JP3426405B2 - Sequence program creation device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sequence program creating apparatus, and more specifically, to creating a sequence program for converting a sequence control model input using a Petri net on a screen into a sequence program of a predetermined format and displaying the sequence program. It relates to the device.

[0002]

2. Description of the Related Art Conventionally, ladder diagrams have been widely used in the development of sequencer programs for sequence control. This is for turning on / off the operating conditions of individual devices.
It is described by a combination of F information, and is generally used even now. However, in this ladder diagram, it is difficult to see the overall control flow only by listing individual conditions, and the program is difficult for the person who created it to understand. Therefore, problems such as poor maintainability have been pointed out. Against this background, several attempts have recently been made to use Petri nets for creating sequence programs. For example, in Japanese Unexamined Patent Publication No. 4-18605, operation specifications of a machine are divided into an operation flow and an operation specification. The operation flow in this is expressed by a Petri net, and the operation specification is expressed by a sequence table, and then both are combined. The method of converting to a ladder format sequence program and displaying it is introduced.

[0003]

In the conventional method as described above, since the place of the Petri net expresses only the operation of the machine, the flow of the operation can be expressed on the Petri net. The state of the controlled device, such as the state of, and various other conditions for operating the machine (abnormal condition, state of input / output devices such as sensors) cannot be expressed on the Petri net. Therefore, it is difficult to visually understand the flow of control in terms of creating a program. In addition, since the Petri net and the sequence table are independent and separate, it is inconvenient because the operation specifications of each place cannot be seen on the Petri net editor. Furthermore, since the conventional ladder diagram and Petri net do not correspond well, the ladder program generated by the conversion is far from the one created by humans, and it tends to be difficult to decipher. The present invention has been made in view of the above circumstances, and an object of the present invention is to visually represent the control flow and the state of each device by making the best use of the advantage that the control flow of a Petri net is easy to see. However, it is still another object of the present invention to provide a sequence program creation device in a form that fully incorporates the characteristics of conventional ladder programming.

[0004]

According to a first aspect of the invention to achieve the above object, converting and displaying the sequence control model that is input with Petri nets on screen in a predetermined format sequence program In a sequence program creation device, a sequence control model input using an extended Petri net that expands the above Petri net to include multiple types of places and multiple types of arcs to realize the functions required for sequence control. And a second model storage unit for storing, and a condition input in the form of a logical expression for each place so that the state of each place included in the extended Petri net is established, and setting information necessary for each place. A second condition storage means, and an automatic operation based on the sequence control model and the condition and setting information stored above. And it is configured to extend conditions made as a sequence program creating device, characterized by comprising and a second sequence program display means for displaying converted into a predetermined format sequence program.

[0005] Further, the second model storing means,
A state place showing the control state of the target device of the sequence control, a time place showing the timer function of the sequencer performing the sequence control, a counter place showing the counter function of the sequencer performing the sequence control, an output showing the output from the sequencer. Input using an extended Petri net that includes all or part of a place, an arithmetic place indicating various arithmetic functions of the above sequencer, an input place indicating input to the above sequencer, and a reference place referencing on / off information of other places The sequence program creating device is characterized by storing the created sequence control model.

Further, the second model storage means is
A sequence program creating device characterized by storing a sequence control model input using an extended petri net including hierarchical places that hierarchically describe a petri net. Further, the second model storage means has an a-contact connecting arc that represents the a-contact connection of the sequencer, a b-contact connecting arc that represents the b-contact connection of the sequencer, and a self-holding that represents the self-holding circuit of the sequencer. It is a sequence program creation device characterized by storing a sequence control model input using an extended Petri net including all or a part of a releasing arc.

[0007] Further, the second condition storage unit, configure a dialog box to be opened in accordance with the place to be selected on the screen, the condition and place entered in the form of a logical expression in the dialog box This is a sequence program creating device characterized by storing necessary setting information for each. Furthermore, a sequence program is created in which the necessary setting information for each place includes all or part of the label, comment, device number, operation command, input / output list to the place, timer setting value and counter setting value. It is a device.

Further, the second sequence program display means sequentially extracts the places to which the device numbers of the sequencer are to be assigned from the sequence control model, and the device number allocation place extraction means, and the sequencer model to the extracted places. Device number automatic assigning means for automatically assigning device numbers according to a predetermined rule, and a place for converting the sequence control model into the sequence program is sequentially detected according to the automatically assigned device number or a separately designated device number. And the extended condition generating means for automatically generating the extended condition by extending the applicable range of the condition corresponding to the detected place to the upstream place connected by an arc through a transition. A program conversion means for converting the generated extended condition into a list format program, and a list format sequence by adding an output command to the converted list format program according to the detected place type A list format sequence program creating means for creating a program, a ladder format sequence program creating means for creating a ladder format sequence program by converting the created list format sequence program into a ladder format program, and the above created And a display means for displaying a sequence program in a list format and / or a ladder format. A second invention is a dummy place the upper Symbol Petri nets, represents a dummy function that is not converted into only interposed E with the sequence program between the upstream places and downstream place in the sequence control model Is configured as a sequence program creating device.

