WO2023079589A1 - Dispositif de commande et support d'enregistrement lisible par ordinateur - Google Patents

Dispositif de commande et support d'enregistrement lisible par ordinateur Download PDF

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Publication number
WO2023079589A1
WO2023079589A1 PCT/JP2021/040365 JP2021040365W WO2023079589A1 WO 2023079589 A1 WO2023079589 A1 WO 2023079589A1 JP 2021040365 W JP2021040365 W JP 2021040365W WO 2023079589 A1 WO2023079589 A1 WO 2023079589A1
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WO
WIPO (PCT)
Prior art keywords
machining
unit
control device
induction motor
control
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Application number
PCT/JP2021/040365
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English (en)
Japanese (ja)
Inventor
宏祐 宇野
Original Assignee
ファナック株式会社
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Publication date
Application filed by ファナック株式会社 filed Critical ファナック株式会社
Priority to PCT/JP2021/040365 priority Critical patent/WO2023079589A1/fr
Publication of WO2023079589A1 publication Critical patent/WO2023079589A1/fr

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    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
    • G05B19/404—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia

Definitions

  • the present invention relates to control devices and computer-readable recording media.
  • An induction motor generates magnetic flux by passing an exciting current. Increasing the magnetic flux of the induction motor increases the torque. On the other hand, power consumption increases and the motor generates heat (Patent Document 1, etc.). Therefore, when there is no load, the exciting current of the induction motor is suppressed to a value lower than the rated value to reduce heat generation.
  • the control device solves the above problems by predicting the machining details ahead of the magnetic flux delay time from the analysis result of the machining program and controlling the magnetic flux amount.
  • one aspect of the present disclosure is a control device that controls a machine including a drive unit driven by an induction motor, comprising: an analysis unit that analyzes a machining program that includes commands for controlling the machine; a control command unit that commands the rotation of the induction motor based on the result; and a machining content prediction unit that predicts the machining content after a predetermined control switching time based on the analysis result of the machining program.
  • the control command unit is a control device that controls the amount of magnetic flux of the induction motor based on the machining content predicted by the machining content prediction unit.
  • Another aspect of the present disclosure is a computer-readable recording medium recording a program for operating a control device that controls a machine having a drive unit driven by an induction motor, the machining program including instructions for controlling the machine.
  • a control command unit that commands the rotation of the induction motor based on the analysis result of the analysis unit; and predicts the machining content after a predetermined control switching time based on the analysis result of the machining program.
  • the computer is readable by recording a program for controlling the amount of magnetic flux of the induction motor based on the machining content predicted by the machining content prediction unit.
  • the heat generation of the induction motor can be suppressed by lowering the exciting current in the positioning feed portion.
  • the excitation current is increased before machining to increase the amount of magnetic flux, it can be expected that there will be no effects such as a decrease in spindle speed or stoppage.
  • FIG. 1 is a schematic hardware configuration diagram of a control device according to an embodiment of the present invention
  • FIG. 3 is a block diagram showing schematic functions of a control device according to the first embodiment of the present invention
  • FIG. It is a figure which shows the example of a processing program.
  • 7 is a graph illustrating the result of analyzing the machining program; It is a figure which shows the example of prediction by a process content prediction part. It is a figure which shows the other example of the prediction by a process content prediction part.
  • FIG. 6 is a block diagram showing the schematic functions of a control device according to a second embodiment of the present invention; It is a figure which shows the example of the prediction by the content prediction part of machining based on a simulation result.
  • FIG. 10 is a diagram showing another example of prediction by the machining content prediction unit based on simulation results;
  • FIG. 11 is a block diagram showing schematic functions of a control device according to a modification of the second embodiment;
  • FIG. 1 is a schematic hardware configuration diagram showing essential parts of a control device according to an embodiment of the present invention.
  • the control device 1 of the present invention can be implemented as a control device for controlling a machine tool having a drive section driven by an induction motor.
  • a control device 1 that controls a machine tool that processes a work by controlling the relative positions of the tool and the work will be described below as an example.
  • the CPU 11 included in the control device 1 of the present invention is a processor that controls the control device 1 as a whole.
  • the CPU 11 reads a system program stored in the ROM 12 via the bus 22 and controls the entire control device 1 according to the system program.
  • the RAM 13 temporarily stores calculation data, display data, various data input from the outside, and the like.
  • the non-volatile memory 14 is composed of, for example, a memory backed up by a battery (not shown) or an SSD (Solid State Drive), and retains the stored state even when the control device 1 is powered off.
  • the nonvolatile memory 14 stores data and machining programs read from the external device 72 via the interface 15, data and machining programs input via the input device 71, various data obtained from the machine tool 3, and the like. be done.
  • the data and processing programs stored in the nonvolatile memory 14 may be developed in the RAM 13 at the time of execution/use.
