JPS60238256A - Method of automatically returning broken tool to original point - Google Patents

Abstract

PURPOSE:To make it possible to enhance the productivity of a numerically controlled machine, by incorporating, in a numerically controlled machine, an original point return program for selecting a return path to an original point corresponding to the instant work machining step upon breakage of a tool, and for instructing the broken tool as to the return path. CONSTITUTION:A center controller C is incorporated therein with an original point returning program, as a part of a work machining program for a plurality of machining centers M1..., for selecting one of different return paths, to an original point such as, for example, an automatic tool exchanger ATC, in accordance with the instant work machining step upon breakage of a tool, and instructing the tool as to the selected path. Further, when a tool breakage detecting device 2 detects the breakage of the tool, an automatic return path to an original point such as, for example, the automatic tool exchanger ATC, corresponding to the instant work machining step, and therefore, the broken tool is exchanged with an auxiliary tool at the original point. In this condition the machining step is restarted. Further, the broken tool is returned to a centralized tool room 1 by means of an automatic transfer device ATL.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for automatically returning a damaged tool to its origin, and more specifically, it relates to a method for automatically returning a damaged tool to its origin, and more specifically, to changing the return path of the tool depending on the machining stage. This invention relates to a method for automatically returning a broken tool to the apex, for example, a tool changer, in the machining process of a workpiece.

When machining a workpiece with a numerically controlled machine tool such as a machining center, the tool may be damaged. In such a case, after stopping the machining system including the numerically controlled machine tool, the broken tool can be removed by using a return program that unconditionally returns the broken tool to its origin, for example, to a tool changer, or by manual operation. This caused the return-to-origin operation to occur.

3 ■Left-hand solution next-Le Mengzulf-Moxibustion Noriyoshi The conventional method for returning a broken tool to its origin is that even when using an automatic return program that is programmed into the computer in advance as described above, the return path of the broken tool cannot be determined. Only simple tools can be given return-to-origin action to a broken tool, and if the return path of the broken tool is complicated, the return-to-origin action is given to the broken tool in an inefficient manner by manual operation.

Therefore, if a tool such as a cutter, side cutter, or back bowler, which requires changing the return path of the broken tool to its origin depending on the machining stage of the workpiece, is damaged, the broken tool should be moved to the point where the breakage accident occurred. It is virtually impossible to automatically return the machine to the origin from the original point, and this has led to problems such as a decrease in the productivity of the workpiece processing line and a decrease in the efficiency of unmanned operation.

The main purpose of the present invention is to solve the above-mentioned problems observed in the home-return system for broken tools in known numerically controlled machine tools, and to provide a method for handling broken tools at the machining stage of the workpiece. An object of the present invention is to provide an automatic origin return method capable of preparing a plurality of types of return routes.

Another main object of the present invention is to provide a method for automatically returning a damaged tool to its origin, which is suitable for unmanned operation of a workpiece machining system.

B6 Structure of the Invention The present invention is applicable to the machining process of a workpiece (W) in which the return path to the origin when the tool (Tn) breaks is changed depending on the machining stage. At the time, a numerically controlled machine tool (M
The computer (C) connected to the tool (Tn)
) is an automatic origin return method for a damaged tool that incorporates a origin return program (PR) that instructs the damaged tool to select a return route (Rn) to the origin (ATC) corresponding to the machining stage of the workpiece (W>). This is a summary.

implementation side.

1 and 2 are flowcharts illustrating embodiments of the present invention, and FIG. 3 is an overall view of a work machining system to which the method of the present invention is applied. As shown in Fig. 3, the work machining system consists of a plurality of numerically controlled machine tools, for example, a plurality of machining centers (Mt), (M
2)-1 A centralized tool room (1) that stores a large number of tools used in these numerically controlled machine tools, and a computer that inputs the computer program (■) of the workpiece (W), such as a central controller. (C), each numerically controlled machine tool (Ml), (M2
) - a tool breakage detection device (2) is connected to the central controller (C) so as to form a control circuit for the cutting program (P).

On the other hand, in front of the centralized tool room (1) and the machining centers (Ml), (M2), etc., each of which constitutes one group, a plurality of tools ( '1''!1) are stored in groups, and a tool cassette (not shown) is transferred from the central tool room (1) to the automatic tool changer (A''l) attached to the numerically controlled machine tool (Mn). An automatic transport device (A T L ) is provided to transport the material toward 'C). The cough automatic transport device carries a workpiece (W) placed on a standby station (not shown) and a numerically controlled workpiece (Mn).
) A pallet (not shown) that can be used for the above-mentioned purpose is loaded on the conveyance truck so that it can also perform the conveyance function for the workpiece (W) that has been processed in the above-mentioned process.

