it at the first index position (S23). The CPU 71 calculates the deviation amount H1 and stores it in the RAM 73 (S24). The CPU 71 detects the current actual position of the table motor 96 with the encoder 106, and calculates a deviation amount H1 that is a difference from the first target position.

  Next, the CPU 71 rotates the turntable 10 in the negative direction, which is the reverse direction, and positions it at the second index position (S25). The CPU 71 calculates the deviation amount H2 (S26), and calculates the difference between the deviation amounts H1 and H2 (S27).

  The CPU 71 determines whether or not the calculated difference is less than the reference value (S28). The reference value is a reference for determining whether or not the deviation amounts H1 and H2 are equal, and is stored in the nonvolatile storage device 74. When the calculated difference is less than the reference value (S28: YES), the CPU 71 displays the adjustment completion message on the display device 78 because the index position adjustment of the rotary table 10 has been normally completed (S29). The process ends.

  When the calculated difference is greater than or equal to the reference value (S28: NO), the CPU 71 determines whether or not the count value of the retry counter R is greater than or equal to a predetermined value (S31). The predetermined value is the number of times that a reference position changing process in S33 described later is permitted, and is stored in the nonvolatile storage device 74. In the present embodiment, the predetermined value is set to 2. When it is determined that the count value of the retry counter R is less than the predetermined value (S31: NO), the reference position is shifted by an equal amount obtained by dividing the difference amount, which is the deviation amount H2−the deviation amount H1, into two, and the reference position is changed (S33). ). The CPU 71 adds 1 to the retry counter R (S34), returns to S23, calculates again the deviation amounts H1 and H2, and determines whether or not the difference is less than the reference value (S23 to S28).

  When it is determined that the count value of the retry counter R is equal to or greater than the predetermined value (S31: YES), the deviation amounts H1 and H2 are not equal even if the reference position changing process is executed many times. The rotary table device 1 may have other problems. The CPU 71 displays an adjustment error message on the display device 78 (S32), and ends this process. The operator can quickly cope with the malfunction of the rotary table device 1 by checking the adjustment error message.

  In the above description, the CPU 71 that executes the processes of S1 to S3 in FIG. 9 corresponds to the provisional determination means of the present invention. The CPU 71 that executes the processes of S4 and S5 corresponds to the first positioning means of the present invention. The CPU 71 that executes the process of S6 corresponds to the first position storage means of the present invention. The CPU 71 that executes the processes of S7 to S8 corresponds to the second positioning means of the present invention. The CPU 71 that executes the process of S9 corresponds to the second position storage means of the present invention. The CPU 71 that executes the processes of S10 and S11 corresponds to the difference amount calculation means of the present invention. The CPU 71 that executes the process of S12 corresponds to the changing means of the present invention. The CPU 71 that executes the process of S33 shown in FIG. 10 corresponds to the reference position changing means of the present invention. The CPU 71 that executes the processes of S33 and S23 to S28 corresponds to the re-execution means of the present invention.

  As described above, the numerical control device 70 of the present embodiment controls the rotary table device 1. The turntable device 1 includes a turntable 10, a table motor 96, a pair of stopper pieces 21A and 21B, and a pair of positioning members 22A and 22B. The turntable 10 supports the base 2 so that it can rotate between 0 degrees and 180 degrees around one axis so as to be able to rotate forward and reverse. The table motor 96 drives the rotary table 10. A pair of stopper pieces 21 </ b> A and 21 </ b> B are provided on the base 2. A pair of positioning members 22A and 22B are provided on the turntable 10, and come into contact with the stopper pieces 21A and 21B, respectively, in a first index position corresponding to 0 degrees and a second index position corresponding to 180 degrees. The rotary table 10 is positioned.

  The CPU 71 of the numerical control device 70 executes a reference position adjustment process. The CPU 71 drives the table motor 96 to rotate the rotary table 10 in the plus direction. The first positioning member 22A contacts the first stopper piece 21A. The CPU 71 positions the turntable 10 at the first index position, and temporarily determines the position of the turntable 10 as a reference position. The CPU 71 drives the table motor 96 to rotate the rotary table 10 in the minus direction. The second positioning member 22B contacts the second stopper piece 21B. The CPU 71 positions the rotary table 10 at the second index position and stores the first pulse value of the encoder 106. The CPU 71 drives the table motor 96 to position the rotary table 10 again at the first index position. The CPU 71 stores the second pulse value output from the encoder 106. The CPU 71 calculates a difference amount between the actually measured amount and the reference amount. The actually measured amount is the difference between the first pulse value and the second pulse value. The reference amount is a pulse value corresponding to 180 degrees. The CPU 71 shifts and changes the reference position by an equal amount obtained by dividing the calculated difference amount into two. The rotation control range of the turntable 10 is located at the center of the movable range. Therefore, the rotary table device 1 can evenly adjust the first deviation amount and the second deviation amount when positioned at the first index position and the second index position.

