阅读说明：本技术 产业用机械的控制系统 (Control system for industrial machine ) 是由 小林大亮 出射敬 于 2020-03-18 设计创作，主要内容包括：本发明提供一种产业用机械的控制系统,在机械启动时,能够自动地检测出有无接线错误,防止伴随接线错误而发生电动机的高速旋转/高转矩等危险动作。产业用机械的控制系统(A)具备对产业用机械的驱动部(3)的驱动进行控制的控制部(2)以及向控制部(2)发出指令的指令部(1),还具备接线错误检测装置(10),在产业用机械启动时,该接线错误检测装置(10)基于驱动部(3)的实际驱动的反馈值来检测控制部(2)与驱动部(3)之间的系统内的接线错误。(The invention provides a control system for an industrial machine, which can automatically detect whether a wiring error exists when the machine is started, and prevent dangerous actions such as high-speed rotation and high torque of a motor caused by the wiring error. A control system (A) for an industrial machine is provided with a control unit (2) for controlling the drive of a drive unit (3) for the industrial machine, a command unit (1) for issuing a command to the control unit (2), and a wiring error detection device (10), wherein the wiring error detection device (10) detects a wiring error in the system between the control unit (2) and the drive unit (3) on the basis of a feedback value of the actual drive of the drive unit (3) when the industrial machine is started.)

1. A control system for an industrial machine, comprising a control unit for controlling the driving of a drive unit of the industrial machine, and a command unit for issuing a command to the control unit,

the control system for an industrial machine further includes a wiring error detection device that detects a wiring error in the system between the control unit and the drive unit based on a feedback value of actual driving of the drive unit when the industrial machine is started.

2. The industrial machine control system according to claim 1,

the wiring error detection means compares the feedback value, which is the current position of the drive portion, with a command value issued from the command portion to detect a wiring error.

3. The industrial machine control system according to claim 1,

the wiring error detection device compares a position deviation of the feedback value, which is a difference between the current position of the driving unit and a command value issued from the command unit, with an alarm detection threshold value of a position deviation preset for detecting a wiring error, and checks the wiring error.

4. A control system for an industrial machine, comprising a control unit for controlling the driving of a drive unit of the industrial machine, and a command unit for issuing a command to the control unit,

when the industrial machine is started, the industrial machine is started in a start mode in which the alarm threshold value or the torque limit value is forcibly lowered in order to prevent the machine from operating dangerously.

5. The industrial machine control system according to claim 4,

a wiring error detection device that detects a wiring error in a system between the control unit and the drive unit based on a feedback value of actual driving of the drive unit, and that includes a plurality of the drive units in the system,

the connection error detection device performs connection error detection for all the drive units, and switches to a normal operation mode if there is no connection error in all the drive units.

6. The industrial machine control system according to claim 5,

the wiring error detection device is provided with:

a starting mode confirming unit that confirms whether the machine is in a normal operation mode or a starting mode in which a warning detection threshold or a torque limit value is set lower than that in the normal operation mode, while detecting a power-on operation for the machine,

an abnormality detection unit that detects the presence or absence of a wiring error in a system between the control unit and the drive unit based on a feedback value in the start mode; and

and a wiring check command unit that receives a result of the detection when the start operation for the machine is detected by the start mode confirmation unit, and outputs a command for performing wiring check from the command unit to the control unit and the abnormality detection unit.

7. The control system of industrial machine according to any one of claims 1 to 3, 5, and 6,

the command unit acquires the feedback value at a time point after a fixed time has elapsed since the start of driving of the drive unit or at a plurality of time points in an arbitrary time period after the fixed time has elapsed, and detects a wiring error in the system between the control unit and the drive unit based on the feedback value.

8. The industrial machine control system according to claim 6 or 7,

the wiring inspection operation unit is provided, and the wiring inspection operation unit outputs a command for performing wiring inspection from the wiring inspection command unit to the control unit and the abnormality detection unit at an arbitrary timing.

9. The industrial machine control system according to any one of claims 1 to 8,

the control system for an industrial machine is configured to: a plurality of driving parts are arranged in a system of a control system, and feedback values of actual driving of the driving parts are respectively obtained from all the driving parts.

10. The industrial machine control system according to any one of claims 4 to 9,

the control system of the industrial machine is configured to be set to the start mode at an arbitrary timing.

11. The industrial machine control system according to any one of claims 4 to 10,

normal operation is not possible while in the start-up mode.

Technical Field

The present invention relates to a control system for an industrial machine.

