JP4385404B2 - Motor drive device and method for emergency stop of motor drive device - Google Patents

Description

  The present invention relates to a motor drive device that controls a multi-axis multi-axis machine and an emergency stop method for the motor drive device.

Two conventional methods for emergency stop of a motor drive device have been proposed. One is an emergency stop method for a motor drive device that controls a multi-axis machine having two axes mechanically coupled (see, for example, Patent Document 1). The emergency stop method will be described with reference to FIGS. FIG. 8 shows a configuration of a crankpin grinding device which is a synchronous drive device of a machine tool. In FIG. 8, the left machine block is the left chuck drive device, and the right machine block is the right chuck drive device. 36R and 36L are spindle motors, 38R and 38L are gears, 40R and 40L are encoders, 42R and 42L are electromagnetic brakes, 48R and 48L are servo amplifiers, 54 is a CNC device, 56 is a PLC device, and 58R and 58L are dynamic brake mechanisms. It is. The two hydraulic chucks 22R and 22L on both sides to which the workpiece is fixed are realized by synchronously driving two spindle motors 36R and 36L. Accordingly, when the synchronization is lost, a twist occurs between the two hydraulic chucks, stress is applied to the workpiece, and in some cases, the workpiece may be damaged. For this reason, the conventional example is devised so as to reduce the synchronization shift even in the event of an emergency such as a power failure or failure. That is, when an operation abnormality occurs, first, the two spindle motors 36R and 36L are decelerated by operating the dynamic brakes 58R and 58L for a certain period of time determined by a timer, and then the electromagnetic brakes 42R and 42L are operated and stopped. Yes.
The second is a servo control configuration in which serial communication is performed between the computer and a plurality of servo controllers that perform motion control of the motor. (For example, refer to Patent Document 2). In FIG. 10, 101 is a personal computer, 102 is a personal computer expansion board, a high-speed serial communication interface, and 103 to 105 are servo controllers. The computer 101 and the servo controllers 103 to 104 are connected by two transmission means of a first transmission 106 and a second transmission 107. That is, the first transmission 106 transmits information from the computer 101 to the servo controllers 103 to 105, and the second transmission 107 transmits information from the servo controllers 103 to 105 to the computer. In this conventional example, alarm information generated by the servo controllers 103 to 105 is written to the memory of the computer 101 through the second transmission 107, and the computer 101 performs processing according to the alarm information and performs the first transmission 106. The position information of the servo controller that generated the command or alarm is transmitted to each servo controller 103-105. The servo controllers 103 to 105 perform processing in accordance with commands from the computer 101.
Japanese Patent Laid-Open No. 11-300565 (No. 4-6, FIGS. 2 and 4) Japanese Patent Laid-Open No. 10-326107 (No. 8-9, FIG. 1)

However, in the emergency stop method of the synchronous drive device of the machine tool, it is not possible to avoid deviation due to variations in the spindle motor, load, etc. of the constituting hardware, and it is not possible to increase the synchronization accuracy of the two axes any more. There was a problem.
In servo control that performs serial communication, position information is returned to the computer by the second transmission when an alarm occurs, and after processing by the computer, commands and position information of the alarm generating servo controller are sent to the servo controller via the first transmission. Since the data is transmitted to each servo controller, there is a problem that a time delay occurs and a delay occurs in the follow-up operation when an emergency stop is performed.
The present invention has been made in view of such problems. The controller and the drive device are connected by the first transmission means and the position detector is connected by the second transmission means, and the position deviation between the axes is monitored. An abnormality is detected at a certain deviation or more, and the drive device that has detected the abnormality is stopped by a predetermined method based on the position information of the drive device that has generated the abnormality.
Thus, an object of the present invention is to provide an emergency stop method for a motor drive device that can improve the synchronization accuracy between axes and reduce the stress of a machine even if variations such as a load occur.