  In the present embodiment, the CPU 71 further outputs a first control command to the drive circuit 86. The first control command is a command for instructing positioning to the first target position. The first target position corresponds to the first index position. The CPU 71 calculates a first deviation amount when the rotary table 10 is positioned at the first index position. The first deviation amount is a difference between the actual position of the rotary table 10 and the first target position. The CPU 71 outputs a second control command to the drive circuit 86. The second control command is a command for instructing positioning to the second target position. The second target position corresponds to the second index position. The CPU 71 calculates a second deviation amount when the rotary table 10 is positioned at the second index position. The second deviation amount is a difference between the actual position of the rotary table 10 and the second target position. The CPU 71 determines whether the difference amount between the first deviation amount and the second deviation amount is equal to or greater than a predetermined value. When the difference amount is equal to or larger than a predetermined value, the CPU 71 shifts the reference position by an equal amount obtained by dividing the difference amount into two, recalculates the first deviation amount and the second deviation amount, and determines whether the difference amount is equal to or larger than the predetermined amount. . The CPU 71 repeats these processes until the difference amount becomes less than a predetermined value. Therefore, the numerical controller 70 can adjust the first deviation amount and the second deviation amount evenly.

  Further, in the present embodiment, when it is determined that the number of times of executing the reference position changing process (S33) is equal to or greater than the predetermined number, the rotary table device 1 may have some problem. In that case, since CPU71 alert | reports abnormality, an operator can respond to abnormality of the rotary table apparatus 1 rapidly.

  In the present embodiment, the first target position is a position shifted in the plus direction from the first index position, and the second target position is a position shifted in the minus direction from the second index position. Therefore, the numerical controller can reliably contact the first positioning member 22A with the first stopper piece 21A and the second positioning member 22B with the second stopper piece 21B.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation is possible. For example, in the above-described embodiment, in the reference position adjustment process shown in FIG. 9, the rotary table 10 is first rotated in the plus direction and positioned at the first index position to temporarily determine the reference position (S1 to S1). 3) The reference position may be provisionally determined by rotating in the minus direction and positioning at the second index position. In that case, the CPU 71 may store the first pulse value and the second pulse value in the order of the first index position and the second index position.

  Further, in the present embodiment, in the deviation amount confirmation process shown in FIG. 10, a retry counter R is provided, and an adjustment error message is displayed when the number of executions of the reference position change process in S33 exceeds a predetermined value. However, without providing the retry counter R, an adjustment error message may be displayed when the difference in the deviation amount is greater than or equal to the reference value.

  In the present embodiment, the first index position is described as 0 degree position and the second index position is defined as -180 degree position. However, the plus direction and the minus direction may be reversed. The position is 180 degrees.

DESCRIPTION OF SYMBOLS 1 Rotary table apparatus 2 Base 10 Rotary table 21A 1st stopper piece 21B 2nd stopper piece 22A 1st positioning member 22B 2nd positioning member 50 Machine tool 70 Numerical control apparatus 71 CPU
72 ROM
73 RAM
74 Nonvolatile storage device 78 Display device 96 Table motor 106 Encoder

Claims (5)

