JPH03221340A - Management of tool - Google Patents

Abstract

PURPOSE:To efficiently perform a tool exchange by setting the zone of the magazine inside based on the high and low of a tool exchange level and exchang ing with a designated tool in the order from the tool stored in the low zone of the exchange level of this magazine inside, in the case of there being no designated tool in the corresponding zone of this magazine inside. CONSTITUTION:A tool exchange level in set on each tool based on the repeated ly usable degree and also the magazine inside of an ATC (Automatic Tool Changer) device 4 which stores these tools is set in its zone based on the high and low of the tool exchange level. Then, the specific processing is performed by exchanging with the tool designated by a robot 6, in the order from the tool stored inside the zone of the low exchange level of this magazine inside, in the case of there being no designated tool in the corresponding zone of this magazine inside. Consequently, the tool of the magazine inside is automatically selected and recomposed to the optimum tool layout according to the difference, etc., of the kind and working content of a processing work.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a tool management method in a processing machine such as a machining center equipped with an automatic tool changer.

An example of an automatic tool changer (hereinafter referred to as an ATC device) provided in a conventional numerically controlled (hereinafter referred to as NC) processing machine is one described in, for example, Japanese Patent Laid-Open No. 59-69241.

This ATC device has a plurality of tool holding devices with different diameters on the outer periphery, and is equipped with a disk-shaped magazine that allows each of these tool holding devices to hold a tool, and the tools held by the tool holding device, Discrimination information for distinguishing the diameter of the tool inserted into the spindle is stored in a predetermined storage area of the storage device. On the other hand, the spindle head is equipped with a tool changing arm that is driven by an arm drive device, and once a stop command is given from the computer that controls the operation of this ATC device, the tool changing arm grips the tool and moves straight. After that, it rotates 90 degrees and stops. And the NC device connected to the computer is
A tool change command is given to the arm drive device based on the NC data. In addition to issuing the above instructions, the computer also
It functions as tool discrimination, tool combination discrimination, search, cycle control, etc. It discriminates the combination of large and small diameters of the tools inserted in the spindle, and when the tools cannot be replaced in the standard cycle, the magazine is The tool holding device, which can be rotated and returned, is indexed and returned, allowing used tools to be returned at random.

In addition, in a general NC processing machine equipped with a conventional ATC device, the arrangement of tools in the ATC magazine provided in the ATC device is recognized when creating NC processing data, and the necessary tools are specified. However, each tool stored in the ATC magazine has a lifespan due to blade wear, etc., and tools that have reached the end of their lifespan are replaced with new tools, and removed tools can be reused by re-sharpening the blade. or be discarded.

Therefore, in order to know the tool life, that is, when to replace the tool, the production system counts and detects the usage time or number of times the tool is used. It is designed to issue instructions for tool replacement.

However, when aiming for a flexible production system for high-mix, low-volume production, the number of tools required increases.
Significantly increase the number of ATC magazines, or
It becomes necessary to frequently replace the tools in the C magazine, and there are cases where the NC processing machine has to be stopped for tool replacement.

Problems to be Solved by the Invention However, in the conventional flexible production system for high-mix, low-volume production, tools have a limited lifespan, so the time during which the tools in the ATC magazine can be operated continuously without being replaced is currently short, and only for a certain period of time. Because it is necessary to change the tool every time, for example, continuous unattended operation of multiple workpieces is impossible.

Furthermore, if the number of ATC magazines is determined based on the greatest common divisor based on the type of work to be machined and the number of necessary tools, the number will be enormous. Furthermore, if the types of processing that can be performed by the NC processing machine are limited, the flexibility of the production system will be limited, and this will cause the problem of complicated process design.

In addition, in ATC equipment, the machining capacity is greatly affected by whether or not the tools in the ATC magazine are properly laid out according to the machining content, but with conventional ATC equipment, efficient tool exchange is possible. It was difficult to determine in advance the layout of the tools in the magazine.

Furthermore, when there are many tools required for machining, a magazine is required to store all the tools, resulting in an increase in the size of the device.

This invention has been made in view of the above circumstances, and aims to provide a tool management method that allows efficient tool exchange without increasing the size of the magazine and enables continuous unmanned operation over a long period of time. .

