JPH09101809A - Bit unit sequencer system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bit unit sequencer system capable of largely reducing the number of required wires, easily corresponding to a change in a sequence and dispersing danger of disabling the control of an equipment when a power supply is lost or failed. SOLUTION: Bit sequence units 1a to 1d having a logic operation function for storing its own state and updating the state by the states of other units, input units 2a, 2b for fetching signals from the external through a terminal board T, output units 3a, 3b for fetching data from the units 1a to 1d and sending signals to the external equipment through the terminal board T, a programming device I/F unit 4 having a function for monitoring respective units and a function for setting the input and change of operation equations for respective units and data transmission order are connected through a transmission line 5 and a power supply line for respective units is divided into each controlled equipment unit and wired.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for replacing a hard sequence circuit using a mechanical relay with a software sequence using a sequencer (programmable controller: PC), and more particularly to a bit-unit sequencer system.

[0002]

2. Description of the Related Art Currently, when a sequence is formed, it is generally realized by a relay sequence circuit using a mechanical relay or a sequence program on a programmable controller.

FIG. 7 shows an example of a relay sequence circuit. Normally, a relay sequence circuit consists of a terminal block for exchanging signals between the relay and the outside, and wiring between the relays and for connecting the relay and the terminal block. These parts are one or more boards. Is housed inside.

In the relay sequence circuit, when a complicated and large-scale control circuit is assembled or the relay and the relay sequence circuit are not used, the sequence is realized by replacing it with a sequence program on the programmable controller. In the sequence program, not only the on / off state, but also numerical processing and conditional branching are possible, so very complicated control can be solved.

However, even in a control system using a programmable controller, a simple operation / stop circuit by a relay sequence circuit is also used as a countermeasure against the fact that the device cannot be controlled at all due to the failure of the programmable controller (backup). circuit).

[0006]

When the relay sequence circuit is used, the following problems occur. (1) To carry out large-scale and complicated control, much time and effort are required for designing, assembling, manufacturing, and testing, and the manufacturing period becomes long. Circuits are typically different from time to time, so almost every relay sequence circuit needs to be individually designed and tested.

(2) When making changes or corrections, it is not easy to change the wiring one by one. It is not easy because the wire is tightened to the terminal block with wrapping or screwdriver. In many cases, it is necessary to add relays or modify the control panel.

(3) The device (control panel) becomes large.

If the relay sequence circuit is replaced with a programmable controller and the program is realized by a sequence program in order to make up for the drawbacks (1) to (3), there are the following problems. (4) When the programmable controller has a plurality of devices under control, a plurality of devices cannot be controlled due to the failure of one programmable controller, and the independence of the control circuit cannot be maintained.

(5) On the programmable controller, the circuit for performing the independent operation can be realized by a small program of about 10 or more in terms of the relay circuit. In the existing small capacity programmable controller, several hundred to ten
About 100 program steps can be input. Therefore, there is a lot of waste even if the independent operation sequence is composed of independent small-capacity programmable controllers.

The present invention has been made in view of the above points, and an object thereof is to significantly reduce wiring required and
It is an object of the present invention to provide a bit-by-sequencer system that can easily deal with sequence changes and that has a distributed risk of device control being disabled when power is lost or fails.

[0012]

[Means for Solving the Problems]

(1) According to the present invention, a sequencer for controlling a device by a sequence has a logical operation function of storing its own status and updating the status using the status of another unit, and transmits data in a predetermined order. Data from the bit sequence unit, a plurality of bit sequence units, a plurality of input units that receive signals from the outside through the terminal block, perform an operation in the state of other units, and transmit data in a predetermined order Has a function to calculate the output calculation formula and add the output condition to the external output, and monitor the status of each output unit and the output unit that sends signals to the external device in a predetermined order via the terminal block. In addition, each unit is provided with a programming device for inputting and changing arithmetic expressions and setting the data transmission order. And a programming device are connected via a transmission line, the power supply line of each unit is divided and wired in units of controlled devices, and the programming device performs an operation of sending an operation command to each unit in a predetermined order. Repeatedly, each unit only transmits data at the time of the first operation command, and at the time of the second and subsequent operation commands, performs data transmission after the arithmetic processing. (2) The predetermined order is It is characterized in that the order is in accordance with the identification number given to each unit.