In such a workpiece machining system, the first central controller (C) has a part of the machining program (P) for the workpiece (W), and when the tool (Tn) is damaged, the workpiece (Tn) is attached to the broken tool.
A return-to-origin program (PR) is incorporated that selects and instructs different return routes (Rn) to the origin, for example, an automatic tool changer (ATC), depending on the machining stage of step W).

In the embodiment illustrated in FIG.
Return to origin program (PR) in Canadian program (P)
A plurality of types are inputted corresponding to the functions of the tool (Tn) at the same time as or immediately after the start of machining by the cutting program (P).

For example, when the tap is damaged, the tap rotates in the opposite direction to the cutting direction and is extracted from the workpiece (W), and backpoling corrects the direction of the cutting edge and shifts the relative position between the blade and the cutting part and extracts it from the workpiece (W). Also, the side cutter can be used for workpieces (
The workpiece (W) is extracted from the workpiece (W) by repeating movement in the X-axis direction and the Y-axis direction, or in two or more directions along the X-axis direction, depending on the processing position of the workpiece (W). Therefore, if the tool (Tn) selected by the cutting program (P) of the workpiece is a tap, it is necessary to input a tap reversal signal to the home return program (PR), and the selected tool ( If T n ) is a side cutter, then
It is necessary to input a reverse escape displacement signal that causes the slow cutter to generate escape displacement in a plurality of directions depending on the processing stage of the workpiece (W). In the embodiment shown in FIG. 1, the home return program (Pp) is
At the start and opening of machining of the workpiece (W>) by the machine CP), or immediately thereafter, it is transferred to the central controller (0) as part of the machine nib U crumb (P), and correspondingly the machine program is In addition, an auxiliary signal for selecting the above-mentioned return-to-origin program (PR) to be activated when the tool ('I''n> is broken), such as a signal for starting an external automatic tool changer from a numerically controlled machine tool or a signal for starting an external automatic tool changer from the numerically controlled machine tool. Incorporates control functions such as index rotation angle control signals that regulate the amount of table movement.

In this way, the damaged tool is provided with an automatic return path (Rn) to the origin corresponding to the machining stage of the workpiece (W), for example, an automatic tool changer (ATC), and the damaged tool is provided with a spare tool (Rn) at the origin. Tn) and processing is restarted in this state.

FIG. 2 shows different embodiments of the invention, in which the workpiece (W
), the tool information of the used tool (Tn), such as tool number, tool length and/or diameter,
The type of tool, etc. is registered in the central controller (C). After starting machining of the workpiece (W) using the Canadian program (P),
The movement trajectory of the tool (Tn> is monitored and the position of the tool is recorded for each displacement point of the cutting block.The workpiece (
If the tool (Tn) is damaged during machining W), the position of the tool (i' n ) at the time of breakage is determined by the central controller (C).
The escape direction to be transmitted to the damaged tool is calculated by comparing it with the numerical control data input into the machine. A return-to-home program (PR) for the damaged tool is automatically created based on the escape direction calculated in this way, and the return-to-home program (Pp) is a program (P) for the workpiece (W).
will be sent to. In this way, a home return path (Rn) is prepared for the damaged tool based on the home return program (PR).
The damaged tool is located at the origin, e.g. automatic tool changer W (ATC).
At this point, the spare tool (Tn) is replaced, and machining of the workpiece (W>) is restarted in this state.

C8 Effects of the Invention As can be understood from the above explanation, according to the method of the present invention,
A tap whose return path to the origin in the event of breakage consists of a straight line, five or curved lines with two or more axes differing in direction,
A fully automatic origin return function can also be provided to tools such as bank polling or side cutters.

Therefore, the present invention can bring about significant improvements in improving the productivity of numerically controlled machine tools and promoting labor savings in machining processes.

[Brief explanation of the drawing]

1 and 2 are flowcharts illustrating embodiments of the present invention, and FIG. 3 is an overall view of a work machining system to which the method of the present invention is applied. (Tn) - Tool, (W) - Workpiece, (Mn) - Numerical control machine tool, (C,) - Computer, (ATC) -
origin, (Rn) - return path, (P) - workpiece machine program, (PR) - tool return to origin program.

Claims (1)

[Claims] (1) In a workpiece machining process where the return-to-origin path in the event of a tool breakage differs depending on the machining stage, a computer connected to a numerically controlled machine tool that processes the workpiece is notified of the broken tool when the tool breaks. An automatic origin return method for a damaged tool characterized by incorporating an origin return program that selects and instructs a return route to the origin corresponding to the machining stage of the workpiece.