Means for Solving the Problems As a means for solving the above problems, the method of the present invention is a tool management method for a processing machine equipped with an automatic tool changer equipped with a magazine for storing tools. A tool change level is set for each tool, and an area is set in the magazine that stores these tools based on the height of the tool change level, and when there is no specified tool in the corresponding area in this magazine, is characterized in that tools stored in areas of the magazine with a low replacement level are replaced with the designated tools in order.

According to the method described above, each tool has a tool change level set for each tool based on its repeatability, and a predetermined area in the magazine is set based on the level of this tool change level. Store each in the area of . Then, when machining is performed using a tool, the designated tool is machined using a tool in a predetermined area within the magazine that is divided based on the tool exchange level. and,
If there is no specified tool in the corresponding area in the magazine, the specified tool is replaced with the specified tool in order from the area with the lowest replacement level in this magazine, and the specified machining is performed. conduct. As a result, the tools in the magazine are automatically selected and rearranged into an optimal tool layout according to the type of workpiece to be machined and the difference in machining content.

EXAMPLE Hereinafter, a first example will be described in which the tool management method of the present invention is applied to tool alignment work performed before the start of machining in a production system for molds, etc., equipped with a plurality of centrally controlled NC processing machines. This will be explained based on the figure and FIG.

The NC processing machine group 2 is connected to the NC processing data supply device 1, which is a control computer that centrally controls the mold production system, by a cable 3, and each NC processing machine 2a making up this NC processing machine group 2 is equipped with a magazine. Each is equipped with an ATC device 4, and the tools used for mold machining etc. by the NC processing machine 2a are inserted into the magazine of the ATC device 4 with a magazine, and are supplied with N from the NC processing data supply device 1.
According to the instructions of the C machining data, tools are automatically exchanged between the spindle or tool post of the NC processing machine 2a and the magazine of the ATC device 4 with magazine. Further, the NC machining data supply device 1 is provided with, for example, a tool stocker 5 in the same line as the NC machining machine 2a, and an ATC with a magazine of the tool stocker 5 and each NC machining machine 2a.
A tool transfer robot 6 may be run between the device 4 and the tool transfer robot 6, which is operated by a command from the NC processing editor supply device 1 and is connected to the ATC with magazine.
Insufficient tools are supplied to the magazine of the device 4 from the tool stocker 5, and unnecessary or superfluous tools are picked up and delivered to the tool stocker 5.

The NC machining data supply device 1 is inputted with NC machining data such as the type of tools required for machining in advance, as well as "tool individual information" shown in Table 1 and rA shown in Table 2.
TC magazine information" is stored.

(This page has blank spaces below.) "Individual tool information" shown in Table 1 and Table 2 is "Tool name" indicating the type of all tools required for processing in this mold production system. , "initial life" indicating the number of hours that can be used for processing, and "degree of repeatability" are stored in a file in a predefined format. Here, "reusability level" ranges from level t, which requires replacement and re-polishing after one use, to level N, which does not require replacement at all, and depends on the average machining time per time. If the value (quotient) divided by the initial lifespan is small, the level is lowered, and if it is large, the level is raised.
~N-1 levels are determined. The number of levels is at least three, and this number is increased if the degree of management is to be increased.

On the other hand, the rATC magazine information shown in Table 2 is
Each processing machine 2a has the following three pieces of information based on the magazine Na. The first is information about the magazine type. , from now on, it is a magazine dedicated to that tool.

However, when the tool reaches the end of its life, it will be replaced, but instructions will be given to replace it with a tool of the same type. Furthermore, a "random magazine" (B) is a magazine that can be used freely based on certain rules at any given time. Furthermore, the "prohibited magazine" (C) is a magazine to which the NC machining data supply device 1 does not issue instructions such as exchanging tools within the magazine.

Further, the "magazine type" is determined in advance, and the "tool name" and "remaining life" indicate the tools assigned to each magazine and the remaining life of each tool. Also"
The ``tool name'' and ``remaining life'' of the ``fixed magazine'' must be determined in advance, but if you set the ``random magazine'' as an ``empty magazine'' at the beginning, tools will be loaded according to certain rules. , "tool name" and "remaining life" are each automatically determined. In addition, the "remaining life" is the "initial life" when the tool is initially assigned, and as machining is carried out, the "remaining life" is reduced according to the usage time, and eventually when the tool life exceeds. "Remaining life" becomes a negative value.

Next, a description will be given of control in the main case where the magazine depth is determined.

<Case 1> In the case of "Random Magazine" First, once a machining schedule for a certain period of time is determined, the NC machining editor and the type of tool to be used are determined accordingly. Here, the fixed period means Work 1
Although it may be in the side wheel position or in units of multiple tools, there are multiple tools to be used within this period, and these are managed as one set. Then, the magazine position for each tool to be used is determined according to the following rules, and the tools are assigned to the random magazines.

The rules for this assignment are: First, if the tool to be used already exists in the ATC magazine, that tool will be used, and if the tool to be used does not exist in the ATC magazine, it will be transferred to an empty magazine. Assign a new tool. When a tool is newly allocated, a tool preparation instruction is issued. When the magazine Nα is determined in this manner, the command value of the tool exchange command in the NC machining data is rewritten accordingly. According to this rule, all magazines Nα of the specified tool are determined. Furthermore, when machining is actually performed, a new remaining life is determined by subtracting the usage time from the remaining life for each tool when its use is finished. When the remaining life becomes a negative value, the magazine is recognized as an empty magazine.

Next, we will explain the method for determining the "magazine depth" that is performed during tool alignment work before starting machining with the NC processing machine 2a.
This will be explained based on the flowchart shown in the figure.

When the control program starts, in step 1, the tool specified based on the NC machining data is
It is determined whether the specified tool exists in the magazine, and if the specified tool exists, the process proceeds to step 2, and an instruction is given to use the specified tool in the ATC magazine as is.

At this time, no tool preparation instruction is issued.

Then, when the process proceeds to step 3, the tool change command in the NC machining data is rewritten, and then, in step 4, the presence or absence of other specified tools is checked, and if there are still other specified tools, the process returns to step 1. , this specified tool is ATC
A determination is made as to whether it is present in the magazine.

Furthermore, if the specified tool does not exist in the ATC magazine in step 1, the process proceeds to step 5 to detect an empty magazine, and if an empty magazine is detected, a new magazine is allocated in step 6. , a tool preparation instruction is issued to the tool stocker 5 and the tool delivery robot 6, and in step 7, the specified tool is allocated in the magazine, and the tool name, allocation, position,
After the initial life etc. are determined, the process proceeds to step 3, where the tool change command in the NC machining data is rewritten, and then, in step 4, the presence or absence of other designated tools is checked again. If there is, the process returns to step 1 and it is determined whether or not this designated tool exists in the ATC magazine.

In addition, if an empty magazine is not detected in step 5, the process proceeds to step 8, and after confirming that the tool has the lowest level n (n = 1) based on the degree of repeatability, step 9 selects the tool with level n. If there is a level n tool, a command to change the tool is sent to the tool delivery robot 6 in step 10.
The tool with the lowest level n of repeatability is 1
One empty magazine is created by removing only books from the magazine, and this empty magazine has a tool stocker 5.
The specified tool carried from the tool delivery robot 6 is delivered and set, and the removed level n tool is transferred to the tool stocker 5 by the tool delivery robot 6.

In addition, in step 9, if there is no tool with the lowest level n (n=1) of repeatability, proceed to step 11, and set "n+1" to rnJ of level n.
After substituting , proceed to step 8, then determine the lowest level n (n=2) of recursive usability, and step 9
The presence or absence of a tool of level n (n=2) is checked at step IO, and if the tool exists, one tool of level n is removed from the magazine in step IO to form one empty magazine. Note that if there is no tool at level n (n=2) in step 9, step 1 is repeated until the corresponding tool is detected and one empty magazine is formed.
1, steps 8 and 9 are repeated.

Then, in step 6, a new magazine is allocated and a tool preparation instruction is sent to the tool stocker 5.
and when the tool is delivered to the tool delivery robot 6, step 7
In the tool receiver, the specified tools carried from the tool stocker 5 by the transfer robot 6 are allocated in the magazine, and the tool name, allocation position, initial life, etc. are determined. Next, the process advances to step 3, where the tool change command in the NC machining data is rewritten, and in step 4, the presence or absence of other designated tools is checked. and repeat step 4.