[0009]

According to the first aspect of the present invention, upon converting and displaying the sequence control model that is input with Petri nets on screen in a predetermined format of a sequence program, first need to sequence control the Petri net A second model storage unit stores a sequence control model input using an extended Petri net extended to include a plurality of types of places and a plurality of types of arcs for realizing various functions. Next, the conditions input in the form of a logical expression for each place so that the state of each place included in the extended Petri net is established, and the setting information necessary for each place are stored by the second condition storage means. Then, the extended condition automatically generated based on the stored sequence control model and the condition and setting information is converted into a sequence program in a predetermined format by the second sequence program display means and displayed.

Therefore, the specification description ability by the Petri net is improved, the relation between conditions is visually expressed on the Petri net, and the creation of the sequence program is further facilitated. According to the second invention, when converting the sequence control model input using the Petri net on the screen into the sequence program of a predetermined format and displaying the sequence program, the upstream place and the downstream place in the sequence control model are displayed. A Petri net including a dummy place that represents a dummy function that is not converted is used in the sequence program by interposing only between and. Therefore, the specification description ability by the Petri net is further improved, the relation between conditions is easily expressed on the Petri net, and the sequence program is further easily created. Also, the number of auxiliary relays and the number of steps can be greatly reduced when converting from Petri nets to ladder diagrams and list programs.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the background of the present invention will be described with reference to the accompanying drawings.
The sequence program creation device will be explained.
Next, examples for embodying the present invention by improving the background art will be described to provide an understanding of the present invention. It should be noted that the following embodiments are examples of embodying the present invention, and are not intended to limit the technical scope of the present invention. Here, Figure 1 is above
2 is a block diagram showing a schematic configuration of a sequence program creating device 1 as background art, FIG. 2 is a diagram showing an example of a screen of the sequence program creating device 1, FIG. 3 is a conceptual diagram of a condition description dialog box of the device 1, and FIG. FIG. 5 is a flow chart showing a sequence program creation procedure by the device 1, FIG. 5 is an explanatory diagram showing how extended conditions are generated by the device 1, FIG. 6 is an example diagram of a sequence control mechanism, and FIG. 7 is an extended petri net by the device 1 and conditions. Example diagram, FIG. 8 is an example diagram of a list format sequence program, FIG. 9 is an example diagram of a ladder format sequence program, and FIG. 10 is a sequence program creating device according to one embodiment ( first embodiment) of the first invention of the present application . 51 is a block diagram showing a schematic configuration of 51, FIG. 11 is a diagram showing an example of a screen of the sequence program creating device 51, FIG. 12 is a functional explanatory diagram of a reference place, FIG. 3 is a functional explanatory diagram of a hierarchical place, FIG. 14 is a functional explanatory diagram of various arcs, FIG. 15 is a conceptual diagram of a condition description dialog box of the device 51, and FIG.
Flowchart showing the sequence program creation procedure by
Figure 17 is an example view of an expandable Petri net and conditions of device 51, FIG. 18 is an explanatory diagram showing the basic principle of the sequence program creating device 71 according to an embodiment of the second invention (second embodiment), FIG. 19 21 is an explanatory diagram showing an example of creating a sequence program by the device 71, FIG. 20 is an explanatory diagram showing another example of creating a sequence program by the device 51, and FIG. 21 is an explanatory diagram showing another example of creating a sequence program by the device 71.

As shown in FIG. 1, the sequence program creating apparatus 1 which is the background of the present invention converts a sequence control model input using a Petri net on the screen into a sequence program of a predetermined format. The display is similar to the conventional example. However, in this apparatus , the first Petri net that stores the sequence control input using an extended Petri net that is expanded to include a plurality of types of places for expressing the functions required for sequence control is stored.
Model storage means 2, first condition storage means 3 for storing the conditions input in the form of a logical expression for each place so that the state of each place included in the extended Petri net is established, and each of the above storages. those comprising a first sequence program display unit 4 for converting and displaying the expanded condition that is automatically generated predetermined format sequence program on the basis of the sequence control models and conditions set.

Further, the first model storage means 2 is
A state place showing the control state of the target device of the sequence control, a time place showing the timer function of the sequencer performing the sequence control, a counter place showing the counter function of the sequencer performing the sequence control, an output showing the output from the sequencer. It is also possible to store a sequence control model input using an extended Petri net formed of all or some of the places and the arithmetic places representing various arithmetic functions of the sequencer. further,
The first condition storage means 3 may constitute a dialog box opened according to the place selected on the screen, and the condition input in the form of a logical expression may be stored in this dialog box. Further, the first sequence program display means 4 combines a place detection means 5 for sequentially detecting places to be converted from the sequence control model into the sequence program, and a condition corresponding to the detected place via a transition. An extended condition generating means 6 for automatically generating the extended condition by expanding the applicable range to the created place on the upstream side, and a program converting means 7 for converting the generated extended condition into a list format program, A list format sequence program creating means 8 for creating a list format sequence program by adding an output command to the converted list format program according to the type of the detected place, and a list format sequence program creating means 8 Ladder format program for sequence programs Ladder type sequence program creating means 9 for creating a ladder format sequence program by converting the
And a display means 10 for displaying the created list format and / or ladder format sequence program .