Background

For example, in the field of machine work, a CNC (computer numerical control) technique is applied to numerically control the movement amount, movement speed, and the like of a tool by a computer, thereby highly automating repetition of the same machining process, machining of complex shapes, and the like.

Further, for example, the following control systems are known as control systems for industrial machines such as machine tools and robots: a servo amplifier (control unit) is provided between a CNC (command unit) and a servo motor (drive unit) of a machine, and the servo amplifier receiving an operation command from the CNC performs feedback control on the drive of the servo motor (see, for example, patent document 1, patent document 2, and patent document 3).

On the other hand, for example, as shown in fig. 1, when there is a wiring error between the CNC 1, the servo amplifiers 2(2a, 2b), and the servo motors 3(3a, 3b) of the machine, there is a possibility that an unexpected operation may occur at the time of starting the machine. That is, when the power lines 4(4a, 4b) and the feedback lines 5(5a, 5b) are connected to the servo amplifiers 2(2a, 2b) and the motors 3(3a, 3b) of the machine, and when the feedback lines 5(5a, 5b) are connected to the wrong motors 3(3a, 3b), the difference between the command value and the feedback value from the CNC 1 gradually increases, and there is a possibility that a high-speed rotation/high-torque dangerous operation may occur in the motor 3a (3b) to which the feedback line 5a (5b) should be originally connected.

Therefore, conventionally, there is a control system for an industrial machine, which is configured as follows: an alarm (warning) is issued before the unexpected operation reaches a dangerous level, thereby avoiding an accident or the like due to a wiring error of the motor 3 as a driving unit of a machine tool, a robot or the like.

Disclosure of Invention

Problems to be solved by the invention

Here, in order to avoid the motor from being driven at a high speed and by a dangerous operation of high torque due to such a wiring error, it is explicitly described in a servo parameter specification or the like that "when a connection or a setting error of a device occurs, an unexpected operation may occur, and therefore, when a machine is first operated after being assembled, a component is replaced, and a parameter is changed, it is necessary to carefully operate the machine such as an operation for lowering a torque limit value, lowering an excessive error level, lowering an operation speed, and immediately stopping urgently" to remind a user side (an operator side) of the industrial machine.

However, since the operation of lowering the alarm threshold value for issuing an alarm before the unexpected operation reaches a dangerous level is generally performed by the user side of the industrial machine, it cannot be completely excluded that the user side forgets to lower the alarm threshold value, and if the user side forgets to lower the alarm threshold value, the motor may still be driven by a dangerous operation such as high-speed rotation and high torque at the time of starting the machine.

Therefore, it is strongly desired to develop a means/method capable of automatically detecting the presence or absence of a wiring error at the time of starting a machine and preventing dangerous operations such as high-speed rotation and high torque of a motor from occurring due to the wiring error.

Means for solving the problems

One aspect of the present invention is a control system for an industrial machine, including a control unit that controls driving of a drive unit of the industrial machine, and a command unit that issues a command to the control unit, and further including a wiring error detection device that detects a wiring error in a system between the control unit and the drive unit based on a feedback value of actual driving of the drive unit when the industrial machine is started.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the above-described aspect, when the machine is started, a wiring error between the drive unit and the control unit of the industrial machine such as a machine tool or a robot can be automatically detected, and occurrence of an unexpected operation on the machine side due to the wiring error can be prevented.

Drawings

Fig. 1 is a diagram illustrating a control system of an industrial machine according to an embodiment.

Fig. 2 is a diagram illustrating a control system and a wiring error detection device of an industrial machine according to an embodiment.

Fig. 3 is a diagram showing an example of the positional deviation limit value (alarm detection threshold value) in the normal operation and the start mode.

Fig. 4 is a diagram for explaining a method of detecting a wiring error by a control system of an industrial machine according to an embodiment.

Description of the reference numerals

1: CNC (numerical controller, command unit, higher-level control unit); 2a servo amplifier (control unit); 3: a servo motor (drive unit); 4: a power line; 5: a feedback line; 6: a signal line; 7: a signal line; 10: a wiring error detection device; 11: a start mode confirmation unit; 12: an operation instruction unit; 13: a wiring inspection command unit; 14: a storage unit; 15: a storage unit; 16: an abnormality detection unit; 17: a start mode forced termination unit; 18: a display unit; 19: an alarm unit; 20: a wiring inspection operation unit; 21: an instruction value acquisition unit; 22: a feedback value acquisition unit; 23: a selection unit; 24: a wire connection check confirming unit; a: provided is a control system for an industrial machine.

Detailed Description

A control system for an industrial machine according to an embodiment of the present invention will be described below with reference to fig. 1 to 4.

