JP7727269B2 - Control device and control method - Google Patents

Description

The present invention relates to a control device and a control method.

A conventional machine tool comprises a cover, a machine body, a work table, and a partition wall. The cover houses the machine body, work table, and partition wall. The work table can be rotated around an axis parallel to the vertical direction by the power of a motor. The work table has a pair of fixing devices on its upper surface. The workpiece is fixed to one or both of the pair of fixing devices. The fixing devices can change the position of the workpiece relative to the work table by the power of a motor. The partition wall divides the interior of the cover into a preparation area and a processing area. The machine body is installed in the processing area. When one fixing device is in the preparation area, the other fixing device is in the processing area. The machine tool processes the workpiece fixed by the fixing device on the machine body side that is in the processing area. While the machine body processes the workpiece, the machine tool can change the workpiece in the fixing device in the preparation area and adjust the position of the workpiece.

Japanese Patent Application Laid-Open No. 2020-52610

The control device that controls the above-mentioned machine tool returns the pair of clamping devices to their home positions based on a command to perform a home position return in manual operation mode. Even when the control device has already completed adjusting the workpiece placement on the clamping devices in the preparation area, it returns the clamping devices in the preparation area to their home positions in addition to the clamping devices in the machining area based on a command to perform a home position return in manual operation mode. Therefore, when the control device performs a home position return in manual operation mode after completing adjustment of the workpiece placement on the clamping devices in the preparation area, the operator must again readjust the workpiece placement, which is cumbersome.

The present invention aims to provide a control device and control method that can reduce the effort required to readjust the position of the workpiece in the fixed device in the preparation area when issuing a command to return to the origin in manual operation mode.

The control device of claim 1 of the present invention includes a cover surrounding the periphery of a machine body, a partition wall dividing the interior of the cover into a machining area and a preparation area, a work table provided below the partition wall, a pair of fixing devices provided on the work table for fixing a workpiece so that its position relative to the work table can be changed, a moving device for changing the position of the work table between a first position where one of the fixing devices is in the machining area and the other of the fixing devices is in the preparation area when the one of the fixing devices is in the preparation area and a second position where the other of the fixing devices is in the machining area when the one of the fixing devices is in the preparation area, a table detection unit for outputting a detection result of the position of the work table, and a moving device for changing the position of the work table between a first position where one of the fixing devices is in the machining area and the other of the fixing devices is in the machining area when the one of the fixing devices is in the preparation area. A control device for controlling a machine tool including a machine main body for machining the workpiece fixed by the fixing device located in the machining area, the machine main body being provided in a position on the work table, the pair of fixing devices each having a motor that fixes the workpiece so that its position relative to the work table can be changed by driving the motor, and the control device includes: a command acquisition unit that acquires a return-to-origin command that commands a fixing device selected from the pair of fixing devices to return to its origin; and a return-to-origin execution unit that, when the command acquisition unit acquires the return-to-origin command, drives the motor of the fixing device selected from the pair of fixing devices to return the fixing device to its origin. The control device of claim 1 can execute return-to-origin only for the fixing device located in the machining area when the fixing device selected from the pair of fixing devices is located in the machining area. The control device prevents the operator from unintentionally returning to its origin a fixing device located in the preparation area , thereby reducing the effort required to readjust the position of the workpiece of the fixing device located in the preparation area.

The machine tool controlled by the control device of claim 2 of the present invention further includes a door provided on at least one of the side of the cover and the partition wall, and a door detector that outputs the open/closed state of the door, and the origin return execution unit halts the execution of the origin return of the return target in accordance with the open/closed state of the door output by the door detector. The control device of claim 2 can reliably avoid executing the origin return of the return target in situations where it is inappropriate to execute the origin return of the return target, based on the open/closed state of the door.

The table detection unit of the machine tool controlled by the control device of claim 3 of the present invention outputs the detection result when the work table is at the first position or the second position, and the origin return execution unit halts the execution of the origin return of the return target when the detection result of the table detection unit has not been acquired when the command acquisition unit acquires the origin return command. The control device of claim 3 can prevent the execution of the origin return of the return target when the detection result of the table detection unit has not been acquired and the work table is in the middle of movement between the first position and the second position.

The doors of the machine tool controlled by the control device of claim 4 of the present invention include an outer door provided on the preparation area side of the partition wall inside the cover, an inner door provided on the partition wall, and a side door extending in a direction intersecting the partition wall inside the cover, and the door detector individually detects the open/closed states of the outer door, inner door, and side door, and when the return-to-origin execution unit determines that the return target is the fixed device located in the machining area, the return-to-origin execution unit executes the return-to-origin of the pair of fixed devices if the inner door, side door, and outer door output by the door detector are all in a closed state and the detection result of the platform detection unit has not been acquired when the command acquisition unit acquires the return-to-origin command. The control device of claim 4 can regard the processing area and preparation area as one continuous area and return the pair of fixed devices to their home positions, even if the target for return is a fixed device located in the processing area. If the inner door, side door, and outer door output from the door detector are all closed, and the detection results from the platform detection unit have not yet been obtained when the return-to-home command is received, the control device can treat the processing area and preparation area as one continuous area and return the pair of fixed devices to their home positions.

