Control device and control method

Abstract

To provide a control device and a control method that are able to shorten a working time and prevent positional deviation of a workpiece.SOLUTION: A control device 7 controls a first moving mechanism for moving a workpiece, clamp mechanisms 80, 81 for clamping the first moving mechanism, and a second moving mechanism for moving a tool for machining the workpiece. In the control device, the second moving mechanism includes a shaft length moving mechanism that moves in a shaft length direction of a rotary shaft of the tool. The control device comprises a CPU 70 that determines whether or not a post-operation following an operation of the first moving mechanism is an operation of the shaft length moving mechanism, and executes, when it is determined to be the operation of the shaft length moving mechanism, the operation of the shaft length moving mechanism during an execution of the clamping operation.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a control device and a control method. [Background technology]

[0002] A machine tool uses a tool attached to a spindle to machine a workpiece held by a holder. When machining a workpiece, the tool or workpiece moves due to the driving of a drive shaft of the machine tool.

[0003] Patent Document 1 discloses a machine tool that includes three first drive axes for moving tools, two second drive axes for moving a workpiece, and a clamping mechanism that can fix the second drive axes; after the second drive axes have finished driving, the clamping mechanism fixes the second drive axes before machining the workpiece, thereby preventing the second drive axes from shifting in position due to vibrations that occur when machining the workpiece. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-198772 Summary of the Invention [Problem to be solved by the invention]

[0005] For example, in the machine tool described above, after one of the second drive axes is driven, a clamping operation is performed to fix the one of the second drive axes, but if the clamping operation is performed together with another operation that follows the driving of the one of the second drive axes, the operation time can be shortened. However, if one of the second drive axes is driven before the clamping operation of the other second drive axis is completed, the position of the one second drive axis may shift before the clamping operation, causing the position of the workpiece to also shift. However, the machine tool of Patent Document 1 does not take such problems into consideration and is unable to solve them.

[0006] An object of the present disclosure is to provide a control device and a control method that can reduce work time and prevent workpiece position deviation. [Means for solving the problem]

[0007] The control device of the present invention is a control device that controls a first moving mechanism for moving a workpiece, a clamping mechanism that clamps the first moving mechanism, and a second moving mechanism for moving a tool that processes the workpiece or a workpiece different from the first moving mechanism, wherein the second moving mechanism includes an axial length moving mechanism that moves in the axial length direction of the rotation axis of the tool, and is equipped with a judgment unit that judges whether the subsequent operation following the operation of the first moving mechanism is an operation of the axial length moving mechanism, and an execution unit that executes the operation of the axial length moving mechanism while the clamping operation is being performed if the judgment unit determines that it is an operation of the axial length moving mechanism.

[0008] In the present invention, the determination unit determines whether the subsequent operation is an operation of the axial length moving mechanism, and if the determination unit determines that it is an operation of the axial length moving mechanism, after the operation of the first moving mechanism, the execution unit executes an operation of the axial length moving mechanism that is unlikely to cause a shift in the position of the workpiece while performing the clamping operation, thereby shortening the operation time and preventing the position of the workpiece from shifting.

[0009] The control device of the present invention comprises a setting unit that sets a first instruction or a second instruction, and an instruction determination unit that determines whether the setting unit has set the first instruction or the second instruction, and the execution unit starts execution of the operation of the axial length moving mechanism during execution of the clamping operation when the instruction determination unit determines that the instruction set by the setting unit is the first instruction and the determination unit determines that the post-operation is an operation of the axial length moving mechanism, and the execution unit starts execution of the operation of either of the second moving mechanisms during execution of the clamping operation when the instruction determination unit determines that the instruction set by the setting unit is the second instruction.

[0010] In the present invention, when the instruction determination unit determines that the instruction set by the setting unit is the first instruction and the determination unit determines that the subsequent operation is an operation of the axial length moving mechanism, the execution unit starts the operation of the axial length moving mechanism during the execution of the clamping operation, thereby shortening the operation time and preventing the workpiece from shifting position. Furthermore, when the instruction determination unit determines that the instruction set by the setting unit is the second instruction, the execution unit starts the execution of an operation of any of the second moving mechanisms during the execution of the clamping operation, thereby enabling a reduction in the work time to be prioritized.

[0011] In the control device according to the present invention, the operation of the axial length movement mechanism and the operation of any one of the second movement mechanisms are movements that do not involve machining.

[0012] In the present invention, the execution unit executes the clamping operation in parallel only when the axis length movement mechanism or any of the second movement mechanisms is operating, which is a movement that does not involve machining, and does not execute the clamping operation in parallel when the movement involves machining, which is likely to cause a shift in the position of the workpiece. Therefore, it is possible to prevent the workpiece from shifting in position.

[0013] The control device according to the present invention includes a reading unit that reads each block from a plurality of blocks including one or more operations, and the determining unit performs the determination for each operation on the blocks read by the reading unit.

[0014] In this invention, the reading unit reads each block from the stored program, and the judging unit judges each operation for the blocks read by the reading unit, thereby achieving high accuracy in reducing work time and preventing workpiece misalignment.

[0015] In the control device of the present invention, the execution unit executes the operation of the second movement mechanism related to the movement of the tool to a machining start position on the workpiece while the clamping operation is being performed, and after the clamping operation is completed, executes the operation of the second movement mechanism related to the movement of the tool accompanied by machining of the workpiece.

[0016] In the present invention, when the setting unit receives a parallel command, the execution unit executes the operation of the second movement mechanism related to the movement of the tool to the machining start position on the workpiece in parallel with the clamping operation, and executes the operation of the second movement mechanism related to the movement of the tool accompanying machining of the workpiece after the clamping operation is completed. This makes it possible to shorten the operation time and prevent the workpiece from shifting in position.

[0017] The control method of the present invention controls a first moving mechanism for moving a workpiece, a clamping mechanism for clamping the first moving mechanism, and a second moving mechanism for moving the tool or the workpiece, which is different from the first moving mechanism, and includes an axial length moving mechanism that moves in the axial length direction of the rotation axis of a tool that processes the workpiece, and determines whether the subsequent operation following the operation of the first moving mechanism is an operation of the axial length moving mechanism, and if it is an operation of the axial length moving mechanism, executes the operation of the axial length moving mechanism while the clamping operation is being performed.

[0018] In the present invention, it is determined whether the subsequent operation is an operation of the axial length moving mechanism, and if it is determined that it is an operation of the axial length moving mechanism, the operation of the axial length moving mechanism is executed after the operation of the first moving mechanism, which is unlikely to cause a shift in the position of the workpiece during the execution of the clamping operation, thereby shortening the operation time and preventing the position shift of the workpiece. [Effects of the Invention]

[0019] According to the present invention, it is possible to provide a control device and a control method that can reduce the operation time and prevent the workpiece from shifting in position. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a perspective view showing a machine tool; [Figure 2] FIG. 2 is a perspective view of the machine tool body. [Figure 3] FIG. 2 is a perspective view of the machine tool body with a portion of the machine tool body omitted. [Figure 4] FIG. 2 is a perspective view schematically showing a workpiece holding device. [Figure 5]FIG. 2 is a block diagram illustrating a schematic configuration of a main part of the machine tool. [Figure 6] 1 is a time chart showing a specific example of the operation of a machine tool. [Figure 7] 1 is a time chart showing a specific example of the operation of a machine tool. [Figure 8] 1 is a time chart showing a specific example of the operation of a machine tool. [Figure 9] 1 is a flowchart illustrating a machining operation of a machine tool. [Figure 10] 1 is a flowchart illustrating a machining operation of a machine tool. [Figure 11] FIG. 10 is an illustrative diagram showing an example of a setting screen that accepts selection of either a first instruction or a second instruction. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view showing a simplified view of machine tool 100. In the following description, up / down, left / right, and front / rear directions are indicated by arrows in the figure. The left / right direction of machine tool 100 is the X direction, the front / rear direction is the Y direction, and the up / down direction is the Z direction.

[0022] Machine tool 100 comprises a machine tool main body 1 (see FIG. 2) and a main body cover 10 that covers machine tool main body 1. Main body cover 10 has an operation panel 90 at the front that accepts instructions from a user. Machine tool 100 has a control device 7 at the rear of main body cover 10 that controls the operation of machine tool 100. FIG. 2 is a perspective view of machine tool main body 1, and FIG. 3 is a perspective view of machine tool main body 1 with a portion of machine tool main body 1 omitted.

[0023] The machine tool main body 1 includes a base 11, a spindle base 12, and a workpiece base 13. The base 11 is a generally rectangular parallelepiped that is long in the front-to-rear direction. The spindle base 12 is located at the rear upper part of the base 11, and is also a generally rectangular parallelepiped that is long in the front-to-rear direction. The dimension of the spindle base 12 in the front-to-rear direction is smaller than the dimension of the base 11 in the front-to-rear direction.

[0024] As shown in Figure 3, two support bases 12a that are long in the front-rear direction and parallel to each other are provided on the top of the spindle base 12. The support bases 12a support rails 20a, which will be described later. Two work bases 13 to which work holding devices 30 are fixed are located on the top front of the frame 11. The work holding devices 30 hold workpieces (not shown). The two work bases 13 are provided with a gap between them in the left-right direction. Each work base 13 has columnar support bases 13a and 13b that are aligned in the front-rear direction. As shown in Figure 2, the work holding devices 30 are located on top of the support bases 13a and 13b.

[0025] The machine tool 100 includes a movement mechanism (second movement mechanism) for moving a tool 25 that processes a workpiece. The movement mechanism includes an X-direction movement device 21, a Y-direction movement device 20, and a Z-direction movement device .

[0026] A Y-direction movement device 20 is located above the spindle base 12. The Y-direction movement device 20 includes a pair of parallel rails 20a, multiple blocks 20b, a Y-direction movement table 20c, a Y-axis motor 20d (see FIG. 5), and a Y-direction ball screw mechanism (not shown). The rails 20a are located above each support table 12a and extend in the front-rear direction. Each block 20b fits into the rail 20a and is movable in the front-rear direction. The Y-direction movement table 20c is located above each block 20b. The Y-direction ball screw mechanism is installed between the pair of rails 20a so that the screw shaft of the Y-direction ball screw mechanism is parallel to the rails 20a. The Y-axis motor 20d is connected to the screw shaft of the Y-direction ball screw mechanism. Hereinafter, the screw shaft of the Y-direction ball screw mechanism will also be referred to as the Y-axis. Driven by the Y-axis motor 20d, the Y-axis rotates around an axis extending in the front-rear direction. A nut for the Y-direction ball screw mechanism is attached to the bottom of the Y-direction moving table 20c. The nut for the Y-direction ball screw mechanism is connected to the Y-axis. Therefore, when driven by the Y-axis motor 20d, the Y-direction moving table 20c moves back and forth together with the block 20b.

[0027] The X-direction moving device 21 is located above the Y-direction moving table 20c. The X-direction moving device 21 includes a pair of parallel rails 21a, multiple blocks 21b, a column base 21c, an X-axis motor 21d (see FIG. 5), and an X-direction ball screw mechanism (not shown). The rails 21a are located above the Y-direction moving table 20c at an appropriate distance in the front-rear direction and extend in the left-right direction. Each block 21b fits into each rail 21a and is movable in the left-right direction. The column base 21c is located above each block 21b. The X-direction ball screw mechanism is installed between the pair of rails 21a so that the screw shaft of the X-direction ball screw mechanism is parallel to the rails 21a. The X-axis motor 21d is connected to the screw shaft of the X-direction ball screw mechanism. Hereinafter, the screw shaft of the X-direction ball screw mechanism will also be referred to as the X-axis. Driven by the X-axis motor 21d, the X-axis rotates around an axis extending in the left-right direction.

[0028] A nut of the X-direction ball screw mechanism is located below the column base 21c. The nut of the X-direction ball screw mechanism is connected to the X-axis. A column 22 extending in the vertical direction is provided above the column base 21c. Therefore, when driven by the X-axis motor 21d, the column 22 moves left and right together with the block 21b and column base 21c. When driven by the Y-axis motor 20d, the column 22 moves forward and backward together with the column base 21c, block 21b, Y-direction moving base 20c, and block 20b. The column 22 moves forward and backward and left and right by the Y-direction moving device 20 and the X-direction moving device 21.

[0029] A Z-direction moving device 23 (axial length moving mechanism) is located in front of the column 22. The Z-direction moving device 23 includes a pair of parallel rails 23a, multiple blocks 23b, a spindle head base 23c, a Z-axis motor 23d (see FIG. 5), and a Z-direction ball screw mechanism (not shown). The rails 23a are located in front of the column 22 at appropriate intervals in the left-right direction and extend vertically. Each block 23b fits into each rail 23a and is movable vertically. The spindle head base 23c is located in front of each block 23b. The Z-direction ball screw mechanism is installed between the pair of rails 23a so that the screw shaft of the Z-direction ball screw mechanism is parallel to the rails 23a. The Z-axis motor 23d is connected to the screw shaft of the Z-direction ball screw mechanism. Hereinafter, the screw shaft of the Z-direction ball screw mechanism will also be referred to as the Z-axis. Driven by the Z-axis motor 23d, the Z-axis rotates around an axis extending in the vertical direction. A nut for the Z-direction ball screw mechanism is attached to the rear of spindle head base 23c. The nut for the Z-direction ball screw mechanism is connected to the Z-axis. Therefore, when driven by Z-axis motor 23d, spindle head base 23c moves up and down together with block 23b.

[0030] The spindle head 24 is located in front of the spindle head base 23c. The spindle head 24 holds a spindle (not shown) that extends in the vertical direction so that it can rotate around an axis that extends in the vertical direction. A spindle motor 24a that is connected to the spindle is located above the spindle head 24. Drive of the spindle motor 24a causes the spindle to rotate around an axis that extends in the vertical direction. A tool 25 is attached to and detached from the lower end of the spindle. The control device 7 drives and controls the Y-axis motor 20d, X-axis motor 21d, and Z-axis motor 23d, so that the spindle head 24 (spindle and tool 25) moves in the front-to-back, left-to-right, and up-and-down directions.

[0031] 2, a workpiece holding device 30 is disposed below the spindle. The tool 25 rotates with the rotation of the spindle, and the workpiece held by the workpiece holding device 30 is machined.

[0032] 4 is a perspective view that schematically shows the work holding device 30. The work holding device 30 includes a gear box 31, a bearing box 34, a work moving mechanism 37 (first moving mechanism), a swing body 40, and a rotating table 50. The work moving mechanism 37 includes an A-axis motor 36 and a C-axis motor 60. Furthermore, the work holding device 30 includes a clamping mechanism that fixes the A-axis and C-axis. The clamping mechanism includes an A-axis clamping operation mechanism 80 and a C-axis clamping operation mechanism 81, which will be described later.

[0033] The gear box 31 houses the shaft 41 located on the right side of the oscillator 40 and supports the shaft 41 rotatably around an axis extending in the left-right direction. The shaft 41 is cylindrical. The rotation axis of the shaft 41 extends in the left-right direction. Hereinafter, the rotation axis of the shaft 41 will also be referred to as the A-axis. The A-axis motor 36 is located in the front of the gear box 31. The A-axis motor 36 is connected to a gear (not shown) provided inside the gear box 31. The A-axis motor 36 has a rotation axis extending in the front-rear direction and drives the gear. The gear is composed of, for example, a known roller gear camshaft (not shown) and a cam follower (not shown), and converts rotation of the rotation axis of the A-axis motor 36 into rotation around the A-axis. Driving the A-axis motor 36 causes the shaft 41 to rotate around the A-axis. A mounting seat 31a for fixing the gear box 31 to the right-side work base 13 is located at the bottom of the gear box 31.

[0034] The bearing box 34 houses the shaft portion 41 arranged on the left side of the oscillator 40 and rotatably supports the rotation axis (A-axis) of the shaft portion 41. A mounting seat 34a that fixes the bearing box 34 to the left-side work base 13 is located at the bottom of the bearing box 34. The shaft portion 41 of the gear box 31 and the shaft portion 41 of the bearing box 34 are located on the same axis.

[0035] The oscillator 40 includes a base plate portion 42 located between two shaft portions 41, and connecting portions 43 that connect the base plate portion 42 to each shaft portion 41. The base plate portion 42 has a flat rectangular parallelepiped shape, and both left and right edges are connected to connecting portions 43, and each connecting portion 43 connects the base plate portion 42 to the corresponding shaft portion 41.

[0036] A C-axis motor 60 is located below the base plate portion 42, and a disk-shaped rotating table 50 that holds a workpiece on its upper surface is located above the base plate portion 42. The rotation shaft of the C-axis motor 60 passes through the base plate portion 42 in the vertical direction and is connected to the rotation shaft of the rotating table 50. The rotation shaft of the C-axis motor 60 is located on the same axis as the rotation shaft of the rotating table 50. Hereinafter, the rotation shaft of the C-axis motor 60 will also be referred to as the C-axis. The C-axis is perpendicular to the A-axis. The C-axis rotates when driven by the C-axis motor 60, and the rotating table 50 rotates around the C-axis.

[0037] When the shaft 41 rotates around the A axis by driving the A-axis motor 36, the oscillating body 40 oscillates around the A axis, and the workpiece held by the turntable 50 also oscillates around the A axis together with the oscillating body 40. Furthermore, the workpiece rotates around the C axis together with the turntable 50 by driving the C-axis motor 60. As the oscillating body 40 oscillates, the C-axis direction fluctuates. In Figure 4, the axial length direction of the C axis is parallel to the up-down direction.

[0038] 5 is a block diagram showing a schematic configuration of the main parts of machine tool 100. Fig. 5 shows the connection relationship between control device 7, Z-axis motor 23d, X-axis motor 21d, Y-axis motor 20d, A-axis motor 36, and C-axis motor 60.

[0039] Machine tool 100 is equipped with an A-axis clamping mechanism 80 capable of clamping the A-axis (shaft portion 41). The A-axis clamping mechanism 80 clamps and releases the A-axis using, for example, compressed air supplied by a compressor. The A-axis clamping mechanism 80 clamps the A-axis by engaging a piston provided on a fixed portion that supports the A-axis rotation with a disk-shaped plate that rotates together with the A-axis. The piston moves between an engaged position and a disengaged position relative to the disk-shaped plate by the supply of compressed air. When the A-axis clamping mechanism 80 clamps the A-axis, the A-axis cannot rotate. Therefore, the oscillating body 40 does not oscillate. For example, during machining of a workpiece, the A-axis clamping mechanism 80 clamps the A-axis to prevent the position of the turntable 50 (workpiece) from shifting due to vibrations generated during machining.