In order to solve the above problem, the present invention is as follows.
The invention according to claim 1 is a multi-axis drive device that drives a two-axis machine coupled by a fastening portion and a multi-axis machine interlocked with the two-axis machine. A first motor for driving, a first driving device, a second motor for driving the other of the two-axis machine, a second driving device, and a third motor to an n-th motor for driving other than the two-axis machine; a n-th driving device from the third driving device consists of a controller for controlling to said n-th driving unit from the first drive unit via a first transmission means for each sampling time, the first or the second In an emergency stop method when an abnormality occurs in any one of the two drive devices, the drive device transmits the position information obtained from the position detector between the first to n-th drive devices (2) to (5). using a second transmission means for interconnecting, Serial first or between the second driving unit (2), (3) to monitor each other between the axes deviation, the abnormality detection in the case where the inter-first or the second axis deviation exceeds the set threshold value is, the second through the transmission means (20) the first or second drive unit (2), (3) abnormal driving device of a n from the third detected in the first or the previous SL 2 Based on the position of the driving device, the procedure follows the position of the first or second driving device (2), (3) where the abnormality is detected, and stops so that the deviation between the axes becomes small. An emergency stop method, or when there is distortion between the axes, the position of the first or second driving device (2) or (3) where the abnormality is detected while keeping the distortion is followed, and the deviation between the axes. Emergency stop by the procedure of stopping so as to decrease, or the first in which an abnormality is detected Or, when following the position of the second drive device (2), (3) and stopping so that the deviation between the axes becomes small, the control gain is lowered to make an emergency stop so that no interference occurs between the axes. An emergency stop is made by any of the methods .
The invention according to claim 2 is a multi-axis drive device that drives a two-axis machine coupled by a fastening portion and a multi-axis machine interlocked with the two-axis machine. A first motor for driving, a first driving device, a second motor for driving the other of the two-axis machine, a second driving device, and a third motor to an n-th motor for driving other than the two-axis machine; In the motor drive device comprising: a third drive device to an nth drive device; and a controller that controls the first drive device to the nth drive device for each sampling time via a first transmission means. Comprises second transmission means for interconnecting the first to n-th driving devices (2) to (5) for transmitting position information obtained from the position detector, and the first in which an abnormality is detected. or position of the second driving device, the first addition The second driving unit (2), (3) is from the third to detect the abnormal transmission through the second transmission means to a driving device of the n, abnormality detected first or second drive Follows the position of the device (2), (3) and stops in such a way as to stop so that the deviation between the axes becomes small, or if there is distortion between the axes, an abnormality is detected while keeping the distortion A method of performing an emergency stop by following the position of the first or second driving device (2), (3) and stopping so that the deviation between the axes becomes small, or the abnormality is detected. When following the position of the first or second drive unit (2), (3) and stopping so that the deviation between the axes becomes small, the emergency stop is performed by lowering the control gain so that no interference occurs between the axes. The emergency stop is performed by any one of the methods .
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According to the first aspect of the present invention, the drive device for each axis monitors each other for deviation from each axis, and can make an abnormality above a certain inter-axis deviation. It is possible to stop while maintaining the deviation between the axes.
According to the second aspect of the invention, it is possible to stop so as to follow the position of the abnormality-generating drive device so as to reduce the deviation between the axes.
According to the third aspect of the present invention, the emergency stop is performed so as to follow the position of the abnormality-generating drive device so as to reduce the deviation between the axes, and after the stop, a predetermined stop method such as free run or dynamic brake is adopted. Can do.
According to the fourth aspect of the present invention, when there is distortion between the axes, it is possible to stop so as to follow the position of the abnormality-generating drive device so as to reduce the deviation between the axes while maintaining the distortion.
According to the fifth aspect of the present invention, if there is interference between the shafts, the control gain for following up can be lowered accordingly, and an emergency stop can be made without causing vibration or the like.
According to the sixth aspect of the present invention, the controller can monitor the positional deviation between the two axes that are mechanically coupled, and can make the abnormality more than a certain deviation between the axes. You can stop while keeping.
According to the seventh aspect of the present invention, the driving devices of the respective axes monitor each other for deviations from the respective shafts and make an abnormality when the deviation between the shafts exceeds a certain axis, and the abnormality-generating driving device is stopped by a dynamic brake or the like, so that it quickly stops. be able to.
According to the eighth aspect of the present invention, the drive device for each shaft includes the second transmission means for monitoring each other's deviation from each shaft, so that the deviation between the shafts is maintained without using a controller. Can be stopped.

