JP2000250610A - Sequence control device and method and recording medium recording sequence control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To change a sequence program under execution into a received new sequence program without stopping the former sequence program, to output a control signal to every electric device included in the facilities on the basis of the sequence program under execution and to secure the optimum operation of every electric device by inputting the signals received from the electric devices. SOLUTION: This sequence control device is provided with a program reception part 1 to receive a sequence program from the outside and a work memory 2 which stores the sequence program received at the part 1 and a program transfer part 3 which decides the operating state of a program execution part 6 when the received sequence program is stored in the memory 2 and then transfers the sequence program to the bank of an execution program memory group 4 or 5 from the memory 2 while the part 6 is kept stationary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sequence control device for sequentially controlling and operating a plurality of electric devices in a facility including an assembly facility and a transport facility in a predetermined order.
The present invention relates to a sequence control method and a recording medium on which a sequence control program is recorded.

[0002]

2. Description of the Related Art In recent years, in a facility including an assembling facility and a transport facility, a plurality of electric devices requiring input / output control and numerical control are arranged, and these electric devices are sequentially operated based on the use of the facility. A sequence control device for performing the operation is provided. That is, in such equipment, the sequence controller uses a sequence program (ladder program) corresponding to the control specification of the equipment, and various switches, sensors, cameras, relays, valves, LEDs, lamps, motors, and the like in the equipment. Controlling electrical equipment. In such a sequence control device, a stored program method in which a sequence program received from the outside is stored in a memory (hereinafter, referred to as “execution program memory”) is often used. In order to execute the above-mentioned sequence program at high speed, the sequence control device generally uses a dedicated IC as its execution means. The necessary parts of the sequence program are sequentially read out from the execution program memory and executed. I do. Further, in the above-described sequence control device of the stored program method, one of the features is that the sequence program stored in the execution program memory can be changed at any time in response to a change in equipment specifications or addition of a function. In a conventional sequence control device, a new sequence program is changed by the following method.

In a conventional sequence control device having only one execution program memory, the execution of an existing sequence program stored in the execution program memory is stopped and then a new sequence program received from the outside is received. The program was stored in the program memory for execution. As a result, in the conventional sequence control device, a new sequence program is changed on the execution program memory. Also, in order to cope with the case where the change to the new sequence program is interrupted,
A conventional sequence control device having two execution program memories is known. In other words, in this conventional sequence control device, one execution program memory is reserved as a reception memory until all the new sequence programs are received, so that when the change of the new sequence program is interrupted, In response, a new sequence program was changed.

Here, a conventional sequence control device having two execution program memories will be specifically described with reference to FIG. FIG. 4 is a block diagram showing a configuration of a conventional sequence control device. As shown in FIG. 4, a conventional sequence control device 50 includes a program receiving unit 51 for receiving a sequence program from the outside, and two execution program memories 52 connected to the program receiving unit 51 via a switch 51a. , 53, and a program receiving unit 51 and a program executing unit 54 connected to the switch 51a. Program receiving unit 5
Reference numeral 1 denotes a dedicated IC configured to receive a new sequence program from outside. Program receiving unit 51
Stops the operation of the program execution unit 54 when a new sequence program is received,
a. The program receiving unit 51 includes a switch 51
a one of the execution program memories 5 connected through a
The new sequence program received is output and stored in 2, 53. When all the received sequence programs are output, the program receiving unit 51 activates the program executing unit 54.

The execution program memories 52 and 53 respectively constitute banks 1 and 2 which can input and output data independently of each other, and store and hold a sequence program from the program receiving section 51. The program execution unit 54 is configured by a dedicated IC, and is connected to a plurality of electric devices (not shown) in the facility controlled by the sequence control device 50. The program execution unit 54 reads a sequence program from one of the execution program memories 52 and 53 connected via the switch 51a, inputs a signal from each electric device (for example, a sensor) based on the sequence program, and It outputs a control signal for operating each electric device (for example, an LED or a relay). The input signal data (result information) is output from the program execution unit 54 to a memory (not shown) and held, and is reflected in the sequence program when the program execution unit 54 next executes the sequence program. That is, the program execution unit 54
Generates a control signal using the result information obtained by executing the previous sequence program, and outputs the control signal to each electric device.

