JPS63269202A - Monitoring method for sequence program control system - Google Patents

Abstract

PURPOSE:To easily cope with the change of an equipment to be controlled by monitoring each operation of this equipment based on an abnormality decision signal obtained from a monitor controller. CONSTITUTION:A monitor controller 100 takes in data Dx, which corresponds to respective operation states of a carrying machine 12, a clamping device 14, working machines 16A and 16B, and working machine driving parts 18A and 18B indicated by a signal Sx, from a controller 50 for driving control at a prescribed period. Based on taken-in data Dx, it is discriminated whether the operation of each device accords with the transition order, the allowable time, and the precedence stored in an incorporated memory or not. If it does not accord with them, an abnormality display signal Cg is supplied to a display device 90 and data Dy for countermeasure against abnormality is supplied to the controller 50. Then, the operation of each device is stopped and the abnormality is located in accordance with contents displayed on the display device 90 to take a countermeasure against the abnormality.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for monitoring a sequence program control system for monitoring a series of operations in a controlled facility whose operations are controlled according to a sequence program.

(Prior Art) In a controlled facility whose operation is controlled according to a sequence program, it is necessary to monitor whether or not the devices constituting the facility are operating properly according to the sequence program. Therefore, as a conventional method for monitoring a series of operations in controlled equipment, for example, limit switches that switch on and off states in conjunction with the forward or backward movement of devices are placed in the controlled equipment. , a time monitoring circuit unit is prepared that determines whether the time required for each operation is appropriate based on the signal obtained from the limit switch, etc., and an abnormality determination signal obtained from the time monitoring circuit unit is used. Based on the above, there is a method for monitoring each operation in controlled equipment, or a method for monitoring two limit switches that are arranged so that they are not in the on state at the same time when normal operation is being performed. A contradiction determination circuit unit is provided that determines whether a contradiction that cannot occur during normal operation has occurred, such as whether the Methods of monitoring each operation are known.

However, the above-mentioned monitoring method that uses a time monitoring circuit, a contradiction discriminating circuit, etc. is difficult to apply to complex and large-scale controlled equipment, and it is difficult to apply the monitoring method to controlled maintenance. Even if there is a change, it is often not possible to easily change the dedicated circuit section in response to the change.

In addition, as an alternative method to the above method, a so-called step-by-step sequence program is created so that the transition order of each operation in the controlled equipment is constant, and according to this sequence program, the transition order of each operation in the controlled equipment is constant. A method has been considered that controls the operations and monitors whether the transition order of each operation follows a sequence program.

(Problem to be Solved by the Invention) However, in controlled equipment that is usually composed of a large number of devices, certain operations in one device are duplicated in certain operations in other devices. Since they are often performed simultaneously, it is possible to create a sequence program that causes each operation of the controlled equipment to be performed in a fixed order.
This is only applicable to extremely limited controlled equipment, and the practical range of the above method is extremely narrow. Furthermore, it is not preferable to create a step-by-step sequence program without simultaneous operations from the viewpoint of efficient operation of the controlled equipment.

In view of these points, the present invention is designed to be able to easily respond to changes in the controlled equipment, and to expand the scope of practical use without hindering the efficient operation of the controlled equipment. Another purpose of this invention is to provide a method for monitoring a sequence program control system.

(Means for Solving the Problems) In order to achieve the above-mentioned object, a method for monitoring a sequence program control system according to the present invention is divided into a plurality of independent operation groups in which the transition order of each operation is constant, A transition order of each operation in each of the independent operation groups, a transition condition of each operation in each of the plurality of independent operation groups, and a plurality of independent operation groups in a controlled equipment whose operation is controlled according to a predetermined sequence program. A plurality of independent motion groups is stored based on the stored transition order, transition conditions, and precedence relationships. A monitor controller is provided that determines whether or not there is an abnormality in each operation in each of the independent operation groups, and generates an abnormality determination signal depending on the presence or absence of the above-mentioned abnormality. Each operation in the controlled equipment is monitored based on the abnormality determination signal.

(Function) When a method for monitoring a sequence program control system having the above-mentioned configuration is adopted, the monitoring controller detects whether or not there is an abnormality in each operation of each of a plurality of independent operation groups in the controlled equipment. of,
Since each independent action group is discriminated individually, each action can be properly monitored even in controlled equipment where a certain action in one independent action group and a certain action in another independent action group are performed at the same time. will be held. Furthermore, even if the operation mode of devices constituting one independent operation group is changed and the transition conditions of each operation in the independent operation group are changed, the transition conditions of each operation in the other independent operation groups stored in the storage means are changed. Since there is almost no need to change the operation transition conditions, it is possible to easily respond to changes in the controlled equipment.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows controlled equipment to which an example of a method for monitoring a sequence program control system according to the present invention is applied.

