JP2002169607A - Management method for machining abnormality palette in fms cell and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discharge an abnormal workpiece from a machine tool if the machining abnormality occurs in the machine tool in a FMS cell, and to manage the palette in which the machining abnormality has occurred so that the continuous subsequent work can be carried on. SOLUTION: This management method constantly monitors whether or not the machining abnormality occurs during the machining by each of NC machine tools 10a, 10b, if the machining abnormality is detected, stops the running of the NC machine tool in which the machining abnormality has occurred, for evacuating the workpiece in which the machining abnormality has occurred to a palette stocking station, a palette conveying equipment 14 carries out the palette on which the workpiece is place from the NC machine tool to the palette stocking station 12, and resumes, after the palette is discharged, the subsequent work with the machine tool.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for managing a processing abnormal pallet in an FMS cell, and more particularly to a processing apparatus for processing when a processing abnormality such as tool breakage or tool wear occurs during processing with a machine tool. The present invention relates to an apparatus for managing a processing abnormal pallet in an FMS cell that enables a pallet on which an object is placed to be automatically discharged from a machine tool.

[0002]

2. Description of the Related Art FMS (Flexible Manufacturing System)
tem) is composed of multiple NC machine tools, a pallet transfer device, a pallet storage station, and a computer that controls these facilities in an integrated manner. It is.

In this type of FMS cell, a pallet on which a work is placed is sequentially sent from a pallet storage station to a machine tool by a transfer device according to a pre-registered schedule, and the pallet is automatically transferred in accordance with the processing order of the registered work. It is processed into. Such FMS
In a cell, unattended operation can be performed at night or the like, so that high productivity can be increased.

[0004] When an automatic operation is performed in the FMS cell, it is firstly important to prevent processing abnormalities such as tool breakage and tool wear from occurring, but in practice, occurrence of processing abnormalities is inevitable. If a processing abnormality occurs in the machine tool, if the processing is continued as it is, the workpiece becomes a defective product or the machine tool breaks down.

There are various conventional systems for detecting the occurrence of such a processing abnormality. Conventionally, a machining error detection system is mounted on each machine tool, and when the machining error is detected, machining on the machine tool is stopped. After stopping the machine, the monitoring worker examines the current state of the processing abnormality, removes the cause of the processing abnormality, for example, by removing a broken tool, and determines whether to continue processing,
The operation of the machine tool has been resumed.

[0006]

However, the conventional machining abnormality detection system detects an abnormality in an individual machine tool and stops the operation of the machine tool.
At present, it is not linked to the continuation of the entire continuous operation of the FMS cell.

For this reason, in the case of manned operation, as described above, the automatic operation of the FMS cell can be restarted by human intervention. Remains stopped, and the subsequent operation of the FMS cell does not proceed until the worker returns to the stopped state, resulting in a significant decrease in the operation rate of the production equipment.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art and, when a machining error occurs in a machine tool in an FMS cell, discharge the abnormal work from the machine tool. Another object of the present invention is to provide a method and an apparatus for managing a processing abnormal pallet in an FMS cell which enable a continuous succeeding operation to proceed.

[0009]

In order to achieve the above object, the present invention provides a plurality of NC machine tools and a pallet transfer device for transferring a pallet on which a workpiece is mounted to a designated NC machine tool. A pallet storage station, and a method for managing abnormal machining pallets in an FMS cell having a production management system for integrally managing these facilities, wherein abnormal machining occurs during machining in each NC machine tool. The NC machine tool where the machining error has occurred is stopped, and if the machining error has occurred, the work machine in which the machining error has occurred is evacuated to the pallet storage station. The pallet on which the workpiece is placed is unloaded from the NC machine tool to the pallet storage station by a pallet transfer device. It is characterized in that to resume the subsequent work on the machine.

Further, the present invention comprises a plurality of NC machine tools, a pallet transfer device for transferring a pallet on which a workpiece is mounted to a designated NC machine tool, and a pallet storage station. An apparatus for managing a processing abnormality pallet in an FMS cell having a production management system that performs integrated management, comprising: a processing abnormality detecting means for detecting a processing abnormality during processing of each NC machine tool; Processing abnormality monitoring means for suspending the operation of the NC machine tool having the processing abnormality, giving a command to discharge the pallet from the NC machine tool to the NC machine tool, and generating a signal notifying the occurrence of the processing abnormality; When receiving the processing abnormality notification signal, a command to retract the pallet to the pallet storage station is given to the pallet transport device. , It is characterized in that the pallet is provided with a resume system management controller subsequent working with the machine tool after being discharged.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method and an apparatus for managing an abnormal machining pallet in an FMS cell according to the present invention will be described below with reference to the accompanying drawings. FIG.
Shows an example of an FMS cell to which the present invention is applied. In the FMS cell, a plurality of NC machine tools (five horizontal machining centers in FIG. 1) 10a to 10e constitute a machine tool group, and these NC machine tools 10a to 10e are pallet stockers as pallet storage stations. 12 are arranged in a line along a transport line 13 provided on the front side. A setup station 15 is provided at one end of the transport line 13.