The device 1 will be described in more detail below. FIG. 2 shows an example of a screen of input data stored in the first model storage means 2 and the first condition storage means 3, respectively. The system of the apparatus 1 is constructed on a personal computer Windows, and in the figure, 11 indicates a Petri net input editor and 12 indicates a condition description dialog box for describing conditions. still,
In this system, by double-clicking on each place, the condition description dialog box corresponding to that place is opened, and the Petri net diagram description and condition description can be performed in parallel. In the Petri net input editor 11, a necessary place type is selected from the menu 13 and can be input by dragging it with a mouse (not shown). From the left, the menu 13 represents a status place, a time place, a counter place, a calculation place, an output place, and a transition. A number called a device number (M0000, T0000, etc.) is assigned to each place, which corresponds to the input / output contact number in the sequencer and the number assigned to the internal relay. In this way, by describing a Petri net diagram by associating one line of the ladder with one place on the Petri net, even those who are familiar with the development of ladder diagrams can feel the same feeling and procedure as ladder diagrams. Therefore, a program can be created by using this device 1 without any discomfort. Further, by using the extended Petri net model in this background art , not only the flow of machine operation but also the state of each device, the state of timers and outputs, etc. can be expressed on the Petri net. However, the types of places are not limited to the types displayed in this example, and it is possible to add, for example, hierarchical places, places representing parts, and places corresponding to various other operation instructions. .

It is also conceivable to prepare a plurality of types of transitions and arcs as needed to perform a further extension function of the Petri net model. As shown in the schematic diagram of FIG. 3, the condition description dialog box 12 has a different shape depending on the type of place, and a condition required for each place can be input. All of the conditions are entered in the form of logical expressions, which is to improve the consistency with the ladder. This allows you to write a program in the same way as you used to write a ladder, and later When converting to a ladder program, it is possible to obtain a ladder program that has almost the same shape as a ladder program that was previously written directly by humans. Here,
Although the conditional expression is directly input from the keyboard (not shown), it is necessary to enable automatic input by clicking a place or operation symbol with the mouse, or to store a typical pattern in advance. You may call it at any time. Further, the contents of the condition description dialog box are not limited to the example of FIG. 3, and may be improved so that various information can be input as necessary.

Next, regarding the automatic generation of the sequence program in the first sequence program display means 4,
The process flow will be described with reference to FIG.
2, ... will be described in order. First, the order of places to be converted is determined based on the net structure of the Petri net diagram (S
1). This order is determined by searching the place along the arc by the place detecting means 5,
The output places are finally converted together according to the ladder convention. Then, regarding the first place, the condition described in the condition description dialog box 12 of the place is acquired (S2). As shown in FIG. 3, the content of the conditional description dialog box 12 differs depending on the type of place, and the conditional expression (extended condition) which is the basis of conversion by the extended condition generating means 6 is as follows. Is automatically created (S3 to S)
6).

(Rule 1) In the case of status place and output place: <With self-holding> Conditional expression = (conditional expression in condition column + device number of place)
* OFF Condition column conditional expression <without self-holding> Conditional expression = Conditional column conditional expression For time place, counter place, operation place: Conditional expression = Conditional column conditional expression Next, the input transition of this place is Check if there is one. If there is not, the conditional expression obtained by the above Rule 1 becomes the conversion target as it is. However, if it exists, all the input places to the transition are checked for all the input transitions, and the device numbers of the obtained places are acquired. Then, it is combined with the conditional expression obtained in the above rule 1 according to the following rule.

(Rule 2) When there is only one input transition to the conversion target place as shown in FIG. 5A: Conditional expression = device number of b1 * device number of b2 *.
.. Conditional expression of device number * a of * bn When there are multiple input transitions to the conversion target place as shown in FIG. 5B: Conditional expression = (device number of b1 + device number of b2 +
(+ Bn device number) * a conditional expression The conditional expression obtained in this way is the object of conversion, and the list format program is automatically converted by using the program conversion means 7 for decoding and converting this conditional expression. Generate (S7).

Next, the list format sequence program creating means 8 adds an output command to the list program thus generated (S8). Output commands are added according to the following rules. (Rule 3) The following output command is added to the list program obtained above. For status place and output place: OUT device number For time place: OUT Device number For time value counter place: OUT device number For count value operation place: Add the condition in the operation column as it is The conversion process of the place into the sequence program ends. After that, a list-format sequence program can be obtained by repeating similar conversion for all places (S
9). If the generated sequence program is to be viewed in the ladder format instead of the list format, the obtained list format program can be easily converted by using the ladder format sequence program creating means 9 for converting the program in the ladder format. It can be done (S10, S11). The list format and / or ladder format sequence program thus obtained is displayed by the display means 10 (S12).

The background art using the device 1 will be briefly described below. In this specific example, a piston in one jig and one cylinder as shown in FIG. 6 is moved. First, when the push-out button X1 is pressed, an output signal is output to the solenoid Y1 on the output side and the piston is output. The piston stops when the limit switch X3 on the exit side turns on. that time,
The timer monitors the time-out, and if the limit switch X3 does not turn on after 5 seconds, the time-out occurs, and the red lamp Y3 that indicates the time-out lights up, and the count value is updated and the data set process is performed at the same time. Shall be performed. If the limit switch X3 is turned on within the specified time and the process ends normally, the green lamp Y
4 shall be illuminated. Similarly, when the return push button X2 is pressed, an output signal is output to the return side solenoid Y2 to move the piston in the return side direction, and when the return side limit switch X4 is turned on, the piston stops. Also at this time, the timer is monitoring the time-out, and if the limit switch X4 does not turn on after 5 seconds, the time-out occurs and the red lamp Y3 that indicates the time-out lights up, and the count value is updated at the same time. Data set processing shall be performed. Further, when the limit switch X4 is turned on within the time and the processing is normally completed, the green lamp Y5 is turned on. FIG. 7 shows an example in which the above operation is represented by the extended Petri net of the present apparatus 1 and the conditional expression. Originally, the conditional expressions are individually described in the conditional description dialog box 12, but in this example, only the necessary ones are collectively described. FIG. 8 shows a case where these outputs are converted into a list format program, and FIG. 9 shows a case where they are converted into a ladder format program.

As described above, when the sequence program creating apparatus 1 according to the background art is used, the extended Petri net is used by expanding the Petri net by preparing a plurality of types of places for realizing the necessary functions in sequence control. Based on the sequence control model that is input in the form and the conditions such as operation and processing that are input in the form of a logical expression for each place, while visually expressing the control flow and the state of each device by Petri net, Programs can be created and displayed by methods that take advantage of each other's strengths, such as programs can be created in which the features of conventional ladder programming are fully incorporated. Moreover, if the equipment 1, because the correspondence between the Petri net and ladder can be taken well, the sequence program that has been generated has been resolved very problem that the reading has been difficult, the sequence program to be generated is human-created It is possible to obtain the same quality as that obtained. In addition, since the method of opening a dialog box for each place and inputting conditions is adopted, it is possible to efficiently create a program on the screen. By the way, in the background art described above, a Petri net diagram is described by associating one line of a ladder with one place on the Petri net, and a condition for establishing the state of the place (contact of the ladder) Information) is described using a logical formula. Since the conditions normally required is relatively simple, the back
Scenic technology can handle it sufficiently. However, with this background technology ,
Since the conditions described by the logical expressions are not visible on the Petri net and the relationships between the conditions are difficult to understand, it is difficult to express them in logical expressions if the conditions become more complicated, and the relationship of the conditions can be understood by looking at the logical expressions. it is expected the case to Dzu leprosy.

Therefore, in order to deal with such a case, the inventors further expand the expanded Petri net by adding a so-called input place or the like ( first invention),
It was decided to further expand ( second invention) by introducing a so-called dummy place. First of all ,
Described for the first invention that. As shown in FIG.
A sequence program creating device 51 according to an embodiment ( first embodiment) of the first invention converts a sequence control model input using a Petri net on a screen into a sequence program of a predetermined format and displays the sequence program. The point is similar to the conventional example. However, in the first embodiment, a sequence input using an extended Petri net that expands the Petri net to include multiple types of places and multiple types of arcs for expressing the functions required for sequence control. Second model storage means 52 for storing a control model, conditions input in the form of a logical expression for each place so that the state of each place included in the extended Petri net is established, and setting information necessary for each place A second condition storing means 53 for storing the second condition, and a second condition for converting and displaying the extended condition automatically generated on the basis of the sequence control model and the condition and the setting information, which are respectively stored, into a sequence program of a predetermined format. Sequence program display means 54
It is different from the conventional example in that

Further, the second model storage means 52
, A status place showing the control state of the target device of the sequence control, a time place showing the timer function of the sequencer performing the sequence control, a counter place showing the counter function of the sequencer performing the sequence control, and an output from the sequencer. All or part of the output place that represents, the operation place that represents the various calculation functions of the sequencer, the input place that represents the input to the sequencer, the reference place that refers to the on / off information of other places, or the Petri net hierarchically The hierarchical place described in 1), or the a contact connection arc that represents the a contact connection of the above sequencer, and the b that represents the b contact connection of the above sequencer.
It is also possible to store the sequence control model input using an extended Petri net that includes all or part of the contact connection arc and the self-hold release arc that represents the self-hold circuit of the sequencer. Furthermore, the second condition storage means 53 constitutes a dialog box opened according to the place selected on the screen, and the condition and place that are input in the form of a logical expression in this dialog box are necessary for each place. The setting information may be stored. Further, the setting information required for each place may include a label, a comment, a device number, a calculation instruction, an input / output list for the place, a timer setting value, and a counter setting value, in whole or in part. .

Further, the second sequence program display means 54 includes a device number allocation place extraction means 55 for sequentially extracting the places to which the device numbers of the sequencer are to be allocated from the sequence control model,
A device number automatic assigning means 56 for automatically assigning the device number of the sequencer to the extracted place according to a predetermined rule, and a device number for automatically assigning a place for converting the sequence control model to the sequence program. Alternatively, the above-mentioned expansion is performed by expanding the applicable range to the place detection means 57 that sequentially detects according to the separately designated device number and the condition corresponding to the detected place to the upstream place connected through the transition. Depending on the type of the detected place in the converted list format program, the extended condition generating means 58 for automatically generating the condition, the program converting means 59 for converting the generated extended condition into a list format program. By adding an output command List to create a list format of the sequence program format sequence program creating means 60
And a ladder format sequence program creating means 61 for creating a ladder format sequence program by converting the created list format sequence program into a ladder format program, and the created list format and / or ladder format Display means 62 for displaying the sequence program may be provided. These points are also different from the conventional example.

The device 51 will be described in more detail below. FIG. 11 shows a screen example of input data stored in the second model storage means 52 and the second condition storage means 53, respectively. The system of this device 51 is constructed on a personal computer Windows, 63 indicates a Petri net input editor, and 64 indicates a condition description dialog box for describing conditions.
In this system, by double-clicking on each place, the condition description dialog box corresponding to that place is opened, and the Petri net diagram description and the condition description can be performed in parallel. In the Petri net input editor 63, a necessary place type is selected from the icon 65 and can be input by dragging it with a mouse (not shown). The icon 65 represents an input place, an output place, a status place, a time place, a counter place, a calculation place, a reference place, a hierarchical place, and a transition from the left in FIG. Among these, the input place represents an input signal of the sequencer, and an example thereof is an output side button indicated by a triangle in the screen of FIG. The output place, the status place, the time place, the counter place, and the operation place are the same as those in the background art .
The explanation is omitted here. The reference place refers to on / off information of a place that is an arbitrary entity, and is shown in FIG.
An example thereof is the jig 1 protrusion limit, which is indicated by a wedge in the screen. That is, there is only one place that is the substance of a certain label on the screen, and when it is desired to use the information of that place for another place, etc., that place is usually connected to another place by an arc. However, if the number of arcs increases, the arcs will intersect and the screen will be difficult to see. Therefore, it is possible to make the screen easier to see by substituting the place in the reference place and omitting the arc from the screen (see FIG. 12).

The hierarchical place describes the Petri net hierarchically. That is, when there are many places on the screen and the entire structure is difficult to see, or when a certain partial structure is repeated, the partial structure is collectively expressed as, for example, “tier 1” to make the entire structure easy to see. ， Also, the trouble of inputting can be omitted. The contents of "Level 1" can be displayed in the sub-window by clicking the place in the main window (see FIG. 13). In addition, the arc is from the menu (not shown)
The user can select and use the b-contact connecting arc and the self-holding releasing arc.
It has a function as shown in FIG. That is, FIG. 14 (1)
In the arc for connecting a contact shown in (1), the place b is turned on when the place a is turned on. In the b-contact connecting arc shown in FIG. 14 (2), when the place a is turned off, the place b is turned on. In the self-holding release arc shown in FIG. 14C, when the place a is in the on state (places b and c are in the off state), the place d is in the on state and the self-holding state is set. Then place b
Alternatively, when c is turned on, the self-holding state is released.

A label representing comment information can be set in each place, and the meaning of the place is expressed. Also, when converting to a sequence program,
Device numbers (M0, T0, etc.) are automatically assigned to each place. This corresponds to the input / output contact number in the programmable controller and the number assigned to the internal relay. Note that this device number can be specified by the user as needed instead of being assigned automatically. In the first embodiment, the extended Petri net in the background art is further extended in this way, and all the conditions including the condition for establishing a place (contact information of the ladder) are achieved. It became possible to describe by Petri net. Therefore, the relationship between conditions can be visually expressed on the Petri net, and the program can be created more easily. Also, as with the background art described above, even a person who has become familiar with development using ladder diagrams can create programs using this system with the same feeling and procedure as ladder diagrams. Further, by using the extended Petri net of the second embodiment, not only the flow of machine operation but also the state of each device and the state of timers and outputs can be expressed on the Petri net. The types of places and arcs are not limited to the types displayed in the first embodiment, and new types can be added.

Next, FIG. 15 shows a schematic diagram of the condition description dialog box in the first embodiment. This dialog box has different shapes depending on the type of place, and you can enter the necessary information for each place. Here, basically all conditions are described by Petri nets, so it is not necessary to describe the conditions using logical expressions,
If the conditions are simple or if you want to reduce the number of places, it is possible to describe in the form of a logical expression as in the background art above. The content of the condition description dialog box is not limited to the example of FIG. 15, and may be improved so that various information can be input as necessary. Next, the automatic generation of the sequence program in the second sequence program display means 54 will be described in the order of steps S51, S52, ... With reference to FIG.

First, the device number allocation place extraction means 55 automatically selects the place to which the device number is allocated based on the net structure of the Petri net diagram (S51). In this case, the input and output places are omitted because the user basically needs to specify the number.
Due to the nature of operations, references, and hierarchical places, it is not necessary to assign device numbers. The device numbers are automatically allocated to the selected places by the device number automatic allocation means 56 according to a predetermined rule (for example, in the selected order) (S52, S53).
In the background art described above, it was necessary for the user to manually assign all device numbers, but by using this method, the labor can be reduced. The predetermined rule can be arbitrarily set by the user. Next, the order of places to be converted is determined based on the net structure of the Petri net diagram (S54). This order is determined by searching the places along the arc by the place detecting means 57, but the output places are collectively converted at the end according to the convention of the ladder. Then, for the first place, the condition described in the condition description dialog box of the place is acquired (S55). As shown in FIG. 15, the contents of this conditional description dialog box differ depending on the type of place, and the extended conditional generation means 58 automatically creates the conditional expression which is the basis of conversion by the following rules (S56). ~ S59).

(Rule 2-1) State, output, time, counter, operation place: Conditional expression = conditional expression in condition column (other places have no condition.) Next, input transition to this place Check if there is. When there is no input transition, the conditional expression obtained in the above Rule 2-1 is directly subjected to conversion. However, when there is an input transition, all the input places to the transition are checked for all the transitions, and the device number of the obtained place is acquired. And the above background techniques as follows
It is combined with the conditional expression obtained in the above Rule 2-1 by the same rule as the above. (Rule 2-2) When there is only one input transition to the conversion target place as shown in FIG. 5A: Conditional expression = device number of b1 * device number of b2 *.
.. Conditional expression of device number * a of * bn When there are multiple input transitions to the conversion target place as shown in FIG. 5B: Conditional expression = (device number of b1 + device number of b2 +
... + bn device number) * a conditional expression

Here, it is possible to set the self-holding state in the status place and the output place. The self-holding is expressed by using the self-holding release arc as shown in FIG. 14 (3), and converted by the following rules. (Rule 2-3) In the case of self-holding: Conditional expression = (condition of d + device number of d) * self-holding release condition of d The conditional expression thus obtained becomes the target of conversion, and this conditional expression is decoded. Then, the program in the list format is automatically generated using the program converting means 59 for converting (S6).
0).

Next, the list format sequence program creating means 60 is added to the list program thus created.
A process for adding an output command is performed by (S61). The output command is added according to the same rule as the above background art . (Rule 3) The following output command is added to the list program obtained above. For status place and output place: OUT device number For time place: OUT Device number For time value counter place: OUT device number For count value operation place: Add the condition in the operation column as it is The conversion process of the place into the sequence program ends. After that, by repeating the same conversion for all the places, a list format sequence program can be obtained (S6).
2). If the generated sequence program is to be viewed in the ladder format instead of the list format, the obtained list format program is easily converted by using the ladder format sequence program creating means 61 for converting the program in the ladder format. Can be performed (S63, S64).

The list format thus obtained and /
Alternatively, the ladder-type sequence program is displayed on the display unit 62.
Is displayed by (S65). FIG. 17 shows the result of applying the above-described first embodiment to the example of FIG. 6 as in the background art . Moreover, as a result of converting these into a list format program by the second embodiment,
The result of conversion into the program of the ladder format is the same as that of FIG. 8 and FIG. 9, respectively. As described above, according to the first embodiment, the specification description ability by the Petri net is improved, so that the specification can be described only by the Petri net without using the conditional description by the logical expression. As a result, the relationship between conditions can be visually expressed on the Petri net and the program can be created easily. Furthermore, the addition of a function that automatically assigns device numbers to places has reduced the time and effort for assigning device numbers by the user.

Next, the second invention will be described.
The second invention is applicable to both the background art and the devices 1 and 51 according to the first embodiment, but in the following, when applied to the device 51 (for convenience of explanation, it will be referred to as device 71). ) Is illustrated. For example as shown in FIG. 10, one embodiment of the second invention (second embodiment) in the sequence program creating device 71 according the sequence control model that is input with Petri nets on the screen a predetermined format This is the same as the conventional example in that it is converted into a sequence program and displayed. However, in the second embodiment, the Petri net represents a dummy function that is interposed only between the upstream side and the downstream side in the sequence control model and is not converted into the sequence program. It differs from the conventional example in that it includes a dummy place.

[0035] Hereinafter, will be explained by comparing the basic principle of the second embodiment and that of the second embodiment. For example, in FIG. 18, if X1, X2, and X3 are all places, the Petri net of the second embodiment expresses the overall relation (X1 or X2) between the conditions of each place and X3; Figure 1 when converted to a list program
This is as shown in 8 (1). That is, it is expressed by two partial relationships (a) and (b). In this case, (a),
The number of auxiliary relays, which is the sum of (b), is two (M1, M
2) The number of steps in the list program is 6. Next, the above (X1 or X2) and X3;
18 (2) when Petri net representation is performed by using the apparatus 71 of FIG. That is, it is expressed by one whole relation. in this case,
There is one auxiliary relay (M1) and the number of steps of the list program is four steps, which is one auxiliary relay and the number of steps is reduced by two steps as compared with the case of using only the Petri net of the second embodiment. .

This is because the dummy place is interposed in the sequence control model on the screen. Although this dummy place is completely useless in the list program, it is a so-called insubstantial place that makes it easy to visually understand the relationship between conditions only on the screen. Next, the conversion process of the sequence control model expressed by a Petri net including a dummy place as shown in FIG. 19 will be described in detail. In this case, step 6 in the second embodiment described above.
The following rules are added to (Rule 2-3) in 0. Other processes are the same as the steps in the second embodiment, and therefore their explanations are omitted here. (Rule 2-4) In the case of dummy place: Does not have a conditional expression. That is, no conversion operation is performed. (Rule 2-5) When there is a dummy place (D) in the input places of the input transition to a certain place (conversion target a): For all the input transitions to the dummy place (D), Examine all the input places, and all the input places are the places a to be converted.
It is directly connected to the input transition to (1) to (2), (2) and (3), and a conversion is performed by creating a conditional expression.

In the following, more complicated condition settings were made in order to confirm the effect of the second embodiment. That is, the whole relation between the place conditions [{(X1 or X2) and (X3 or X4)} or X5] and X6 is expressed by the trinet of the first embodiment and converted into a list program. Twenty. On the other hand, when it is expressed by the extended Petri net of the second embodiment and converted into a list program, the result is as shown in FIG. 21, and it was confirmed that the effect of the third embodiment becomes remarkable. As described above, according to the second embodiment, the specification description ability by the Petri net is further improved, the relation between the conditions is easily expressed on the Petri net, and the sequence program is further easily created. . Also, when converting from Petri nets to ladder diagrams and list programs, the number of auxiliary relays,
The number of steps can be significantly reduced.

[0038]

The sequence program creating device according to the present invention (first and second inventions) has the following effects because it is configured as described above . (1 ) Further, by further expanding the expanded Petri net by adding plural kinds of places and plural kinds of arcs, the specification description ability by the Petri net is improved, and the relation between conditions can be easily made on the Petri net. This makes it easier to create a sequence program. Further, the addition of the function of automatically allocating the device number to the place saves the user the trouble of allocating the device number ( first invention). ( 2 ) Furthermore, by extending the Petri net by adding dummy places, the specification description ability by the Petri net is further improved, the relation between conditions is easily expressed on the Petri net, and the creation of the sequence program is further enhanced. It will be easy. Also, when converting from Petri nets to ladder diagrams and list programs, the number of auxiliary relays and the number of steps can be significantly reduced ( second invention).

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a sequence program creation device 1 according to a background art .

FIG. 2 is a diagram showing an example of a screen of the sequence program creating device 1.

FIG. 3 is a conceptual diagram of a condition description dialog box by the device 1.

FIG. 4 is a flowchart showing a sequence program creation procedure by the device 1.

FIG. 5 is an explanatory diagram showing how extended conditions are generated by the device 1.

FIG. 6 is an example diagram of a sequence control mechanism.

FIG. 7 is an example diagram of an extended Petri net and conditions by the device 1.

FIG. 8 is an example diagram of a list format sequence program.

FIG. 9 is an example diagram of a ladder format sequence program.

Figure 10 is a block diagram showing a schematic configuration of a sequence program creating apparatus 51 according to an embodiment (first embodiment) of the first invention.

FIG. 11 is a diagram showing an example of a screen of the sequence program creating device 51.

FIG. 12 is a functional explanatory diagram of a reference place.

FIG. 13 is a functional explanatory diagram of a hierarchical place.

FIG. 14 is a functional explanatory diagram of various arcs.

FIG. 15 is a conceptual diagram of a condition description dialog box of the device 51.

FIG. 16 is a flowchart showing a sequence program creation procedure by the device 51.

FIG. 17 is an example diagram of an extended Petri net and conditions by the device 51.

FIG. 18 is an explanatory diagram showing the basic configuration of a sequence program creation device 71 according to an embodiment (second embodiment) of the second invention.

FIG. 19 is an explanatory diagram showing an example of creating a sequence program by the device 71.

20 is an explanatory diagram showing another example of creating a sequence program by the device 51. FIG.

FIG. 21 is an explanatory diagram showing another example of creating a sequence program by the device 71.