The controlled equipment shown in FIG. 1 includes a transport machine 12. A clamp device 14 that clamps the work 10 transported to the second station ST, two processing machines 16A and 16B that perform processing such as drilling on both sides of the work 10 clamped by the clamp device 14, and This processing machine 16
A processing machine drive section 18A that drives A and 16B forward to the processing position and drives them backward from the processing position to the original position.
It consists of devices such as and 18B.

Furthermore, although not shown, in the area indicated by the two-dot chain line in FIG. Various signals Sx indicating the operating status of each device are supplied to the drive controller 50. Based on the signal Sx, the drive control controller 50 generates control signals Ca, Cb, Cc, Cd, and C according to a sequence program determined in advance and stored in the built-in memory.
e and Cf are formed and transferred to a conveyor 12 and a clamp device 14. It is supplied to processing machines 16A and 16B1 and processing machine drive units 18A and 18B.

As a result, the conveyor"2. The clamp device 14 and the processing machine drive units 18A and 18B each perform operations according to a sequence program, with the range indicated by the dashed lines A, B, C, and D in FIG. 2 as one cycle. That is, when the transport IT2 is supplied with the control signal Ca that instructs the start, it performs an upward movement and receives and picks up the workpiece 10 placed on the receiving jig arranged at the first station ST. , and then performs a forward movement to transport the workpiece 10 to the second station ST2, and then performs a downward movement to transport the workpiece 10 to the receiving jig disposed at the second station ST. Thereafter, it performs a backward movement to return to its original state, and waits in its original state until a control signal Ca is supplied to issue a start command. When the conveyor 12 is in operation, the drive controller 50 uses a signal S supplied from the detection means to indicate that each of its upward movement, forward movement, downward movement, and backward movement has been completed.
Detect based on x. Then, when it is detected that the lowering operation of the carrier 12 is completed, a control signal cb for issuing a start command is supplied to the clamp device 14. Therefore,
The carrier 12 will generate a timing signal to start the clamp device 14 at the completion of the lowering operation. Note that the timing signal for starting the transport machine 12 is generated by, for example, a workpiece feeding device that places the workpiece 10 on a receiving jig at the first station STI.

The clamping device 14 receives a control signal cb that generates a start command.
When the workpiece 10 is supplied, the workpiece 10 placed on the receiving jig at the second station ST2 is clamped, and when this clamping operation is completed, the processing machine drive unit Generates a timing signal to start 18A and 18B, then works 1
When the control signal cb that holds the clamped state of 0 and issues a return command is supplied, the workpiece 10 is unclamped and returned to its original state, and the control signal cb that issues a start command is supplied. Wait in front of the original condition until

In addition, when the processing machine drive units 18A and 18B are supplied with control signals Ce and Cf that issue a start command, respectively, they drive the processing machines 16A and 16B forward, respectively.
When the processing machines 16A and 16B reach the processing position, the forward drive is stopped, and when the control signals Ce and Cr are supplied to issue a return command, the processing machines 16A and 16B are driven backward, and when the backward drive is completed, the clamping A timing signal is generated to cause the device 14 to perform a return operation, and then the device 14 waits in front of its original state. Note that the timing signal for causing the machining machines 116A and 16B to perform the backward movement is, for example, for the machining machines 16A and 16B whose operation is not shown in FIG.
is assumed to occur when the machining operation of the workpiece 1o is completed, and the clamp release operation in the clamp device 14 is performed after both the processing machine drive units 18A and 18B complete the backward drive. .

Under the control as described above, the conveyor 12, the clamp device 14. If the transition order of each operation in the processing machines 16A and 16B and the processing drive units 18A and 18B is constant, and there is no abnormality in the controlled equipment, the transfer machine 12, the clamp device 14. Processing machine 1
It is assumed that the time required for each operation in the processing drive units 6A and 16B and the processing drive units 18A and 18B does not change appreciably.

The conveyor 12 and the clamp device 14 are controlled as described above. In order to determine whether each operation in the processing machines 16A and 16B and the processing machine drive units 18A and 18B is being performed properly, the monitor controller 1
00 is provided.

The built-in memory of the monitor controller 100 stores information about the transport machine 12. when the operation is controlled by the drive controller 50 as described above. Clamp device 14. Processing machines 16A and 16B and processing machine drive units 18A and 18
Proper transition order of each operation in each of B, and allowable time for each operation.

The relationship between the start time of clamping in the clamp device 14 and the time of completion of the descending operation in the conveyor 12, and
The relationship between the time when the clamp device 14 completes clamping and the forward drive start time of the processing machine drive units 18A and 18B is stored in advance.