The control device of claim 5 of the present invention further includes a signal acquisition unit that acquires, for each of the pair of fixing devices, an OFF signal that permits driving of the motor and an ON signal that prohibits driving of the motor from an external device, and the origin return execution unit halts the execution of origin return of the return targets when the command acquisition unit acquires the origin return command and at least one of the return targets has acquired the ON signal. The control device of claim 5 can reliably avoid executing origin return for the return targets when an ON signal is acquired for at least one of the return targets from an external device.

The pair of fixing devices of the machine tool controlled by the control device of claim 6 of the present invention each include a turntable that changes the cutting surface of the workpiece by driving the motor, and when the command acquisition unit acquires the return to origin command, the origin return execution unit drives the motor of the target to return the turntable to the origin. The control device of claim 6 can execute the return to origin of the target turntable by driving the motor of the target in response to acquiring the return to origin command.

The control method of claim 7 of the present invention includes a cover surrounding the periphery of the machine body, a partition wall dividing the interior of the cover into a machining area and a preparation area, a work table provided below the partition wall, a pair of fixing devices provided on the work table for fixing a workpiece so that its position relative to the work table can be changed, a moving device for changing the position of the work table between a first position in which one of the fixing devices is in the preparation area when the other of the fixing devices is in the machining area and a second position in which the other of the fixing devices is in the machining area when the one of the fixing devices is in the preparation area, a table detection unit for outputting the detection result of the position of the work table, and a moving device provided in the machining area and configured to detect the position of the work table. A control method performed by a control device controlling a machine tool that includes a machine main body that processes the workpiece fixed by the fixing device located in a machining area, wherein the pair of fixing devices each have a motor, and that fixes the workpiece so that its position relative to the work table can be changed by driving the motor, the control method comprising: a command acquisition step of acquiring a return-to-origin command that commands a fixing device selected from the pair of fixing devices to return to its origin; and a return-to-origin execution step of, when the return-to-origin command is acquired in the command acquisition step, driving the motor of the fixing device selected from the pair of fixing devices to return the fixing device to its origin. A control device that executes the control method of claim 7 achieves the same effects as the control device of claim 1.

FIG. FIG. 3 is a perspective view of the inside of the cover 3 of the machine tool 1. FIG. 2 is a block diagram of the electrical configuration of the control device 50 and the machine tool 1. Flow chart of the main process. 10A to 10C are diagrams illustrating conditions and results of returning to the origin in specific examples 1 to 17.

The configuration of the machine tool 1 controlled by the control device 50 will be described. The following description will use the left-right, front-back, and up-down directions indicated by arrows in the diagram. The left-right, front-back, and up-down directions of the machine tool 1 correspond to the X-axis, Y-axis, and Z-axis directions of the machine tool 1, respectively.

As shown in Figures 1 and 2, the machine tool 1 comprises a base 2, a cover 3, a workbench 9, a pair of fixing devices 70, 80, a moving device 90, and a machine body 8. The base 2 is located at the bottom of the machine tool 1. The cover 3 is located at the top of the base 2 and surrounds the machine body 8, preventing chips and cutting fluid from scattering to the surrounding area. The cover 3 comprises an outer door 56, a side door 57, an operation panel 17, a partition wall 60, and an inner door 64. The outer door 56 is located on the front of the cover 3 and is movable left and right, opening and closing an opening 58 in the center of the front of the cover 3. Figure 1 shows the outer door 56 in an open state. The side door 57 is located on the right side of the cover 3 and is movable back and forth, opening and closing an opening 59 in the center of the right side of the cover 3. The operation panel 17 is located to the right of the outer door 56. The operation panel 17 is vertically long and rectangular when viewed from the front. The operation panel 17 has a display unit 19 in the upper half of its front surface and an input unit 18 in the lower half of its front surface. The display unit 19 is a vertically elongated rectangle when viewed from the front, and is an input device that can display various screens and input various information by pressing the screen display. The input unit 18 has various switches. The operation panel 17 accepts input of various operation instructions for the machine tool 1 via the display unit 19 and input unit 18. The partition wall 60 is a wall extending left and right inside the cover 3, and divides the interior of the cover 3 into a machining area R1 and a preparation area R2. The machining area R1 is the area on the side of the partition wall 60 where the machine body 8 is located. The preparation area R2 is the area on the side of the partition wall 60 where the outer door 56 is located. The inner door 64 is movable left and right on the front of the partition wall 60 and opens and closes an opening 65 in the center of the partition wall 60.

The work table 9 is located inside the cover 3, below the partition wall 60. The work table 9 extends parallel to the horizontal direction at the front of the top surface of the base 2. The work table 9 is rectangular in plan view. A partition plate 95 extending perpendicular to the work table 9 is fixed to the top surface of the work table 9. When the partition plate 95 faces left and right, the partition plate 95, together with the partition wall 60, divides the inside of the cover 3 into a processing area R1 and a preparation area R2. The work table 9 rotates around the vertical axis M.

The fixing devices 70 and 80 are removably mounted on the work table 9. The fixing devices 70 and 80 fix the workpiece to the work table 9 so that its position can be changed. In Figure 1, the pair of fixing devices 70 and 80 have been removed from the work table 9. In Figure 2, the fixing device 70 is located in the machining area R1, and the fixing device 80 is located in the preparation area R2. The fixing device 70 comprises a rotating table 71, a fixing device motor 72, an encoder 73 (see Figure 3), a support portion 74, and a clamping portion 75. The rotating table 71 is plate-shaped and long from side to side. The fixing device motor 72 is a servo motor. The output shaft of the fixing device motor 72 is connected to one end of the rotating table 71. The support portion 74 is located spaced apart from the fixing device motor 72 on the left and right, and supports the other end of the rotating table 71. The clamping portion 75 is located on the top surface of the rotating table 71. The clamping unit 75 manually or automatically secures and releases the workpiece using compressed air supplied by a compressor. The rotating table 71 rotates around axis A1 driven by the clamping device motor 72, changing the cutting surface of the workpiece fixed to the rotating table 71. The fixing device 80 has a similar configuration to the fixing device 70 and includes a rotating table 81, a fixing device motor 82, an encoder 83 (see Figure 3), a support unit 84, and a clamping unit 85. The rotating table 81 rotates around axis A2 extending left and right driven by the clamping device motor 82, changing the cutting surface of the workpiece fixed to the rotating table 81.

The moving device 90 changes the position of the work table 9 between a first position and a second position. The first position shown in Figure 2 is a position where the fixing device 70 is in the processing area R1 and the fixing device 80 is in the preparation area R2. The second position (not shown) is a position where the fixing device 70 is in the preparation area R2 and the fixing device 80 is in the processing area R1. The moving device 90 of this embodiment is equipped with a work table motor 92 (see Figure 3), and changes the position of the work table 9 between the first position and the second position by rotating the work table 9 around the vertical axis M of the work table 9 using the power of the work table motor 92. When the work table 9 is in the first position or the second position, the axes A1 and A2 face left and right.

The machine body 8 is mounted on the upper part of the base 2 behind the workbench 9. It rotates the spindle 7, to which a tool is attached, to perform cutting on a workpiece fixed to a pair of fixing devices 70, 80 on the workbench 9. The machine body 8 comprises a pillar 5, a spindle head 6, a spindle 7, a movement mechanism 10, and an automatic tool changer 4 (hereinafter referred to as ATC 4). The pillar 5 is mounted on the base 2 so that it can move forward, backward, left, and right. The spindle head 6 is mounted on the pillar 5 so that it can move up and down, and rotatably supports the spindle 7. The spindle 7 extends in the Z-axis direction and is rotated by the spindle motor 20 (see Figure 3). A tool holder is removably attached to the spindle 7, and the tool holder is locked and unlocked depending on the rotation angle of the ATC motor 25 (see Figure 3). The tool holder holds the tool.

The movement mechanism 10 movably supports the upright pillar 5. The movement mechanism 10 moves the upright pillar 5 in the X-axis direction by rotational driving of the X-axis motor 21 (see Figure 3). The movement mechanism 10 moves the upright pillar 5 in the Y-axis direction by driving of the Y-axis motor 22 (see Figure 3). The movement mechanism 10 moves the spindle head 6 in the Z-axis direction by driving of the Z-axis motor 23 (see Figure 3).

By driving the X-axis motor 21, Y-axis motor 22, and Z-axis motor 23, the movement mechanism 10 can move the spindle head 6 relative to the work table 9 in the X-, Y-, and Z-axis directions, thereby moving the spindle 7. The machine tool 1 drives the spindle motor 20 to rotate the spindle 7, to which a tool is attached, thereby machining the workpiece.

The electrical configuration of the machine tool 1 will be described with reference to Figure 3. The machine tool 1 is equipped with a control device 50 for controlling the machine tool 1. The control device 50 is equipped with a CPU 51, ROM 52, RAM 53, storage device 54, and input/output interface 55. The CPU 51 provides overall control of the control device 50. ROM 52 stores various programs. These programs include a main control program for executing the main processing (see Figure 4), which will be described later. RAM 53 stores various data used during processing. Storage device 54 is non-volatile memory, and stores NC programs, etc. NC programs include movement commands, machining commands, and tool change commands. The movement commands include the position coordinates of the spindle 7 and the movement speed of the spindle 7 between the position coordinates. The machining command includes the rotational speed of the spindle 7. The tool change command specifies the tool number of the tool to be attached to the spindle 7.

The input/output interface 55 is electrically connected to the input unit 18, display unit 19, spindle motor 20, X-axis motor 21, Y-axis motor 22, Z-axis motor 23, magazine motor 24, ATC motor 25, work table motor 92, fixing device motors 72 and 82, outer door detector 61, side door detector 62, inner door detector 63, encoders 30-35, 73 and 83, and platform detector 93. In response to operator operation, the input unit 18 can output input signals, including a return-to-origin command (described below), to the input/output interface 55. The input/output interface 55 is connected to an external device K, and receives from the external device K an OFF signal permitting operation and an ON signal prohibiting operation for each of the pair of fixing devices 70 and 80. Operation refers to the driving of the fixing device motors 72 and 82.

The outer door detector 61 outputs the open/closed state of the outer door 56. The side door detector 62 outputs the open/closed state of the side door 57. The inner door detector 63 outputs the open/closed state of the inner door 64. The door detectors 61 to 63 are composed of limit switches, etc., and individually detect the open/closed states of the outer door 56, side door 57, and inner door 64. The encoder 30 is provided on the main shaft motor 20 and detects the rotation angle of the main shaft motor 20. The encoder 31 is provided on the X-axis motor 21 and detects the rotation angle of the X-axis motor 21. The encoder 32 is provided on the Y-axis motor 22 and detects the rotation angle of the Y-axis motor 22. The encoder 33 is provided on the Z-axis motor 23 and detects the rotation angle of the Z-axis motor 23. The encoder 34 is provided on the magazine motor 24 and detects the rotation angle of the magazine motor 24. The encoder 35 is provided on the ATC motor 25 and detects the rotation angle of the ATC motor 25. The platform detector 93 outputs a detection result when the workbench 9 is in the first position or the second position. The platform detector 93 is a proximity switch that detects a detection target (protrusion) on the workbench 9. The protrusion and platform detector 93 are positioned so that the platform detector 93 can detect when the workbench 9 is in the first position or the second position. The encoder 73 is provided on the fixing device motor 72 and detects the rotation angle of the fixing device motor 72. The encoder 83 is provided on the fixing device motor 82 and detects the rotation angle of the fixing device motor 82. Although the platform detector 93 is configured as the platform detector, an encoder may also be provided on the workbench motor 92, and whether the workbench 9 is in the first position or the second position may be detected based on the rotation angle of the workbench motor 92 detected by the encoder.

With reference to Figures 4 and 5, the main processing will be explained using specific examples 1 to 17. When issuing an instruction to perform a return to origin in manual operation mode, the operator operates the input unit 18 to select the return target from the pair of fixing devices 70, 80 and input a return to origin command. The return target in the main processing in this embodiment is the pair of fixing devices 70, 80 or the fixing device located in the machining area R1. The fixing device located in the machining area R1 is determined according to the position of the work table 9. As shown in Figure 2, when the work table 9 is in the first position, the fixing device located in the machining area R1 is fixing device 70. When the work table 9 is in the second position, the fixing device located in the machining area R1 is fixing device 80. Upon receiving a return to origin command based on the input signal output by the input unit 18, the CPU 51 reads a program stored in ROM 52 and starts the main processing. The CPU 51 performs the processing of specific examples 1 to 17 at different times, but for simplicity's sake, the processing of specific examples 1 to 17 will be explained in parallel below. When the operator presses the origin return command key provided on the input unit 18, the CPU 51 acquires the origin return command.

In the "Outer Door" column in Figure 5, "Closed" indicates when the outer door 56 is closed, and "Open" indicates when the outer door 56 is open. In the "Inner Door, Side Door" column, "Closed" indicates when both the side door 57 and the inner door 64 are closed, and "Open" indicates when at least one of the side door 57 and the inner door 64 is open. In the "Work Table Position" column, "Not Acquired" indicates when the platform detector 93 has not yet output the detection result of the work table position, and "Acquired" indicates when the detection result has been output. The "operation signal" column indicates when an OFF signal is being received from the external device K for both of the pair of fixing devices 70, 80 by "both OFF," when an ON signal is being received by the fixing device in the machining region R1 and an OFF signal is being received by the fixing device in the preparation region R2 by "machining region ON," when an OFF signal is being received by the fixing device in the machining region R1 and an ON signal is being received by the fixing device in the preparation region R2 by "preparation region ON," and when an ON signal is being received by both of the pair of fixing devices 70, 80 by "both ON." The "origin return" column indicates when origin return is being performed for both of the pair of fixing devices 70, 80 by "both executed," when origin return is being performed for the fixing device in the machining region R1 by "machining region executed," and when origin return of the return target is canceled by "cancelled." The external device K is, for example, a sequencer, a PLC (programming logic controller), a switch, etc.

As shown in FIG. 4, the CPU 51 receives an origin return command based on an input signal output by the input unit 18, instructing the return target, a fixed device selected from the pair of fixed devices 70 and 80, to return to the origin (S1). The CPU 51 determines whether the return target of the origin return command is the pair of fixed devices 70 and 80 (S2). In specific examples 1 to 8, the return target is the pair of fixed devices 70 and 80 (S2: YES). The CPU 51 determines whether the outer door 56, side door 57, and inner door 64 are all closed based on the detection results of the door detectors 61 to 63 (S3). In specific examples 1 to 5, the outer door 56, side door 57, and inner door 64 are all closed (S3: YES). The CPU 51 determines whether an OFF signal is being received from the external device K for the return target (S8). The CPU 51 stores the signal received from the external device K in the storage device 54 as a process executed separately from the main process. The CPU 51 performs S8 by referring to the storage device 54. In specific examples 1 and 2, an OFF signal is being received from external device K for both of the pair of holding devices 70, 80 that are the return targets (S8: YES), and in response to receiving the origin return command in S1, the CPU 51 drives the holding device motors 72, 82 of the pair of holding devices 70, 80 that are the return targets, and executes the return to origin of the pair of holding devices 70, 80 (S9). Specifically, the CPU 51 drives the holding device motors 72, 82 that are the return targets, and returns the turntables 71, 81 of the pair of holding devices 70, 80 that are the return targets to their origins.