[Explanation of symbols]

1. Sequence program creation device 2 ... First model storage means 3 ... First condition storage means 4 ... First sequence program display means 5: Place detection means 6 ... Extended condition generating means 7 ... Program conversion means 8 ... List format sequence program creating means 9 ... Ladder format sequence program creation means 10 ... Display means 51, 71 ... Sequence program creation device 52 ... Second model storage means 53 ... Second condition storage means 54 ... Second sequence program display means 55 ... Device number allocation place extraction means 56 ... Device number automatic allocation means 57 ... Place detection means 58 ... Extended condition generating means 59 ... Program conversion means 60 ... List format sequence program creating means 61 ... Ladder format sequence program creating means 62 ... Display means

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoki Tamura 1-5-5 Takatsukadai, Nishi-ku, Kobe City, Hyogo Prefecture Kobe Steel Works, Ltd. Kobe Research Institute (72) Inventor Tetsuya Takahashi Nishi-ku, Kobe City, Hyogo Prefecture 1-5-5 Takatsukadai Kobe Steel Co., Ltd., Kobe Research Laboratory (72) Inventor, Takashi Morita 1-5-5 Takatsukadai, Nishi-ku, Kobe, Hyogo Kobe Steel Works, Kobe Research Laboratory (72) Inventor Masayuki Hisho 15-1 Nakahara, Miyaya-cho, Toyohashi-shi, Aichi Co., Ltd.Kobe Steel Works, Toyohashi factory (72) Inventor Haruo Okumura 15-1 Nakahara, Miya-cho, Toyohashi-shi, Aichi Co., Ltd. Kobe Steel, Toyohashi Plant (56) Reference JP 4-18605 (JP, A) JP 64-38804 (JP, A) JP 61-233803 (JP, A) JP JP -72920 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB name) G05B 19/05 G05B 23/02

Claims (8)

(57) [Claims] 1. A sequence program creating apparatus for converting a sequence control model input using a Petri net on a screen into a sequence program of a predetermined format and displaying the sequence program, wherein the Petri net realizes a function necessary for sequence control. A second model storage means for storing a sequence control model input using an extended Petri net extended to include a plurality of types of places and a plurality of types of arcs, and included in the extended Petri net. Second condition storage means for storing conditions input in the form of a logical expression for each place so that the condition of each place is established, and setting information necessary for each place, and the sequence control model and conditions stored respectively above And a sequence program of a predetermined format with extended conditions automatically generated based on the setting information Second to convert and display
And a sequence program display means for storing the sequence program. 2. The second model storage means is a status place indicating a control status of a device subject to the sequence control,
A time place that represents the timer function of the sequencer that performs the sequence control, a counter place that represents the counter function of the sequencer that performs the sequence control, an output place that represents the output from the sequencer, an operation place that represents the various operation functions of the sequencer, and the above A sequence control model stored by using an extended Petri net including all or part of an input place representing input to a sequencer and a reference place referencing on / off information of another place is stored. Item 1. A sequence program creation device according to item 1 . Wherein said second model storage means according to claim 1, wherein the storing sequence control model that is input using an extended Petri nets including hierarchically describes hierarchical place Petri nets Sequence program generator. 4. The second model storage means represents an a-contact connecting arc that represents an a-contact connection of the sequencer, a b-contact connecting arc that represents a b-contact connection of the sequencer, and a self-holding circuit of the sequencer. sequence program creating device according to claim 1, wherein the storing sequence control model that is input using an extended Petri nets comprising all or part of the self-holding release for arc. 5. The second condition storage means constitutes a dialog box opened according to a place selected on the screen, and each condition and place inputted in the form of a logical expression in the dialog box sequence program generating apparatus according to any of claims 1 to 4, characterized in that stores setting information necessary. 6. The setting information required for each place is
6. The sequence program creating device according to claim 5, which includes a label, a comment, a device number, an operation command, an input / output list for the place, a timer setting value, and a counter setting value, in whole or in part. 7. A device number allocation place extracting means for sequentially extracting a place to which a device number of the sequencer is to be allocated from the sequence control model by the second sequence program display means, and a device of the sequencer for the extracted place. A device number automatic assigning means for automatically assigning numbers according to a predetermined rule, and a place for converting the sequence control model into the sequence program is sequentially detected according to the automatically assigned device number or a device number designated separately. A place detecting means, and an extended condition generating means for automatically generating the extended condition by expanding the applicable range of the condition corresponding to the detected place to an upstream place connected by an arc through a transition, Above raw A program conversion means for converting the generated extended condition into a list format program, and a list format sequence program by adding an output command to the converted list format program according to the type of the detected place. A list format sequence program creating means for creating, and a ladder format sequence program creating means for creating a ladder format sequence program by converting the created list format sequence program into a ladder format program,
Sequence program generating apparatus according to any of claims 1 to 6, characterized in that comprises a display means for displaying the of the list created form and / or a ladder format sequence program. 8. The Petri net includes a dummy place representing a dummy function which is interposed only between an upstream place and a downstream place in the sequence control model and is not converted into the sequence program. Contract
The sequence program creating device according to any one of claims 1 to 7 .