The monitor controller 100 controls the transport machine 12, clamp device 14, etc. to which the signal Sx is sent from the drive control controller 50. Data Dx corresponding to each operating state of the processing machines 16A and 16B and the processing machine drive units 18A and 18B
is captured at a predetermined period, and based on the captured data Dx, the transport machine 12. Clamp device 14. Processing machine 16A
and 16B, and the above-mentioned transition order in which each operation in the processing machine drive units 18A and 18B is stored in the built-in memory,
Conveyor 12. Clamp device 14. The processing machines 16A and 16B and the processing machine drives 18A and 18B (7) are individually determined, and if it is determined that they are not compatible, the display 9o will indicate the non-compatible operating state. In order to display the type of equipment and its operating state, an abnormality display signal Cg is supplied, and data [)y for abnormality countermeasures is supplied to the drive control controller 50. As a result, for example, the operation of each device is stopped, and the display 90
The location of the abnormality will be clarified from the content displayed, and countermeasures will be taken against the abnormality.

In this way, the transporting machine 12. Clamp device 14. Each operation in the processing machines 16A and 16B and the processing machine drive units 18A and 18B is
By individually monitoring each device, even if the controlled equipment is equipped with devices that operate simultaneously, such as the processing machine drive units 18A and 18B, the individual operations of each device can be controlled. You will be monitored.

In addition, even if there is a change in the operation mode of one device in the controlled equipment, there is no need to change the transition conditions such as the allowable time for each operation in other equipment, so each device in the controlled equipment Even if some changes are made to similar operations, it can be easily accommodated.

Monitor controller 100 that performs control as described above
is configured using, for example, a microcomputer, and an example of a program executed by the microcomputer in such a case will be explained with reference to the flowcharts of FIGS. 3 to 7.

FIG. 3 shows a routine for monitoring each operation in the conveyor 12, and after starting, the routine
Process 101 captures data Dx, and in subsequent decision 102, it is determined based on the data DX whether or not the lifting operation of the carrier 12 has started, and if it is determined that the lifting operation has not started, the original If it is determined that the ascending operation has started, the process proceeds to process 103. In the process 103, in order to monitor the upward movement of the conveyor 12, as shown in FIG. 4, which will be described later,
Execute a subroutine.

After starting, the subroutine shown in FIG. 4 subtracts 1 from a predetermined count Ta in process 111, sets it as a new count Ta, and runs process 111.
Proceed to step 2. In process 112, data Dx is taken in, and in subsequent decision 113, it is determined whether or not the lifting operation of the conveyor 12 has been completed based on the data Dx.If it is determined that the lifting operation has been completed, decision 114 It is determined whether the count number Ta exceeds a predetermined value T, and if it is determined that the count number Ta exceeds the value T1, the time required for the upward movement is longer than the permissible time specified for it. Since it is short, process 1
At step 16, the abnormality display signal Cg is supplied to the display 90, and data Dy is supplied to the drive control controller 50, and this program ends. Further, if it is determined in decision 113 that the rising operation is not completed, then in process 117 the count number Ta
If it is determined that the count number Ta is not zero, it returns to the original state, and if it is determined that the count number Ta is zero, the time required for the upward movement is determined. ,
Since the predetermined allowable time is exceeded, an abnormality display signal Cg is supplied to the display 90 in process 118, and data D is supplied to the drive control controller 50.
Supply y and return to process 112.

After this subroutine ends, in processes 105 and 106, the forward movement and the downward movement are monitored in the same manner as the above-mentioned upward movement, and in the following process 107, it is determined whether the downward movement has been completed. Hail flag F.

is set to 1, and then, in process 108, the backward movement is monitored in the same manner as the upward movement described above, and the process returns to the original state.

FIG. 5 shows a routine for monitoring each operation in the clamp device 14. After starting, this routine takes in a flag F in a process 121, and in a process 122 judges whether the flag F1 is 1 or not. However, if it is determined that flag F is not 1, the flag F returns to the original state.

If it is determined that is 1, the lowering operation of the conveyor 12 has been completed, so in process 123, 1-+t- is subtracted from the predetermined count number To, and it is set as the new count number Te. Then proceed to decision 124. In decision 124, it is determined whether or not the count number Te is zero. If it is determined that the count number Te is not zero, the process returns to process 123 and the count number Te
If it is determined that is zero, data Dx is fetched in process 125, and in decision 126, it is determined whether or not the clamping operation has been started based on the data Dx, and it is determined that the clamping operation has not been started. In this case, in process 127, the abnormality display signal Cg is supplied to the display 90, and the data Dx is supplied to the drive control controller 50, and the process returns to process 125, and in decision 126, it is determined that the clamping operation has started. In the case, in process 128,
The clamping operation is monitored in the same manner as the above-mentioned monitoring of the lifting operation in the conveyor 12, and in the subsequent process 129, the hail flag F2 is set to 1 to determine whether the clamping operation is completed, and then in the process 130. move on.

