JPS5999504A - Sequence control system - Google Patents

Abstract

PURPOSE:To change sequences easily by using a microcomputer for control operation based upon information in tables. CONSTITUTION:Sequence control is carried out while the tables are referred to. Those tables includes a table stored with the start condition of transition from some state (stage) to another stage and a table stored with the destination stage at the time of transition from some stage. Pieces of table information are stored in an ROM in the relation between the numbers of stages and numbers given corresponding to the condition of the start. A microcontroller performs the sequence control operation on the basis of those pieces of table information. In this case, the table information is only generated and another troublesome procedure is unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sequence control method using a microprocessor.

Sequence control is usually defined as "control in which each stage of control is sequentially advanced in accordance with a predetermined order or condition."

Therefore, it can be said that not only the input-output relationship of the sequence control circuit that performs the control but also the causal relationship within the circuit are clear. However, the objects of sequence control, such as valves, electric motors, or pumps, have qualitative expressions such as open, close, start, and stop, and therefore academic systemization has been delayed. The design of sequence control circuits is highly dependent on the designer's "intelligence" or "experience," and the current situation is that the control method is not standardized. On the other hand, the development of microcomputers has been remarkable recently, and sequence control devices are shifting from those based on relays and timers to microcontrollers with built-in microcomputers. One of the advantages of adopting such a microcontroller is the ease of modification, as the sequence (program) can be easily modified using a program loader (without having to change the wiring as in the past). However, it is not always easy to program this program incorrectly, and there has been a desire for a sequence control system that can easily make such changes.

This invention has been made in view of the above, and provides a sequence control method using a highly reliable microcontroller that can be designed with a short man-hour, can easily and quickly respond to any changes without error, and is highly reliable. The purpose is to

Its features include a table that stores activation conditions for transitioning from a state (hereinafter also referred to as a stage) to the next state, and a table that stores the transition destination stage when transitioning from a stage to the next stage. , a table for storing transition start conditions at the transition destination stage and a table for storing information to be output at each stage are provided, and when a predetermined start condition is given in a predetermined state, transition is performed by referring to these tables. The point is that the stage to be outputted and the information to be outputted at that point are known, and a predetermined control operation is performed based on this information.

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

FIG. 1 is an explanatory diagram for explaining the sequence operation,
Figures 2 to 6 are explanatory diagrams for explaining various lists, Figure 7
The figure is a schematic diagram showing an embodiment of the invention.

In other words, Figure 1 shows a series of control operations from the initial state through various states such as cleaning, raw material reception, stirring, temperature control, chemical addition, dispensing, cooling, and emergency stop. An example of what is done is shown. The circles in the figure represent each of these states (stages), and the arrows indicate the direction in which the states transition. Also, along with this arrow, conditions for state transition are described, and these states and conditions are numbered A1. B1 and name A2. Content B
2nd prize will be awarded. For example, the name of the 9AU stage (stage name) is "6 initial" and -8 (stage No.
) is "1" and the level is below L at the payout stage with the same number '7' (starting condition number pa 1)
This is the transition destination stage when 2”) is established.
When the command "auto", operation of the start pushbutton switch (FB), and a condition (start condition number "1") are given, the process shifts to the cleaning stage of stage No. 2. In this case, the transmitting side of the arrow in the figure is called the leading stage, and the receiving side is called the trailing stage.For example, the relationship between these and the activation condition number and the relationship between the leading stage and the trailing stage is the second stage.
It is shown as shown in Figure 6. In other words, the m2 diagram is a list of activation conditions that shows the correspondence between activation conditions and activation condition numbers (activation NOs) (in the diagram, the "△" mark means logical product).
, FIG. 3 is a preceding stage activation list that shows the relationship between preceding stages and activation numbers, and for the preceding stage, when the activation condition represented by the activation number marked with a circle is satisfied,
This indicates a transition to a predetermined stage. Also,
FIG. 4 is a stage transition list showing the relationship between the preceding stage and the succeeding stage, and FIG. 5 is a succeeding stage activation list showing the relationship between the succeeding stage and activations N and 0. FIG. 6 is an output list that defines the information to be output at each stage, and the foil stage to be output is marked with a circle. Stage No. assigned in this way
The correspondence between the start condition NO and the starting condition NO is stored in the memory of the microcontroller MCT circle in FIG.

