JPH11226847A - Operation method of metal machining device provided with cutting tool automatic replacing means - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve production efficiency of machine work, by eliminating apprehension markedly going wrong of a program of work completion by generation of any abnormality, in a device even left as set to as to act by unmanned operation. SOLUTION: In a metal machining device provided with a cutting tool automatic replacing means 11 selecting a cutting tool D1 to D12 from a tool magazine 15 so as to automatically remounted in a spindle 10, an abnormality detection means 20 detecting abnormality of machine work by the cutting tool is provided, also the machine work relating to a workpiece 2 is divided into a plurality of machining objects, when each machining object is machined, when abnormality is detected in the abnormality detection means 20, the machining object thereof is skipped, the next machining object is machined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating a metal working apparatus provided with automatic cutting tool changing means, such as a machining center or an NC milling machine, for an unattended long time.

[0002]

2. Description of the Related Art Generally, in a metal working apparatus such as a machining center or an NC milling machine, an intended machining such as drilling, tapping, roughing, and finishing is specified in a work according to a program pre-loaded in a control device. For example, such a program is loaded on the day before a holiday, so that the intended work can be completed at the end of the holiday because it can be performed in order and unmanned driving is possible.

[0003] However, conventionally, when an unexpected accident such as breakage of a tool occurs during the work, the work is interrupted in that state, and in some cases, the work is hardly progressed. And the work was scheduled to be completed in a crazy way.

[0004] Conventionally, a series of machining operations proceed without finishing inspection of the processing accuracy of the work during the processing, leading to finish processing. Therefore, the completed work is removed from the processing device and moved to an accuracy measuring device to measure the accuracy. Then, there was a case where there was an abnormality that required accuracy was not obtained.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and aims to improve the productivity of machining by allowing a series of machining to be performed automatically and unattended as far as possible. .

[0006]

SUMMARY OF THE INVENTION To this end, a method of operating a metal working apparatus according to the present invention is directed to a metal working apparatus provided with automatic cutting tool changing means in which a cutting tool is selected from a tool magazine and automatically changed to a main spindle. In the above, an abnormality detecting means for detecting an abnormality of the machining by the cutting tool is provided, and the machining of the workpiece is divided into a plurality of machining objects, and the abnormality is detected by the abnormality detecting means while each machining object is being machined. When the processing is performed, the processing object is omitted and the next processing object is processed.
Further, the present invention provides an operation method of the metal working apparatus, wherein when an abnormality is detected by the abnormality detecting means, the alternative cutting tool is replaced on the main shaft, the processing object is processed again, and then the next processing object is processed. It is characterized by having done. Further, the present invention is characterized in that in the operation method of the metal working apparatus, the abnormality detecting means optically detects the outer shape of the blade attached to the main shaft before and after the processing.
Further, the present invention is characterized in that, in the operation method of the metal working apparatus, the abnormality detecting means detects an abnormal change in the load on the spindle. Further, the present invention is characterized in that, in the operation method of the metal working apparatus, the abnormality detecting means detects abnormal fluctuation of vibration or noise.

[0007]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a schematic perspective view showing the outline of the metal working apparatus. In the drawing, reference numeral 1 denotes a working table, and 2 denotes a work fixed on the working table by a stopper. The work is inserted into a molding surface 2a formed of a three-dimensional curved surface in order to process the work into an injection mold. The device is used to cut the through hole 2b, slide core setting portion 2c, through hole 2d, and screw hole 2e.

The working table 1 is moved in the X-axis direction in a horizontal plane along the rail 4 by the operation of the motor 3. 5 is a gate-shaped frame laid over the processing table 1;
A carriage is provided so as to be movable along a rail 8 provided on the frame by operation of a motor 7 in a Y-axis direction orthogonal to the X-axis in a horizontal plane. A spindle drive motor is provided in the carriage 6 so as to be movable in the Z-axis direction (vertical direction) by the operation of a motor 9, and a cutting tool D 1 is detachably attached to a spindle 10 rotated by the motor via a holder 14. It is attached.

A description will be given of the blade tool automatic changing means 11. Reference numeral 15 denotes a tool magazine provided on one side of the processing table 1. The tool magazine includes roughing, finishing, and drilling held by a holder 14. , A number of cutting tools D2 to D12 for thread cutting and the like. Then, the carriage 6 is moved onto the tool magazine 15,
The cutting tool to be mounted is positioned just below the main shaft 10 and the main shaft 10 is lowered, so that the cutting tool can be freely replaced on the main shaft.

Reference numeral 20 denotes an abnormality detecting means provided on the other side of the processing table 1. The abnormality detecting means 20 comprises a projector 21 for transmitting a laser beam and a light receiver 22 for moving the carriage 6. Thus, the blade D1 attached to the main shaft 10 is positioned between the light projector 21 and the light receiver 22. Then, the outer shape of the cutting tool D1 is optically detected, and the wear state thereof can be measured.

FIG. 2 exemplifies cutting tools for rough cutting and finish cutting among these cutting tools D1 to D12. A sharp cutting edge 19 is formed at the tip of a body 18 in a spiral shape.
By rotating the cutting tool by the spindle drive motor as shown by the arrow, the cutting edge forms a hemispherical locus as shown in FIG. Accordingly, the cutting tool is pressed against the work 2 fixed on the processing table 1 and the cutting tool is moved relative to the work in a three-dimensional direction (X-axis direction, Y-axis direction, Z-axis direction) in accordance with a command from the controller. By moving the workpiece in the axial direction), the workpiece can be cut into a desired three-dimensional curved surface, and the forming surface 2a can be cut and formed. In addition, blade tools D1 to D1
The cutting tool for drilling is a so-called drill made of carbide steel. Further, among the blade tools D1 to D12, the blade tools for thread cutting are so-called taps.

The outer shape of the blade attached to the main shaft 10 is moved between the light emitter 21 and the light receiver 22 before use for cutting the work 2, and the position where the laser beam is blocked while the blade is rotated at a low speed is read. Is detected by Specifically, the cutting tool attached to the main shaft 10 is first moved in the horizontal direction so that the laser beam is blocked by the body portion 18, and the center line of the cutting tool is determined from the movement position at the time of light blocking. Thereafter, the blade is moved up and down so that the laser beam hits the center line, and the tip of the blade is detected from the height at which the laser beam is shielded. By detecting the center line and the cutting edge in this way, the center point of the hemisphere drawn by the cutting edge can be obtained. Therefore, the outer shape of the cutting tool can be finely detected by moving the cutting tool from the center point in the Y-axis direction and the Z-axis direction, and detecting a position where the hemisphere drawn by the cutting edge is interrupted by a laser beam. In order to detect the wear of the cutting tool, the detection accuracy is set to 0.01 to 0.005.
It is preferable to use a high-precision one on the order of millimeters.

After measuring the outer shape of the cutting tool in this manner, the work 2 is drilled, threaded, cut, or the like using the cutting tool. After the cutting, the outer shape of the cutting tool is measured again by the same method. By comparing the data with the data after cutting, a change in the wear or breakage of the cutting tool caused by this cutting is detected, and it is determined whether the degree of wear or breakage is within a predetermined allowable range. I do. That is, if the change in the situation is larger than the allowable range, it means that sufficient precision is not guaranteed for the cutting using the cutting tool. Can be tested.

As the abnormality detecting means in the present invention, in addition to comparing the outer shape of the cutting tool before and after machining with the above-mentioned optical means, the current of the spindle drive motor is monitored during machining to reduce the load. It may be a device that detects an abnormal change that is excessively large or small, or a device that detects vibration or noise during processing by a microphone and detects the abnormal change.

In this embodiment, the object to be processed on the workpiece 2 is divided into a plurality of processing ranges A, B, and C as shown in FIG. If an abnormality is detected by the detecting means 20, if there is an alternative cutting tool, replace the alternative cutting tool with the main spindle and process the processing range again. Otherwise, remove the processing range and process the next processing range. To do it.

Next, the procedure for cutting the work area A, B, and C in this order with this apparatus will be described with reference to the flowchart of FIG. First, the processing in the processing range A is started. In this case, a predetermined rough cutting tool D1 is attached to the main spindle in step a, the outer shape of the cutting tool is measured in step b, and the processing range A is roughly cut in step c.
Then, in step d, the outer shape of the cutting tool is measured again, and in step e, whether the cutting tool is broken or abnormally worn is determined by comparing before and after processing the cutting tool. If there is no abnormality, proceed to step f,
Replace the main spindle with the blade D2 for finishing and step g
After measuring the outer shape of the cutting tool in step h, the machining range A is finish-cut in step h. Then, in step i, the outer shape of the cutting tool is measured, and in step j, the cutting tool is compared with before and after processing to determine whether the cutting tool has no breakage or abnormal wear. Moves to the flow of the processing range B shown in FIG. Table 1 shows the processing object and the tool number,
The relationship between the machining process and the machining program is shown.

[0017]

[Table 1]

If it is determined in step e that there is an abnormality, the flow advances to step k to check whether or not the tool magazine 15 has an alternative cutting tool.
The flow of the next processing range B is performed while the processing of the above is kept as it is. When there is an alternative cutting tool, it is further determined in step 1 whether or not the rough cutting in the machining range A is the first time. If it is the first time, the process returns to step a to replace the cutting tool and perform the rough cutting in the machining range A again. If it is not the first time, the flow moves to the next processing range B.

If it is determined in step J that there is an abnormality, the flow advances to step m to check whether or not the tool magazine 15 has an alternative cutting tool.
The flow of the next processing range B is performed while the processing of the above is kept as it is. If there is an alternative cutting tool, it is further determined in step n whether or not the finish cutting in the processing range A is the first time, and if it is the first time, the process returns to step f to perform the finish cutting in the processing range A by exchanging the cutting tool. If this is not the first finish of the machining range A, the flow moves to the next machining range B.

The flowchart of FIG. 5 showing the processing of the processing range B is similar to FIG. 4 in that the processing range B is roughly cut in steps a to e and the processing range B is finished in steps f to j. I do. If there is an abnormality in any of the processes, if there is an alternative cutting tool, re-grinding is performed only once. Otherwise, the machining in the machining range B is skipped and the machining in the machining range C shown in FIG. Move to flow. Then, in the machining range C, the machining range C is roughly cut in steps a to e, and
A series of machining is completed by finishing-machining the machining range C in Steps (j) to (j), and the molding surface 2a can be formed on the work 2. If there is an abnormality in any of the processes, re-sharpening is performed only once when there is an alternative cutting tool.

As described above, in the flowcharts shown in FIGS. 4 to 6, the processing target of the work 2 is divided into a plurality of processing ranges A, B,
Although the example in which the processing is performed by dividing the work into C has been described, the processing target of the work 2 may be divided into a plurality according to the processing content. That is, when the workpiece 2 serving as the injection mold is to be processed, the processing target is the nested hole 2b, the slide core setting section 2c,
As shown in Table 2, various types of processing such as nesting hole processing E for forming the through holes 2d, screw holes 2e, etc., slide core processing F, and drilling thread cutting processing G can be performed. The processing target may be classified for each processing content. That is, for example, when any abnormality is detected by the abnormality detecting means 20 during the processing of the nesting hole 2b,
The nested hole 2b is machined again by replacing the alternative cutting tool with the main spindle. Otherwise, the machining of the nested hole 2b is omitted and the slide core setting section 2c to be machined next is machined.
Similarly, if any abnormality is recognized during the processing of the slide core setting section 2c, the processing target is removed and the next processing target, such as the through hole 2d and the screw hole 2e, is drilled and threaded. Finish a series of machining.

[0022]

[Table 2]

[0023]

As described above, the method for operating the metal working apparatus according to the present invention is characterized in that the machining of the work is divided into a plurality of processing objects, and when an abnormality is detected while processing each processing object. Is designed to process the next processing object without the processing object. Therefore, even if any abnormality such as tool breakage occurs, the next processing object is continued without interruption of the work in that state. Therefore, if a series of machining operations are set to be performed automatically, even if an abnormality occurs in one processing object, the subsequent processing objects will continue without any trouble, and the work schedule will be greatly deviated. This has the beneficial effect of improving the reliability and productivity of unattended machining.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a metal cutting apparatus according to the present invention.

FIG. 2 is a side view of a distal end portion of the cutting tool.

FIG. 3 is an explanatory diagram at the time of detecting the outer shape of a tip portion of a cutting tool.

FIG. 4 is a flowchart showing an operation method of the metal working apparatus according to the present invention.

FIG. 5 is a flowchart showing a method of operating the metal working apparatus according to the present invention.

FIG. 6 is a flowchart showing an operation method of the metal working apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Processing table 2 Work 10 Spindle 11 Automatic tool replacement tool 15 Tool magazine 20 Abnormality detection means 21 Projector 22 Receiver D1 to D12

Claims (5)

[Claims] In a metal working apparatus provided with automatic cutting tool changing means in which a cutting tool is selected from a tool magazine and automatically changed to a spindle, an abnormality detecting means for detecting an abnormality in machining by the cutting tool is provided. When machining a workpiece is divided into a plurality of processing objects, and when an abnormality is detected by the abnormality detecting means while processing each processing object, the processing object is skipped and the next processing object is processed. A method of operating a metal working apparatus provided with automatic cutting tool changing means, characterized in that: 2. The method according to claim 1, wherein when an abnormality is detected by the abnormality detecting means, an alternative cutting tool is attached to the main shaft, the object to be processed is processed again, and then the next object to be processed is processed. An operation method of a metal working apparatus provided with the automatic cutting tool changing device according to claim 1. 3. An operation of a metal working apparatus provided with automatic cutting tool changing means for optically detecting the outer shape of a cutting tool attached to a main spindle before and after machining. Method. 4. A method for operating a metal working apparatus, comprising: a tool automatically changing means for detecting an abnormal fluctuation of a load on a spindle, wherein the abnormality detecting means according to claim 1 detects abnormal fluctuation of a load on a spindle. 5. A method for operating a metal working apparatus, comprising: a tool automatically changing means for detecting an abnormal change in vibration or noise.