The above-described conventional sequence controller 50 operates as follows. In the following description, the operation performed when the program receiving unit 51 receives a new sequence program from outside while the program executing unit 54 is executing the sequence program stored in the execution program memory 52 of the bank 1 is described. Will be described as an example. When the program receiving unit 51 receives a new sequence program from outside, the program receiving unit 51 stops the operation of the program executing unit 54. Then, the program receiving unit 5
1 operates the switch 51a to switch from the execution program memory 52 of the bank 1 to the execution program memory 53 of the bank 2. Then, the program receiving unit 51
Switches the received new sequence program to switch 5.
The program is output to the execution program memory 53 via 1a and stored. Subsequently, when all the received new sequence programs are output to the execution program memory 53, the program receiving unit 51 activates the program execution unit 54 to execute the new sequence programs. As described above, in the conventional sequence control device 50, when the program receiving unit 51 receives a new sequence program, the operation of the program execution unit 54 is stopped, the switch 51a is operated, and one of the execution program memories 52 , 53 as memory for reception. Thus, in the conventional sequence control device 50, the program execution unit 54
Was changed to a new sequence program without erasing the existing sequence program.

[0007]

In the conventional sequence control apparatus as described above, even if the sequence control apparatus has two execution program memories, the operation of the program execution unit is performed while a new sequence program is being received. Had stopped.
For this reason, the conventional sequence control device cannot output a control signal to each electric device in the facility while receiving a new sequence program, and can operate each electric device optimally. There was a problem that it was not possible. Further, the conventional sequence control apparatus has a problem in that it is not possible to input a signal from each electric device and reflect the data (result information) when executing the next sequence program. Specifically, for example, when a conventional sequence control device is used for a transport facility, the conventional sequence control device communicates with each electric device in the transport facility while receiving a new sequence program. Since signals cannot be input and output, there is a risk that the number of conveyed objects may be incorrectly counted, and necessary processing may not be performed correctly on the conveyed objects due to the count error. As described above, in the conventional sequence control device, when changing to a new sequence program, the operation or function of each electric device in the facility may be affected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is possible to change a received sequence program to a new sequence program without stopping the running sequence program. Sequence control device and sequence control that can output control signals to each electrical device in the facility according to the running sequence program and input signals from each electrical device to optimally operate each electrical device in the facility It is an object of the present invention to provide a recording medium recording a method and a sequence control program.

[0009]

According to the present invention, there is provided a sequence control apparatus comprising: an execution program memory group comprising at least two banks; and a program execution unit for executing a sequence program stored in the banks of the execution program memory group. A program receiving unit that receives a sequence program from the outside, a working memory that stores the sequence program received by the program receiving unit, and the sequence program that is received in the working memory. Is stored, the operation state of the program execution unit is determined, and the received sequence from the working memory to one bank of the execution program memory group is determined while the program execution unit is stopped. Program transfer unit that performs program transfer processing It is provided. With this configuration, the currently executed sequence program can be changed to the received new sequence program without stopping, and the control signal to each electric device in the equipment can be changed by the currently executed sequence program. And output
By inputting a signal from each electric device, each electric device in the facility can be operated optimally.

A sequence control method according to the present invention is a sequence control method for executing a sequence program stored in each bank of an execution program memory group including at least two banks. A storage step of storing the sequence program received in the receiving step in a working memory; a determination step of determining an operation state of the program execution unit when the received sequence program is stored in the storage step; A transfer step of transferring the received sequence program from the working memory to one bank of the execution program memory group while the program execution unit determined in the step is in a halt state. With this configuration, the currently executed sequence program can be changed to the received new sequence program without stopping, and the control signal to each electric device in the equipment can be changed by the currently executed sequence program. Is output, and signals from the respective electrical devices are input to allow the respective electrical devices in the facility to operate optimally.