In the process 130, the processing machine drive unit 1, which will be described later,
A flag F3 is set in the routine for monitoring each operation in Step 8A, and indicates whether the backward drive operation of the processing machine drive section 18A has been completed. If it is determined that the flag F is not 1, the process returns to step 130, and if it is determined that the flag F3 is 1, the backward drive operation of the processing machine drive unit 18A is performed. Since the process has been completed, the process proceeds to process 132, where the backward driving operation of the processing machine drive unit 18A, which is set in the routine for monitoring each operation in the processing machine drive unit 18B, has been completed. The flag F4 is fetched, and in the subsequent decision 133 it is determined whether or not the flag F4 is 1. If it is determined that the flag F4 is not 1, the process returns to process 132 and it is determined that the flag F4 is 1. If so, proceed to process 134.

In process 134, similar to processes 125 to 127, the start of the clamp release operation is monitored,
In the following process 135, the unclamping operation is monitored in the same way as the clamping operation described above, and then process 1
At step 36, flags Ft, Fz and F4 are set to zero and the process returns to the original state.

FIG. 6 shows a routine for monitoring each operation in the processing machine drive unit 18A. After the start, this routine takes in the flag F2 in a process 141, and in the subsequent decision 142, determines whether the flag F2 is 1 or not. If it is determined that the flag F2 is not 1, the process returns to the original state, and if it is determined that the flag F2 is 1, the operation in the clamp device 14 described above is sequentially performed in processes 143 and 144. Similarly to the monitoring of
Process 1 by monitoring the forward drive start and forward drive operation.
Proceed to step 45.

In the process 145, the data Dx is taken in, and in the subsequent decision 146, it is determined whether or not the machining operation of the workpiece 10 by the processing machine 16A is completed.If it is determined that the machining operation is not completed, the process 14
Returning to step 5, if it is determined that the machining operation is complete, in processes 147 and 148, the start of the backward drive and the backward drive operation are sequentially monitored in the same manner as the operation of the clamp device 14 described above. and process 149
The program then proceeds to set the aforementioned flag F3 to 1 and returns to the previous step.

Note that the routine for monitoring each operation in the processing machine drive section 18B is substantially the same as the routine for monitoring each operation in the processing machine drive section 18A described above, so the flowchart is shown in the seventh section. It is shown in the figure and its detailed explanation will be omitted.

(Effects of the Invention) As is clear from the above description, the method for monitoring a sequence program control system according to the present invention allows the monitoring controller to detect abnormalities in each operation in each of a plurality of independent operation groups in the controlled equipment. is determined individually for each independent action group, and even in controlled equipment where a certain action in one independent action group and a certain action in another independent action group are performed simultaneously, each action can be properly monitored. can be done,
The scope of practical use can be expanded without hindering effective operation of controlled equipment. Furthermore, even if there is a change in the operation mode of devices constituting one independent operation group and the transition conditions of each operation in the independent operation group are changed, the transition conditions of each operation in the independent operation group stored in the storage means will be changed. Since there is almost no need to change the transition conditions of each operation, it is possible to easily respond to changes in the controlled equipment.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing a controlled equipment to which an example of the method for monitoring a sequence program control system according to the present invention is applied, and FIG. 2 is provided to explain the operation of the controlled equipment shown in FIG. 1. 3 to 7 are flowcharts showing an example of a program executed by a microcomputer when the microcomputer is used as the monitor controller shown in FIG. 1. In the figure, 10 is a workpiece, 12 is a conveyor, 14 is a clamp device, 16A and 16B are processing machines, 18A and 18B are processing machine drive units, 50 is a drive control controller, 90 is a display, and 100 is a monitor controller It is.

Claims (1)

[Claims] A transition order of each operation in each of the independent operation groups in a controlled equipment that is divided into a plurality of independent operation groups in which the transition order of each operation is constant and whose operation is controlled according to a predetermined sequence program; A transition condition for each motion in each of the plurality of independent motion groups, and a successor relationship of a specific motion in another independent motion group to a specific motion in one of the plurality of independent motion groups are stored. At the same time, based on the stored transition order, transition conditions, and successor relationship, the presence or absence of an abnormality for each operation in each of the plurality of independent operation groups is individually determined for each independent operation group, and the abnormality is determined for each independent operation group. Sequence program control characterized in that a monitoring controller that generates an abnormality determination signal depending on the presence or absence is prepared, and each operation in the controlled equipment is monitored based on the abnormality determination signal obtained from the monitoring controller. How to monitor the system.