Here, although the present embodiment is described with reference to the industrial machine being a machine tool, the present invention is applicable to all machines having a driving unit whose driving is automatically controlled by a control unit, such as an industrial robot.

As shown in fig. 1, a control system a of a machine tool (control system of an industrial machine) according to the present embodiment includes: a servomotor (motor: drive unit) 3 for a machine tool such as an NC lathe or a machining center; a servo amplifier (control unit) 2 that controls driving of a motor 3 of the machine tool; and a CNC (computer numerical control device, higher-level control unit) 1 that controls the entire control system a of the machine tool at a higher level than the servo amplifier 2.

The control system a of the machine tool according to the present embodiment includes a plurality of machine tools (a plurality of servomotors 3(3a, 3b)) and a plurality of servoamplifiers 2(2a, 2b), and the servomotors 3(3a, 3b) and the servoamplifiers 2(2a, 2b) of a pair of machine tools are connected to each other by power lines 4(4a, 4b) and feedback lines 5(5a, 5 b).

In the present embodiment, the CNC 1 is connected to one servo amplifier 2a through a signal line 6, and the plurality of servo amplifiers 2a and 2b are connected through a signal line 7. Thereby, the CNC 1 is directly and indirectly connected with the plurality of servo amplifiers 2(2a, 2 b).

Fig. 1 is a diagram showing a state in which a wiring error has occurred by connecting a feedback line 5a that originally connects a servo amplifier 2a and a servo motor 3a to the servo amplifier 2a and the servo motor 3b, and connecting a feedback line 5b that originally connects a servo amplifier 2b and a servo motor 3b to the servo amplifier 2b and the servo motor 3 a.

On the other hand, as shown in fig. 2, the control system a of the machine tool according to the present embodiment includes a wiring error detection device 10, and the wiring error detection device 10 is configured to detect a wiring error (wiring error in the system) between the servo amplifier 2 and the servo motor 3 of the machine tool. The wiring error detection device 10 may be incorporated into the CNC 1 or may be separately provided.

The wiring error detection device 10 is configured to include a start mode confirmation unit 11, an operation instruction unit 12, a wiring check instruction unit 13, storage units 14 and 15, an abnormality detection unit 16, a display unit 18, an alarm unit 19, and a wiring check operation unit 20.

The activation mode confirming unit 11 confirms and determines whether the normal operation mode or the activation mode is performed while detecting an activation operation for the machine.

When the normal operation mode is confirmed by the start mode confirming unit 11, the operation command unit 12 receives the result of the detection and outputs an operation command to the servo motor 3 via the servo amplifier 2 of the control unit.

When the abnormality detection unit 16, which will be described in detail later, does not detect a wiring error, the operation command unit 12 receives the detection result from the abnormality detection unit 16, and starts and continues the operation control of the machine in accordance with the command value from the CNC 1.

The wiring check command unit 13 receives the result of the detection while the start mode confirming unit 11 detects the start operation for the machine, and outputs a command for performing wiring check to the servo amplifier 2 and the abnormality detecting unit 16.

The storage units 14 and 15 store a warning detection threshold (or torque limit value) for the normal operation mode and a warning detection threshold (or torque limit value) for the start mode, respectively.

The abnormality detection unit is for checking and determining the presence or absence of a wiring error between the servo amplifier 2 and the servo motor 3, and includes a command value acquisition unit 21, a feedback value acquisition unit 22, a selection unit 23, and a wiring check checking unit 24.

The command value acquisition unit 21 receives a command for wire connection inspection from the wire connection inspection command unit 13 and acquires command values from the CNC 1 (for example, drive command values such as the rotational speed and torque of each servo motor 3, and position command values of each servo motor 3).

The feedback value acquiring unit 22 receives the instruction of the wire connection inspection from the wire connection inspection instructing unit 13 and acquires the feedback value indicating the driving state of the actual driving of each servo motor 3. In the present embodiment, a position deviation, which is a difference between the current position of the servo motor (driving unit) 3 and the command value, is a feedback value. The feedback value may also be a value corresponding to a command value from the CNC 1 (for example, the current position of each servo motor 3).

In this case, the feedback value acquiring unit 22 is configured to, for example: the servo motor driving device is provided with a timer, and acquires a feedback value of a fixed time at which a measured value is stable and a measurement can be performed with high accuracy at a time (a time after a fixed time has elapsed) after a predetermined fixed dead time has elapsed from the start of driving of the servo motor 3.

Further, the present invention may be configured such that: the feedback values are acquired at a plurality of times in an arbitrary time period (a plurality of times in an arbitrary time period after a fixed time period has elapsed) after a fixed dead time set in advance has elapsed since the servo motor 3 starts driving.