[0040] Machine tool 100 is equipped with a C-axis clamping mechanism 81 that can fix the C-axis. C-axis clamping mechanism 81 clamps and unclamps the C-axis using compressed air supplied by a compressor, for example. C-axis clamping mechanism 81 is similar to that for the A-axis described above. When C-axis clamping mechanism 81 clamps the C-axis, the C-axis cannot rotate, and the turntable 50 does not rotate. For example, when machining a workpiece, C-axis clamping mechanism 81 clamps the C-axis to prevent the turntable 50 (workpiece) from shifting position due to vibrations generated during workpiece machining.

[0041] The control device 7 includes a CPU 70 (execution unit), a RAM 71, a non-volatile storage unit 72, and an input / output interface 73. The CPU 70, RAM 71, storage unit 72, and input / output interface 73 are communicably connected.

[0042] The memory unit 72 is, for example, an EEPROM, an EPROM, or a flash memory. The memory unit 72 may also be a hard disk. The memory unit 72 stores a control program for controlling the machine tool 100 and various information required to execute the control program. The control program includes a program for machining a workpiece. The program is an NC program. The program uses G-code or M-code. The machine tool 100 may store in the memory unit 72 a control program read from a storage medium 72a readable by the machine tool 100.

[0043] The input / output interface 73 is connected to the Y-axis motor 20d, the X-axis motor 21d, the Z-axis motor 23d, the spindle motor 24a, the A-axis motor 36, the A-axis clamp mechanism 80, the C-axis motor 60, and the C-axis clamp mechanism 81. Hereinafter, the Y-axis motor 20d, the X-axis motor 21d, the Z-axis motor 23d, the spindle motor 24a, the A-axis motor 36, and the C-axis motor 60 will also be collectively referred to as drive motors. Furthermore, the input / output interface 73 is connected to an encoder 9. An encoder 9 is provided for each drive motor. In FIG. 5, the encoders 9 for each drive motor are shown collectively. Although each drive motor is connected to each encoder 9, the connection lines between each drive motor and each encoder 9 are omitted in FIG. 5. The input / output interface 73 is connected to an operation panel 90.

[0044] CPU 70 reads out a control program stored in storage unit 72 into RAM 71 and controls various operations of machine tool 100. CPU 70 controls Y-axis motor 20d, X-axis motor 21d, Z-axis motor 23d, spindle motor 24a, A-axis motor 36, A-axis clamp mechanism 80, C-axis motor 60, and C-axis clamp mechanism 81 via input / output interface 73.

[0045] The CPU 70 acquires position information (amount of rotation) of the rotor of each drive motor from the encoder 9 via the input / output interface 73. The CPU 70 controls the drive of each drive motor based on the acquired position information. Therefore, the CPU 70 controls the drive (rotation) of the X-axis, Y-axis, Z-axis, spindle, A-axis, and C-axis. The axes related to the movement of the tool 25 (X-axis, Y-axis, and Z-axis) are also referred to as tool movement axes, the axes related to the movement of the workpiece (A-axis and C-axis) are also referred to as workpiece movement axes, and the X-axis, Y-axis, Z-axis, A-axis, and C-axis are referred to as drive axes.

[0046] When machining the workpiece, the CPU 70 controls the driving of at least one of the X-axis, Y-axis, Z-axis, spindle, A-axis, and C-axis based on a program, and moves at least one of the tool 25 and the workpiece. The movement of the workpiece includes swinging and rotating the workpiece. For example, the CPU 70 determines the drive motor of the drive axis to be controlled based on a program. Based on the program, the CPU 70 derives a target movement amount for the determined drive motor. Under the control of the CPU 70, the drive motor of the determined drive axis starts driving. For example, the CPU 70 outputs a signal indicating the start of driving to the drive motor of the determined drive axis. The drive motor of the drive axis receives the signal indicating the start of driving and starts driving. The CPU 70 derives the movement amount of the drive motor based on the position information obtained from the encoder 9. When the movement amount reaches the target movement amount, the CPU 70 outputs a signal indicating the end of driving.

[0047] Furthermore, the CPU 70 controls the clamping and release of the A-axis by the A-axis clamping mechanism 80, and the clamping and release of the C-axis by the C-axis clamping mechanism 81. To prevent the position of the turntable 50 (workpiece) from shifting, the CPU 70 controls the A-axis clamping mechanism 80 to clamp the A-axis after completing the driving of the A-axis, and controls the C-axis clamping mechanism 81 to clamp the C-axis after completing the driving of the C-axis. The following explanation will be given taking the driving of the A-axis as an example.

[0048] When the A-axis starts to drive, the CPU 70 derives a target movement amount for the A-axis motor 36. After starting to drive the A-axis, the CPU 70 periodically acquires position information of the A-axis motor 36 from the encoder 9 and derives a movement amount for the A-axis motor 36 based on the acquired position information. The CPU 70 calculates the difference between the derived movement amount and the target movement amount, and controls the A-axis motor 36 so that the calculated difference becomes zero. If the CPU 70 determines that the calculated difference is zero, it determines that the driving of the A-axis has ended. If the CPU 70 determines that the driving of the A-axis has ended, it outputs a signal to the A-axis clamp mechanism 80 instructing the A-axis clamp mechanism 80 to perform a clamping operation on the A-axis.

[0049] The operation panel 90 accepts instructions from the user. For example, the user sets whether or not a parallel instruction (non-parallel instruction), which will be described later, is possible on the operation panel 90. A parallel instruction is an instruction to execute both a clamping operation and a subsequent operation (hereinafter referred to as a "post-operation") following the operation of the workpiece moving mechanism 37 after the operation (driving the A-axis or C-axis) of the workpiece moving mechanism 37 is completed, while a non-parallel instruction is an instruction to execute the clamping operation and the post-operation separately. For example, operation panel 90 may have a display unit (not shown), and when the user turns on the power of machine tool 100, a setting screen for selecting either parallel instruction or non-parallel instruction may be displayed on the display unit.

[0050] When a parallel instruction is set on the operation panel 90, the user further sets a first instruction or a second instruction using the operation panel 90. For example, when a parallel instruction is set from the setting screen, the operation panel 90 displays a setting screen on the display unit for setting the selection of either the first instruction or the second instruction. The operation panel 90 corresponds to the setting unit. The information set on the operation panel 90 (parallel instruction, non-parallel instruction, first instruction, second instruction) is stored in the memory unit 72.

[0051] The CPU 70 makes a first determination as to whether the subsequent operation is a movement operation of the tool 25 by the Z-direction movement device 23 or a second determination as to whether the subsequent operation is a movement operation of the tool 25 by any of the movement mechanisms (tool movement axes) according to the setting on the operation panel 90. Hereinafter, the movement operation of the tool 25 by the Z-direction movement device 23 will also be simply referred to as the operation of the Z-direction movement device 23, and the movement operation of the tool 25 by the movement mechanism will also be simply referred to as the operation of the movement mechanism.

[0052] Specifically, when a first instruction is set on the operation panel 90, the CPU 70 performs a first determination. When the CPU 70 determines that the instruction is an operation of the Z-direction moving device 23, the CPU 70 executes the operation of the Z-direction moving device 23 while the clamping operation is being performed. When a second instruction is set on the operation panel 90, the CPU 70 performs a second determination. When the CPU 70 determines that the instruction is an operation of any of the movement mechanisms, the CPU 70 executes the operation of the movement mechanism during the execution of the clamp operation.

[0053] When a non-parallel instruction is set on the operation panel 90, the CPU 70 executes the post-operation after the clamping operation is completed.

[0054] The CPU 70 reads the program stored in the memory unit 72. The program that controls each drive axis for moving the workpiece or tool 25 consists of multiple blocks (or lines). The CPU 70 reads the program block by block, performs the first or second judgment for the read block, and controls the drive axis. The CPU 70 reads the block that should be executed immediately or the block that will be executed next. One block may contain multiple operations. When the block read by the CPU 70 contains multiple operations, the CPU 70 makes the above determination for each operation.

[0055] During workpiece machining, the machining time can be reduced by performing the clamping operation and the post-operation in parallel. However, if one of the drive axes is driven while the clamping operation of one drive axis is in progress and before the other drive axis is completed, the position of the drive axis, i.e., the position of the workpiece, may shift before the clamping operation is completed, resulting in a problem where the clamping operation is completed with the workpiece in a misaligned position. The machine tool 100 of this embodiment solves this problem.

[0056] 6 to 8 are time charts showing specific examples of the operation of machine tool 100. In FIGS. 6 and 7, the X-axis and Z-axis are used as tool movement axes, and the A-axis is used as a workpiece movement axis. In FIGS. 6 to 8, the horizontal axis indicates the passage of time, and the vertical axis indicates the operation state. "In-position complete" means that the workpiece or tool 25 has reached the target position, and "in-position not complete" means that the workpiece or tool 25 has not reached the target position and is still moving. "Clamped state" means that the A-axis is clamped, or the clamping operation has been completed, and "Unclamped state" means that the A-axis is not clamped, or the clamping operation has not been completed and is still being performed. If the difference between the target position of the moving axis and the position information acquired from the encoder 9 of the moving axis remains within a predetermined value (in-position width) for a predetermined period of time, the CPU 70 determines that the target position has been reached and that in-position has been completed.

[0057] A description will be given of a case where a non-parallel instruction is set on the operation panel 90. In this case, the machine tool 100 executes a post-operation after the clamping operation is completed. For example, suppose the program to be executed includes (1) A-axis movement of the workpiece and (2) X-axis and Z-axis movement of the tool 25. That is, the program to be executed includes two blocks, (1) and (2), and block (2) includes two operations, X-axis movement and Z-axis movement. 6A, the machine tool 100 does not execute any of the operations in block (2) during the clamping operation that follows after the operation in block (1) is completed. After the clamping operation is completed, the machine tool 100 starts the two operations in block (2).

[0058] A description will be given of a case where the selection of the parallel instruction and the first instruction is set on the operation panel 90. At this time, the machine tool 100 executes the operation of the Z-direction moving device 23 while executing the clamping operation. For example, suppose the program to be executed includes (1) A-axis movement of the workpiece and (2) Z-axis rapid traverse of the tool 25. That is, the program to be executed includes two blocks, (1) and (2), and each of the blocks (1) and (2) includes one operation. Here, rapid traverse is an operation that only involves movement and does not involve machining such as cutting. As shown in FIG. 6B, machine tool 100 starts and executes the operation of block (2) (rapid traverse of the Z axis) during the clamping operation that follows after the operation of block (1) is completed. When tool 25 moves in the Z axis direction, there is a relatively low possibility that the position of the workpiece (A axis and C axis) will shift. Furthermore, since this rapid traverse does not involve machining, vibrations due to machining will not occur. Therefore, machine tool 100 performs the clamping operation and rapid traverse of the Z axis in parallel, thereby shortening the operation time and preventing the position of the workpiece from shifting.

[0059] For example, suppose the program to be executed includes (1) A-axis movement of the workpiece and (2) Z-axis rapid traverse and X-axis rapid traverse of the tool 25. That is, the program to be executed includes two blocks, and block (2) includes X-axis rapid traverse in addition to Z-axis rapid traverse. 6C, machine tool 100 does not perform any of the operations in block (2) during the clamping operation after the operation in block (1) is completed. If block (2) includes X-axis rapid feed and tool 25 moves in the X-axis direction, there is a high possibility that the position of the workpiece will be shifted, so machine tool 100 starts the two operations in block (2) after the clamping operation is completed.

[0060] For example, suppose the program to be executed includes (1) A-axis movement of the workpiece, (2) Z-axis rapid feed of the tool 25, and (3) X-axis rapid feed of the tool 25. That is, the program to be executed includes three blocks, and blocks (1) to (3) each include one operation. As shown in FIG. 7D, machine tool 100 starts and executes the operation of block (2) (Z-axis rapid feed) during the clamping operation that follows after the operation of block (1) is completed (see section K), but does not execute the operation of block (3) (X-axis rapid feed). Machine tool 100 starts the operation of block (3) after the clamping operation is completed. Machine tool 100 moves tool 25 in the Z-axis direction, which is less likely to cause a shift in the position of the workpiece, in parallel with the clamping operation, and starts moving tool 25 in the X-axis direction, which is more likely to cause a shift in the position of the workpiece, after the clamping operation is completed. This achieves both a reduction in work time and prevention of workpiece position shifts.