A recording medium on which the sequence control program of the present invention is recorded receives a sequence program from the outside, stores the received sequence program in a work memory, and executes the program when the received sequence program is stored. Determining the operation state of the section, and transferring the sequence program from the working memory to one bank of the execution program memory group while the determined program execution section is in the stopped state. With this configuration,
Without stopping the running sequence program, it is possible to change to the received new sequence program, and thus output a control signal to each electric device in the facility according to the running sequence program, and from each electric device, , Each electrical device in the facility can be operated optimally.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments showing a sequence control apparatus and a sequence control method according to the present invention will be described below with reference to the drawings. In the following description, an embodiment having a configuration in which two execution program memories are provided as in the above-described conventional example will be described in order to facilitate comparison with the conventional example.

Embodiment FIG. 1 is a block diagram showing a configuration of a sequence control device according to an embodiment of the present invention. As shown in FIG. 1, the sequence control device 10 of the present embodiment
Is a program receiving unit 1 for receiving a sequence program from the outside, a working memory 2 and a program transferring unit 3 connected to the program receiving unit 1, and two program connecting units 3 connected to the program transferring unit 3 via a switch 3a. Execution program memories 4 and 5 are provided. Further, the sequence control device 10 includes a program transfer unit 3 and a switch 3
a, and a cycle end processing unit 7 connected to the program execution unit 6. Note that the sequence control device 10 of the present embodiment
Are connected to a plurality of electric devices in the equipment to be controlled (not shown). Further, the sequence control device 10 of the present embodiment performs a batch input / output scan in which the sequence program execution processing by the program execution unit 6 and the cycle end processing by the cycle end processing unit 7 are repeated in this order and as one cycle. It is of the system. The specific time required for one execution processing and cycle end processing is, for example, 800 μs and 200 μs, respectively.
μs, and the sequence control device 10 repeats the operation of one cycle in a processing time of 1 ms in total.

The program receiving section 1 is preferably a CPU
And receives a new sequence program from the outside and stores it in the working memory 2.
All received sequence programs are stored in the working memory 2
, The program receiving unit 1 notifies the program transfer unit 3 that the receiving process of the sequence program has been completed. This reception processing is performed independently of the execution processing of the sequence program in the subsequent program execution unit 6. If the received sequence program is composed of an intermediate code that cannot be executed by the subsequent program execution unit 6, the program reception unit 1 translates and converts the sequence program into an execution code that can be executed by the program execution unit 6, Output to the working memory 2. The work memory 2 is configured by a memory having a storage capacity of, for example, 256 Kbytes.

When the program transfer unit 3 is notified by the program reception unit 1 that the reception processing of the sequence program has been completed, the program transfer unit 3 determines the operation state of the program execution unit 6. The program transfer unit 3 operates the switch 3a while the program execution unit 6 is in the stopped state, and transfers a new sequence program stored in the working memory 2 to one of the execution sequences connected via the switch 3a. The data is transferred to the program memories 4 and 5. In addition, in the stop state here,
This includes a stop state in which the program execution unit 6 has completed one execution of the sequence program and stopped during the cycle end processing performed subsequent to the execution processing. That is, when the sequence control device 10 is operating, the program transfer unit 3 detects while the program execution unit 6 is in the stop state, and generates a new sequence within the cycle end processing time while the program execution unit 6 is in the stop state. Performs program transfer processing. Specifically, the program transfer unit 3 executes a transfer processing time set in advance (for example, 18
A new sequence program of a predetermined size that can be transferred in 0 μs) is transferred from the work memory 2 to one of the execution program memories 4 and 5.

More specifically, if the data size of the new sequence program is smaller than the predetermined size and all the sequence programs can be transferred in one transfer process,
After finishing the transfer process, the program transfer unit 3 does not operate the switch 3a and does not switch the execution program memories 4 and 5. Thereby, the program execution unit 6
When executing the next execution process, a new sequence program stored and changed in one of the execution program memories 4 and 5 can be executed. On the other hand, if the data size of the new sequence program is
If all the sequence programs cannot be transferred in one transfer process, the program transfer unit 3 divides the new sequence program into blocks having a predetermined size, and transfers the one block program except when the transfer process of the last block is completed. The switch 3a is operated every time the transfer process of
The program memory is switched from one of the transfer destination execution program memories 4 and 5 to the other. Accordingly, even when a new sequence program cannot be transferred within the cycle end processing time, the new sequence program can be transferred and changed without stopping the sequence program being executed by the program execution unit 6. . That is,
Until the program transfer unit 3 completely stores a new sequence program in one of the execution program memories 4 and 5, the program execution unit 6 executes the existing sequence stored in the other execution program memories 4 and 5. The program can be executed continuously.

As described above, in the sequence control device 10 of the present embodiment, the program transfer unit 3
Is determined, and the transfer process is performed while the program execution unit 6 is in the stopped state. Thus, in the sequence control device 10 of the present embodiment, even if the program execution unit 6 is executing a sequence program, the sequence program being executed can be changed to a new sequence program without stopping. it can. In the above description, the configuration in which the program transfer unit 3 performs the transfer process of the predetermined size so that the transfer process can be performed within the cycle end processing time has been described.
The program transfer unit 3 may calculate and determine the size to be transferred in one transfer process based on the transfer capability and perform the transfer process within the cycle end processing time. The transfer capability described above is defined by the transfer speed of the program transfer unit 3 including the data read speed in the working memory 2 and the data write speed in the execution program memories 4 and 5.

The execution program memories 4 and 5 respectively constitute banks 1 and 2 that can input and output data independently of each other, and form an execution program memory group including the banks 1 and 2. In this execution program memory group, one bank always has the program transfer unit 3
And is connected to the switch 3a. Each of the execution program memories 4 and 5 has, for example, 128
It is composed of a memory having a Kbyte storage capacity, and stores and holds a sequence program from the program transfer unit 3. The program execution unit 6 is preferably constituted by an IC including a CPU, and reads out a sequence program from one of the execution program memories 4 and 5 connected via the switch 3a. The program execution unit 6 executes the read sequence program to generate a control signal for operating each electric device. The generated control signal is transmitted to the program execution unit 6 and the cycle end processing unit 7.
And is temporarily stored in a memory (not shown) provided between them. The memory stores result information data indicating operation results obtained by executing the previous sequence program, and the program execution unit 6 can reflect the result information data in the sequence program. . It should be noted that specific examples of the result information include information indicating a lighting state of an LED included in the above-described electric device and an ON / OFF state of a valve. The cycle end processing unit 7 performs a predetermined cycle end process including input / output processing of the control signal and the signal with each of the external electric devices. For details,
The cycle end processing unit 7 reads the control signal generated by the program execution unit 6 from the memory, and outputs the control signal to a corresponding electric device. The cycle end processing unit 7 receives a signal from each electric device and stores the signal in the memory.

Hereinafter, the operation of the sequence control apparatus according to the present embodiment will be described with reference to FIGS. In the following description, the operation when the program receiving unit 1 receives a new sequence program from outside while the program executing unit 6 is executing the sequence program stored in the execution program memory 4 of the bank 1 is described. Will be described as an example. FIG. 2 is a flowchart showing the operation of the sequence control device shown in FIG. As shown in FIG.
In the sequence control device 10 of this embodiment, when the program receiving unit 1 receives a new sequence program, the program receiving unit 1 stores the received program in the working memory 2 (Step S1). Then, the program receiving unit 1 determines whether or not all of the new sequence programs have been received (step S2). If the reception of all the sequence programs has been completed, the program receiving unit 1 terminates the reception processing. The program transfer unit 3 is notified of the fact.