The selector 23 selectively acquires the alarm detection threshold for the start mode and the alarm detection threshold for the normal operation from the storage units 14 and 15. As a result, as shown in fig. 3, the alarm detection threshold for the start mode is automatically set even if the user side (operator side) of the machine does not change the setting during the start mode. I.e. the alarm threshold drops. In addition, during normal operation, the alarm threshold value is still automatically changed to the alarm detection threshold value for normal operation. I.e. the alarm threshold rises.

The wiring check confirming unit 24 determines the presence or absence of a wiring error based on the magnitude of the feedback value (positional deviation) acquired by the feedback value acquiring unit 22. That is, the feedback value is compared with a preset alarm detection threshold value to determine whether or not a wiring error has occurred.

For example, when the positional deviation of the feedback value exceeds the allowable value, it is determined that a wiring error has occurred, and when the positional deviation satisfies the allowable value, it is determined that no wiring error has occurred. The allowable value is an alarm detection threshold value for the startup mode, and is acquired from the storage unit 14.

Here, when the feedback value is a value corresponding to the command value from the CNC 1, the difference between the command value acquired by the command value acquiring unit 21 and the feedback value is obtained, and the presence or absence of the wiring error is determined based on whether or not the difference exceeds a preset allowable value (alarm detection threshold). For example, the wire connection check unit 24 may be configured to detect a wire connection error by comparing a feedback value, which is the current position of the servo motor 3, with a command value (position command value of the servo motor 3) issued from the CNC 1.

When the abnormality detection unit 16 determines that a wiring error has occurred, a warning sound is generated or a warning lamp is turned on by the alarm unit 19 based on the result, and the occurrence of the wiring error is displayed on the display unit 18 to be notified to an operator or the like. In addition, control is performed so as to avoid unexpected dangerous operation/abnormal operation in the servo motor 3 due to a wiring error. Specifically, the following control is performed: the alarm threshold value is not increased to the alarm threshold value for normal operation, and the operation mode is not shifted to the normal operation mode.

When the abnormality detection unit 16 determines that the wiring error has not occurred, the result is sent to the operation command unit 12, and the operation command unit 12 detects that the machine has started normally and issues a command to the servo amplifier 2 so that the normal operation is performed in accordance with the command value of the CNC 1.

When the abnormality detection unit 16 determines that no wiring error has occurred, the display unit 18 displays a normal state and notifies an operator or the like of the normal state.

When the abnormality detector 16 determines that no wiring error has occurred, the selector 23 acquires the normal operation alarm detection threshold from the storage unit 15, switches the alarm detection threshold during normal operation after start-up to the normal operation alarm detection threshold, and automatically raises the alarm threshold.

Here, in the control system a of the machine tool according to the present embodiment, the wiring error detection device 10 is provided with the wiring inspection operation unit 20, and the wiring inspection operation unit 20 is operated regardless of the start of the machine, so that the wiring inspection command unit 13 issues a command to perform the wiring inspection in the same manner as described above.

Thus, for example, when only a part of the wiring work of the system is completed, when the replacement work of the maintenance member is performed, or at an arbitrary timing when the wiring inspection is desired, the wiring inspection operation unit 20 can be operated to perform the wiring inspection.

That is, in the control system a of the machine tool according to the present embodiment, as described above, the start mode (wire check mode) is set, and the CNC 1 automatically lowers the alarm threshold value (or torque limit value) to the value for the start mode provided therein.

Then, the CNC 1 issues a command, checks the wiring by checking the feedback value, exits the start mode and switches to the normal operation mode if the wiring states of all the servo motors 3 are correct, and issues a warning from the alarm unit 19 or displays an abnormal state on the display unit 18 if the wiring states of the servo motors 3 are abnormal.

Therefore, in the control system a of the industrial machine such as the machine tool according to the present embodiment, the wiring error detection device 10 that detects the wiring error in the system based on the feedback value is provided, and the wiring error detection device 10 detects the wiring error by comparing the threshold value, the feedback value (or the difference between the command value and the feedback value), and the alarm detection threshold value that are set in advance for detecting the wiring error, whereby the wiring error between the servo motor 3 of the drive unit and the servo amplifier 2 of the control unit can be automatically detected at the time of starting the machine or the like, and the occurrence of an unexpected operation on the machine side due to the wiring error can be prevented.

The connection error detection device 10 further includes: a starting mode confirming unit 11 that confirms whether the machine is in the normal operation mode or the starting mode while detecting a starting operation for the machine; an abnormality detection unit 16 that detects the presence or absence of a wiring error in the system; and a wiring check command unit 13 that receives a result of the detection while the start operation for the machine is detected by the start mode confirming unit 11, and outputs a command for performing wiring check to the servo amplifier 2 and the abnormality detecting unit 16.

Thus, when the machine is started, a wiring error between the servo motor 3 of the drive unit and the servo amplifier 2 of the control unit is automatically detected, and it is possible to reliably prevent an unexpected operation from occurring on the machine side due to the wiring error.

The connection error detection device 10 further includes: a command value acquisition unit 21 that receives a command for the wire connection inspection from the wire connection inspection command unit 13 and acquires a command value; a feedback value acquisition unit 22 that acquires a feedback value; a selection unit 23 that selectively acquires the threshold value for the startup mode and the threshold value for the normal operation stored in the storage units 14 and 15; and a wiring check confirming unit 24 for comparing the feedback value with a threshold value for the start mode to determine whether or not a wiring error exists.

Thus, at the time of starting the machine, a wiring error between the servo motor 3 of the drive unit and the servo amplifier 2 of the control unit is automatically detected using the threshold value for the start mode, and it is possible to more reliably prevent an unexpected operation from occurring on the machine side due to the wiring error. In addition, the presence or absence of an abnormality can be detected using a threshold value for normal operation together with the change to the normal operation mode.

In addition, the operation may be started in the start mode, the connection error detection device 10 may detect connection errors of all the servomotors (driving units) 3, and if there is no connection error in all the servomotors 3, the operation may be automatically switched to the normal operation mode.

Next, in the present embodiment, the feedback value acquiring unit 22 is configured to acquire the feedback value for a fixed time after the actual driving of the servo motor 3 is stabilized after the driving of the servo motor 3 is started.

Thus, the wiring inspection is not performed based on the feedback value of the state in which the actual driving of the servo motor 3 is unstable immediately after the start operation for the machine is performed, and the wiring error inspection with high reliability can be performed.

The wiring inspection operation unit 20 is provided, and the wiring inspection operation unit 20 outputs a command for performing wiring inspection from the wiring inspection command unit 13 to the servo amplifier 2 and the abnormality detection unit 16 at an arbitrary timing.

Accordingly, regardless of the start of the machine, the wiring inspection command unit 13 can output a command to perform wiring inspection by operating the wiring inspection operation unit 20. For example, the wiring inspection operation unit 20 can be operated to perform the wiring inspection at an arbitrary timing when the wiring operation is to be performed only in a part of the system, when the replacement operation of the maintenance component is performed, or the like.

Thus, according to the control system a of the industrial machine of the present embodiment, even if an unexpected operation is caused by a wiring error, the operation can be stopped at a safe level. In addition, a wiring error can be automatically detected by a wiring check.

Although the embodiment of the control system for an industrial machine according to the present invention has been described above, the present invention is not limited to the above embodiment, and can be modified as appropriate without departing from the scope of the invention.

For example, in the present embodiment, the following configuration is explained: the system is provided with a plurality of control units (servo amplifiers 2) and a plurality of drive units (servo motors 3), and detects a wiring error of the feedback line 5 when the power lines 4 and the feedback line 5 for the control units and the drive units are connected one by one.

In contrast, the control system for an industrial machine according to the present invention can be applied to a case where the industrial machine includes one control unit and one driving unit. For example, when a three-phase motor (three phases: UVW) is connected or wired incorrectly, a feedback value of the three-phase motor is acquired and compared with a command value (or a threshold value), thereby detecting the connection error of the three-phase motor. This can provide the same operational effects as those of the present embodiment.

In addition, the start mode may be set at an arbitrary timing.

Further, the starting mode may be configured to start the machine in such a manner that the warning threshold value or the torque limit value is forcibly lowered in order to prevent the machine from causing a dangerous operation when the machine is started.

In addition, when a plurality of servomotors (drive units) 3 are provided in the system of the control system a of the industrial machine as in the present embodiment, it is preferable to configure the feedback values of the actual drive of the servomotors 3 to be acquired from all the servomotors 3.

When a wiring error exists in the system, there is a possibility that an erroneous feedback (feedback value) is acquired not only from the servo motor 3 that has transmitted the command but also from another servo motor 3. Therefore, by configuring all the servomotors 3 as the targets for acquiring the feedback values as described above, it is possible to detect a wiring error more accurately and with higher accuracy.

The torque limit value at the time of sending the wiring error detection command (start mode) may be set to a value to the extent that the machine can move to the commanded position.