JP2008225987A - Process abnormal condition automatic extracting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To automatically extract abnormality for each of the control processes to a machine controlled by a programmable controller. <P>SOLUTION: The system includes a first step for defining the process execution time required to execute each of the control processes for controlling the machine by the programmable controller, a second step for setting fixed allowable time range to the defined process execution time, a third step for setting the abnormal condition of the process, and a fourth step for setting the abnormal contents, according to the abnormal conditions for each of the control processes. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a process abnormality condition automatic extraction system that automatically extracts an abnormality for each control process in which a machine is controlled by a programmable controller (PLC).

  Conventionally, a programmable controller has been widely used for various processes such as welding machines or control of machine tools. And in the conventional programmable controller, when abnormality occurs in the process of controlling the operation of various machines, it is necessary to investigate the cause.

  On the other hand, since there are many inspection or detection items such as abnormalities in the control process in the conventional programmable controller, when the process abnormality occurs, the abnormality occurrence message and the abnormality occurrence detected, for example, in the relay Proposals have been made to display numbers and the like to assist workers in investigating the causes of abnormalities. (See Patent Document 1).

However, since the control process by a programmable controller is generally complicated and diverse, it is difficult to check whether an abnormality has occurred for each control process, and it is difficult to require skilled techniques, and whether the abnormality has occurred. It is not easy and troublesome to set the determination conditions for such a determination criterion on the operator side.
JP 09-179607 A

  In the present invention, process abnormal conditions for each control process can be automatically extracted, and even when the control process is complicated and diverse, the occurrence of abnormality for each control process can be easily detected without requiring time and skill. It is.

  The process abnormal condition automatic extraction method according to the present invention is based on the first step for defining the process execution time required to execute the process for each control process for controlling the machine by the programmable controller and the process execution time according to the above definition. Including a second step of setting a certain allowable time range, a third step of setting an abnormal condition in the process, and a fourth step of setting an abnormality content corresponding to the abnormal condition for each control process. It is a feature.

  According to the present invention, even if the control process by the programmable controller is complicated and diverse, the process execution time is automatically defined for each control process, and it is managed whether the process execution time is outside the allowable time range or this process. As a result, the operator can know the details of the abnormality only by setting the abnormal condition in step 3. As a result, the operator can efficiently monitor and maintain the location where the process abnormality has occurred. .

  It is preferable to include at least a fifth step of displaying an abnormality content corresponding to the control process. This display may be displayed on the display screen of a personal computer, or may be displayed on the display screen of a programmable display. Further, a display screen can be arranged on the programmable controller and displayed on the display screen. Alternatively, it can be displayed wirelessly on the display screen of the mobile device. Or you may display on display screens, such as a personal computer, a programmable display, a mobile device, via the internet.

  It is preferable to display the results of the second to fourth steps in the form of a diagnostic table on a display screen of a personal computer, a programmable display, or other equipment.

  According to the present invention, the process abnormality for each process can be automatically extracted in the control of the machine by the programmable controller. Therefore, it is possible to efficiently find the circuit or the like in which the process abnormality has occurred and take necessary measures.

  Hereinafter, a process abnormal condition automatic extraction method according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a schematic configuration of a transport machine control system using a programmable controller. The control system 10 includes a transport machine 12 as an example of a control target, a programmable controller 14 that controls the transport machine 12 in sequence, a personal computer 16 that gives a control command or the like to the programmable controller 14, and the like.

  The transport machine 12 includes a plurality of actuators 18 for driving transport elements of the transport machine 12 such as an arm and a chuck, and a plurality of sensors 20 for detecting an operation state of the transport machine 12. A power supply (not shown) is supplied to the actuator 18 and the sensor 20 of the transport machine 12. The programmable controller 14 includes an I / O control circuit 22, a CPU 24, a communication I / F 26, a ROM 28, a RAM 30, a timer 32, and the like.

  The I / O control circuit 22 mediates the exchange of signals between the CPU 24 and the transport machine 12, outputs the output signal of the CPU 24 to the actuator 18 of the transport machine 12, and outputs the detection signal of the sensor 20 of the transport machine 12. Input and transfer to CPU24.

  The CPU 24 executes various controls of the transport machine 12 and the programmable controller 14, and controls operations of the I / O control circuit 22, the communication I / F 26, the ROM 28, the RAM 30, the timer 32, and the like.

  The communication I / F 26 mediates data exchange between the CPU 24 and the personal computer 16, outputs an output signal of the CPU 24 to the personal computer 16, and transfers an instruction command from the personal computer 16 to the CPU 24. The communication I / F 26 and the personal computer 16 are connected via a dedicated communication cable.

  The ROM 28 stores various operation programs for the CPU 24 to execute various controls.

  The RAM 30 temporarily stores data read from the ROM 28 when the CPU 24 executes various controls, data generated when the CPU 24 executes various controls, various data generated during the control of the transport machine 12, and the like. Stored.

  The timer 32 is used for measuring the process execution time, and is driven and controlled by the CPU 24.

  The programmable controller 14 controls the operation of the transport machine 12 by controlling the power supply to each actuator 18 of the transport machine 12 in accordance with the instruction command transferred from the personal computer 16, and The equipment state of the transport machine 12 is detected based on the detection signal of each sensor 20, and the equipment state is notified to the personal computer 16.

  The personal computer 16 is connected to the programmable controller 14 by, for example, RS232C. The personal computer 16 can perform graphic display using a CRT, a liquid crystal display, or the like, and includes a keyboard 16a and a mouse 16b for performing a cursor operation. Communication between the personal computer 16 and the programmable controller 14 is not limited to RS232C, and may be performed by RS422, Ethernet (registered trademark), or the like.

  Through the communication, data representing the operating state of the actuator 18, the sensor 20, and the like is transmitted from the programmable controller 14 to the personal computer 16.

  FIG. 2 illustrates the transport machine 12 controlled by the programmable controller 14. The transport machine 12 is a machine for transporting a workpiece 44. A stage 34 is erected on a table 33, and a horizontal arm 36 that can be expanded and contracted in the horizontal direction is mounted on the stage 34, and at the tip of the horizontal arm 36. A fixing member 38 is attached. A vertical arm 40 that is vertically extendable is attached to the lower end of the fixing member 38, and a chuck 42 is fixed to the vertical arm 40. Note that illustrations of various actuators 18 for operating the transport machine 12, various sensors 20 for detecting the operation state of the transport machine 12, the programmable controller 14, and the like are omitted for the sake of brevity.

  With reference to FIG. 3, the workpiece 42 on the table 33 is transferred from the position X to the position Y by controlling the lowering, raising and moving of the chuck 42 in the order of (a), (b), (c), (d) and (e). The operation of the transporting machine 12 will be described.

  In step S1, the origin position (a) of the chuck 42 is confirmed.

  In step S2, the chuck 42 is lowered from the origin position (a) to the position (b), and the chuck 42 is closed and the workpiece 44 is grasped at the lowered position (b).

  In step S3, the chuck 42 is closed and raised to the origin position (a).

  In step S4, the chuck 42 is closed and moved horizontally from the origin position (a) to the position (d).

  In step S5, the chuck 42 is closed and lowered from the position (d) to the position (e). The chuck 42 is opened at the lowered position (e), and the workpiece 44 is placed on the table 33.

  In step S6, the chuck 42 is returned from position (e) to position (a).

  The programmable controller 14 stores a process step type program for executing the above-described processes S1 to S6 in the RAM 30.

  The display screen 50 of the personal computer 16 will be described with reference to FIGS. The display screen 50 shown in FIG. 4A displays the transport machine 12 shown in FIG. 2, and FIG. 4B shows a diagnosis for diagnosing an abnormal state of the transport machine on the display screen 50. The front window 52 is called up and displayed. FIG. 5 shows the diagnostic table window 52 in an enlarged manner. The display in the diagnosis table window 52 will be described with reference to FIG. Is filled with the numbers of the above steps S1-S6, "Diagnosis condition" is filled with "Over time", "Short time", and "Abnormal condition", and "Abnormal content" is filled with a comment.

  In creating and displaying this diagnostic table, the personal computer 16 controls the transport machine 12 by the programmable controller 14, and the process execution time (required for execution of the steps S1-S6 for each control step S1-S6 in the control) ( Definition process execution time) is defined. The definition process execution time can be defined according to the hardware performance of the transport machine 12. This definition process execution time is automatically defined. For example, the teaching process is performed before the actual process is performed. In this case, there are various modes depending on the motor for controlling the transport machine 12, the expansion / contraction distance of the arms 16 and 40, the lowering, raising and moving distance of the chuck 42, etc. For example, the average process execution time of each process S <b> 2 to S <b> 6 is measured by the timer 32, and the measurement result is stored in the RAM 30. Step S2 is 0.8 seconds, step S3 is 1.0 seconds, step S4 is 1.8 seconds, step S5 is 0.8 seconds, and step S6 is 2.8 seconds.

  The actual process execution time, which is the time required to execute the actual process in each of the steps S2-S6, is outside the allowable time range with respect to the allowable time range set for the definition process execution time stored in the RAM 30. A time that is “over time” and a time that is “short time” are set. In this setting, the process execution allowable error time is set in the RAM 30 for each process, and the actual process execution time and the calculation result are automatically set to “over time” and “short time”. This setting can also be performed by an operator.

  “Over time” of the actual process execution time required when the actual process is performed in each of the processes S2 to S6 is, for example, 1.0 seconds, 1.2 seconds, 2.0 seconds, 1.0 seconds, and 3.2. The “short time” in steps S2-S6 is, for example, 0.6 seconds, 0.8 seconds, 1.6 seconds, 0.6 seconds, and 2.4 seconds.

  Since step S1 is a step of confirming the origin position (a) of the chuck 42, “excessive time” and “short time” in the diagnosis condition are not entered, and the “abnormal condition” indicates that the chuck 42 is in the origin position sensor ON. There is a normal state, and a chuck origin position sensor OFF signal is entered and displayed as an abnormal condition. “Sensor on” is a state in which, for example, a proximity sensor, which is an example of a sensor, detects that the chuck 42 exists at the origin position and outputs a sensor signal of a certain level or more. “Sensor off” means that the proximity sensor Since the chuck 42 does not exist at the origin position, it can be defined as a state in which the chuck 42 cannot be detected and a sensor signal below a certain level is output.

  As for “abnormal content”, when the chuck 42 is not present at the origin position, a “sensor off” signal is received and a comment is entered and displayed as “the chuck does not exist at the origin position (a)”. These comments are stored and stored in advance in the RAM 30 or the like of the programmable controller 14 so that the CPU 24 can transmit these comments to the personal computer 16 by “sensor on” and “sensor off”. The transmission of these comments is the same in the following steps.

  In step S2, the chuck 42 is lowered from the origin position (a) to the position (b), the chuck 42 is closed at the lowered position (b), and the workpiece 44 is grasped. The definition process in the step S2 is performed. The time is 0.8 seconds required for normal operation. “Over time” is 1.0 second or more, and “Short time” is 0.6 second or less. When the actual process execution time until the chuck 42 is lowered from the origin position (a) to the position (b) takes 1.0 second or more, the lowering speed of the chuck 42 is too slow, and the chuck 42 is moved to the origin position (a If the actual process execution time is 0.6 seconds or less until the position is lowered from position (b) to position (b), the lowering speed is too fast, and there is an abnormality in the motor for lowering the chuck 42, its circuit, or the like.

  In this process, since there is no “abnormal condition”, it is not displayed. If the “abnormal content” is out of the allowable time range, for example, if the cause is a lift motor abnormality, a comment “lift motor abnormality” is entered and displayed. In this case, by setting a plurality of types of sensors in corresponding locations, for example, “elevating motor overheating abnormality”, “elevating motor disconnection abnormality”, “elevating motor overvoltage abnormality”, for each type of sensor, A comment such as “vertical arm abnormality” may be entered and displayed.

  In step S3, since the chuck 42 is raised to the origin position (a), the definition process execution time is 1.0 second, and when “over time” is 1.2 seconds or more, “short time” is This is the case for 0.8 seconds or less. If the actual process execution time is 1.0 second or longer before the chuck 42 is moved from the position (b) to the position (a), the ascending speed of the chuck 42 is too slow. Since the rising speed is too high, there is an abnormality in the lifting motor that raises the chuck 42, its circuit, or the like. The “abnormal condition” in this process is, for example, a case where the chucked workpiece is dropped for some reason, and a workpiece sensor OFF signal is entered and displayed. If “abnormal content” is outside the allowable time range, for example, “lifting motor abnormality” is entered and displayed, and if “abnormal condition” occurs, for example, “workpiece drop” is entered and displayed. In this case as well, by setting a plurality of types of sensors in corresponding locations, for example, “elevating motor overheating abnormality”, “elevating motor disconnection abnormality” Comments such as “lift motor overvoltage error”, “vertical arm error”, “chuck failure, workpiece drop”, etc. may be entered and displayed.