Subsequently, when the program transfer unit 3 is notified that the reception process has been completed, the program transfer unit 3 determines the operation state of the program execution unit 6 and determines whether the program execution unit 6 is in the stopped state. Determine whether or not. That is, the program transfer unit 3 determines whether or not one execution of the sequence program has been completed (step S3). If the execution has been completed, the program transfer unit 3 sets the switch 3a to OFF. Works,
Switching from the execution program memory 4 of the bank 1 to the execution program memory 5 of the bank 2 (step S
4). Thereafter, the program transfer unit 3 transfers the sequence program from the working memory 2 to the execution program memory 5.
A new sequence program is transferred (step S5). At this time, if the data size of the new sequence program is larger than the predetermined size, the program transfer unit 3 sets a new time so that the transfer process is completed within the cycle end processing time of the cycle end processing unit 7 that is being executed simultaneously. After a simple sequence program is divided into blocks having a predetermined size, transfer processing is performed.

Next, the program transfer unit 3 determines whether or not all the new sequence programs have been transferred (step S6). If all of the sequence programs have been transferred, the program transfer unit 3 determines the operation. finish. On the other hand, if all of the sequence programs have not been transferred, the program transfer unit 3 operates the switch 3a to execute the execution program memory 5 of the bank 2.
Is switched to the execution program memory 4 of the bank 1 (step S7). Then, the program transfer unit 3 notifies the cycle end processing unit 7 that the bank has been switched to the original bank. After the cycle end processing unit 7 completes the predetermined cycle end processing, the cycle end processing unit 7 6 is started (step S8). Subsequently, the program transfer unit 3 returns to step S3 and performs the operation shown in step S3.

In the above description, the case where the transfer process and the cycle end process are performed at the same time has been described, but the embodiment is not limited to this. For example, the transfer processing and the cycle end processing can be realized by software functions and further configured to be executed by one CPU, thereby simplifying the configuration of the sequence control device. In the case where the processing is performed by one CPU as described above, the transfer processing and the cycle end processing cannot be performed simultaneously. Therefore, as shown in FIG. 3, for example, after the CPU determines whether or not one execution of the sequence program has been completed, the CPU first performs a cycle end process (step S9), and then performs a transfer process. What is necessary is just to comprise. Further, the order of the cycle end process and the transfer process can be switched. Specifically, step S7 and step S7 in FIG.
The cycle end process shown in step S9 described above may be configured to be performed between the end of the cycle. In the case where the processing is performed by one CPU as described above, it is preferable that the transfer processing time is shorter than the above-described execution processing time and cycle end processing time. Specifically, when the execution processing time and the cycle end processing time are 800 μs and 200 μs, respectively, the transfer processing time is preferably 10 μs or less. Thereby, the influence of the transfer process on the execution process and the cycle end process can be significantly suppressed.

As described above, in the sequence control device 10 and the sequence control method of the present embodiment, the working memory 2 stores the new sequence program received by the program receiving unit 1, and the storage (reception processing) is performed. When the operation is completed, the program transfer unit 3 determines the operation state of the program execution unit 6. Furthermore, in the sequence control device 10 and the sequence control method according to the present embodiment, the program transfer unit 3 transfers the data from the working memory 2 to one of the execution program memories 4 and 5 while the program execution unit 6 is stopped. It is configured to perform transfer processing of a new sequence program. As a result, in the sequence control device 10 and the sequence control method of the present embodiment, the sequence program being executed by the program execution unit 6 can be changed to a new sequence program without stopping. Therefore, the sequence control device 10 of the present embodiment,
In the sequence control method, a control signal to each electric device in the facility is output according to the sequence program being executed, and a signal from each electric device is input so that each electric device in the facility can operate optimally. .

In the above description, the configuration using the execution program memory group consisting of two banks has been described. However, the number of banks in the execution program memory group is not limited to two. An execution program memory group including one or more banks may be used. In such a configuration, the program transfer unit may select one bank not used for execution by the program execution unit and transfer a new sequence program to the selected bank. Further, as a method of selecting a transfer destination bank, there is a method instructed by an operator or the like, or a method of automatically detecting and selecting a bank in which the oldest sequence program is stored.