  • various system programs such as a known analysis program are pre-written in the ROM 12 .
  • the interface 15 is an interface for connecting the CPU 11 of the control device 1 and an external device 72 such as a USB device. From the external device 72 side, it is possible to read, for example, a machining program and various parameters used for controlling the machine tool 3 . Moreover, the machining program and each parameter edited in the control device 1 can be stored in the external storage means via the external device 72 .
  • a PLC (programmable logic controller) 16 controls the machine tool 3 and peripheral devices of the machine tool 3 (for example, a tool changer, an actuator such as a robot, a machine tool 3 A sensor or the like attached to the controller) is controlled by outputting a signal through the I/O unit 17 . Also, the PLC 16 receives signals from various switches on an operation panel provided in the main body of the industrial machine, peripheral devices, etc., performs necessary signal processing, and then transfers the signals to the CPU 11 .
  • each data read into the memory data obtained as a result of executing the machining program, the system program, etc., are output via the interface 18 and displayed.
  • An input device 71 composed of a keyboard, a pointing device, and the like passes commands, data, and the like based on operations by the operator to the CPU 11 via the interface 19 .
  • An axis control circuit 30 for controlling the axes provided in the machine tool 3 receives an axis movement command amount from the CPU 11 and outputs an axis command to the servo amplifier 40 .
  • the servo amplifier 40 receives this command, and drives the servo motor 50 that moves the drive section of the machine tool 3 along the axis.
  • the axis servo motor 50 incorporates a position/velocity detector, and feeds back a position/velocity feedback signal from this position/velocity detector to the axis control circuit 30 .
  • the axis control circuit 30 performs feedback control of the position and speed of the servomotor 50 .
  • axis control circuit 30, one servo amplifier 40, and one servomotor 50 are shown in the hardware configuration diagram of FIG. Only a few are provided.
  • the spindle on which the tool is attached and the workpiece are relatively moved in the directions of the three linear axes (X-axis, Y-axis, Z-axis).
  • Three sets of axis control circuit 30, servo amplifier 40, and servo motor 50 are prepared.
  • a spindle control circuit 60 receives a spindle rotation command and outputs a spindle speed signal to a spindle amplifier 61 .
  • the spindle amplifier 61 receives this spindle speed signal, rotates the induction motor 62 of the machine tool 3 at the commanded rotational speed, and drives the spindle.
  • a position coder 63 is coupled to the induction motor 62 .
  • the position coder 63 outputs feedback pulses in synchronization with the rotation of the main shaft, and the feedback pulses are read by the CPU 11 .
  • the spindle control circuit 60 controls the amount of magnetic flux of the induction motor 62 with respect to the spindle amplifier 61 .
  • the spindle amplifier 61 obtains the current amount of magnetic flux of the induction motor 62 and transfers it to the CPU 11 .
  • FIG. 2 is a schematic block diagram showing the functions of the control device 1 according to the first embodiment of the present invention.
  • the control device 1 according to the present embodiment controls the relative positions of the rotating tool and the workpiece, and cuts the workpiece by bringing the tool and the workpiece into contact with each other.
  • Each function provided in the control device 1 according to the present embodiment is realized by the CPU 11 provided in the control device 1 shown in FIG.
  • the control device 1 of this embodiment includes an analysis unit 100, a position command unit 110, a machining content prediction unit 130, and a control command unit 140.
  • a machining program 200 used for controlling the machine tool 3 is stored in advance, and a time required for switching the control of the induction motor 62 is stored.
  • a control switching time storage unit 210 is secured as an area.
  • the analysis unit 100 sequentially reads the blocks of the machining program 200. Then, the instruction by the read block is analyzed.
  • the analysis result includes a command to change the position of the tool
  • the analysis unit 100 commands the position command unit 110 to control the position of each servomotor 50 .
  • the control command unit 140 is commanded to control the rotation of the induction motor 62 .
  • the analysis unit 100 outputs at least the type of the analyzed command (whether it is a positioning command or a cutting feed command) and the time required for feed control according to each command to the machining content prediction unit 130 . It is desirable that the analysis unit 100 prefetches and analyzes blocks of the machining program 200 .
  • the position command unit 110 Based on the analysis result of the machining program 200 by the analysis unit 100, the position command unit 110 outputs to the machine tool 3 a command to drive the servo motor 50 so as to control the position of the tool with respect to the work.
  • the machining content prediction unit 130 predicts the content of machining to be performed after the current time (the current elapsed time from the start of machining).
  • the control switching time storage unit 210 stores in advance the control switching time, which is the time it takes for the magnetic flux to stabilize after the excitation current is changed in the induction motor 62 attached to the machine tool 3 . This control switching time may be obtained in advance by conducting an experiment using the induction motor 62 .
  • the machining content prediction unit 130 predicts the content of machining after at least the control switching time from the current time.
  • the machining content prediction unit 130 predicts that the workpiece is not being machined by the tool while the control based on the positioning command is being performed, for example. Also, while the control based on the cutting feed command is being performed, it is predicted that the workpiece is being machined by the tool.
  • FIG. 3 shows an example of the machining program 200.