(3) Since only the wiring of the power supply line and the transmission line is required, the hardware circuit can be easily designed and manufactured. The sequence is changed only by changing the logical operation expression in each unit by the programming device. Since the power supply line is divided and wired for each device to be controlled and the operation is performed for each bit, the device control is limited to only the device concerned due to the loss of the power supply or the unit failure.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In the present invention, in order to solve the above-mentioned problems, a relay sequence circuit such as an independent operation circuit is replaced with a 1-bit sequencer. That is, as shown in FIG. 1, as the unit of the 1-bit sequencer, four kinds of units, that is, bit sequence units 1a to 1d, input units 2a and 2b, output units 3a and 3b, and programming device I / F unit 4 are prepared. These units are connected by a transmission line 5 in a panel unit or a row panel unit. 6a and 6b are terminating resistors. Further, the power supply line is laid by dividing the power supply in units of controlled equipment. As a result, it is possible to minimize the stoppage of the equipment due to the power loss.

The bit sequence units 1a-1d
The inside of is configured as shown in FIG. Inside is transmission line I /
F, a control unit CTR for controlling the whole, a memory unit 10,
The operation unit (bit operation unit LU) is roughly divided. The memory unit 10 includes an identification number ID of its own unit, an identification number of a unit that transmits data immediately before itself (previous unit identification number) PID, an own unit status memory (1or0) BM1, and another unit status memory (1or
0) BM2, which has a logical operation formula for updating its own state with the state of another unit.

The transmission line I / F receives the identification number and data of another unit sent out on the transmission line 5, the logical operation formula from the programming device I / F unit 4, and sends out its own identification number and state. It is an interface unit for doing.

Input units 2a and 2b, output unit 3
Reference numerals a and 3b are units for the bit sequencer system to exchange signals with the outside, and both have a terminal block T for connecting an external signal, as shown in FIGS.

The input units 2a and 2b are a calculation unit (bit calculation unit LU) for calculating a signal from the outside in a state of another unit, a control unit CTR and the memory unit 10 of FIG.
It has a memory section 20 similar to. Output unit 3
a and 3b are also provided with an operation unit (bit operation unit L so that conditions such as interlock can be added when output to the outside.
U), a control unit CTR and a memory unit 30 similar to the memory unit 10 of FIG.

As shown in FIG. 5, the programming device I / F unit 4 is connected to a programming device 40 for monitoring the state of each unit, inputting / changing an arithmetic expression, and setting the data transmission order. Is configured.

It should be noted that the signals of one point and one point of the terminal block T of the input units 2a and 2b and the output units 3a and 3b can be provided with an identification number ID. Further, the power supply line is laid by dividing the power supply in units of controlled equipment. As a result, it is possible to minimize the stoppage of the equipment due to the power loss.

[0021]

EXAMPLE Next, the operation of the sequencer configured as described above will be described with reference to the time chart of FIG. Each unit sends its own identification number and its own status (1 or 0) on the transmission path. The order in which the units send the calculation results can be designated by the programming device 40, and each unit also stores the identification number of the unit that sends data before itself (referred to as the previous unit identification number). .

When a certain unit sends its own identification number and the operation result, among the other units, the unit containing the identification number of the unit that sent the data in the arithmetic expression is
Capture that data. Further, the unit whose previous unit identification number matches the transmitted identification number transmits the data next to the unit which has just transmitted the data. In this way, data is transmitted in sequence.

The front unit identification number of the first unit to be activated is the identification number of the unit which transmits the data last. By this, after sending the data of the last unit,
Data can be sent again from the head unit.

