JPH02311251A - Switching method for machine control system - Google Patents

Abstract

PURPOSE:To make full use of existing process machine and line by incorporating a control procedure by which a signal responding to centralized control direction from an upper management device is output, into a machine control device of each station, when an existing centralized control system is switched to a distributed control method. CONSTITUTION:A machine controller 12 in which a control procedure is preliminarily built, a TAG controller 13 that reads numerical information from a TAG equipped in a pallet, a CNC unit 14 that executes numerical control of a machine, and a servo controller 17 are provided, in which a connection of an existing facility is cut as indicated with a cross, each station is separated from an upper management device, namely, CPU and TSNC, and is reduced to an independent situation. While all of the stations are to be made independent, by incorporating a sequence by which a signal responding to centralized control direction that is sent from the upper management device through an existing MTC is output, into the machine controller 12, sound operation of the control system is maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for switching a system configured to centrally control a plurality of machines to a distributed control system.

[Prior Art] As an example of a system in which a plurality of machining stations are centrally controlled by a host management device, an automatic control valve body adjustment system shown in FIG. 6 (Al tB) is known. This machine performs direct numerical control (DNC) using a computer, and has eight processing stations (stn, 1 to s).
It is a closed-loop transfer machine system consisting of tn, 8) and 12 machine tools.

This system employs a centralized control method in which one computer (CPU), which is a higher-level management device, performs NC for all machine tools and also manages the entire system. The system uses a computer to monitor the movement of workpiece processing pallets through a simulation based on a conveyor model, and a time-shared numerical controller (TSNC).
and a machine control device (MTC) to control each machine tool.

[Problem to be solved by the invention] However, once a problem occurs in the above-mentioned centralized control system, the conveyor model and the actual movement of pallets may not match, and confirmation and restoration work is required. The problem is that it takes a lot of time.

Therefore, a system is being considered in which the control function is decentralized so that each station can function independently as a computer numerical control (CNC) device. However, in order to modify existing equipment in this way, the problem is that a new system must be built in a different location and replaced entirely, or the work must be carried out with the existing equipment stopped for a long period of time. was there.

Therefore, an object of the present invention is to provide a system switching method that can effectively utilize existing centrally controlled processing machines and lines, minimize new capital investment, and configure a system with decentralized functions. [Means for Solving the Problems] The present invention is a method for switching a system configured such that a plurality of machining stations are centrally controlled by a first-level management device to a distributed control system, in which each station is
A machine control device incorporating a control procedure in advance, a reading control device reading information from an information storage means attached to a pallet moving between each station, and a reading control device reading information from the reading control device under control of the machine control device. A numerical control device is provided to control the processing machine, and each station is made independent by being separated from the upper management device, and until all stations are made independent, the machine control device responds to centralized control commands from the upper management device. It is characterized in that the control method of a plurality of machining stations is sequentially switched to distributed control by outputting a signal.

[Function] According to the present invention, each station is provided with a machine control device, a reading control device, and a numerical control device, and then is separated from the first-rank management device to independently control the processing machine. It becomes like this. In that case, under the control of the machine controller, a reading controller reads information from an information storage means attached to a pallet moving between each station, and a numerical controller controls the processing machine according to the information.

On the other hand, non-independent stations are centrally controlled by a higher-level management device. Until all stations are made independent as described above, old and new stations with different control methods (centralized and decentralized) coexist, but a signal is output to the machine control device in response to a centralized control command from the upper management device. By incorporating control procedures, it is possible to create a state in which the entire system, in which old and new control methods coexist, is operating in a healthy manner.

Therefore, while existing centralized control system equipment coexists,
It becomes possible to switch control methods for multiple machining stations without stopping operation.

[Example] FIG. 1 shows a valve processing distributed control system as an example of a system switched to a distributed control method according to the present invention.

This is the main control unit 1 including the FA Combuque 10.
1 centrally manages a plurality of processing stations ST#1 to ST#8, but control functions are distributed to each station. Therefore, each station is equipped with a machine controller 12 that incorporates processing procedures in advance, and a storage device (T D
- A reading control device (TAG controller) 13 that reads information from a suitable sensor 135 (referred to as TAG)
and 1 read control device 1 under the control of machine control device 12
A numerical control device (CNC unit) 14 is provided to control the processing machine according to information sent from the pallet 20, and processing is performed independently according to information from the TD-TAG attached to the pallet 20. Note that the machine controller 12 is connected to the line control device 16 of this system via a machine control panel 15 provided at each station.

FIG. 2 shows the details of construction at each station as an example of a method for switching an existing centralized control system (FIG. 6) to a distributed control system (FIG. 1).

First, the machine controller 1 has a control procedure installed in advance.
2 and the CNC unit 14 that numerically controls the machine are connected to the machine tool 21, while the TAG attached to the pallet 20
A TAG controller 13 that reads numerical control information from a tag is connected to the machine controller 12.

In addition, since the machine tool 21 is numerically controlled by the CNC unit 14 via a servo mechanism, the existing machine control device (
Replace the electro-hydraulic pulse smoke (EHPM) 22 of the machine tool connected to the MTC with the ACC servomorph 2, and connect this to the servo controller ]7.

Note that the existing MTC has a pulse distributor (IP
machine tool 21 in response to a pulse train manually inputted via L).
The digital input/output section (D I
It is equipped with a command control function that performs operations according to control commands between the robot and included (IRT).

At each station, the machine controller 12, TAG controller 13, CNC unit 1
4 and the servo controller 17, each station is separated from the upper management device, that is, the CPU and the TSNC, and becomes independent by cutting the connections of the existing equipment as shown by the x marks.

However, until all stations are made independent, the control system can operate properly by incorporating a sequence in the machine controller 12 that outputs a signal in response to a centralized control command sent from a higher-level management device via the existing MTC. maintain the current state. Then, the existing CPU, TSNC, and MTC are removed after all stations are switched.

On the other hand, the conveyor 24 that moves pallets between each station is controlled by a pallet conveyor controller (FIG. 6(B)) including a conveyor control panel 25. Instead, a common line control device 16 is provided for each station. This control device 16 is connected to the machine controller 12 via the machine control panel 15 of each station as described above. As a result, the existing main control panel 26 for controlling line operation is finally removed.

In the control system shown in FIG. 1, functions are decentralized by changing the above-described centralized control method to a distributed control method, thereby facilitating subsequent changes and expansion of the system and increasing the reliability of the system.

In addition, the information processing system with new functions is a network of the main control unit 11 including the FA computer IO, each station #l to #8, and the upper information system, and allows for centralized management of management information. making it possible. The status information of each station is monitored in real time, and a production plan can be created in conjunction with the production management information of the host information system.

The flow of information within the lines in the system of FIG. 1 is as follows.

Production information (NC data, tool information, model number, etc.) is transmitted from the FA computer 10 to the TAG controller 13 in synchronization with the work at the loading station 31, which will be described later. The data written to the tag at the loading station 31 is transferred to the processing station 3 along with the pallet 20.
2 (see Figure 3).

At each processing station, the data is read by the TAG controller 13 at the standby position before loading, the NC data is processed by the CNC unit 14, and the tool information is processed by the tool management sequence of the machine controller 12. etc.

The machine controller 12 informs the operator of workpiece information such as the model number and the like in a timely manner via the display terminal 18 such as a CRT, and when a change occurs, the operator is instructed to perform off-machine setup in advance and Try to minimize the associated losses.

A similar process is repeated at each of a plurality of processing stations (in this case, #1 to #8), and the pallet moves while integrating objects and information. Meanwhile, the status information of each station can be collected in real time.

When changing the machine control system from a centralized control system to a distributed control system as described above, the problem in system construction is how to automatically recognize the machining information of the workpieces loaded on the pallet at each CNC station. death,
The question is whether to instruct the CNC device and stage change display device. Therefore, ID-TAG is used in this embodiment.

FIG. 3 is an explanatory diagram of an automatic pallet recognition mechanism using TD-TAG. Automatic pallet recognition is performed by using the aforementioned TAG controller 13 at each of the loading station 31 and the processing station 32, by writing to and reading from the tag attached to the pallet.

As shown in FIG. 4(A), the loading station 31 includes an FA computer IO, a work certification operation panel 33 connected to this, a monitor 34, and a TAG controller 1.
It consists of 3. Here, the FA computer 10 performs the TAG write operation shown in FIG. 4 (Bl).

First, the dimensions of the workpiece are certified, and after checking, data is written to the tag 19 via the TAG controller 13. Specifically, after initializing the data area of the TAG controller 13, data is transmitted and written to the tag 19.

Next, the FA computer 10 reads the data from the tag I9 again and checks the data. If there is an abnormality, it performs a predetermined abnormality process, and if it is normal, it writes and checks the next data. When data transmission is completed successfully,
The pallet 20 is transported to the processing station 32.

On the other hand, the processing station 32 includes a machine controller 12 and a CNC connected thereto, as shown in FIG.
Unit 14, display device 18, TAG controller 13
and a machine control panel 15. Note that a limit switch 35 for detecting a standby position before pallet loading is connected to the machine control panel 15. At the processing station 32, the machine controller 12 performs the TAG reading operation shown in FIG.

First, it is checked whether the limit switch 35 is ON or not, and when it is ON, that is, the standby position before pallet loading is detected, it is checked whether the TAG controller 13 is ready. The data is read from the tag 19, and when it is completed, the data is checked for errors. As a result, if there is a data error, read the data after checking the readiness of the TAG controller 13 again.6 If there is no data error, check whether it is possible to send to the CNC unit 14, and then read the data from the TAG controller 13. Send the NC program to unit 14. At the same time, a stage change display signal is sent to the display terminal 18, and tool information and workpiece information necessary for the next machining workpiece are displayed on the screen.

Based on this information, the operator can perform changeover work in advance if necessary.

When the transmission of the NC program to the CNC unit 14 is completed, the TAG controller 13 is reset and the pallet 2
0 to the next station.

In an embodiment, a communication network as described above and an I.
Data carrier system (data-driven control) using D-TAG realizes information aggregation and function decentralization. Data-driven is a method in which machining information for a workpiece is attached to the workpiece, and the machine tool performs machining according to the information contained in the workpiece.

In the above embodiment, the tag 19 attached to the pallet 20 serves as a recording medium for information accompanying the workpiece. That is, the processing information and its accompanying information, which were controlled by the conventional centralized method, are conveyed by integrating the object and the information using the ID-TAG.

Therefore, each machine only needs to perform sequence operations from loading the workpiece to unloading it using an individual sequence control device (machine controller). Carry out the work.

” simplification of control becomes possible. In addition, when a conventional machine control device (MTC) coexists, the machine controller generates a signal in response to centralized control information from the upper management device, creating a state in which the control system is configured in a healthy manner. , old equipment can coexist.

The above-mentioned change from the centralized control method to the distributed control method is a change in the basic functions of the system, and the general idea is that it is executed all at once. The range (stations) was gradually narrowed and replaced with a distributed control system. In other words, during the period from the start to the completion of the changeover work, the machine tools at multiple processing stations are controlled (some using the old centralized control system and others using the new distributed control system. The factors that enable sequential switching are the old and new
One example is that there is no need to guarantee synchronization of control/management information or timing between two control systems.

Although the embodiments have been described above, the present invention is not limited thereto. For example, the system switched according to the present invention is not limited to the control valve addition system as shown in FIG. 6, and the distributed control system after switching is not limited to that shown in FIG. 1. Also,
As the information storage means attached to the pallet, I
It is not limited to D-TAG, but may be a bar code or any other device that can write/read data.

[Effects of the Invention] As described above, the present invention utilizes existing centralized control system equipment to sequentially switch to distributed control, so the following effects can be obtained.

■ Conventionally, when switching control methods, a huge amount of time was spent completing the software for the entire system and then debugging it, but according to the present invention, it is now possible to partially construct the system. The time required for software development, including debugging time, can be significantly reduced.

■The sequential switching method of the present invention can be applied to system expansion and modification, and enables flexible line changes.

■CNC conversion work can be carried out at each station without stopping production using the existing DNC line.

■Capital investment can be kept to a minimum and existing equipment can be used effectively.

4 Brief explanation of the drawings Figure 1 is a diagram showing an example of a distributed control system, Figure 2 is a diagram showing a switching method at each station of a centralized control system, and Figure 3 is a diagram showing an automatic pallet recognition mechanism using TD-TAG. Explanatory diagram, Figure 4 (Al and fB) is a hardware configuration diagram of the loading station and a flowchart showing the procedure for writing to the tag, Figure 5 fAl and (B) is a hardware configuration diagram of the processing station and reading from the tag Flowchart showing the procedure. FIG. 6(A) is a schematic plan view showing an automatic control valve main body adjustment system as an example of a centralized control system, and FIG. 6(A) is a block diagram of the system.

IO...FA computer, 11...Main control unit, 12...Machine controller, 13...TAG controller, 14...CNC unit, 15...Machine control panel, 16--line control device, 17--servo controller, 18--display device, 19--tag, 20--
...Pallet, 21...Machine tool, 24...
- Conveyor, 25... Conveyor control panel, 26... Main control panel, 31... Loading station, 32 - Canis station.

1 just

Claims (1)

[Scope of Claims] A method for switching a system configured such that a plurality of machining stations are centrally controlled by a host management device to a distributed control method, comprising: a machine control system in which a control procedure is pre-incorporated in each of the stations; a reading control device that reads information from an information storage means attached to a pallet that moves between stations; and a numerical value that controls a processing machine according to information sent from the reading control device under control of the machine control device. A control device is provided, each station is separated from the upper management device and made independent, and the machine control device outputs a signal in response to a centralized control command from the upper management device until all the stations are made independent. A method for switching a machine control system, comprising sequentially switching the control method of the plurality of machining stations to distributed control.