A rotating table that supports the base portion so that it can rotate between 0 degrees and 180 degrees around one axis so as to be able to rotate forward and reverse, a motor that drives the rotating table, and a pair provided on the base portion The rotating table is positioned at a first indexing position corresponding to 0 degrees and a second indexing position corresponding to 180 degrees. A numerical control device for controlling a rotary table device provided with a pair of positioning portions for
The motor is driven to rotate the rotary table in one direction, one of the pair of positioning portions is brought into contact with one of the pair of stopper portions, and the rotary table is positioned at the first index position. And provisionally determining means for temporarily determining the position of the rotary table as a reference position;
After the temporary determining means positions the position of the rotary table at the first index position, the motor is driven to rotate the rotary table in the direction opposite to the one direction, and the other is different from the one. The first positioning means for abutting the positioning portion of the rotary table to the second indexing position, abutting against the other stopper portion different from the one,
First position storage means for storing a first position of the motor when the first positioning means positions the rotary table at the second index position;
Second positioning means for driving the motor, rotating the rotary table in the one direction, and abutting the one positioning portion on the one stopper portion to position the rotary table at the first index position. When,
Second position storage means for storing a second position of the motor when the second positioning means positions the rotary table at the first index position;
The difference for calculating the difference between the measured amount between the first position stored in the first position storage means and the second position stored in the second position storage means and the reference amount corresponding to 180 degrees. A quantity calculating means;
A numerical control apparatus comprising: a changing unit that shifts and changes the reference position by an equal amount obtained by dividing the difference amount calculated by the difference amount calculating unit into two. Based on a first control command for instructing positioning to a first target position corresponding to the first index position, the motor is driven to rotate the rotary table in the one direction, and the one positioning unit The first deviation amount, which is the difference between the actual position of the rotary table and the first target position when the rotary table is positioned at the first index position by contacting the one stopper portion, is calculated. First deviation amount calculating means for
Based on a second control command that instructs positioning to a second target position corresponding to the second index position, the motor is driven to rotate the rotary table in the opposite direction, and the other positioning unit The second deviation amount, which is the difference between the actual position of the rotary table and the second target position when the rotary table is positioned at the second index position by contacting the other stopper portion, is calculated. Second deviation amount calculating means for performing,
Difference determining means for determining whether or not a difference amount between the first deviation amount calculated by the first deviation amount calculating means and the second deviation amount calculated by the second deviation amount calculating means is a predetermined value or more;
A reference position changing means for shifting and changing the reference position by an equal amount obtained by dividing the difference amount determined by the difference determining means,
When the difference determining means determines that the difference amount is equal to or greater than the predetermined value, the reference position changing means shifts the reference position, the first deviation amount calculating means, the second deviation amount calculating means, and the difference determining means. The numerical control apparatus according to claim 1, further comprising: a re-execution unit that executes each of the processes again. Counting means for counting the number of times the re-execution means executes the processes;
Number-of-times determining means for determining whether the count value of the counting means is equal to or greater than a predetermined number of times;
The numerical control apparatus according to claim 2, further comprising a notifying unit that notifies an abnormality when the count determining unit determines that the count value is equal to or greater than the predetermined number. The first target position is a position shifted in the one direction from the first index position,
4. The numerical control device according to claim 1, wherein the second target position is a position shifted in the opposite direction from the second index position. 5. A rotating table that supports the base portion so that it can rotate between 0 degrees and 180 degrees around one axis so as to be able to rotate forward and reverse, a motor that drives the rotating table, and a pair provided on the base portion The rotating table is positioned at a first indexing position corresponding to 0 degrees and a second indexing position corresponding to 180 degrees. A rotary table position adjustment method performed by a numerical controller that controls a rotary table device including a pair of positioning units that includes:
The motor is driven to rotate the rotary table in one direction, one of the pair of positioning portions is brought into contact with one of the pair of stopper portions, and the rotary table is positioned at the first index position. A provisional determination step of provisionally determining the position of the rotary table as a reference position;
After positioning the rotary table at the first indexing position in the provisional determination step, the motor is driven to rotate the rotary table in a direction opposite to the one direction. A first positioning step of positioning the rotary table at the second index position by contacting the other different positioning portion with the other stopper portion different from the one;
A first position storing step of storing a first position of the motor when the rotary table is positioned at the second index position in the first positioning step;
A second positioning step of driving the motor to rotate the rotary table in the one direction, and abutting the one positioning portion against the one stopper portion to position the rotary table at the first index position. When,
A second position storage step of storing a second position of the motor when the rotary table is positioned at the first index position in the second positioning step;
Calculate the difference between the measured amount between the first position stored in the first position storing step and the second position stored in the second position storing step and the reference amount corresponding to 180 degrees. Difference amount calculation step to perform,
A rotation table position adjusting method comprising: a changing step of shifting and changing the reference position by an equal amount obtained by dividing the difference amount calculated in the difference amount calculating step.

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