[0061] For example, suppose the program to be executed includes (1) A-axis movement of the workpiece and (2) Z-axis movement of the tool 25. That is, the program to be executed includes two blocks, and blocks (1) and (2) each include one operation. However, the Z-axis movement of block (2) is not a rapid traverse but involves cutting. 7E, machine tool 100 does not perform the operation of block (2) during the clamping operation that follows after the operation of block (1) is completed. Although the operation of block (2) involves Z-axis movement, it also involves cutting, and therefore there is a high possibility that the position of the workpiece will be shifted due to contact between the workpiece and tool 25. Therefore, machine tool 100 starts the operation of block (2) after the clamping operation is completed.

[0062] Assume that the program to be executed includes (1) A-axis movement of the workpiece, and (2) Z-axis rapid traverse and Z-axis movement accompanied by machining of the tool 25. The program to be executed includes two or more blocks, and block (2) includes Z-axis rapid traverse and Z-axis movement accompanied by cutting machining (hereinafter referred to as Z-axis cutting movement). As shown in Figure 7F, machine tool 100 starts and executes rapid traverse of the Z axis of block (2) during the clamping operation that follows after the operation of block (1) is completed (see section K), but does not execute Z-axis cutting movement of block (2). Machine tool 100 starts Z-axis cutting movement of block (2) after completing the clamping operation. In other words, when tool 25 moves to the cutting start position on the workpiece, machine tool 100 performs this in parallel with the clamping operation, and starts Z-axis cutting movement after completing the clamping operation because there is a high possibility that deviation will occur in the position of the workpiece.

[0063] A description will be given of a case where the selection of the parallel instruction and the second instruction is set on the operation panel 90. At this time, the machine tool 100 executes the operation of one of the movement mechanisms (tool movement axes) while executing the clamping operation.

[0064] For example, suppose the program to be executed includes (1) A-axis movement of the workpiece and (2) X-axis and Z-axis rapid traverse of the tool 25. That is, the program to be executed includes two blocks, and block (2) includes both X-axis rapid traverse and Z-axis rapid traverse. As shown in Figure 8A, the machine tool 100 executes two operations of the block (2) during the clamping operation after the operation of the block (1) is completed. The machine tool 100 starts the two operations of the block (2) during the clamping operation. This reduces the work time.

[0065] For example, suppose the program to be executed includes (1) A-axis movement of the workpiece, (2) X-axis and Z-axis rapid traverse of the tool 25, and (3) X-axis rapid traverse of the tool 25. That is, the program to be executed includes three blocks, with blocks (1) and (3) each including one operation, and block (2) including X-axis rapid traverse and Z-axis rapid traverse. As shown in Figure 8B, machine tool 100 starts and executes the X-axis rapid traverse and Z-axis rapid traverse of block (2) during the clamping operation that follows after the operation of block (1) is completed, and also continues to execute the operation (X-axis rapid traverse) of block (3). Machine tool 100 starts the two operations of block (2) and the operation of block (3) during the clamping operation. This reduces the work time.

[0066] For example, suppose the program to be executed includes (1) A-axis movement of the workpiece, (2) Z-axis rapid traverse of the tool 25, and (3) X-axis movement of the tool 25. That is, the program to be executed includes three blocks, with blocks (1) and (3) each including one operation, and block (2) including both X-axis rapid traverse and Z-axis rapid traverse. However, the X-axis movement of block (3) is not rapid traverse. As shown in Figure 8C, machine tool 100 starts and executes the operation of block (2) (X-axis rapid traverse and Z-axis rapid traverse) during the clamping operation that follows after the operation of block (1) is completed (see section K), but does not execute the operation of block (3) (X-axis movement). Machine tool 100 starts the operation of block (3) after the clamping operation is completed. Because machine tool 100 starts the two operations of block (2) during the clamping operation, the work time can be shortened by section K in Figure 8C.

[0067] For example, suppose machine tool 100 executes a program relating to a general work cycle. That is, suppose the program to be executed includes (1) A-axis movement of the workpiece, and (2) X-axis rapid traverse, Z-axis rapid traverse, and Z-axis movement (Z-axis cutting movement) accompanied by machining of tool 25. The program to be executed includes two or more blocks, and block (2) includes X-axis rapid traverse, Z-axis rapid traverse, and Z-axis cutting movement. As shown in Figure 8D, machine tool 100 starts and executes X-axis rapid traverse and Z-axis rapid traverse of block (2) during the clamping operation that follows after the operation of block (1) is completed, but does not execute Z-axis cutting movement of block (2). Machine tool 100 starts Z-axis cutting movement of block (2) after the clamping operation is completed. Because machine tool 100 starts X-axis rapid traverse and X-axis rapid traverse of block (2) during the clamping operation, it can shorten the work time, and because it starts Z-axis cutting movement after the clamping operation is completed, it prevents misalignment of the workpiece.

[0068] In the above, the X-axis and Z-axis have been used as examples of tool movement axes, and the A-axis has been used as an example of workpiece movement axis, but it goes without saying that this is not limited to these, and the Y-axis as a tool movement axis and the C-axis as a workpiece movement axis can also be applied.

[0069] 9 and 10 are flow charts illustrating the machining operation of machine tool 100. For ease of explanation, the following will be described using an example in which the selection of parallel instruction and first instruction is set on operation panel 90, the operation after the operation of workpiece moving mechanism 37 is rapid traverse in the Z axis only, and the subsequent operation is Z axis cutting movement. The processing in Figures 9 and 10 is executed when the user selects a machining program using operation panel 90 and presses the start key.

[0070] For example, assume that machine tool 100 executes a machining program for a general work cycle, which is stored in memory unit 72. Processing of the flowchart begins with the execution of the machining program. The machining program includes (1) A-axis movement of the workpiece, (2) Z-axis rapid traverse and Z-axis cutting movement of the tool 25, and (3) end. The program to be executed includes two or more blocks, and block (2) includes two operations: Z-axis rapid traverse and Z-axis cutting movement.