For activation immediately after power-on, an appropriate unit is selected, an activation command is given from the programming device 40, and data is transmitted from that unit. Calculation of the arithmetic expression is performed from the second data transmission. Prior to the second data transmission, each unit calculates an arithmetic expression using the states of the other units acquired during the previous data transmission, updates its own state, and then transmits the data.

The input units 2a and 2b calculate signals from the outside in the state of other units and send data. The output units 3a and 3b calculate output arithmetic expressions based on the data from the bit sequence units 1a to 1d. Similar to the bit sequencer, the output units 3a and 3b output signals to the outside immediately before the second and subsequent data transmissions.

[0026]

As described above, according to the present invention, the following excellent effects can be obtained. (1) Greatly reduce wiring, hardware circuit design,
Manufacturing becomes easier. Compared to the case where the same sequence is built with a relay sequence circuit, only the wiring of the power supply line and the transmission line is required, and the wiring from the terminal block does not require a bundle.

(2) Since the number of units that can be referred to by the unit status signal is not limited, the number of contacts in the relay sequence circuit, that is, the number of relays can be reduced.

(3) It is very easy to change the sequence. The sequence can be changed only by changing the in-unit logical operation formula with a programming device. Even if the unit is expanded, if there is mounting space, only the power supply line and the transmission line should be wired.

(4) The time required for the test can be greatly reduced. Since the number of wires and bundles is reduced, the time required for checking the wires can be significantly reduced.

(5) There is no waste even if an independent operation circuit is assembled. Since it suffices to prepare as many units as necessary, it is possible to avoid the size of the program memory and the size of the actual program being remarkably different from each other as in the programmable controller.

(6) The risk dispersion due to unit division is included. That is, since the power supply line is branched for each device to be controlled and the operation is performed for each bit, it is impossible to control the device due to loss of power or failure of the unit.
It can be limited to only the device.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an entire system configuration according to an embodiment of the present invention, and FIG. 1 (b) is an explanatory diagram showing an execution order of data transmission of each unit.

FIG. 2 is a configuration diagram showing a bit sequence unit of the present invention.

FIG. 3 is a configuration diagram showing an input unit of the present invention.

FIG. 4 is a configuration diagram showing an output unit of the present invention.

FIG. 5 is a configuration diagram showing a programming device I / F unit of the present invention.

FIG. 6 is a time chart for explaining the operation of the present invention.

FIG. 7 is a configuration diagram showing an example of a conventional programmable controller and a relay sequence circuit.

[Explanation of symbols]

 1a to 1d ... Bit sequence unit 2a, 2b ... Input unit 3a, 3b ... Output unit 4 ... Programming device I / F unit 5 ... Transmission line 10, 20, 30 ... Memory unit 40 ... Programming device

Claims (2)

[Claims] 1. A sequencer for controlling a device by a sequence, which has a logical operation function of storing a self-state and updating the state by using a state of another unit, and transmitting a plurality of bits in a predetermined order. A sequence unit, a plurality of input units that receive signals from the outside via the terminal block, perform operations in the state of other units, and transmit data in a predetermined order, and capture data from the bit sequence unit. It has the function of calculating the output calculation formula and adding the condition to the external output.
An output unit that sends signals to external devices in a predetermined order via the terminal block, and programming that monitors the status of each unit and inputs, changes, and sets the data transmission order for each unit A device is provided, the respective units and the programming device are connected via a transmission line, the power supply line of each unit is divided and wired in units of controlled devices, and the programming device is arranged in each unit in a predetermined order. The above-mentioned units repeatedly perform the operation of transmitting the operation command to the first unit, and each unit transmits only the data when the first operation command is issued, and transmits the data after the arithmetic processing at the second and subsequent operation commands. Unit sequencer system. 2. The bit sequencer system according to claim 1, wherein the predetermined order is an order according to an identification number given to each unit.