In addition to the above description, the working memory can be configured by using a memory having a smaller storage capacity than each bank of the execution program memory group. With this configuration, it is assumed that the working memory becomes full during the reception of a new sequence program.
For this reason, it is preferable that the program receiving unit requests the program transfer unit to perform a transfer process according to the state of the working memory and operates the switch. That is, when the working memory becomes full during the reception of a new sequence program, the program reception unit outputs a transfer request to the program transfer unit with the condition that the reception is being performed.
Further, it is preferable that the program transfer unit is configured to operate the switch even after the transfer of the last block divided into a predetermined size to switch to the original bank of the execution program memory. Further, since any of the sequence control methods in the above-described embodiments can be computer-programmed, a computer-executable recording medium can provide the sequence control method of the present application. Here, the recording medium is a data recording device including a floppy disk, a CD-ROM, a DVD, a magneto-optical disk, a removable hard disk, and a flash memory.

[0026]

As described above, according to the sequence control device and the sequence control method of the present invention, the working memory stores the new sequence program received by the program receiving unit, and transfers the program when the receiving process is completed. The unit determines an operation state of the program execution unit. further,
In the sequence control device and the sequence control method according to the present invention, the program transfer unit performs a process of transferring a new sequence program from the working memory to one bank of the execution program memory group while the program execution unit is in the stop state. It is configured to do so. Thus, in the sequence control device and the sequence control method of the present invention, the sequence program being executed by the program execution unit can be changed to a new sequence program without stopping. Therefore, in the sequence control device and the sequence control method of the present invention, a control signal to each electric device in the facility is output according to the sequence program being executed, and a signal from each electric device is input to each electric device in the facility. Equipment can operate optimally. Further, since the sequence control method of the present invention can be made into a computer program, the above-described sequence control can be performed by recording the sequence control method of the present invention on a computer-readable recording medium.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a sequence control device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the sequence control device shown in FIG. 1;

FIG. 3 is a flowchart showing an operation of a modification of the sequence control device shown in FIG. 1;

FIG. 4 is a block diagram showing a configuration of a conventional sequence control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Program receiving part 2 Working memory 3 Program transfer part 4,5 Execution program memory 6 Program execution part 7 Cycle end processing part 10 Sequence control device

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H219 AA07 CC10 CC11 EE05 HH25 HH28 5H220 BB09 BB12 CC05 CX02 CX04 EE08 EE19 JJ13 JJ16 JJ24 JJ29

Claims (4)

[Claims] 1. A sequence control device comprising: an execution program memory group including at least two banks; and a program execution unit that executes a sequence program stored in a bank of the execution program memory group. A program receiving unit that receives a sequence program from the outside, a working memory that stores the sequence program received by the program receiving unit, and an operation of the program executing unit when the received sequence program is stored in the working memory. A program transfer unit for determining a state and performing a transfer process of the received sequence program from the working memory to one bank of the execution program memory group while the program execution unit is in a stop state. Sequence control device characterized by performing Place. 2. A cycle end processing unit for performing a predetermined cycle end process including a process of inputting / outputting a signal to / from an electric device to be controlled each time execution of a sequence program by the program execution unit is completed once. The sequence control device according to claim 1, wherein the program transfer unit is configured to perform the transfer process within a cycle end processing time of the cycle end processing unit. 3. A sequence control method for executing a sequence program stored in each bank of an execution program memory group including at least two banks, wherein: a receiving step of receiving a sequence program from the outside; A storage step of storing the received sequence program in a working memory; a determination step of determining an operation state of the program execution unit when the received sequence program is stored in the storage step; and the program determined in the determination step A transfer step of transferring the received sequence program from the working memory to one bank of the execution program memory group while the execution unit is stopped. Method. 4. Receiving a sequence program from the outside, storing the received sequence program in a working memory, determining an operation state of a program execution unit when the received sequence program is stored, Transferring the sequence program from the working memory to one bank of the execution program memory group while the program execution unit is stopped.