[0071] The user turns on the power of machine tool 100 and sets parallel or non-parallel instructions on the setting screen displayed on the display unit of operation panel 90.

[0072] When parallel instructions are set, the operation panel 90 further displays a setting screen on the display unit for setting the selection of either the first instruction or the second instruction. Fig. 11 is an illustrative view showing an example of the setting screen for setting the selection of either the first instruction or the second instruction.

[0073] 11, soft buttons for accepting a first instruction or a second instruction are displayed, and the user can select "Method 1" or "Method 2" by appropriately operating the soft buttons. When the user selects Method 1, the CPU 70 stores it in the storage unit 72 as a first instruction, and when the user selects Method 2, the CPU 70 stores it in the storage unit 72 as a second instruction. On the left side of the settings screen in Figure 11, a dialog box explaining the "operation procedure" is displayed.

[0074] The CPU 70 reads the first block of the machining program and sets it as the "block currently being executed" (step S101). The first block of the machining program is block (1) relating to the A-axis movement of the workpiece.

[0075] The CPU 70 determines whether the block being executed is an end code (step S102). If the CPU 70 determines that the block being executed is an end code (step S102: YES), the processing of the machining program ends. If the CPU 70 determines that the block being executed is not an end code (step S102: NO), the CPU 70 reads the next block (step S103). That is, the CPU 70 reads block (2) related to Z-axis rapid traverse and Z-axis cutting movement and temporarily stores it in the RAM 71.

[0076] Next, the CPU 70 determines whether or not all of the operations of the block being executed, i.e., the A-axis movement of the workpiece, have been completed (step S104). Because the A-axis movement of the workpiece has not yet been completed, the CPU 70 determines that all of the operations of the block being executed have not been completed (step S104: NO), and starts the operation to be executed of the block being executed, i.e., the A-axis movement of the workpiece, as the operation being executed (step S117).

[0077] Next, the CPU 70 determines whether or not there is a next action in the block being executed (step S118). If the CPU 70 determines that there is a next action in the block being executed (step S118: YES), it sets the next action in the block being executed as the next action (step S119). If the CPU 70 determines that there is no next action in the block being executed (step S118: NO), it sets the first action in the next block stored in the RAM 71 as the next action (step S120). Since there is no next action in the currently executed block (1), the CPU 70 sets the first action (Z-axis fast forward) in the next block (2) as the next action.

[0078] The CPU 70 determines whether or not all axes have been in position based on the position information from the encoder 9 (step S108). If the CPU 70 determines that all axes have not been in position (step S108: NO), it continues the operation currently being executed (step S113).If the CPU 70 determines that all axes have been in position (step S108: YES), it determines whether the axes related to the operation (movement) of the block currently being executed are equipped with clamp mechanisms (step S109).

[0079] Since the operation of the currently executing block (1) is the A-axis movement of the workpiece and the A-axis has the A-axis clamping mechanism 80, the CPU 70 determines that the axis related to the operation (movement) of the currently executing block is equipped with a clamping mechanism (step S109: YES) and starts clamping the A-axis (step S110).On the other hand, if the CPU 70 determines that the axis related to the operation (movement) of the currently executing block is not equipped with a clamping mechanism (step S109: NO), the process proceeds to step S104.

[0080] After clamping of the A-axis is started, the CPU 70 determines whether the instruction set on the setting screen of the operation panel 90 is Method 2 (second instruction) based on the contents stored in the memory unit 72 (step S111). If the CPU 70 determines that the set instruction is Method 2 (step S111: YES), the process proceeds to step S112. In this embodiment, the case where a first instruction is received is taken as an example. The CPU 70 determines that the received instruction is not Method 2, i.e., Method 1 (step S111: NO), and determines whether the subsequent operation is the operation of the Z-direction moving device 23 (step S114). That is, in the case of the first instruction, the CPU 70 determines whether the subsequent operation is the operation of the Z-direction moving device 23. Since the current subsequent operation is Z-axis fast-forward, the CPU 70 determines that the subsequent operation is the operation of the Z-direction moving device 23 (step S114: YES), and the process proceeds to step S112. In S111, the CPU 70 determines that the method is not Method 2 but that the method is Method 1. However, if NO in S111, a separate step may be provided to determine whether the method is Method 1 or not.

[0081] If the CPU 70 determines that the post-operation is not an operation of the Z-direction moving device 23 (step S114: NO), the CPU 70 determines whether the clamping operation has been completed (step S115). If the CPU 70 determines that the clamping operation has not been completed (step S115: NO), the clamping operation continues (step S116). If the CPU 70 determines that the clamping operation has been completed (step S115: YES), the process proceeds to step S104. Whether the clamping operation has been completed may be determined by the passage of a predetermined time from the start of clamping, or may be determined using a sensor that detects the operating position of the clamping mechanism.

[0082] In step S112, the CPU 70 determines whether the subsequent action is a fast-forward action (step S112). If the CPU 70 determines that the subsequent action is not a fast-forward action (step S112: NO), the process proceeds to step S115. If the CPU 70 determines that the subsequent action is a fast-forward action (step S112: YES), the process returns to step S104.

[0083] The CPU 70 again determines whether all operations of the block being executed have been completed (step S104). The operation of the block (1) being executed is only the A-axis movement of the workpiece, and has already been completed in step S108. Therefore, the CPU 70 determines that all operations of the block being executed have been completed (step S104: YES), and sets the next block as the block being executed (step S105). That is, the CPU 70 sets block (2) as the block being executed.

[0084] The CPU 70 also determines whether the currently executing block is an end code (step S106). If the CPU 70 determines that the currently executing block is an end code (step S106: YES), the processing of the machining program ends. If the CPU 70 determines that the currently executing block is not an end code (step S106: NO), the CPU 70 reads the next block (step S107). That is, the CPU 70 reads block (3) related to the end and temporarily stores it in the RAM 71. Thereafter, the processing returns to step S104.

[0085] The CPU 70 determines whether all operations of the currently executing block have been completed (step S104). Since neither the Z-axis rapid feed nor the Z-axis cutting movement of the tool 25 of the currently executing block (2) have been completed yet, the CPU 70 determines that all operations of the currently executing block have not been completed (step S104: NO), and sets the operation to be executed (Z-axis rapid feed of the tool 25) of the currently executing block as the currently executing operation and starts its execution (step S117). That is, the CPU 70 executes the Z-axis rapid feed of the tool 25, which is the subsequent operation, during the execution of the A-axis clamping operation.

[0086] In the following step S118, the CPU 70 determines that the block being executed has a next operation (step S118: YES), sets the next operation (Z-axis cutting movement) of the block being executed as the subsequent operation (step S119), and the process proceeds to step S108.

[0087] In step S108, the CPU 70 determines whether or not all axes have been in position (step S108), and if it is determined that all axes have been in position (step S108: YES), it determines whether or not the instruction set on the setting screen is method 2 (second instruction) (step S111). In this embodiment, the first instruction is set, and the CPU 70 determines that the set instruction is not method 2 (step S111: NO), and the process proceeds to step S114.

[0088] Since the current post-operation is a Z-axis cutting movement, in step S114, the CPU 70 determines that the post-operation is an operation of the Z-direction movement device 23 (step S114: YES), and the process proceeds to step S112. In step S112, the CPU 70 determines that the post-operation (Z-axis cutting movement) is not a fast-forward operation (step S112: NO), and the process proceeds to step S115. In step S115, the CPU 70 determines whether the clamping operation has been completed (step S115). If the CPU 70 determines that the clamping operation has been completed (step S115: YES), the process proceeds to step S104.

[0089] The CPU 70 again determines whether or not all operations of the currently executing block, i.e., block (2), have been completed (step S104). If the CPU 70 determines that all operations of the currently executing block (2) have been completed (step S104: YES), it sets the next block, i.e., block (3), as the currently executing block (step S105). The CPU 70 then determines whether or not the currently executing block is an end code (step S106). Since block (3) has ended, the CPU 70 determines that the currently executing block is an end code (step S106: YES), and processing of the machining program ends. The CPU 70 that executes S114 corresponds to the determination unit. The CPU 70 that executes S114 (YES), S112 (YES), S104 (YES), S105, and S117 corresponds to the execution unit. The CPU 70 that executes S111 corresponds to the instruction determination unit. The CPU 70 that executes S103 and S107 corresponds to the reading unit.

[0090] In the above, an example has been described in which machine tool 100 has A-axis motor 36 and C-axis motor 60 as workpiece moving mechanism 37, and A-axis clamp mechanism 80 and C-axis clamp mechanism 81 as clamp mechanisms, but this is not limiting. Workpiece moving mechanism 37 may also have a B-axis motor, and a B-axis clamp mechanism as a clamp mechanism. Here, the B-axis is the axis of workpiece movement that is perpendicular to the A-axis and C-axis. [Explanation of symbols]

[0091] 7 Control Device 20 Y direction movement device (second movement mechanism) 21 X direction movement device (second movement mechanism) 23 Z direction movement device (second movement mechanism, axis length movement mechanism) 25 Tools 37 Work moving mechanism (first moving mechanism) 70 CPU (execution unit, judgment unit, instruction judgment unit, reading unit) 80 A-axis clamp mechanism 81 C-axis clamping mechanism 90 Operation panel (setting section) 100 Machine tools

Claims

1. A control device that controls a first moving mechanism for moving a workpiece, a clamping mechanism that clamps the first moving mechanism, and a second moving mechanism for moving a tool that processes the workpiece or a workpiece different from the first moving mechanism, the second movement mechanism includes an axial length movement mechanism that moves in an axial length direction of the rotation shaft of the tool, a determination unit that determines whether a subsequent operation following the operation of the first moving mechanism is an operation of the axial length moving mechanism; a setting unit that sets a first instruction or a second instruction; an instruction determination unit that determines whether the setting unit has set the first instruction or the second instruction, an execution unit that starts execution of the operation of the axial length movement mechanism during execution of a clamping operation that performs the clamping when the instruction determination unit determines that the instruction set by the setting unit is the first instruction and the determination unit determines that the post-operation is an operation of the axial length movement mechanism; the execution unit starts execution of the operation of the second moving mechanism other than the axial length moving mechanism after the clamping operation is completed when the instruction determination unit determines that the instruction set by the setting unit is the first instruction and the determination unit determines that the post-operation is an operation of the second moving mechanism other than the axial length moving mechanism; The execution unit is a control device that starts executing the operation of one of the second moving mechanisms during the execution of the clamping operation when the instruction determination unit determines that the instruction set by the setting unit is the second instruction.

2. The control device according to claim 1 , wherein the operation of the axial length movement mechanism and the operation of any one of the second movement mechanisms are movements that do not involve machining.

3. a reading unit that reads each block from a plurality of blocks including one or a plurality of operations; The control device according to claim 1 or 2, wherein the determining unit performs the determination for each operation on the block read by the reading unit.

4. The execution unit: During the execution of the clamping operation, the second moving mechanism is operated to move the tool to a machining start position on the workpiece; The control device according to claim 1 , wherein, after the clamping operation is completed, an operation of the second movement mechanism is executed to move the tool while machining the workpiece.

5. A control method for controlling a first movement mechanism for moving a workpiece, a clamping mechanism for clamping the first movement mechanism, and a second movement mechanism for moving the workpiece, which is different from the tool or the first movement mechanism, including an axial length movement mechanism for moving the tool in an axial length direction of a rotation axis of a tool that processes the workpiece, determining whether a setting unit that sets a first instruction or a second instruction has set the first instruction or the second instruction; When it is determined that the instruction set by the setting unit is the first instruction and that the subsequent operation following the operation of the first moving mechanism is the operation of the axial length moving mechanism, execution of the operation of the axial length moving mechanism is started during execution of a clamping operation for performing the clamping; When it is determined that the instruction set by the setting unit is the first instruction and that the subsequent operation is an operation of the second moving mechanism other than the axial length moving mechanism, execution of the operation of the second moving mechanism other than the axial length moving mechanism is started after the clamping operation is completed; A control method for starting the execution of an operation of any of the second moving mechanisms during the execution of the clamping operation when it is determined that the instruction set by the setting unit is the second instruction.

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