In specific examples 6 to 8, at least one of the outer door 56, side door 57, and inner door 64 is open (S3: NO), and the CPU 51 suspends the execution of the return to origin of the pair of fixing devices 70, 80 to be returned, depending on the open/closed state of the outer door 56, side door 57, and inner door 64 output by the door detectors 61 to 63 (S11). The CPU 51 displays a warning on the display unit 19 that return to origin is not possible. The CPU 51 may also display the reason why return to origin is not possible on the display unit 19 in S11. In specific examples 3 to 5, when the return to origin command is received in S1, at least one of the fixing devices to be returned has received an ON signal (S8: NO), and the CPU 51 suspends the execution of the return to origin of the pair of fixing devices 70, 80 to be returned (S11).

In specific examples 9 to 17, the target for return is not a pair of fixed devices 70, 80 (S2: NO), so the CPU 51 determines whether the side door 57 and inner door 64 are all closed based on the detection results of the door detectors 62, 63 (S4). In specific examples 15 and 16, at least one of the side door 57 and inner door 64 is open (S4: NO), and the CPU 51 halts the execution of the return to origin of the fixed device 70 located in the processing area R1, which is the target for return, based on the door open/close states output by the door detectors 61 to 63 (S11). In specific examples 9 to 14 and 17, the side door 57 and inner door 64 are all closed (S4: YES), so the CPU 51 determines whether the outer door 56 is closed and the work table position has not yet been acquired from the table detector 93 based on the detection results of the door detector 61 and table detector 93 (S5). The platform detector 93 outputs the platform position when the platform 9 is in the first position or the second position, and does not output the platform position when the platform 9 is in the process of moving from the first position to the second position or from the second position to the first position.

In specific example 10, the outer door 56 is closed and the work table position has not yet been obtained from the table detector 93 (S5: YES), and the CPU 51 determines whether an OFF signal is being received from the external device K for the return target (S8). In specific example 10, an OFF signal is being received from the external device K for the return target (S8: YES), and in response to receiving the origin return command in S1, the CPU 51 drives the fixing device motors 72, 82 of the pair of fixing devices 70, 80 to return the pair of fixing devices 70, 80 to their origins (S9). As a result of the above, when the target to be returned is the fixed device 70 located in the processing area R1 shown in Figure 2, if the outer door 56, side door 57, and inner door 64 output by the door detectors 61-63 are all closed, and the detection result of the platform detector 93 has not yet been obtained when S1 obtains the return to origin command (S2: NO, S4: YES, S5: YES), the CPU 51 executes the return to origin of the pair of fixed devices 70, 80 (S9).

Specific examples 9, 11-14, and 17 do not satisfy the conditions that the outer door 56 is closed and the work table position has not yet been acquired from the platform detector 93 (S5: NO), so the CPU 51 determines whether the work table position has been acquired (S6). Specific example 17 does not obtain the detection result of the platform detector 93 when the origin return command is received (S6: NO), so the CPU 51 cancels the execution of origin return for the return target (S11).

In Examples 9, 11, and 14, the workbench position has already been acquired (S6: YES), and the CPU 51 determines whether an OFF signal is being received from the external device K for the object to be returned (S7). In Examples 9, 12, and 14, an OFF signal is being received from the external device K for the fixed device 70 located in the machining area R1 that is the object to be returned (S7: YES). When the CPU 51 receives a return-to-origin command in S1, it drives the fixed device motor 72 of the fixed device 70 located in the machining area R1 that is the object to be returned to the origin (S10). In Examples 11 and 13, when the return-to-origin command is received in S1, the fixed device 70 located in the machining area R1 that is the object to be returned has acquired an ON signal (S7: NO), so the CPU 51 cancels the execution of the return-to-origin for the object to be returned (S11). After any of S9 to S11, the CPU 51 then ends the main processing.

In the above embodiment, the control device 50, machine tool 1, cover 3, machine body 8, workbench 9, partition wall 60, moving device 90, and platform detector 93 are examples of the control device, machine tool, cover, machine body, workbench, partition wall, moving device, and platform detector of the present invention, respectively. Fixing devices 70 and 80 are an example of a pair of fixing devices of the present invention. Rotating tables 71 and 81 are an example of a rotating table of the present invention. Fixing device motors 72 and 82 are an example of a motor of the present invention. The machining area R1 and preparation area R2 are examples of the machining area and preparation area of the present invention, respectively. The outer door 56, side door 57, and inner door 64 are examples of the outer door, side door, and inner door of the present invention, respectively. Door detectors 61-63 are examples of door detectors of the present invention. The input/output interface 55 is an example of a signal acquisition unit of the present invention. The CPU 51 that performs S1 is an example of a command acquisition unit of the present invention. The CPU 51 that executes S9 and S10 is an example of a return-to-origin execution unit of the present invention.

The control device 50 of the above embodiment controls a machine tool 1 including a cover 3, a partition wall 60, a work table 9, a pair of fixing devices 70, 80, a moving device 90, a table detector 93, and a machine body 8. The cover 3 is box-shaped and surrounds the machine body 8. The partition wall 60 divides the interior of the cover 3 into a machining region R1 and a preparation region R2. The pair of fixing devices 70, 80 are provided on the work table 9, which is provided below the partition wall 60, and fix a workpiece so that its position relative to the work table 9 can be changed. The moving device 90 changes the position of the work table 9 between a first position where one fixing device is in the machining region R1 and the preparation region R2 when the other fixing device is in the preparation region R2, and a second position where the other fixing device is in the machining region R1 when the other fixing device is in the preparation region R2. The table detector 93 outputs the detection result of the position of the work table 9. The machine main body 8 is provided in the machining region R1 and machines a workpiece fixed by a fixing device located in the machining region R1. Each of the pair of fixing devices 70, 80 has a fixing device motor 72, 82, which are driven to fix the workpiece so that its position relative to the worktable 9 can be changed. The CPU 51 of the control device 50 acquires an origin return command that commands a fixing device selected from the pair of fixing devices 70, 80 to return to its origin (S1). When the origin return command is acquired in S1, the CPU 51 drives the fixing device motor 72, 82 of the fixing device selected from the pair of fixing devices 70, 80 to return the fixing device to its origin (S9, S10). If the fixing device selected from the pair of fixing devices 70, 80 is located in the machining region R1 (S2: NO), the control device 50 can execute origin return only for the fixing device located in the machining region R1 (S10). The control device 50 prevents the fixing device in the preparation area R2 from being unintentionally returned to its origin by the operator, thereby reducing the effort required to readjust the position of the workpiece in the fixing device in the preparation area R2.

The control device 50 controls the machine tool 1, which further includes an outer door 56, a side door 57, and an inner door 64 provided on at least one of the side surfaces of the cover 3 and the partition wall 60, and door detectors 61-63 that output the open/closed status of the outer door 56, side door 57, and inner door 64. The CPU 51 halts the execution of the return to origin of the return target (S11) depending on the open/closed status of the outer door 56, side door 57, and inner door 64 output by the door detectors 61-63 (S3: NO, S4: NO). Based on the open/closed status of the doors, the control device 50 can reliably avoid executing the return to origin of the return target in situations where it is inappropriate to do so.

The platform detector 93 of the machine tool 1 controlled by the control device 50 outputs a detection result when the work platform 9 is in the first position or the second position. If the detection result of the platform detector 93 has not been obtained when the CPU 51 receives the origin return command in S1 (S6: NO), it cancels the execution of origin return for the return target (S11). The control device 50 can prevent the execution of origin return for the return target when the detection result of the platform detector 93 has not been obtained and the work platform 9 is in the middle of movement between the first position and the second position.

The machine tool 1 controlled by the control device 50 has an outer door 56 located on the preparation area R2 side of the partition wall 60 inside the cover 3, an inner door 64 located on the partition wall 60, and a side door 57 extending in a direction intersecting the partition wall 60 inside the cover 3. The door detectors 61-63 of the machine tool 1 individually detect the open/closed states of the outer door 56, inner door 64, and side door 57. When the target for return is a fixed device located in the machining area R1 (S2: NO), the CPU 51 executes return to origin of the pair of fixed devices 70, 80 (S9) if the conditions are met: the inner door 64, side door 57, and outer door 56 output by the door detectors 61-63 are all closed, and the detection result of the platform detector 93 has not yet been obtained when the return to origin command was received in S1 (S4: YES or S5: YES). Even if the target for return is a fixed device located in the processing area R1, if the inner door 64, side door 57, and outer door 56 output by the door detectors 61-63 are all closed, and the detection result of the platform detector 93 has not yet been obtained when the return to origin command is obtained in S1 (S4: YES or S5: YES), the control device 50 can regard the processing area R1 and preparation area R2 as a single continuous area and perform the return to origin of the pair of fixed devices 70, 80.

The control device 50 has an input/output interface 55 that receives from the external device K an OFF signal that allows the driving of the holding device motors 72, 82 for each of the pair of holding devices 70, 80, and an ON signal that prohibits the driving of the holding device motors 72, 82. When the CPU 51 receives the origin return command in S1, if at least one of the return targets has received an ON signal (S8: NO or S7: NO), it halts the execution of origin return for the return targets (S11). The control device 50 can reliably avoid executing origin return for the return targets when it receives an ON signal for at least one of the return targets from the external device K.

The pair of holding devices 70, 80 of the machine tool 1 controlled by the control device 50 each include a turntable 71, 81 that changes the cutting surface of the workpiece by driving the holding device motors 72, 82. When the CPU 51 acquires a return-to-origin command in S1, it drives the holding device motors 72, 82 to return the turntables 71, 81 to their origins. In response to acquiring the return-to-origin command, the control device 50 can drive the holding device motors 72, 82 to return the turntables 71, 81 to their origins.

The control device and control method of the present invention can be modified in various ways in addition to the above-described embodiment. The present invention may be applied to categories other than control devices such as the control program for the machine tool 1 and storage media storing the control program. The control device 50 may be the same device as the machine tool 1, or a different device. The control device 50 may be the same device as the external device K, or a different device. The configuration of the machine tool 1 may be modified as appropriate. The machine tool 1 may be capable of mounting only one type of tool. The machine tool 1 may not have at least one of the outer door 56, side door 57, and inner door 64, or may have a door other than the outer door 56, side door 57, and inner door 64. The machine tool 1 may not have at least one of the door detectors 61-63, or may have a door detector that detects the open/closed state of a door other than the outer door 56, side door 57, and inner door 64. The opening and closing method of each door may be modified as appropriate. The moving device 90 may move the workbench 9 parallel to the first position and the second position. The platform detector 93 may be capable of detecting the position of the worktable 9 when it is between the first and second positions. The platform detector 93 may detect the position of the worktable 9 mechanically or optically. Instead of the detection result from the platform detector 93, the control device 50 may acquire, as the position of the worktable 9, coordinate values indicating the position of the worktable 9 stored in the memory device 54 based on the output value to the worktable motor 92. The fixing devices 70, 80 may have the same configuration as each other or different configurations. The fixing devices 70, 80 each have a motor and can fix the workpiece so that its position relative to the worktable 9 can be changed by driving the motor. The fixing devices 70, 80 may be capable of moving the position of the workpiece parallel to the worktable 9 by driving the fixing device motors 72, 82, or may be capable of rotating the workpiece around an axis intersecting the worktable 9. The machine tool 1 may be provided with at least one pair of fixing devices 70, 80, and may be provided with three or more fixing devices arranged on the worktable 9.

The program for the control device 50 to perform control processing may be stored in the storage device 54 of the control device 50 before the CPU 51 executes the program. Therefore, the program acquisition method, acquisition route, and device storing the program may each be changed as appropriate. The program executed by the CPU 51 may be received from another device via cable or wireless communication and stored in a storage device such as flash memory. The other device may include, for example, a PC or a server connected via a network.

Some or all of the processing performed by the control device 50 may be performed by an electronic device (e.g., an ASIC) separate from the CPU 51. The processing performed by the control device 50 may be distributed among multiple electronic devices (e.g., multiple CPUs). The order of each step in the processing performed by the control device 50 may be changed, steps may be omitted, or steps may be added as necessary. The scope of the present invention also includes embodiments in which an operating system (OS) running on the control device 50 performs some or all of the processing at the command of the CPU 51. For example, the following modifications may be made to the above embodiment as appropriate.

The control device 50 does not need to abort the origin return in response to the acquisition of an origin return command. The control device 50 may execute the origin return without aborting it depending on the open/closed state of the outer door 56, side door 57, and inner door 64. The control device 50 may execute the origin return without aborting it if the detection result of the platform detector 93 has not yet been acquired when the origin return command is acquired. When the return target is a fixed device located in the processing area R1, the control device 50 may abort the origin return if the detection result of the platform detector 93 has not yet been acquired when the return target is acquired in S1. The input/output interface 55 of the control device 50 does not need to receive an ON/OFF signal from the external device K. In this case, the control device 50 does not need to determine whether to abort the execution of the origin return of the return target in response to a signal from the external device K. The control device 50 may abort the return of the return target to the origin when the return target is a pair of fixed devices 70, 80 and the position of the work table 9 has not yet been acquired. The control device 50 may perform the process in S5 by determining whether the work table 9 is in the first position or the second position based on coordinate values indicating the position of the work table 9, instead of the detection results of the table detector 93. The control device 50 may also be able to select a fixed device in the preparation area R2 as the return target.

1: Machine tool 3: Cover 8: Machine body 9: Work table 50: Control device 51: CPU
55: Input/output interface 56: outer door 57: side door 60: partition walls 61 to 63: door detector 64: inner door 70, 80: fixing devices 71, 81: rotating tables 72, 82: fixing device motor 90: moving device 93: table detector K: external device R1: processing area R2: preparation area

Claims (7)

A cover that surrounds the machine body;
a partition wall that divides the interior of the cover into a processing area and a preparation area;
a workbench provided below the partition wall;
a pair of fixing devices provided on the work table for fixing a workpiece so that its position relative to the work table can be changed;
a moving device that changes the position of the work table between a first position where one of the fixing devices is in the processing area and the other of the fixing devices is in the preparation area and a second position where the other of the fixing devices is in the processing area when the one of the fixing devices is in the preparation area;
a platform detector that outputs a detection result of the position of the work platform;
a control device for controlling a machine tool provided in the machining area and including: a machine body that machines the workpiece fixed by the fixing device in the machining area,
each of the pair of fixing devices has a motor, and fixes the workpiece so that its position relative to the work table can be changed by driving the motor;
a command acquisition unit that acquires a return-to-origin command that commands a return target, which is a fixed device selected from the pair of fixed devices, to return to the origin;
a return-to-origin execution unit that, when the command acquisition unit acquires the return-to-origin command, drives the motor of the return target of the pair of fixing devices to execute return of the return target to the origin,
the platform detection unit outputs the detection result when the work platform is at the first position or the second position;
The control device is characterized in that the origin return execution unit cancels the execution of the origin return of the return target when the detection result of the platform detection unit has not been acquired when the command acquisition unit acquires the origin return command specifying the pair of fixing devices or the fixing device located in the processing area as the return target. The machine tool controlled by the control device includes:
a door provided on at least one of a side surface of the cover and the partition wall;
a door detector that outputs an open/closed state of the door;
The control device according to claim 1, characterized in that when the command acquisition unit acquires the origin return command specifying the pair of fixing devices or the fixing device located in the processing area as the return target, the origin return execution unit suspends the execution of the origin return of the return target in accordance with the open/closed state of the door output by the door detector. A cover that surrounds the machine body;
a partition wall that divides the interior of the cover into a processing area and a preparation area;
a workbench provided below the partition wall;
a pair of fixing devices provided on the work table for fixing a workpiece so that its position relative to the work table can be changed;
a moving device that changes the position of the work table between a first position where one of the fixing devices is in the processing area and the other of the fixing devices is in the preparation area and a second position where the other of the fixing devices is in the processing area when the one of the fixing devices is in the preparation area;
a platform detector that outputs a detection result of the position of the work platform;
the machine body that is provided in the processing area and processes the workpiece fixed by the fixing device in the processing area;
A control device for controlling a machine tool comprising:
each of the pair of fixing devices has a motor, and fixes the workpiece so that its position relative to the work table can be changed by driving the motor;
a command acquisition unit that acquires a return-to-origin command that commands a return target, which is a fixed device selected from the pair of fixed devices, to return to the origin;
a return-to-origin execution unit that, when the command acquisition unit acquires the return-to-origin command, drives the motor of the return target of the pair of fixing devices to execute return of the return target to the origin;
Equipped with
The machine tool controlled by the control device includes:
a door provided on at least one of a side surface of the cover and the partition wall;
a door detector that outputs an open/closed state of the door;
the door includes an outer door provided on the preparation area side of the partition wall inside the cover, an inner door provided on the partition wall, and a side door extending in a direction intersecting the partition wall inside the cover,
the door detector detects the open/closed states of the outer door, the inner door, and the side door individually;
The control device is characterized in that, when the return target is the fixed device located in the processing area, the origin return execution unit executes the origin return of the pair of fixed devices when the conditions that the inner door, the side door, and the outer door output by the door detector are all closed and the detection result of the platform detection unit has not been acquired when the command acquisition unit acquires the origin return command are satisfied. a signal acquisition unit configured to acquire, from an external device, an OFF signal that permits driving of the motor and an ON signal that prohibits driving of the motor, for each of the pair of fixing devices;
The control device according to any one of claims 1 to 3, characterized in that when the command acquisition unit acquires the origin return command specifying the pair of fixing devices or the fixing device located in the processing area as the return target, if at least one of the return targets acquires the ON signal, the origin return execution unit cancels the execution of the return of the return target. each of the pair of fixing devices includes a rotating table that changes the cutting surface of the workpiece by driving the motor;
The control device according to any one of claims 1 to 4, characterized in that when the command acquisition unit acquires the origin return command, the origin return execution unit drives the motor of the object to be returned to the origin of the rotating table of the object to be returned. A cover that surrounds the machine body;
a partition wall that divides the interior of the cover into a processing area and a preparation area;
a workbench provided below the partition wall;
a pair of fixing devices provided on the work table for fixing a workpiece so that its position relative to the work table can be changed;
a moving device that changes the position of the work table between a first position where one of the fixing devices is in the processing area and the other of the fixing devices is in the preparation area and a second position where the other of the fixing devices is in the processing area when the one of the fixing devices is in the preparation area;
a platform detector that outputs a detection result of the position of the work platform;
a machine body that is provided in the processing area and processes the workpiece fixed by the fixing device in the processing area,
a control method performed by a control device that controls a machine tool in which the pair of fixing devices each have a motor and fixes the workpiece so that its position relative to the work table can be changed by driving the motor,
a command acquisition step of acquiring a return-to-origin command for instructing a return target, which is a fixing device selected from the pair of fixing devices, to return to the origin;
and an origin return execution step of, when the origin return command is acquired in the command acquisition step, driving the motor of the object to be returned out of the pair of fixing devices to execute origin return of the object to be returned,
the platform detection unit outputs the detection result when the work platform is at the first position or the second position;
In the origin return execution process, when the origin return command for the pair of fixing devices or the fixing device located in the processing area as the return target is acquired in the command acquisition process, if the detection result of the platform detection unit has not been acquired, the execution of the origin return of the return target is stopped. A cover that surrounds the machine body;
a partition wall that divides the interior of the cover into a processing area and a preparation area;
a workbench provided below the partition wall;
a pair of fixing devices provided on the work table for fixing a workpiece so that its position relative to the work table can be changed;
a moving device that changes the position of the work table between a first position where one of the fixing devices is in the processing area and the other of the fixing devices is in the preparation area and a second position where the other of the fixing devices is in the processing area when the one of the fixing devices is in the preparation area;
a platform detector that outputs a detection result of the position of the work platform;
the machine body that is provided in the processing area and processes the workpiece fixed by the fixing device in the processing area;
Equipped with
a control method performed by a control device that controls a machine tool in which the pair of fixing devices each have a motor and fixes the workpiece so that its position relative to the work table can be changed by driving the motor,
a command acquisition step of acquiring a return-to-origin command for instructing a return target, which is a fixing device selected from the pair of fixing devices, to return to the origin;
an origin return execution step of driving the motor of the object to be returned out of the pair of fixing devices when the origin return command is acquired in the command acquisition step, and executing the origin return of the object to be returned;
Equipped with
The machine tool controlled by the control device includes:
a door provided on at least one of a side surface of the cover and the partition wall;
a door detector that outputs an open/closed state of the door;
the door includes an outer door provided on the preparation area side of the partition wall inside the cover, an inner door provided on the partition wall, and a side door extending in a direction intersecting the partition wall inside the cover,
the door detector detects the open/closed states of the outer door, the inner door, and the side door individually;
In the origin return execution step, when the return target is the fixed device located in the processing area, if the inner door, the side door, and the outer door output by the door detector are all in a closed state, and the detection result of the platform detection unit has not been acquired when the origin return command is acquired in the command acquisition step, the origin return of the pair of fixed devices is executed.