  • FIG. 4 shows the analysis result of the machining program 200 illustrated in FIG. 3 by the analysis unit 100 as a graph.
  • a positioning command G00 is issued in block N05.
  • a cutting feed command G01 is issued at N06.
  • the analysis unit 100 calculates the time required to execute each command based on the feed speed of each feed command.
  • FIG. 3 shows an example of the machining program 200.
  • FIG. 4 shows the analysis result of the machining program 200 illustrated in FIG. 3 by the analysis unit 100 as a graph.
  • a positioning command G00 is issued in block N05.
  • a cutting feed command G01 is issued at N06.
  • the analysis unit 100 calculates the time required to execute each command based on the feed speed of each feed command.
  • the positioning command of block N05 is executed from the time of starting machining to the time of elapsed time t1
  • the positioning command of block N06 is executed from the time of elapsed time t1 to the time of elapsed time t2.
  • a cutting feed command is executed.
  • the analysis unit 100 outputs the result of this analysis to the processing content prediction unit 130 . Note that the analysis unit 100 may calculate the execution time of each command in consideration of the acceleration/deceleration of each axis more strictly.
  • FIG. 5 and 6 are graphs explaining the prediction of the processing content by the processing content prediction unit 130.
  • the current time is indicated by tc
  • the control switching time is indicated by td.
  • the machining content prediction unit 130 predicts the machining content after the control switching time td from the current time tc at predetermined intervals. For example, as shown in FIG. 5, consider the case where the time obtained by adding the control switching time td to the current time tc is before the elapsed time t1. At this time, the machining content prediction unit 130 determines that the positioning command of block N05 has been executed after the control switching time td from the current time tc. Then, based on this determination result, the machining content prediction unit 130 predicts that the workpiece will not be machined after the control switching time td.
  • the machining content prediction unit 130 determines that the cutting feed command of block N06 is being executed after the control switching time td from the current time tc. Based on this determination result, the machining content prediction unit 130 predicts that the workpiece will be machined after the control switching time td.
  • the control command unit 140 outputs a command to the machine tool 3 to rotate the induction motor 62 at the commanded rotational speed based on the analysis result of the machining program 200 by the analysis unit 100 .
  • the control command unit 140 controls the amount of magnetic flux of the induction motor 62 based on the prediction result of the machining content by the machining content prediction unit 130 .
  • a method of controlling the amount of magnetic flux for example, a method of controlling an exciting current flowing through an induction motor is conceivable.
  • the control command unit 140 sets the excitation current to a predetermined value lower than the rated value when it is predicted that the tool will not machine the workpiece from the current time tc until after the control switching time td. Control.
  • the exciting current is controlled to, for example, the rated value so as to obtain a sufficient amount of magnetic flux necessary for machining.
  • the control device having the above configuration, there is no problem even if the amount of magnetic flux is reduced in the positioning feed portion, so heat generation of the induction motor can be suppressed by reducing the excitation current.
  • the excitation current of the induction motor is increased so as to obtain a sufficient amount of magnetic flux necessary for machining the workpiece in the cutting feed portion, it can be expected that there will be no effects such as a decrease in spindle speed or stoppage. Since not only the control to increase the exciting current but also the control to decrease the exciting current can be performed based on the prediction considering the control switching time, it is expected that the electric power can be used efficiently.
  • FIG. 7 is a schematic block diagram of the functions provided by the control device 1 according to the second embodiment of the present invention.
  • the control device 1 according to the present embodiment controls the relative positions of the rotating tool and the workpiece, and cuts the workpiece by bringing the tool and the workpiece into contact with each other.
  • Each function provided in the control device 1 according to the present embodiment is realized by the CPU 11 provided in the control device 1 shown in FIG.
  • the control device 1 of this embodiment includes an analysis unit 100, a position command unit 110, a simulation unit 120, a machining content prediction unit 130, and a control command unit 140.
  • a machining program 200 used for controlling the machine tool 3 is stored in advance, and a time required for switching the control of the induction motor 62 is stored.
  • a control switching time storage unit 210 is secured as an area.
  • the position command unit 110 and the control command unit 140 according to this embodiment have the same functions as the position command unit 110 and the control command unit 140 according to the first embodiment.
  • the analysis unit 100 analyzes the machining program 200 and outputs control commands to the position command unit 110 and the control command unit 140, like the analysis unit 100 according to the first embodiment.
  • the analysis unit 100 according to this embodiment does not necessarily have to sequentially output the analysis results to the machining content prediction unit 130 . At least at the timing when the machining is started, the machining content prediction unit 130 is notified of the fact.
  • the simulation unit 120 sequentially reads the blocks of the machining program 200. Then, a machining simulation is executed based on the command from the read block.