The pallet stocker 12 is a three-dimensional stocker capable of storing a large number of pallets. The pallet can be put in and taken out of the stocker at a position designated by the transfer device 14.

FIG. 2 is a block diagram showing a control system of the FMS cell. The system controller 20 is a control device that organically links the machine tool group 10 including the NC machine tools 10a to 10e and the transfer device 14 to integrally manage machining, and is configured by, for example, a so-called FA computer. I have. NC machine tools 10a to 1
The group of machine tools 0e is controlled by a CNC device 22, and the system controller 20 and the CNC device 22 are connected via a communication adapter 23 by an optical modem and an optical cable C1. Also, the transport device 1
4 is connected to the system controller 20 via a communication adapter 23 via a communication cable C2 conforming to the RS-232C standard. by this,
The system controller 20 controls the C of the NC machine tool group 10
Mutual communication with the NC device 22 and the control panel 24 is possible.

Next, FIG. 3 shows each of the machine tools 10a to 10a.
FIG. 3 is a block diagram illustrating a configuration of a CNC device 22 that controls e. The CNC device 22 includes a PLC device 26 and an NC device.
The NC device 28 includes a machine tool 10a according to a machining program created in advance.
To 10e are subjected to predetermined processing.

The PLC device 26 is a programmable logic controller that controls the sequence of the NC device 28 according to a sequence program.
8 is started and stopped, and a command from the system controller 20 is received, and various information on the NC machine tool is transmitted to the system controller 20.

Each of the machine tools 10a to 10e is provided with a processing abnormality detecting device 30 for detecting a processing abnormality such as tool breakage or tool wear. This processing abnormality detection device 30
A processing abnormality is detected from a change in the current value of a motor for driving the spindle, and the like, and is connected to the PLC device 26.

When the PLC device 26 detects a machining error, it sends a signal notifying the occurrence of the machining error to the system controller 20. When receiving the report of the processing abnormality, the system controller 20 stores the pallet state management data 35 stored in a storage device (not shown) in the management data of the pallet placed on the table of the machine tool in which the processing abnormality has occurred. Information for identifying the status of the processing abnormality is written. The pallet on which the status of this machining error is written is displayed on the monitor 36
Is distinguished by color so that it can be distinguished from other normal palettes.

FIG. 4 is a plan view showing the arrangement of machine tools in the FMS cell to which the present invention is applied. In FIG. 4, two machine tools 10a and 10b are shown, and others are omitted. The pallet stocker 12 shows a state in which ten pallets P1 to P10 are stored for simplicity.

In FIG. 4, each machine tool 10a, 1
0b, the table 32 is arranged on the front side of the machine body. A carry-in station 33 and a carry-out station 34 are arranged between the table 32 and the carrying path 13, and the pallets carried by the carrying device 14 are
It is carried into the carry-in station 33 and supplied to the table 32 by a pallet changer (not shown). The pallet that has been processed is discharged by the pallet changer to the unloading station 34, where it is placed on the transfer device 14 and transferred to the machine tool where the next processing is performed.

Hereinafter, the management of the abnormal machining pallet according to the present invention will be described with reference to the flowcharts shown in FIGS. First, in FIG. 4, during processing, the pallets, which have been set up at the setting station 15, for example, pallets P1, are sequentially supplied to the machine tool 10a by the transfer device 14 in order. Machine tool 10
The pallet P1, which has been processed in a, is discharged from the machine tool 10a and then supplied to the machine tool 10b for processing in the next step. In this way, the pallets P1, P2, P3,.
Processing through

During such machining, each machine tool is constantly monitored by the machining abnormality detection device 30 shown in FIG. 3 for occurrence of machining abnormality such as tool breakage (step S1).

Therefore, for example, it is assumed that a processing abnormality has occurred in the machine tool 10b. At this time, the PLC device 26
When the occurrence of the processing abnormality is detected by receiving the abnormality detection signal from the processing abnormality detection device 30 (yes in step S2)
s), the PLC device 26 gives a command to the NC device 28 to stop machining in the machine tool 10b (step S3). As a result, after the operation of the machine tool 10b is stopped and the machining is stopped, the PLC device 26 subsequently
A command to discharge the pallet to the carry-out station 34 is given to the NC device 28 (step S4). This allows
A pallet changer (not shown) is operated, and the pallet having the processing abnormality is discharged from the machine tool 10b to the unloading station 34. Next, the PLC device 26 transmits a signal notifying that a processing abnormality has occurred to the system controller 20 (step S5). Then, the system controller 20, which has received the report of the processing abnormality, sets the pallet state management data 35 stored in the storage device (not shown).
Then, information for identifying the status of the processing error is written in the management data of the pallet, whereby the pallet is displayed in a different color from the other pallets on the screen of the monitor 36, and the processing error has occurred. Is identified (step S6). During the evacuation of the pallet, normal processing is performed on other machine tools.

