JPS60163104A - Programmable controller with reverse sequence operating function - Google Patents

Abstract

PURPOSE:To attain ease of reverse sequence operation of a process by storing the execution order of a forward operating instruction. CONSTITUTION:The forward operating instruction is executed at the step 1 and also ''1'' is stored in a forward operating execution sequence recording table. The forward operating instruction 2 is executed at the step 2 and ''2'' is stored in the forward operating execution sequence recording table. The operating condition is discriminated by a discrimination instruction 1 at the step 3, resulting that the step is bypassed at the step 4 and enters the next step 5, the forward operation instruction 4 is executed and ''4'' is stored in the forward operating execution sequence recording table. The similar operation is conducted till the step 8. If any error takes place in this state, since the step numbers are stored as 6, 5, 4, 2, 1 in the reverse order in the forward operating execution recording table, the corresponding instruction is selected from a reverse operating instruction table corresponding one to one to the forward operation in the sequence above and the sequence is executed in the reverse order.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a programmable controller with a reverse order operation function.

[Technical background of the invention and its problems] When controlling a process in sequence, a programmable controller (hereinafter referred to as PLO), which is flexible and easy to create and change sequences, is generally used, but when an abnormality occurs in the process. In some cases, the sequence may be reversed to return the process to the state it was in before the error occurred.

Conventionally, the operation is switched to manual and the operator reverses the process to return to the state before the abnormality occurred, but this has drawbacks such as the difficulty of accurately retracing the sequence when the sequence becomes complex.

[Object of the Invention] The present invention provides a method for implementing PI without imposing a burden on the operator.
It is an object of the present invention to provide a programmable controller with a reverse operation function that accurately follows G sequence output steps in reverse order.

[Summary of the Invention] The present invention provides a reverse direction operation instruction table that stores reverse direction operation instructions in one-to-one correspondence with forward direction operation instructions, and a forward direction operation instruction table that stores the execution order of the forward direction operation instructions that operate in the forward direction according to a program. A motion execution order recording table is provided, and in response to a reverse motion command, the reverse motion corresponding to the forward motion is executed in the reverse order of the forward motion stored in the forward motion execution order recording table. This is a programmable controller with a reverse operation function that automatically executes forward and reverse operations without placing any burden on the operator.

[Embodiments of the invention] An embodiment of the present invention is shown in FIG.

FIG. 1A is a flowchart showing the forward operation, and FIG. 1B is a flowchart showing the reverse operation.

Further, FIG. 2 is an execution order record table of forward motion commands when the sequence program of FIG. 1A is executed,
FIG. 3 shows a table that stores direction movement commands that correspond one-to-one to forward movement.

In FIG. 1A, first, in step 1a, forward direction motion command 1 is executed, and in step 1b, 1 is stored in the forward direction motion execution order record table of FIG.

Next, in steps 2a and 2b, forward direction operation command 2 is executed and 2 is stored in the forward direction operation execution order record table.

In the next step 3, the operation condition is determined by the judgment instruction 1, and as a result, steps 4a and 4b are bypassed and the next step 5a and 5b is entered, where the forward direction operation instruction 4 is executed and the forward direction operation is executed. 4 in the order record table
is memorized.

In the next step 6, the operating condition is determined by the judgment instruction 2, and as a result, steps 7a and 7b are not bypassed, and the forward direction operation instruction 5 is executed, and 5 is stored in the forward direction operation execution order record table. Ru.

Next, forward direction operation command 6 is executed by the programs of steps 8a and 8b, and 6 is stored in the forward direction operation execution order record table.

If an abnormality occurs in this state, 6 will appear in the forward motion execution record table in FIG. 2 if traced in reverse order.

5.4, 2.1, so the third
A corresponding command is selected from the reverse motion command table shown in the figure, and the sequence is executed in reverse order as shown in FIG. 1B.

In the case of Figure 2, N=5 and I=5.4.3.2.1
Forward motion corresponding to 6, 5, 4, 2.

The reverse direction operation commands corresponding to 1 are executed sequentially.

If it is necessary to execute some auxiliary instructions when executing each reverse direction operation instruction, it is also possible to execute these auxiliary instructions in combination with each reverse direction operation instruction.

[Effects of the Invention] As explained above, according to the present invention, the order of execution of forward motion commands is stored, and when a reverse motion is required, the stored contents are traced back and stored in reverse order. Since a reverse direction operation command corresponding to the content is selected and executed, even a complicated sequence does not place a burden on the operator, and the operation can be performed accurately in the reverse order.

Furthermore, since the sequence program shown in FIG. 1 and the reverse direction operation command table shown in FIG. 3 are independent from each other, there are excellent effects such as the ability to easily change the reverse direction operation.

[Brief explanation of drawings]

1A and 1B are flowcharts showing one embodiment of the present invention, and FIGS. 2 and 3 are examples of a forward direction operation execution order record table and a reverse direction operation command table, respectively, used in the present invention. Agent bu [Science rules near: bu i/i (+x or 1 person) Fig. 1 (f3) (β) Fig. 2 Fig. 3

Claims (1)

[Claims] It includes a reverse direction motion command table that stores reverse direction motion commands in one-to-one correspondence with forward direction motion commands, and a forward direction motion execution order record table that stores the execution order of forward direction motion commands that operate in the forward direction according to a program. , selecting and executing a reverse direction operation corresponding to the forward direction operation from the above-mentioned reverse direction operation command table in the reverse order of the forward direction operation stored in the forward direction operation execution order recording table in response to the reverse direction operation command; A programmable controller with a reverse order operation function. ′