  Hereinafter, specific examples of the method of the present invention will be described with reference to the drawings.

FIG. 1 shows the configuration of the first embodiment. In FIG. 1, 1 is a controller, 2 to 5 are a first drive device, a second drive device, a third drive device, and an nth drive device, and 6 to 9 are a first motor, a second motor, a third motor, and an nth motor. , 10 to 13 are a first position detector, a second position detector, a third position detector, an nth position detector, and 14 to 17 are sliders of the machine movable part, and the first slider, the second slider, and the third slider. The slider is the nth slider. Here, the first slider 14 and the second slider 15 are mechanically coupled by a fastening portion 18. The two motors of the first motor 6 and the second motor 7 are a so-called twin drive system that drives one axis as a synchronous control. Reference numeral 19 denotes first transmission means for connecting the controller 1 and the respective driving devices 2 to 5, and reference numeral 20 denotes second transmission means for connecting the respective driving devices 2 to 5.
In the driving devices 2 to 5, the driving devices 2 to 5 are connected by the second transmission means 20 that transmits the position information obtained from the position detectors 10 to 13, and the first or the first detecting the abnormality is detected. The positions of the second driving devices 2 and 3 are transmitted by the second transmission means 20 to the third to n-th driving devices 4 and 5 that detect abnormality.

Next, the operation will be described. The control of the mechanically coupled two axes is performed according to the control block shown in FIG. In FIG. 2, 21 is a first position control unit, 22 is a first speed control unit, 23 is a first torque control unit, 24 is a first speed conversion unit, 25 is a second position control unit, and 26 is a second speed control. , 27 is a second torque control unit, and 28 is a second speed conversion unit.
The controller 1 calculates the position command data of each axis for each sampling period as programmed, and transmits the position command data to the driving devices 2 to 5 via the first transmission means 19. Each drive unit 2-5 reads the position command data written in the memory or the like in each drive unit 2-5 through the first transmission means 19, and the position command data for each axis at the same time which is physically determined in advance. Becomes effective, and the motors 6 to 9 are driven.
When the driving devices 2 to 5 read the position command 19, the position command 19 is input to the position control units 21 and 25 together with the actual position detected by the position detectors 10 to 13.
The position control units 21 and 25 calculate the position deviation by subtracting the actual position from the position command, perform position control processing such as PI or PID calculation, and output the speed command to the speed control units 22 and 26.
The speed controllers 22 and 26 obtain the speed deviation by taking the difference between the speed command and the actual speed, perform control processing such as PI or PID calculation on the speed deviation, and output the torque command to the torque controllers 23 and 27.
The torque control units 23 and 27 convert the torque command into a current command, obtain the current deviation by taking the difference between the current command and the actual current, perform control processing such as PID processing, and convert the current deviation into a voltage command. The voltage command is power amplified through a power converter (not shown) and is supplied to the motors 6-9.
The driving devices 2 to 5 monitor state information such as position, speed, torque, and alarm in real time, and the monitored information is transmitted to the controller 1 through the first transmission means 19.
Further, the position information is transmitted between the driving devices 2 to 5 and the position detectors 10 to 13 through the second transmission means 20. Each drive device mutually reads the positions of the position detectors 10 to 13 and obtains an inter-axis deviation from the positions of its own axis and other axes. In addition, the second sampling of the second transmission means 20 can improve the accuracy by operating the second sampling of the first transmission means 19 in time synchronization.
When an abnormality occurs in the driving devices 2 to 5, the abnormality information is transmitted to the controller 1, and each driving device 2 to 5 is stopped by a predetermined operation in response to a command from the controller 1. The abnormality information includes an abnormality signal code that identifies the content of the abnormality, and the controller 1 determines the abnormality content by reading the abnormality signal code.
The abnormality of the drive devices 2 to 5 includes an abnormality that can maintain the motor drive and an abnormality that cannot maintain the motor drive. An overcurrent abnormality or an overvoltage abnormality is an abnormality that results in a component failure if a component in the drive unit 2 to 5 fails or if the motor drive is maintained as it is. Power conversion occurs when a predetermined abnormality detection level is exceeded. Immediately shuts off the drive of the power element of the device and outputs an abnormality occurrence signal. On the other hand, an abnormality such as an overload alarm or a battery voltage drop alarm does not immediately cause a failure even if the motor drive is maintained. Therefore, the motor 6 is not cut off simply by outputting an abnormality occurrence signal. ~ 9 can be driven normally.
When the abnormality occurrence driving device can normally drive the motors 6 to 9, all the axes are stopped based on the abnormal stop position command of the controller 1 so that the motors 6 to 9 can be normally stopped.
When the abnormality occurrence drive device cannot drive the motors 6 to 9 normally, the motors 6 to 9 are electrically disconnected and stopped by the method set by the user parameter. For example, the coasting distance can be minimized by using a dynamic brake that obtains braking torque by short-circuiting the motor terminal with a resistor.
The drive devices 2 to 5 that do not generate an abnormality stop based on the abnormal stop position command of the controller 1 when the abnormality generation drive device can drive the motors 6 to 9 normally.
When the abnormality occurrence driving device cannot drive the motors 6 to 9 normally, the follow-up operation is performed as an abnormality when the deviation between the axes is larger than the certain deviation based on the position information of the abnormality occurrence driving device. However, only the first driving device 2 and the second driving device 3 perform the tracking operation based on the position information of the abnormality-generating driving device. The block diagram shown in FIG. 2 is a case of a normal state, but it can also be applied to the case where the abnormality occurrence driving device can drive the motors 6 to 9 normally, and the position of the controller 1 according to the time chart shown in FIG. Stop as directed.
In this way, when the abnormality occurrence driving device cannot drive the motors 6 to 9 normally, a follow-up operation is performed as an abnormality more than a certain inter-axis deviation based on the position information of the abnormality occurrence driving device. Even if there is no transmission or the transmission is slow, it is possible to stop while maintaining the deviation between the axes. If there is distortion between the axes, the amount of distortion can be held as a position offset, and similarly, the axis can be stopped while maintaining the deviation between the axes.

Next, a second embodiment of the present invention will be described. The difference between the second embodiment and the first embodiment is that the drive device in which no abnormality has occurred is the same as the first embodiment in the follow-up operation point based on the positional information of the abnormality-generating drive device. SW2 switches the position command of the first drive unit 2 between the controller 1 and the actual position of the second drive unit 3, and SW2 switches the position command of the second drive unit 3 between the controller 1 and the actual speed of the first drive unit 2, SW3 switches whether the actual speed of the second drive unit 3 is added to the speed command of the first drive unit 2, and SW4 determines whether the actual speed of the first drive unit 2 is added to the speed command of the second drive unit 3. It is a point that has been changed.
When operating normally, there is a high probability that the abnormality-generating drive device cannot operate according to the position command data of the controller 1, and the main circuit is released from the power supply line and stopped by applying a dynamic brake. At this time, if the driving devices 3 to 5 in which no abnormality has occurred are rapidly decelerated and stopped, the dynamic brake has a weaker braking torque than the decelerating stop, so that a synchronization error occurs between the shafts. In order to suppress the occurrence of the synchronization error, the drive devices 3 to 5 in which no abnormality has occurred are operated following the position information of the abnormality occurrence drive device to reduce the synchronization error.
In FIG. 4, SW1 and SW2 select a position command for the controller 1 in a normal state, so that the first driving device 2 and the second driving device 3 perform a synchronous operation according to the command from the controller 1.
For example, when an abnormality occurs in the first drive device 2, the first drive device 2 applies a dynamic brake to the first motor 6 to stop it regardless of the command from the controller 1. At the same time, the position command of the SW2 controller 1 is disconnected and the actual position of the first drive device 2 is connected and used as a position command. By doing so, the second motor 7 operates following the operation of the first motor 6 in accordance with the time chart shown in FIG. Conversely, when an abnormality occurs in the second driving device 3, the first driving device 2 similarly follows the operation of the second driving device 3.
The stop operation command described above is issued by detecting an abnormality between the first drive device 2 and the second drive device 3 without going through the host controller 1. For this reason, the deceleration stop operation synchronized with high speed can be performed as compared with the case where the host controller 1 is interposed. A flow chart at this time is shown in FIG. If the deviation between the axes calculated in step 1 in this flow is equal to or greater than a certain deviation level, the process proceeds to step 2, and in step 2, the command is set to the position of the abnormality occurrence drive device and the follow-up operation is performed.
In this way, when the abnormality occurrence driving device cannot drive the motors 6 to 9 normally, a follow-up operation is performed as an abnormality more than a certain inter-axis deviation based on the position information of the abnormality occurrence driving device. Even without this, it is possible to stop while maintaining the deviation between the axes. Further, when interference occurs between the axes during the follow-up operation, the control gain is lowered to stop.

Next, a third embodiment of the present invention will be described. The third embodiment is different from the first and second embodiments in that the first or second driving device 2 or 3 is stopped by a predetermined stopping method such as a dynamic brake, and the third to nth detected abnormality is detected. The driving devices 4 and 5 are emergency stopped by the procedure of stopping by free run, dynamic brake, or the like based on the position of the first or second driving device 2 or 3.
The command from the controller 1 is transmitted to the first drive device 2 and the second drive device 4 through the first transmission means 19 as shown in FIG. 7, and the second drive device 3 is transmitted to the position detector 10 of the first drive device 2. The positions ˜13 are transmitted through the second transmission means 20.
When an abnormality occurs in the drive device 2, the abnormality information is transmitted to the controller 1 through the first transmission means 19, and each of the drive devices 3 to 5 stops in a predetermined operation. At this time, when the abnormality occurrence driving device can normally drive the motors 6 to 9, all the axes are stopped based on the abnormal stop position command of the controller 1. When the abnormality occurrence driving device cannot drive the motor 6 normally, the motor 6 is electrically disconnected, and the motor terminal is short-circuited by a resistor and stopped by a dynamic brake that obtains a braking torque.
The drive devices 3 to 5 that do not generate an abnormality stop based on the abnormal stop position command of the controller 1 when the abnormality generation drive device can normally drive the motors 7 to 9.
When the abnormality occurrence driving device cannot drive the motor 6 normally, the follow-up operation is performed based on the position information of the abnormality occurrence driving device. Here, only the first driving device 2 and the second driving device 3 perform the tracking operation based on the position information of the abnormality-generating driving device. That is, as shown in the time chart of FIG. 6, when an abnormality occurs in the first drive device 2, the second drive device 3 operates following the operation of the first motor 6, and the second drive device 3 When an abnormal operation occurs, the first drive device 2 operates following the operation of the second motor 7. If there is distortion between the axes, the amount of distortion is held as a position offset, and the follow-up operation is performed while maintaining the deviation between the axes. Further, when interference occurs between the axes during the follow-up operation, the control gain is lowered to stop.
In the present embodiment, an example in which two-axis sliders are mechanically coupled has been described, but the same applies to the case of three or more axes. Although the example of the rotary motor is described, the driving of the linear motor is the same.

    The present invention is applied to a large machine that cannot be driven by a single motor, a precision machine in which the drive shaft is divided into two or more on both sides in order to drive the center of gravity of the table. This is related to an emergency stop in which the positions of the two axes are synchronized so that no stress is applied to the machine when an abnormality occurs in one of the axes.