Then, as a result of checking in step 4, if there are no other designated tools, it is determined that all the designated tools to be used for the machining to be performed from now on are available in the ATC magazine, and the process proceeds to step 12, where the NC machining data supply device l Based on the specification of the supplied NC processing data, the tool is attached to the spindle of the NC processing machine 2a by an ATC device with a magazine, and the tool is exchanged.
Processing is performed by

When the machining is completed, in step 13 the machining time is subtracted from the remaining life of the tool used for machining to determine a new remaining life, and then in step 14 the new remaining life of the tool used is checked, If remaining life>0, the control ends.

Also, the remaining life of the tool used in step 14 is
If remaining life ≦0, the process proceeds to step 15, where the magazine in which the tool with remaining life ≦0 is placed is recognized as an "empty magazine" and the control ends.

As mentioned above, when determining the magazine Nα in which to store tools, tools are allocated to magazines while taking into account the degree of use and lifespan of the tool, so tools in the magazine are automatically allocated. The tool arrangement is rearranged to the best condition according to the machining contents. Furthermore, even if the workpiece to be machined changes and the tools used change accordingly, there is no need to change the tool arrangement in advance, and the tool arrangement is automatically changed to provide the best condition.

Case 2> In the case of a "fixed magazine" If a tool to be used is assigned to the "fixed magazine" in advance, that assigned tool is used. Also, when there is no tool to be used in the magazine, "Magazine N (
The tools to be used are assigned to the "random magazine" according to the rules of the LJ determination method (flowchart shown in FIG. 1).

Further, when the remaining life of a tool assigned to a fixed magazine becomes negative, an instruction is given to replace the tool.

In addition, "fixed magazine" allows multiple identical tools to be allocated in the same fixed magazine, and the value indicating the remaining life of the tool in use becomes negative. If so, leave the tool as it is and use the next tool. As a result, in the conventional method, each time machining is completed, the tool that needs to be removed becomes clear and must be replaced with a reground tool, but in this example, the tool that is no longer needed is If you ignore this and set the tools according to the new tool assignment, worn and unnecessary tools will be automatically removed.

As described above, according to the method of this embodiment, the tools in the ATC magazine are automatically weeded out to achieve the best arrangement according to the machining content, and the initial arrangement of the tools in the ATC magazine is It is only necessary to allocate tools to the "magazine type" and "fixed magazine", and by changing the "magazine type" according to the usage situation, the NC processing machine can be used freely. Therefore, in the case of machining that uses fewer types of tools, each tool has a long lifespan, and does not require much precision, the area of the "fixed magazine" may be enlarged. Conversely, in the case of machining that uses many types of tools and requires precision, it is more effective to increase the area of the "random magazine".

In this way, the tool arrangement within the magazine can be set in the best condition according to the work content of the processing machine, and any machining can be handled in the best condition.

Effects of the Invention As described above, according to the tool management method of the present invention, a tool exchange level is set for each tool based on the degree of repeatability, and the inside of the magazine that stores these tools is adjusted to the tool exchange level. If there is no specified tool in the corresponding area in this magazine, the area is set based on the height of Since tools are exchanged, tool exchange is performed efficiently, the tools in the magazine are automatically weeded out, and the tool arrangement is changed to the optimal one for the work content, making effective use of the magazine and making the equipment more compact. At the same time, it has the effect of enabling continuous unmanned operation for a long period of time.

[Brief explanation of drawings]

Fig. 2 shows an embodiment of the present invention, Fig. 1 is a flowchart showing a magazine Na determination method, and Fig. 2 is a block diagram showing a production system to which the tool management method of the invention is applied. It is. 1... NC processing data supply device, 2... NC processing machine group, 2a... NC processing machine, 3... Cable,
4... ATC device with magazine, 5... Tool stocker 6... Tool delivery robot.

Claims (1)

[Claims] In a tool management method for a processing machine equipped with an automatic tool changer equipped with a tool storage magazine, a tool change level is set for each tool based on the degree of repeatability, and
The area in the magazine that stores these tools is set based on the height of the tool exchange level, and if there is no specified tool in the corresponding area in this magazine, the area in this magazine with a low exchange level is set. A tool management method characterized in that the tools stored in the storage space are replaced with the designated tools in order.