  • the simulation processing by the simulation unit 120 is desirably a machining simulation using at least commands from the blocks of the machining program 200, the arrangement of the tool and the workpiece, and the shapes of the tool and the workpiece. Moreover, it is desirable that the machining simulation be able to perform a strict analysis of the time required for the machining with the tool and the workpiece in contact with each other. Since such machining simulation is already known, detailed description thereof is omitted in this specification.
  • the simulation unit 120 only needs to execute machining simulation of the block before the command of each block of the machining program 200 is executed.
  • all the machining simulations of the machining program 200 may be completed in advance, or the machining simulations may be executed in parallel (and prior to) the workpiece machining based on the machining program 200 .
  • the simulation unit 120 outputs to the machining content prediction unit 130 the results of the machining simulation including at least the time during which the tool is in contact with the workpiece and machining is being performed.
  • the machining content prediction unit 130 predicts the content of machining at a predetermined time during machining of the workpiece based on the result of machining simulation of the machining program 200 by the simulation unit 120 .
  • the control switching time storage unit 210 pre-stores the control switching time similarly to the first embodiment.
  • FIGS. 8 and 9 explain the prediction of machining details by the machining details prediction unit 130 based on the results of the machining simulation.
  • the machining content prediction unit 130 predicts the machining content after the control switching time from the current time based on the result of the machining simulation at predetermined intervals. For example, as shown in FIG. 8, consider the case where the tool 301 is not in contact with the workpiece 303 on the machining simulation after the control switching time from the current time after the machining is started. At this time, the machining content prediction unit 130 determines that the tool 301 and the workpiece 303 are not in contact with each other even in the actual machining after the control switching time from the current time. Based on this determination result, the machining content prediction unit 130 predicts that the workpiece 303 will not be machined after the control switching time.
  • the machining content prediction unit 130 determines that the tool 301 and the workpiece 303 are in contact with each other even in the actual machining after the control switching time from the current time. Based on this determination result, the machining content prediction unit 130 predicts that the workpiece 303 will be machined after the control switching time.
  • the control device having the above configuration, there is no problem even if the amount of magnetic flux is reduced in the positioning feed portion, so heat generation of the induction motor can be suppressed by reducing the excitation current.
  • the excitation current is increased so as to obtain a sufficient amount of magnetic flux necessary for machining the work in the cutting feed portion, it can be expected that the influence of the spindle speed reduction and stoppage will be eliminated.
  • a machining program creator provides a predetermined margin before and after the contact range between the workpiece and the tool. That is, the path of the cutting feed command is longer than the range in which the work is actually machined. Also, there are cases where a cutting feed command is used in a portion that should be axially fed by a positioning command.
  • the excitation current is controlled based on the contents of the command as in the control device according to the first embodiment, power consumption may be wasted. Since the control device according to the present embodiment strictly determines the contact range between the tool and the workpiece based on the results of the machining simulation, the excitation current is controlled more precisely than the control device according to the first embodiment. It is possible to do
  • FIG. 10 shows a modification of the control device 1 according to the second embodiment.
  • the control device 1 according to the second embodiment has a simulation section 120 .
  • the simulation section may be configured on a PC installed alongside the control device 1, or a fog computer or host computer connected via a network (not shown).
  • the control device 1 prepares a simulation result storage section 220, which is an area for storing simulation results by the external simulation device 2, on the RAM 13 to nonvolatile memory 14.
  • the machining simulation of the machining program 200 is executed by the simulation unit 240 provided in the simulation device 2 in advance or in parallel and precedingly.
  • the results of the machining simulation are stored in the simulation result storage unit 220 .
  • the machining content prediction unit 130 may refer to the simulation result storage unit 220 and predict the machining content after the control switching time from the current time.
  • Such a configuration eliminates the need to perform simulation processing on the control device 1 .
  • the functions of the present invention can be utilized even if the control device is not a high-performance control device that can perform machining simulation in parallel with the control of the machine tool.
  • the present invention is not limited to the above-described examples of the embodiments, and can be implemented in various modes by adding appropriate modifications.
  • a machine tool is described as an example of a control target by the control device.
  • any machine that utilizes an induction motor to drive the drive may utilize the features of the present invention.
  • the control command unit 140 controls the amount of magnetic flux of the induction motor according to the amount of cutting. As a result, it is possible to appropriately control the amount of magnetic flux according to the load on the spindle due to the details of machining.
  • control device 2 simulation device 3 machine tool 11 CPU 12 ROMs 13 RAM 14 nonvolatile memory 15, 18, 19 interface 16 PLC 17 I/O unit 22 bus 70 display device 71 input device 72 external device 100 analysis unit 110 position command unit 120 simulation unit 130 machining content prediction unit 140 control command unit 200 machining program 210 control switching time storage unit 220 simulation result storage unit 240 Simulation part 301 Tool 303 Work

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  • Human Computer Interaction (AREA)
  • Manufacturing & Machinery (AREA)
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  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Numerical Control (AREA)

Abstract

Un dispositif de commande selon la présente invention est destiné à commander une machine pourvue d'une unité d'entraînement qui est entraînée par un moteur à induction. Le dispositif de commande comprend : une unité d'analyse servant à analyser un programme de traitement dans lequel une commande pour commander la machine est incluse ; une unité de commande de commande servant à commander la rotation d'un moteur à induction sur la base d'un résultat d'analyse par l'unité d'analyse ; et une unité de prédiction de détail de traitement servant à prédire, sur la base du résultat d'analyse par le programme de traitement, un détail de traitement à utiliser avant un temps de commutation de commande prédéterminé. L'unité de commande de commande commande la quantité de flux magnétique du moteur à induction sur la base du détail de traitement prédit par l'unité de prédiction de détail de traitement.
PCT/JP2021/040365 2021-11-02 2021-11-02 Dispositif de commande et support d'enregistrement lisible par ordinateur WO2023079589A1 (fr)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2019075961A (ja) * 2017-10-19 2019-05-16 ファナック株式会社 モータ制御装置
JP2021081848A (ja) * 2019-11-15 2021-05-27 ファナック株式会社 制御装置、及び制御システム
WO2021193496A1 (fr) * 2020-03-25 2021-09-30 ファナック株式会社 Dispositif de commande

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2019075961A (ja) * 2017-10-19 2019-05-16 ファナック株式会社 モータ制御装置
JP2021081848A (ja) * 2019-11-15 2021-05-27 ファナック株式会社 制御装置、及び制御システム
WO2021193496A1 (fr) * 2020-03-25 2021-09-30 ファナック株式会社 Dispositif de commande

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