Configuration block diagram showing a first embodiment of the present invention Control block diagram at normal time showing the first embodiment of the present invention Time chart when the motor of the present invention can be driven normally Control block diagram when abnormality occurs in the second embodiment of the present invention Time chart when the motor of the present invention cannot be driven normally Emergency stop processing flowchart of the present invention Configuration block diagram showing a third embodiment of the present invention Schematic diagram showing the configuration of a conventional crankpin grinding device Time chart of conventional emergency stop method Block diagram of conventional emergency stop method

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Controller 2-5 1st-nth drive device 6-9 1st-nth motor
10 to 13 1st to n-th position detectors 14 to 17 1st to n-th slider 18 Fastening portion 19 First transmission means 20 Second transmission means 21 First position control portion 22 First speed control portion 23 First torque control Unit 24 first speed conversion unit 25 second position control unit 26 second speed control unit 27 second torque control unit 28 second speed conversion unit 22R, 22L hydraulic chuck 36R, 36L spindle motor 38R, 38L gear 40R, 40L encoder 42R , 42L Electromagnetic brake 48R, 48L Servo amplifier 54 CNC device 56 PLC device 58R, 58L Dynamic brake mechanism 101 PC 102 High-speed serial communication interface 103-105 Servo controller 106 First transmission 107 Second transmission

Claims (2)

A first motor and a first drive for driving one of the two-axis machines in a multi-axis drive device for driving a two-axis machine coupled by a fastening portion and a multi-axis machine interlocking with the two-axis machine Apparatus, second motor and second drive device for driving the other of the two-axis machine, third motor to n-th motor for driving other than the two-axis machine, and third drive to n-th drive a device consists of a controller for controlling to said n-th driving unit from the first drive unit via a first transmission means for each sampling time, abnormality in either the first or the second driving unit In the emergency stop method when it occurs,
The driving device using a second transmission means interconnecting between n-th driving unit from the first to transmit information of position obtained from the position detector (2) to (5), said first or said The inter- axis deviation between the second drive units (2) and (3) is monitored with each other, and an abnormality is detected when the first or second inter-axis deviation exceeds a set threshold, and the second transmission means (20) the first or second drive unit via a (2), (3) abnormal from the third detected n-th driving device, the position of the front Symbol first or second drive unit Based on the above, a method of following the position of the first or second driving device (2), (3) where the abnormality is detected, and making an emergency stop by a procedure of stopping so that the deviation between the axes becomes small, Alternatively, when there is a distortion between the axes, the first or second in which the abnormality is detected while maintaining the distortion. A method of performing an emergency stop by following the position of the moving devices (2) and (3) and stopping so as to reduce the deviation between the axes, or the first or second driving device (where the abnormality is detected) 2) When following the position of (3) and stopping so that the deviation between the axes becomes small, either of the methods of emergency stop with the control gain lowered to prevent interference between the axes An emergency stop method for a motor drive device characterized by stopping.
A first motor and a first drive for driving one of the two-axis machines in a multi-axis drive device for driving a two-axis machine coupled by a fastening portion and a multi-axis machine interlocking with the two-axis machine Apparatus, second motor and second drive device for driving the other of the two-axis machine, third motor to n-th motor for driving other than the two-axis machine, and third drive to n-th drive In a motor drive device comprising an apparatus and a controller for controlling from the first drive device to the n-th drive device at every sampling time via a first transmission means,
The drive device includes second transmission means for interconnecting the first to n-th drive devices (2) to (5) for transmitting position information obtained from a position detector, and an abnormality is detected. The position of the first or second driving device is connected to the third to nth driving devices that detect an abnormality in the first or second driving device (2) or (3) via the second transmission means. A method of making an emergency stop by a procedure of following the position of the first or second drive unit (2), (3) where the abnormality is detected and stopping so as to reduce the deviation between the axes, or When there is distortion between the axes, the position of the first or second driving device (2) or (3) where the abnormality is detected is maintained while the distortion is maintained, and stopped so that the deviation between the axes becomes small. The method of emergency stop by the procedure of performing the first or the first or In the case of following the positions of the second drive units (2) and (3) and stopping so that the deviation between the axes is small, the emergency stop is performed by lowering the control gain so that no interference occurs between the axes. A motor driving device characterized in that an emergency stop is performed by any method .

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