The microcontroller MCT monitors its input IN and various activation conditions, and when a predetermined activation condition is given at a predetermined time, determines the state to which it should transition from various lists or files stored in memory, Various information OUT as shown in FIG. 7 is output.

The operation of the microcontroller will be explained in more detail with reference to FIG. Note that FIG. 8 is a detailed diagram showing the microcontroller in detail.

In FIG. 8, 11 to 14 are tables storing the lists shown in FIGS. 3 to 6, respectively, 2 is a stage monitoring unit, and 3iI
4 is a stage updating section; and 5 is an output section.

Now, assuming that the stage number is 2" and the starting condition number is '3', the stage counter 2 of the stage monitoring section 2
The content of 1 is '2'', and the content of the activation counter 31 for activation condition determination \I!>3 is t(3II).Therefore, the contents of stage No. ``2'' of the table 11 are read to the register 22. However, for example, °゛1'' is stored in the position indicating the activation number of that stage, so this is compared with the contents of the activation counter of the activation condition determination unit 3 to determine whether a transition is necessary.Here, ,.Stage 2 starts wJN
Assuming that the transition occurs at O3, the stage update unit 4 sequentially reads the contents of the preceding stage NO2 in the table 12 into the register 23, and searches for the transition destination (following) stage. That is, the stage to which the transition is to be made is identified by checking the contents of the register 23 in order from the left and counting, for example, the pit position where '1' is set in the trailing stage counter 24.

Nao, in this case, trailing stage No. and register 23゜2
It is assumed that the pit positions of 6 correspond to each other.

Also, the output of the counter 24 (here jl 31j)
reads the contents of the trailing stage No. 3 of the table 13 to the register 26, checks whether or not the trailing stage is activated based on the activation condition No. given from the activation counter 31, and after confirming activation, the counter If the contents of 24 are correct, stage counter 2
Give to 5. Since the following stage number is determined by this, the contents of the table 14 corresponding to the count value of the stage counter 250 are read out, and predetermined commands are given to various devices or devices via the output section 5.

As described above, according to the present invention, predetermined sequence operations are defined using various tables, so there is no need to consider what is generally called a program, and the number of man-hours required when changing sequence operations is reduced. This has the advantage that the design can be easily changed. In addition, there are no special restrictions on the allocation of stage numbers, startup numbers, etc., and the stage number and the causal relationship between the stage number and startup number can be arbitrarily defined using a table, so when adding a stage, the current stage This method has the advantage that it is not necessary to change the NO or activation NO, that is, to change the current sequence operation.

Since this invention has no particularity for each brand, it can be applied to any field that requires sequence control, and the larger the scale, the more pronounced its effects will be.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram for explaining the sequence control operation, FIGS. 2 to 6 are explanatory diagrams for explaining various lists, FIG. 7 is a schematic diagram showing another embodiment of this invention, and FIG. 1 is a detailed diagram showing a sequence control circuit according to the invention in detail; FIG. Code explanation 11... Preceding stage activation table, 12...
...Stage transition table, 13...Successful stage activation table, 14...Output table, 2...Stage monitoring section, 3...Startup Condition determination unit, 4...- Stage update unit, 5...
... Output section, 21, 24, 25, 31 ... Counter, 22, 23, 26 ... Register agent Patent attorney Akio Namiki Patent attorney Kiyoshi Matsuzaki 4th Figure Chopsticks 5 Figure 6

Claims (1)

[Claims] A sequence control method that sequentially performs a series of control operations while repeating an operation of transitioning to a predetermined next step when a predetermined condition is satisfied in a step,
A first table that stores activation conditions for transitioning from a step to the next step, a second table that stores a transition destination step when transitioning from a step to the next step, and a destination step. a third table that stores the transition activation conditions in the step; a fourth table that stores the information to be output in each step; and a fourth table that stores the information to be output at each step; A controller that determines and determines a transition destination step by referring to the first to third tables, and reads out output information defining the movement to be performed in the step from the fourth table in FiiJ and performs a predetermined control operation. A sequence control method characterized by comprising: