JPS61214956A - Scheduling method - Google Patents

Abstract

PURPOSE:To permit the scheduling in a small-sized system by memorizing each file for process table, machine condition, jig, and tool, and inputting the working instruction file for each order, and preparing the schedule list for each machine by using each file. CONSTITUTION:A machine tool used for working parts and the tool and the jig which are to be used are obtained from a process table MPT, having the part name specified by each order and the process order as key words. It is judged from a machine condition file MCF if the machine tool is in work-enable state or not. Further, it is judged from the jig and tool files if the jig and tool can be used for the working for the specified part. When the machine tool is in working-possible state, and also the jig and tool can be used, a schedule list for allowing the machine tool to execute the working for the ordered part is prepared. Therefore, instruction for work can be simply carried-out, and the fine scheduling in a small-sized system for each machinery can be prepared.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a scheduling method, and particularly to a scheduling method in a factory automation system (FA system).

<Prior art> In addition to providing a large number of processing cells including numerically controlled machine tools and robots, a logistics system including a jig room for storing jigs and tools, an automated warehouse for storing workpieces and processed parts, automatic guided vehicles, etc. An FA system has been put into practical use in which a central management system controls the operation (scheduled operation, logistics control) of these processing cells, tool rooms, and logistics systems according to the production schedule.

In such conventional FA systems, the central management system receives a detailed production schedule list for each machine tool from the host computer, and controls the operation of the machine tools in accordance with the production schedule list. In other words, conventionally, the host side issues detailed instructions necessary for creating a production schedule list, and creates a detailed production schedule for each machine tool with the help of a large host computer.

<Problems to be solved by the invention> However, with this conventional method, there are problems in that it is not easy to give instructions for creating a production schedule, and moreover, a large computer is required, which increases the cost of the system. Ta.

Accordingly, an object of the present invention is to provide a scheduling method that allows even a small computer system to easily perform scheduling and also allows work instructions to be easily issued.

Means for Solving the Problems〉 The scheduling method in the FA system of the present invention consists of (1) determining the order of steps necessary to machine each part, and the machine tools and programs used for each process; Process table including numbers, jigs and tools used, and machining time, (
2) Machine condition file containing data on whether each machine tool is currently machinable, (3) Jig file containing data on each jig indicating whether the jig is in use, (4) Tool storage status For each order, a work instruction file containing at least a part name, machining quantity, and process order is input, and a machine schedule list is created using each of these files.

Using the part name and process order specified by each order as keywords, the machine tool used to process the part and the tools and jigs to be used are determined from the process table, and whether or not the machine tool is ready for processing is determined. It is determined from the machine condition file, and whether the jig and tool can be used for machining the specified part is determined by referring to the jig file and the tool file. If jigs and tools are available, a schedule list is created for causing the machine tool to process the parts of the order. When a machine tool is to process the parts specified by the order, the machine condition file is updated so that the machine tool cannot be used until the machining is completed, and the jig file is updated. However, if it is necessary to replace a tool with another machine tool, a replacement instruction list is created and stored.

<Embodiment> FIG. 1 is a schematic explanatory diagram of the present invention, and FIG. 2 is an overall block diagram of an FA system to which the present invention can be applied. In Figure 2, 101 is the central management system, 102 is the local management system, and 102 is the local management system.
Area network (LAN), 103 is the tool room, 104 is the logistics system, 105.10B, 107...
・respectively are cell controllers, 1) 1. 1) 2,...
... is a processing cell and 121 tool carrier.

The central management system 101 includes (a) a main computer 101a that controls the operation of each processing cell, tool room, and logistics system according to a created production schedule; and (b)
a subcomputer 101b that creates a schedule list for each machine using the input work instruction file;
) 101c is a large-capacity program file unit that stores a large number of programs, etc.

A process table MP71 and a machine condition file MC shown in FIG. 1 are stored in a memory (not shown) of the main computer 101a.
F, a jig file JGF, and a tool file TLF indicating the accommodation status of tools are stored. Subcomputer 10
1b receives each file from the main combination coater,
A schedule list 5CHL for each machine, a tool replacement instruction list TLCL, etc. are created and outputted from these files MPT-TLF and a work instruction file OCF that is input separately.

The work instruction file OCF includes a large number of orders, and each order includes at least (al order number, (b) part name, (c1 machining order (1 order), and fdl machining quantity) as shown in Figure 3. Here, the part name is the name of the part you want to machine in the FA system. Also, the machining order (in order of 1) is the name of the part you want to machine in the FA system. (different machine tools) are required, so this indicates the number of the machining process.

As shown in Fig. 4, the process table MPT is created for each part (in Fig. 4, the process table with part name A123 is shown).
The order of machining processes that can be executed in the A system (referred to as machining order or 1 order) (bl Name of the machining process (lathe machining, milling machining, grinding machining, etc.) in each route and the machine tool used for the machining process (c) Program number (dl) used for processing the process
The jig number used for machining the process, (a) Information on the tool used for machining the process (fl includes the machining time required for machining the process. Note that the FA system uses the second , 3rd, 5th, and 6th steps are described as being able to be executed in the order of steps.

As shown in Figure 5, the machine condition file MCF contains (a + machine name, (bl cell name, (c) failure flag, (d) testing flag (e) (historical flag (fl Contains the machining end time.The failure flag, testing flag, and in-use flag are +1 if they are in failure, testing, or in use, respectively.
)1) becomes. Further, the machining end time is the end time of the assigned part machining.

The jig file JGF is small (including the (al jig number and (bl in-use flag), and if the jig is in use, the in-use flag is 1) 1 for each jig.

(↓Me 2,000 #White tool file TLF contains at least (a) the tool numbers of all tools stored in the tool room, their storage positions in the tool room, and (bl) the tools of the tools stored in the magazine of each machine tool. Contains the relationship (pot information file) between the number, magazine number, and pot number (storage position).

The scheduling method according to the present invention will be explained below with reference to the flowchart shown in FIG.

When a work instruction file OCF (FIG. 1) containing a large number of orders is input from a data input device such as a keyboard, the processor of the subcomputer 101b executes scheduling processing by the following processing.

(1) First, the control start time of the FA system on day - (current time ta) is set.

(2) Next, set 1→1.

(3) After receiving the order, take out the first order from the work instruction file OCF.

(4) Part names and processing order included in the first order (1
The machine tool used for machining the part is recognized from the process table MPT using the keyword "order)".

(5) It is checked with reference to the machine condition file MCF whether or not there is a machine tool capable of machining the parts among the recognized machine tools for machining the parts. It is assumed that processing is possible when the failure flag, testing flag, and in-use flag are all "O".

(6) If there is no machine tool capable of processing, step +
Execute the process from II onwards, and if there is a machine tool that can process the part, it will recognize the jig number used for machining the part in the same way as step (4), and check whether the jig can be used by checking the jig file JGF. Browse and check.

Note that if the in-use flag of the corresponding jig is "O", it can be used.

(7) Next, the tool used for machining the part is recognized, and then the tool file (pot information file) T corresponding to the magazine of the machine tool found in step (5)
Refer to LF to check whether all the tools used are installed in the magazine.

(8) If there is a tool that is not installed, refer to the tool file corresponding to the tool room to check whether the tool exists in the tool room.

(9) If the tool does not exist in the tool room, refer to the pot information file of another magazine to check whether the tool is installed in the other magazine.

(1) All the tools used are installed in the magazine of the machine tool when checking step (7), or tools that are not installed are present in the tool room when checking step (8), or when checking step (9) If the magazine is loaded in another magazine, the processor checks whether the workpiece used to process the part exists in the warehouse or has been carried into the machine tool. Incidentally, if the corresponding tool is not mounted in any other magazine in step (9), the processing from step (1) onwards is executed.

(1)) If a work exists, the processor calculates the machining quantity N specified in the i-th order, the machining time ΔT required for machining one part obtained from the process table MPT, and the current time ta.
The machining end time te is calculated using the following formula % formula %. Incidentally, if the process table MPT includes setup time and removal time, the machining end time is calculated in consideration of these setup time and removal time.

(!Next, the processor sets the in-use flag of the corresponding machine tool in the machine condition file MCF to ``1'', and sets the machining end time to te obtained in step (1)).
Update with.

(131 Also, the processor updates the in-use flag of the corresponding jig in the jig file to n1''.

(14) Furthermore, the processor creates a tool replacement instruction list (stores the tool replacement instruction information in the built-in memory).

Note that the tools installed in the magazine of the machine tool determined in step (5) cannot be replaced thereafter.

Figure 7 is an example of a tool replacement instruction list in which tool replacement instruction information is printed out as a list, the first column shows the number of tools to be replaced, and the second column shows the magazine number of the magazine in which the tools are to be stored.
0, the third column is the pot number indicating in which pot of the magazine the tool is stored, the fourth column is the tool number of the old tool stored in the pot of the magazine, and the fifth column is The tool number of the new tool to be stored in the pot of the magazine is printed.

(After this, the processor creates a machine schedule list 5C) (L (stores the machine schedule in the built-in memory). In other words, the machine tool determined in step (5) is specified by the i-th order. A schedule for processing Nt! of the processed parts is registered in the memory. Figure 8 shows schedule list 5 for machine name MK6.
It is an explanatory diagram of CHL, and includes a cell name and a machine tool name, as well as several order numbers, part names, the number of machined parts, etc.

(1! After creating the schedule list, 1+1→i
Take one step forward.

(1η) Next, the processor checks whether the allocation of all orders has been completed. If the allocation of all orders has not been completed, the processing from step (3) onward is repeated.

(If the allocation of all 1 order is completed, the following formula ta +
A-+ta causes A minutes to elapse from the current time.

(IIJ Next, the machine condition file MCF is referred to to check whether there is a machine tool whose machining end time has passed.

(To) If there is a machine tool that has passed, set the in-use flag of that machine tool to nO''.

(21) Next, it is checked whether the FAilJ end time on -day has arrived. If not, step (
2) The following process is repeated to allocate orders that have not been allocated to machine tools until now, and if the FA control end time has come, the scheduling process is ended.

Note that, in order to simplify the explanation, the above description has been made on the assumption that if there are workpieces, there will always be workpieces of the instructed machining quantity, but the number of workpieces may also be taken into consideration.

Also, in the same way, we have explained that all the parts of quantity N specified in one order can be machined with one machining Ia reduction, but if N・ΔT is larger than the FA control time in one day, -
The machine tool may process the quantity that can be processed in a day, and the rest may be processed by another machine tool.

<Effects of the Invention> According to the present invention, for each part, (a) the order of steps necessary to process the part, and (b) the machine tool used in each step, the machine number, and the jig used. A process table including the tools used and machining time is memorized, and a work instruction file containing at least the part name, machining quantity, and process order is input for each order, and the part name and process order specified by each order are input. Since the machine tool to be used for parts processing is determined from the process table using the keyword, and the machine tool determined is scheduled to process the part specified by the order, work instructions can be easily given. Even with a small system, a detailed machine-side schedule can be created simply by inputting a rough schedule.

[Brief explanation of drawings]

Figure 1 is a schematic illustration of the present invention, Figure 2 is a configuration diagram of an FA system to which the present invention can be applied, Figure 3 is an illustration of a work instruction file, Figure 4 is an illustration of a process table, and Figure 5. 6 is an explanatory diagram of the machine condition file, FIG. 6 is a flowchart of the processing of the scheduling method of the present invention, FIG. 7 is an explanatory diagram of the tool change instruction list, and FIG. 8 is an explanatory diagram of the machine side schedule list. . 101...Central management system, 101b...Subcomputer, OCF...Work instruction file, MPT...Process table, MCF...Machine condition file, JGF...Jig file, TLF...Tool file

Claims (4)

[Claims] (1) In a scheduling method in an FA system that controls the operation of each machine tool according to a production schedule, for each part, (a) the order of steps necessary to process the part, and (b) the machine tools used for each step. A process table including the program number, jig used, tool used, and machining time is memorized, and a work instruction file containing at least the part name, process order, and machining quantity is input for each order, and specified by each order. A machine tool to be used for machining the part is determined from the process table using the part name and process order as keywords, and the machine tool is scheduled so that the determined machine tool processes the part specified by the order. scheduling method. (2) In addition to the process table, (a) a machine condition file containing data on whether or not each machine tool can be processed at the current time, and (b) indicating for each jig whether the jig is in use or not. A machine tool that stores a jig file containing data, and (c) a tool file that indicates the storage status of tools, and uses the part name and process order specified by the order as keywords to process the part from the process table. determines the tools and jigs to be used, determines from the machine condition file whether the machine tool is ready for machining, and determines whether the jigs and tools can be used to process the specified part. is determined by referring to the jig file and tool file, and if the machine tool is ready for machining and the jig and tool can be used, the machine tool is made to process the parts of the order. The scheduling method according to claim (1), characterized in that scheduling is performed. (3) When making a machine tool process the identified part, update the machine condition file and update the jig file so that the machine tool cannot be used until the process is completed. Claim No. 2 (2) characterized in that
) Scheduling method described in section. (4) The scheduling method according to claim (3), further comprising the step of creating and storing a replacement instruction list when it is necessary to replace the tool with another machine tool.