  In step S4, the chuck 42 is moved horizontally from the origin position (a) to the position (d). Therefore, the definition process execution time is 1.8 seconds, and “over time” is 2.0 seconds or more. “Short time” is 1.6 seconds or less. If it takes 2.0 seconds or more for the chuck 42 to move from the position (a) to the position (d), the moving speed of the chuck 42 is too slow, and if it takes 1.6 seconds or less, the moving speed Is too fast, the motor for moving the chuck 42, its circuit, etc. may be abnormal. The “abnormal condition” in this step is the fall of the chucked workpiece as in S3, and a workpiece sensor OFF signal is entered and displayed. If “abnormal content” is outside the allowable time range, for example, “moving motor abnormality” is entered and displayed, and if “abnormal condition” occurs, “workpiece drop” is entered and displayed. In this case as well, by setting multiple types of sensors to the corresponding locations, “Moving motor overheating error”, “Moving motor disconnection error”, “Moving motor overvoltage error”, “Vertical arm error” for each type of sensor. A comment such as “chuck failure, workpiece drop” may be entered and displayed.

  In step S5, the chuck 42 is lowered from the position (d) to the position (e), the chuck 42 is opened at the lowered position (e), and the workpiece 44 is placed on the table 33. Is 0.8 seconds, “over time” is 1.0 second or longer, and “short time” is 0.6 second or shorter. When it takes more than 1.0 seconds for the chuck 42 to descend from the position (b) to the position (a), the lowering speed of the chuck 42 is too slow. As a result, there is an abnormality in the lifting motor or its circuit. In this process, the “abnormal condition” is not set, so it is left blank. If “abnormal content” is outside the allowable time range, for example, “lifting motor abnormality” is entered and displayed.

  In step S6, since the chuck 42 is returned from the position (e) to the position (a), the definition process execution time is 2.8 seconds, and “over time” is 3.2 seconds or more. “Short” is the case of 2.4 seconds or less. If the actual process execution time takes 3.2 seconds or more until the chuck 42 returns from the position (e) to the position (a), the chuck 42 speed is too slow. Is too fast, there is an abnormality in the lifting motor, moving motor and its circuit. Even in this process, the “abnormal condition” is not set, so it is left blank. If “abnormal content” is outside the allowable time range, for example, “lifting motor abnormality”, “moving motor abnormality”, etc. are entered and displayed.

  As described above, in the present embodiment, in the control of the machine by the programmable controller, the process abnormality for each process is automatically extracted, and the circuit in which the process abnormality is arranged and the cause of the abnormality are efficiently displayed from the display of the diagnosis table. You can discover and take necessary measures.

FIG. 1 is a diagram showing an outline of a programmable controller, a personal computer, and a transport machine that implement the process abnormal condition automatic extraction system according to the embodiment of the present invention. FIG. 2 is a diagram showing an outline of a transport machine controlled by the programmable controller. FIG. 3 is a diagram showing a process by a programmable controller. 4A is a view showing an example of a display screen of a personal computer transport machine, and FIG. 4B is a view showing an example of a display screen in which a diagnostic table window is called and displayed on the display screen of FIG. 4A. is there. FIG. 5 is a diagram showing details of the diagnostic table window called up on the display screen of FIG.

Explanation of symbols

12 Transport Machine 14 Programmable Controller 16 Personal Computer

Claims (5)

  A first step for defining a process execution time required to execute the process for each control process for controlling the machine by a programmable controller, and a second step for setting a certain allowable time range for the process execution time according to the above definition And a third step of setting an abnormal condition in the process and a fourth step of setting an abnormality content corresponding to the abnormal condition for each control process. .   2. The process abnormal condition automatic extraction system according to claim 1, further comprising a fifth step of displaying at least an abnormality content corresponding to the control process.   2. The process abnormal condition automatic extraction method according to claim 1, wherein the execution results of the second to fourth steps are displayed on the display screen in the form of a diagnostic table.   2. The process abnormal condition automatic according to claim 1, wherein a first step that defines a preset process execution allowable error time and a process execution time is calculated, and an allowable time range of the second step is automatically set. Extraction method.   2. The process abnormality condition according to claim 1, wherein the first step is automatically performed based on the condition of the second step and the actual operation of the controlled object, and the optimum process abnormality extraction condition is automatically generated. Automatic extraction method.

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