On the other hand, the system controller 20, which has received the processing abnormality notification signal, transmits to the control panel 24 a command to transport the pallet to the designated position of the pallet stocker 12, whereby the transport device 14 transfers the pallet to the pallet. It is conveyed and stored in a predetermined place of the pallet stocker 12 (step S7).

In this way, after the pallet on which the workpiece having the machining abnormality has been placed is automatically stored in the pallet stocker 12, the system controller 20 starts the next scheduled operation on the machine tool 10b. , The automatic operation is restarted (step S8), and the subsequent pallet is carried into the machine tool 10b. Thereafter, the continuous machining is restarted according to the preset schedule.

In this manner, the pallet on which the workpiece having the machining abnormality has been placed is automatically ejected, and then the pallet for the subsequent machining operation is carried in. A series of processes can be continuously operated without stopping.

The pallet retracted to the pallet stocker 12 is identified by a color on the screen of the monitor 36 attached to the system controller 20 as a pallet in which other workpieces have no processing abnormality. After switching from the unmanned operation to the manned operation, the operation is carried out to the setup station 15 so that the operator can confirm the fact that the processing abnormality has occurred.

There are various types of processing abnormalities, and it is necessary for the operator to actually confirm the details of the abnormalities. That is, there is a case where the work must be discarded due to scratches, breakage, or the like due to the processing abnormality, or there is a case where the work itself has no damage due to processing abnormality due to a worn tool. The operator checks the contents of the processing abnormality, and if there is no abnormality in the workpiece itself, the operator can set up the workpiece and send it again to the subsequent processing.

[0028]

As is apparent from the above description, according to the present invention, when a processing error occurs in a machine tool in an FMS cell, the abnormal workpiece is discharged from the machine tool and continuously processed. Since the following work can be advanced, the operation rate of the equipment can be significantly improved without stopping the processing of the FMS cell even in the unmanned operation.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an FMS cell to which the present invention is applied.

FIG. 2 is a block diagram showing a control system of an FMS cell to which the present invention is applied.

FIG. 3 is a block diagram showing a control unit of the machine tool of the FMS cell.

FIG. 4 is a layout diagram of an FMS cell to which the present invention is applied.

FIG. 5 is a flowchart showing a procedure of managing a processing abnormal pallet according to the embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 machine tool 12 pallet stocker 13 transfer path 14 transfer device 15 setup station 20 system controller 22 CNC device 30 processing abnormality detection device 32 table 33 carry-in station 34 carry-out station

Claims (3)

[Claims] A plurality of NC machine tools; a pallet transfer device for transferring a pallet on which a workpiece is placed to a designated NC machine tool; and a pallet storage station, and these facilities are integratedly managed. This is a method of managing a machining error pallet in an FMS cell having a production management system that performs a continuous monitoring of whether or not a machining error has occurred during machining with each NC machine tool. The operation of the NC machine tool in which the machining abnormality has occurred is stopped, and the pallet on which the workpiece is placed is moved to the pallet storage station in order to retreat the workpiece in which the machining abnormality has occurred to the pallet storage station.
C. A method for managing a processing abnormal pallet in an FMS cell, wherein the pallet is carried out from the machine tool to the pallet storage station by a pallet transfer device, and after the pallet is discharged, the subsequent work on the machine tool is restarted. 2. A plurality of NC machine tools, a pallet transfer device for transferring a pallet on which a workpiece is mounted to a designated NC machine tool, and a pallet storage station, and these facilities are integratedly managed. A pallet management device for processing abnormalities in an FMS cell having a production management system, comprising: a processing abnormality detecting means for detecting a processing abnormality during processing of each NC machine tool; and a processing abnormality occurring when the processing abnormality is detected. While temporarily stopping the operation of the NC machine tool, and giving a command to discharge the pallet from the NC machine tool to the NC machine tool,
A processing abnormality monitoring means for generating a signal for notifying the occurrence of a processing abnormality; and, upon receiving the processing abnormality notification signal, giving a command to the pallet transfer device to retract the pallet to the pallet storage station, And a system management control means for resuming a subsequent operation on the machine tool after being ejected. 3. The system management control means includes processing abnormality identification means for writing data for identifying a processing abnormality in data for managing a state of a pallet, and for identifying a workpiece having a processing abnormality. 3. The apparatus for managing abnormal machining pallets in an FMS cell according to claim 2, wherein: